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online measurement of diameter and temperature in the melt-spinning and melt blowing process

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Online Measurement of Fiber Diameter and Temperature in the Melt-Spinning and Melt-Blowing ProcessesVishnu T.Marla,Robert L.Shambaugh,*and Dimitrios V.PapavassiliouSchool of Chemical,Biological,and Materials Engineering,The Uni V ersity of Oklahoma,100East Boyd Street,SEC T335,Norman,Oklahoma 73019Online measurements of fiber temperature and diameter were made for both the melt-spinning and the melt-blowing processes.The fiber temperature was determined by infrared thermography,and the fiber diameter was determined by high-speed photography.These measurements were then compared with predictions made with mathematical models for melt spinning and melt blowing.There was good agreement between the models and the experimental results,and the agreement was best when heat-transfer correlations developed specifically for fine fibers (cylinders)were used.IntroductionMelt spinning and melt blowing are widely used commercial processes for the manufacture of fibers and nonwovens.For these two processes,experimental measurements of fiber properties along the spinline are useful for understanding the process of fiber formation.Furthermore,these measurements can serve as valuable data for testing against the predictions of mathematical models for the processes.In melt spinning fiber motion is primarily along the spinning direction (1D motion),while in melt blowing the fiber has motion in the spinning direction as well as extensive vibrational motion (so that the fiber has 3D motion).However,the processes are similar in that both have a rapidly attenuating fiber.In the work described herein,experimental data were compared with the predictions of previously developed mathematical models for melt spinning and melt blowing.Some past studies have focused on the online measurement of fiber diameter,fiber temperature,fiber velocity,birefringence,and structural changes along the spinline.Online fiber velocity was measured using laser Doppler velocimetry.1,2Online birefringence was measured with a polarizing microscope 3-5or crossed polarizers.6Online X-ray characterization of the fiber during melt spinning was used to monitor structural changes along the threadline.7Fiber diameter is a key parameter in fiber spinning,and the online measurement of this parameter has been attempted in a number of ways.For example,Lu and Spruiell 3used a polarizing microscope that was mounted sideways such that the running fiber could be seen through the eyepiece of the microscope.By using a calibrated micrometer eyepiece,the fiber diameter could be measured.Bheda and Spruiell 8measured the fiber diameter in melt spinning using a Zimmer diameter monitor based on the principle of electrooptic back illumination.Their setup permitted several measurements at each spinline position,and a statistical analysis was conducted to determine the average diameter.A similar setup for measuring the fiber diameter profile was used by several other research groups.9,10Haberkorn et al.11used a forward laser light scattering (LLS)technique to determine the fiber diameter along the spinline.The fiber diameter was determined from the distance between the interfer-ence maxima on the diffraction pattern that was recorded on a charged couple device (CCD camera).Wallen et al.12used smallangle light scattering to study the fiber diameter and orientation in the melt-blowing process.Bansal and Shambaugh 4,5used high-speed photography for measuring the fiber diameter in both the melt-spinning and melt-blowing processes.Oh et al.13obtained the diameter profile for solid and hollow fibers in the melt-spinning process by making online measurements using a special capturing device that trapped and froze the filament.The captured filaments were cut with a microtome,and the inner and outer fiber diameters were measured with a microscope.Bresee and Qureshi 14used a pulsed laser in conjunction with a rapid frame rate camera to acquire the fiber diameter in the melt-blowing process.Zhao and Wadsworth 15used a 51cm long rigid mechanical arm to collect fiber at different locations along the melt-blowing spinline and analyzed the collected fibers using an optical microscope and image analyzing software.Recently,Golzar et al.16used an infrared camera to measure the fiber diameter in the melt-spinning process.However,due to resolu-tion limitations of the infrared camera,diameter measurements below 25µm were not possible.Moore et al.17used an ensemble laser diffraction (ELD)technique to determine the fiber diameter distribution at a location below a melt-blowing die.One method of measuring the fiber temperature profile is the use of infrared radiation.An infrared technique allows for noncontact measurement of the fiber temperature.For example,Lu and Spruiell 3used a Barnes infrared microscope to measure the temperature of the filament in the melt-spinning process.They used a null-balance technique where the temperature of the filament was compared with that of a small heater at a known temperature.The radiation from the filament was compared with that of the heater,and the filament temperature was assumed to be the same as the heater temperature at the point where the filament radiation matched the radiation from the heater.Apparently,the assumption was made that the emissivity of the heater was the same as that of the filament.Because an IR microscope has a depth of field on the order of a few micrometers,an IR microscope cannot be used to measure fiber temperatures during melt blowing (where the fiber vibrational motion is much greater than a few micrometers).For temperature measurements on fibers during melt blowing,Bresee and Ko 18used a digital IR thermometer with adjustable emissivity.They inserted the thermometer probe into the fiber stream and measured the temperature of the fibers as the fibers collected on the probe surface.However,since this technique requires insertion of a probe in the polymer stream,the technique cannot be applied to melt spinning.Bansal and Shambaugh 4,5*To whom correspondence should be addressed.Tel.:(405)325-6070.Fax:(405)325-5813.E-mail:shambaugh@.Ind.Eng.Chem.Res.2009,48,8736–8744873610.1021/ie900615n CCC:$40.75 2009American Chemical SocietyPublished on Web 08/20/2009and de Rovere and Shambaugh19used a slit response factor or SRF curve to account for the spatial resolution of their IR camera while measuring the temperature offibers in the melt-spinning and melt-blowing processes.The SRF curve corrects for the errors involved in measuring the temperature offine fibers(where,on the view frame of the camera,thefiber diameter has a size that is on the order of a pixel).In the new work described herein,the generic SRF curve provided by the manufacturer of the camera(FLIR)was replaced by a more accurate temperature correction scheme that was specifically tailored to thefine diameterfibers used in our work.Errors in IR measurement can also be attributable to incorrect estimation of object emissivity.Emissivity values are listed in the literature,and values are also provided by manufacturers of IR cameras.However,emissivity has been known to be a function of the thickness in the case of thin polymerfilms,20 the diameter in the case of cylindrical objects,21and the angle of vision.Since the work of Marla et al.21is directly applicable to the type of polymerfilaments produced during melt spinning and melt blowing,the calibration techniques suggested in their paper are an accurate way of measuringfiber temperature in these spinning systems.Both melt spinning and melt blowing involve heat transfer from a polymerfilament to an air stream thatflows across the filament.There are several correlations for heat transfer from relatively large diameter cylinders(wires)to air in parallel flow.22-24The heat-transfer correlation of Kase and Matsuo25 is commonly used in mathematical models for melt spinning and melt blowing;this correlation has a range of applicability that is appropriate for smallfiber diameters.However,use of the Kase and Matsuo correlation might be the cause of overprediction of the temperature(when compared with ex-perimental data).For melt spinning,an example of this overprediction can be found in de Rovere and Shambaugh.19 For melt blowing,see the article by Bansal and Shambaugh.5 Recently,new Nusselt number correlations were developed for heat transfer fromfine cylinders.26These correlations were produced by carefully measuring the change infiber temperature with a calibrated infrared camera.The correlations that were developed from this recent experimental study areandFor comparison,the correlation of Kase and Matsuo25isAs one of the goals of this paper,we evaluated the performance of the newly developed correlations by inserting them into mathematical models for melt spinning and melt blowing and comparing the predicted temperature profiles with online temperature measurements.Details of Experimental SetupMelt Blowing.Figure1shows the experimental setup for measurement of thefiber diameter and temperature in the melt-blowing process.The setup was very similar to that used by Marla and Shambaugh.27A Brabender extruder of19.1 mm(0.75in.)diameter and381mm length was used to melt and pressurize the polymer.The barrel had a20:1L/D ratio and a3:1compression ratio.The polymer exiting from the extruder was then fed to a modified Zenith pump that accurately metered molten polymer through a melt-blowing slot die with a single polymer capillary.The polymer capillary had a diameter of0.420mm.The two air slots were setflush with the nose piece,and the slot widths were0.65mm.Each slot had a length of74.6mm(2.94in.).The die assembly was heated with two250W cartridge heaters.A thermal mass flow meter was used to measure the airflow rate,which was maintained at either100or125slpm(at standard conditions of21°C and atmospheric pressure).The centerline air velocity and temperature below the die were determined using a pitot tube and thermocouple probe,respectively.The details of this equipment can be found in Marla et al.21Thefiber diameter profiles were obtained using high-speedflash photography;see the details in ref5.The camera used was a Nikon N90S equipped with a105mm Nikon macro lens, and the illumination was provided by a Sunpak Auto622flash.The polypropylene(PP)used in the experiments was 88MFR Fina Dypro isotactic polypropylene.This polymer had an M w of165000g/mol and M n of41500g/mol. Polybutylene(PB)resin was also spun.This polybutylene was grade0400manufactured by Basell Polyolefins;the polybutylene MFR was20.The temperature of the polymerfilaments was determined using an IR(infrared)camera.The IR camera used in the study was a ThermaCAM S60manufactured by FLIR Systems.The spectral range for this camera is7.5-13µm(longwave).The IR image displayed had a resolution of640×480pixels,while the actual number of thermal detector sensors or elements was 320×240.The other prominent features of this IR camera can be found on the manufacturer’s Web site and the camera’s user manual(FLIR ThermaCAM S60User Manual).The IR lens on this camera has afield of view(FOV)of24°×18°with a minimum focus distance of0.3m or11.81in.The camera also had a100µm close-up lens for which the minimum focus distance is80mm,while the maximum working distance is 110mm.The close-up lens had the advantage that it could measure the temperature of small targets with greater accuracy. Unless otherwise mentioned,all temperature measurements in the present study were made with the100µm close-up lens. The IR camera had the capability to record60temperature measurements per second,and a real-time plot of theseNu)1.4+0.0141Re for24e Re e150(1) Nu)0.3575Re0.46for150e Re e923(2) Nu)0.42Re0.334(3)Figure1.Experimental equipment used for spinningfibers while measuring fiber diameter and temperature.Ind.Eng.Chem.Res.,Vol.48,No.18,20098737measurements was displayed on the monitor of a PC that was connected to the IR camera by means of an IEEE1394(firewire) connection.Since the100µm close-up lens has a small depth offield and melt-blownfibers exhibit significant motion in a plane perpendicular to the majorfiber axis(the spinning direction),thefiber moved in and out of focus of the IR camera. Whenever thefiber was in focus,the temperature plot displayed a spike in thefiber temperature.This spike was then taken as the rawfiber temperature(i.e.,a temperature in need of correction forfield of view,emisssivity,etc.).Beginning at3 cm below the die,measurements were taken at intervals of1 cm until a position13cm below the die was reached.Beyond 13cm,thefiber temperature was measured at15,17,20,and 25cm below the die.Close to the die,infrared radiation from the die itself can affect the measuredfiber temperature.Thus, no measurements were made closer than3cm to the die.The variation of emissivity withfiber diameter(for both polypro-pylene and polybutylene),the procedure for using the SRF curve,and the operating procedure of the IR camera are described elsewhere.21The base conditions for the experiments, unless otherwise specified,were m p)0.75g/min,T f,die)310°C,T a,die)368°C,and airflow rate)125slpm.Melt Spinning.For melt spinning,the experimental setup was the same as that for melt blowing except that the air supply was turned off and the melt-blowing die was replaced with a single-hole spinneret.The capillary in this spinneret had a diameter of0.407mm(0.016in)and a length of2.97mm (0.1169in).Both polypropylene and polybutylenefibers were spun.The molten polymer exiting the die was drawn by a mechanical take-up roll located1.4m below the spinneret.For experiments with both polypropylene(PP)and polybutylene (PB),the spinneret temperature was kept at200°C,and the polymer throughput was kept at1g/min.For polypropylene, the mechanical take-up roll was used at six spinning speeds ranging from500to1750m/min;for polybutylene the roll speeds were500and1000m/min.Thefiber diameter and temperature were measured in the same way as in melt blowing. Beginning from3cm below the die,the temperature measure-ments were made at1cm intervals up to12cm below the die. Beyond12cm,the measurements were made at15,17.5,and 20cm below the die.Modeling DetailsMelt Spinning.The energy balance over a differential element of size∆y of thefiber at any distance y below the spinneret can be written aswhere m p)mass throughput of the polymer(kg/s),C p,f) specific heat of the polymer(J/kg·K),d y)fiber diameter at any distance y below the spinneret(m),h)convective heat-transfer coefficient(W/m2·K),T a)temperature of the ambient air(°C),and T f)fiber temperature(°C).At very high spinning speeds(in excess of4000m/min),the stress in the polypropylenefiber increases enough to induce crystallization in thefiber.4Equation4neglects the heat gained by the polymer due to crystallization,and for the moderate spinning speeds in our experiments,this is a reasonable assumption.Thefiber diameter profile needed for solving eq4 was obtained using high-speedflash photography.For the conditions of our experiments,the specific heat capacity of both polypropylene and polybutylene do not vary significantly with temperature and can be assumed to be constant.Then,eq4is an ordinary differential equation with the temperature of the fiber,T f,as the only dependent variable.This ODE can be numerically solved for T f using the fourth-order Runge-Kutta method.By using different correlations for calculating the convective heat-transfer coefficient in eq4,the predictedfiber temperature can be compared with the results from online temperature measurements.Melt Blowing.For melt blowing,the model of Marla and Shambaugh28was used to predict the three-dimensional motion of afiber as it was being formed below a melt-blowing die. This model involves the simultaneous solution of the momen-tum,energy,and continuity equations.Predicted parameters includefiber attenuation,vibration frequency,vibration ampli-tude,temperature,and stress.The model was solved using both the Kase and Matsuo heat-transfer correlation and the correlation developed by Marla et al.26Results and DiscussionMelt Spinning.High-speedflash photography was used to measure the onlinefiber diameter.Figure2shows some representa-tive plots of online diameter profiles for polypropylene spun at 500and1750m/min.Thefibers attenuate rapidly close to the spinneret,and thefibers spun at1750m/min attenuate faster than thefibers spun at500m/min.The diameter profiles werefit to fourth-order polynomials so that they could be inserted in eq4as a function of distance y from the spinneret.Table1shows the coefficients of the fourth-order polynomial for each spinning speed for both PP and PB.Figure3shows the results from the online temperature measurements for PP at six different spinning speeds.Thefiber temperatures were determined with the aforementioned IR camera along with the calibration procedure developed in ref 21.Higher spinning speeds result infiner diameters that possess less sensible heat,andfinerfibers cool at a faster rate than thickerfibers.However,in the spinning process thesefinefibers are exposed to the ambient air for less time than the thicker filaments(because,at a constant polymer throughput,thicker filaments have a slower spinning speed).These two effects tend to counterbalance each other such thatfiber temperature shows little dependence on spinning speed.In fact,previous studies4,8 showed that the take-up speed did not significantly affect them p Cp,fd Tfd y)-πhdy(Tf-Ta)(4)Figure2.Fiber diameter as a function of position below the die for themelt spinning of polypropylene.Data are shown for two different windupspeeds.8738Ind.Eng.Chem.Res.,Vol.48,No.18,2009fiber temperature profile.As Figure 3shows,in our present experiments it appears that the spinning speed affects the fiber temperature (the effect is of the order of 10-25°C).For example,at 20cm below the die,the temperature of the fiber spun at 1750m/min is 90°C,while for fiber spun at 500m/min the temperature is 115°C.For the case of PB spinning,Figure 4shows the online temperature measurements at two different spinning speeds.The trends for PB parallel the trends observed for PP.Statistical examination of the data in Figures 3and 4indicates that the standard deviation of the data points is about 10.8°C.Figure 5is a plot of fiber temperature versus position for PP spinning at a windup speed of 500m/min.The diamond symbols are the experimental values of the temperature.These temper-ature values were corrected for fiber diameter (i.e.,corrected for emissivity changes)by using the procedure described by Marla et al.21The solid and dotted lines are predicted temper-ature profiles obtained by solving eq 4.For the solid line,the correlation of Marla et al.26was used in eq 4.For the dotted line,the correlation of Kase and Matsuo 25was used.The temperature profile obtained by using the Kase and Matsuo heat-transfer correlation was high compared to the experimental data.However,the temperature profile obtained by using the cor-relation developed by Marla et pared favorably with experimental data.Figures 6,7,8,9,and 10are similar to Figure 5except that these five figures are for spinning speeds of,respectively,800,1000,1200,1500,and 1750m/min.As was the case for Figure 5,these five figures show that there is a good match between the experimental data and the model predictions made with the correlation of Marla et al.26Also,use of the Kase and Matsuo correlation gives temperature profiles that are higher than the actual temperature measurements.Figures 11and 12are temperature measurements and predictions for the spinning of PB at,respectively,500and 1000m/min.As was the case for PP spinning (Figures 5-10),there is a good match between the experimental data and model predictions made using the correlations 1and 2.As with PP spinning,the use of the Kase and Matsuo correlation gave temperature profiles that were higher than the actual temperature profile.Table 1.Coefficients of the Fourth-Order Polynomial Used to Fit the Diameter Profiles Obtained from High-Speed Flash Photography during the Melt-Spinning Processcoefficients of the polynomial ay 4+by 3+cy 2+dy +epolymer spinning speed (m/min)a b c d e polypropylene500-1.776×10-14-0.143 6.775-112.350878.160800 4.867×10-30.40711.509-145.898938.571000 2.012×10-2 1.03819.707-179.945973.0641200 1.714×10-2-0.91418.146-172.923942.9201500 1.037×10-2-0.60713.674-152.677913.79717509.644×10-3-0.55412.934-150.273892.569polybutylene5000.023-1.07318.297-160.111954.90410000.0070.3728.286-108.846872.800Figure 3.Fiber temperature as a function of position below the die for the melt spinnng of polypropylene.Data are shown for six different windupspeeds.Figure 4.Results for polybutylene melt spinning:fiber temperature as a function of position below the die.Data are shown for two different windupspeeds.Figure 5.Model predictions of fiber temperature for the melt spinning of polypropylene.Two different correlations for Nusselt number were tested in the model.Experimental data are also included for comparison.Ind.Eng.Chem.Res.,Vol.48,No.18,20098739Melt Blowing.To solve the equations that describe melt blowing,air velocity and air temperature are needed as boundary conditions.Figures 13and 14show the centerline air velocityand temperature,respectively,at positions below the melt-blowing die for the conditions shown on the figures.These velocity and temperature measurements were made in the absence of the polymer,i.e.,the polymer flow was stopped during these measurements.Several other researchers 29-32have made measurements of the air velocity and temperature below slot dies in different configurations and developed dimensionless empirical correlations for the velocity and temperature fields.Recently,computational fluid dynamics (CFD)has been used to investigate the flow fields below melt-blowing slot dies.33-35As Figure 13shows,the centerline air velocity decreases along the threadline with the velocity being slightly higher for the 125slpm case compared to the 100slpm case.As Figure 14shows,the centerline air temperature profile shows a trend similar to the air velocity profile.However,the reduction in the air flow rate from 125to 100slpm does not seem to affect the air temperature.As mentioned above,the measurements of air velocity and temperature serve as boundary conditions in mathematical models for melt blowing.27,28,36In the model results shown in this paper,air field measurements were used as boundary conditions.Figure 15shows online,experimental measurements of PP fiber diameter profiles for different polymer throughputs(whileFigure 6.Similar to Figure 5,except for a spinning speed of 800m/min.Figure 7.Similar to Figure 5,except for a spinning speed of 1000m/min.Figure 8.Similar to Figure 5,except for a spinning speed of 1200m/min.Figure 9.Similar to Figure 5,except for a spinning speed of 1500m/min.Figure 10.Similar to Figure 5,except for a spinning speed of 1750m/min.8740Ind.Eng.Chem.Res.,Vol.48,No.18,2009keeping the base conditions constant).High-speed flash pho-tography was used for these measurements.Figure 15shows that,for a higher mass throughput,the fiber diameter is larger at any position below the melt-blowing die.Figure 16shows the diameter predictions from the Marla and Shambaugh model 28for the base operating conditions.The heat-transfer correlations of both Kase and Matsuo 25and Marla et al.26were used in the model.The diameter profile from online measurements (a subset from Figure 15)is also plotted on the figure.For the region of rapid fiber attenuation,the first 5cm below the die,the choice of heat-transfer correlation does not greatly affect the model predictions of fiber diameter profile,and there is good agreement between experimental data and model predictions.Uyttendaele and Shambaugh 37obtained a similar result with an annular melt-blowing die.The choice of heat-transfer correlation is more evident in the prediction of the final fiber diameter.Figure 16lists the final diameters obtained by using the different heat-transfer correla-tions in the model.The final diameter obtained by an off-line experimental measurement of fiber diameter is also listed.As can be seen,use of the Marla et al.correlation gives a better estimate of final fiber diameter.Figure 17shows experimental measurements of fiber diameter at two different air flow rates.The air flow rate does not significantly affect the diameter profile,and this result parallels the findings from the experimental and modeling work of Marla and Shambaugh 28with slot dies.Figure 18shows the experi-mental temperature profiles obtained from online measurements at different polymer throughputs.The fiber temperature profiles show that larger fibers cool more slowly,and increased mass throughput increases the fiber temperature at any spinline position.At any spinline location,there are two effects which counter one another due to an increase in the mass flow rate of the polymer.The first effect involves the thermal inertia (mC p,f )of the fibers.With an increase in the polymer flow rate,the thermal inertia increases due to the increase in diameter (mass).The second effect is the increase of the fiber diameter and,hence,the increase of surface area available for heat transfer.Our experimental data indicate that the first effect is somewhat larger than the second for the heat-transfer process.Similar results were obtained by Bresee and Ko.18For the lowest polymer rate shown in Figure 18(0.75g/min),Figure 19shows predictions of the Marla model for both oftheFigure 11.Polybutylene results:model predictions of fiber temperature for melt spinning.Two different correlations for Nusselt number were tested in the model.Experimental data are also included forcomparison.Figure 12.Similar to Figure 11,except for a spinning speed of 1000m/min.Figure 13.Centerline air velocity below the melt-blowing die.The 60°slot die had a slot length of 7.46cm and an air gap of 0.65mm,and the die had a single polymer orifice.These data,which were taken with a Pitot tube,serve as boundary conditions in the melt-blowingmodel.Figure 14.Centerline air temperatue below the melt-blowing die.These data,which were taken with a fine thermocouple,serve as boundary conditions in the melt-blowing model.Ind.Eng.Chem.Res.,Vol.48,No.18,20098741heat-transfer correlations.As was observed previously,the model predictions made with the Kase and Matsuo correlation were higher than when the correlation of Marla et al.was used.Probably due to the modeling complexities for the melt-blowing process,the predicted temperature is not as close to the actual measured temperature compared to the closeness (of the predicted results to the experimental results)for the process of melt spinning.However,even for melt blowing,the correlation of Marla et al.is definitely more accurate than the correlation of Kase and Matsuo.For example,at 25cm below the die,the model predictions based on the heat-transfer correlation of Marla et al.is 118°C,while the prediction made with the Kase and Matsuo correlation is 190°C.At the same location the experimentally measured fiber temperature is 94°C.The reason the model predictions are high compared to experimental data may be due to the transverse vibratory motion of the fiber.It has been shown that,for heat transfer from wires to air in parallel flow,vibrations cause an increase in the heat-transfer co-efficient.24,38Even in melt spinning,Marla et al.28reported that the fiber exhibits transverse vibrations.However,these vibra-tions were quite low in amplitude compared to the vibrations observed in melt blowing.In an effort to more closely predictfiber temperature,future modeling of melt blowing may include the effects of vibration.The centerline air temperature is also shown in Figure 19.This temperature was measured with a thermocouple in the absence of polymer flow.It can be seen that the fiber remains warmer than the air for the first 25cm below the die.Figures 20and 21are similar to Figure 19,except that Figures 20and 21are for,respectively,polymer rates of 1.00and 1.25g/min.Increasing the polymer rate causes the predicted tem-perature profiles (with either correlation)to be higher.Figure 22,when compared with Figure 19,shows the effect of changing the air flow rate from 100to 125slpm.With either correlation,the predicted profiles are only slightly (a few degrees)lower for the 100slpm flow rate than for the 125slpm flow rate.ConclusionsOnline measurements of fiber diameter and temperature were made in the melt-spinning and melt-blowing processes.In melt spinning,the fibers seemed to cool slightly faster with an increase in spinning speed for both PP and PB.When theheat-Figure 15.Fiber diameter as a function of position below the die for the melt blowing of polypropylene.Data are shown for three different polymerrates.Figure 16.Model predictions of fiber diameter for the melt blowing of polypropylene.Two different correlations for Nusselt number were tested in the model.Experimental data are also included forcomparison.Figure 17.Fiber diameter as a function of position below the die for the melt blowing of polypropylene.Data are shown for two different air flowrates.Figure 18.Fiber temperature as a function of position below the die for the melt blowing of polypropylene.Data are shown for three different polymer rates.8742Ind.Eng.Chem.Res.,Vol.48,No.18,2009。

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Mettler Toledo 熔点测定系统 MP50 MP70 MP90 用户手册说明书

Mettler Toledo 熔点测定系统 MP50 MP70 MP90 用户手册说明书

T h e r m a l V a l u e E x c e l l e n ceExcellenceMelting Point Systems MP50MP70MP90Automatic Melting Point Determination Simple, Efficient and Video-Recorded2With the innovative METTLER TOLEDO melting point system, you are definitely on the safe side. You can determine the melting point or melting range very accurately. But the instru-ments can do a lot more: Investigate color changes, clear points and decomposition tem-peratures with video observation.Conformity with current standards Operation according to European and United States (USP) Pharma-copeias and the Japanese Indus-try Standard (JIS K0064) makes it easier to compare measurement values.The instrument provides two dif-ferent evaluation algorithms – the evaluation of a threshold value or the endpoint. In addition to the pharmacopeia mode, evaluations can also be performed thermody-namically. You can use capillaries with a diameter of up to 1.8 mm to ensure compliance with all standard methods.Unmolten substance immediate-ly after start of measurement While it is melting (meniscus point)Molten substance at end of melting (point C)Unmatched measurement principleAutomatic measurement of trans-mission and visual camera obser-vation in reflection guarantee that the melting points and melting ranges you determine are reliable.Measurements can include con- formity checks and printout of re-sults in one simple step.Alternatively, you can manually set evaluation points depending on the sample events that take place.Reliable resultsThe measurement principle and the possibility of eliminating obvious outliers from mean value determi-nation guarantee excellent repro-ducibility without the need to repeat the measurement.Statistical evaluation methods like averaging over several samples and standard deviation mean you can have full confidence in your data.Transmitted light picture which corresponds to the front light picture at end of meltingImage sequence of a meltingMelting Point Determination Trustworthy, Automatic, ExactM e l t i n g P o i n t D e t e r m i n a t i o n310080604020095 100 105 110 115 120 125 130 135The melting point and its detectionThe melting point is a characteristic property of a substance. It is the temperature at which the crystalline phase of a substance changes to the liquid state. A pure substance normally has a sharp melting point, whereas an impure substance melts over a temperature range that is lower than the melting point of the pure substance (melting point de-pression). Some organic compounds will however melt irreproducibly due to decomposition.Melting point determination is used in research and development as well as in quality control to identify and check the purity of a wide range of substances.If a sample is heated at a constant rate in a capillary, the transmission of light through the sample and hence the light intensity measured by a sensor (the camera) changes with increasing temperature. The sample is considered to have melted when a predefined level of light transmis-sion is reached.Intensity curve from transmitted light video versus tem-perature. The three marked points are start of melting A, threshold value B (here 20%) and end of melting C.Performance at a glance:• One Click ™ and superior ergonomics – quick to learn, easy to operate• Convenient playback of high resolution color videos – offers maximum security • Simultaneous measurement of up to 6 samples – increases productivity • Compliant to standards – ensures trustworthy resultsTemperature in °C4S i m p l eDetermine the Melting Pointwith just One Click™• One Click ™ Melting Point • Fatigue-free Analyses • Easy to useOne Click ™ resultsMelting point determination has never been so easy!The color touch screen allows one finger intuitive operation, provides clear information for the user, and can be easily seen from a distance. Just One Click ™ is all that is need-ed to start the measurement – the instrument does the rest for you. While the measurement is being performed, you can attend to other important tasks.Superior ergonomicsHigh priority was given to thought-ful instrument design to ensure optimum ergonomics. Features like a small instrument footprint, color touch screen and rotatable protec-tion lid are distinct advantages re-sulting from this unique concept.This enables you to perform mea-surements very easily without experiencing fatigue. In addition, you can conveniently set any one of several different languages and work in your own native tongue.Intuitive operationThe operating concept is fast and easy to understand and offers sim-ple operating routines.It provides the same ease of use as other innovative METTLER TOLEDO laboratory instruments.In “Manual method”, set the start and end temperatures and heating rate according to the method in the Pharmacopeia. Insert the capillaries and start the measurement.The MP50 start screen. The pharmaco-peia operating mode has been set. Once programmed the shortcut key “Urea” could be used to start the measurement immediately.For sample preparation the dry powdery substance is ground in a mortar and filled into the capillaries, which are then insert-ed into the furnace.The following sequence of images illustrates a typical analysis5Simple determination of identity and purityA standard procedure used in the pharmaceutical industry to identify starting materials is the determination of melting temperatures.With the MP50 melting point system, you can test organic solids with a defined melting point up to a maximum temperature of 300 °C. The instrument provides a rapid and exact method for automatic, unat-tended melting point determination.Fill capillaries with the reference substance, the substance under inves-tigation and a mixture of the two substances.A melting point depression observed even if the purity level is only slightly different guarantees that substances are correctly identified.When melting is completed, the instru-ment signals the end of the measurement with an acoustic tone and displays themeasured temperatures.Scan the QR code with a smart phone and enjoy one-click-melting.6High Quality Sample Observation Maximizes Sample Information• High resolution color videos • Replay on the instrument• Comprehensive documentationWatch every single crystal melt High resolution color videos allow you to study melting effects even with substances that are colored or decompose. You can also detect thermochromic effects.With more than 6x zoom, one can obtain detailed information on the behavior of very small samples.This is of great value, especially in the research and development of fine and specialty chemicals and for the characterization of new pharmaceutically active sub-stances.This melting point system satisfies the requirements of standard meth-ods that need visual observation.Easy to check resultsNever miss a melting point again. Unattended measurements do not result in loss of visual data. The high resolution color videos can be repeatedly replayed on the instru-ment. This allows you to check un-expected results by visually review-ing measurements.The instrument shows the video, intensity curve and results on a full VGA color screen in high resolution.Decomposing substance, right ones undecomposedThermochromic transition Colored substanceMaximum informationGet the maximum information pos-sible from your measurements. The MP70 fulfills this need and offers easy data archiving. Video files can be easily transferred to the com-puter as standard AVIs via an SD memory card.Thus, there is no limit to the num-ber of videos you can archive. Replay is possible with commonly available video software.C o n v e n i e n t V i d e o P l a y B a c k7Secure characterization of precious substancesIn chemical synthesis laboratories, newly synthesized substances have to be quickly and accurately characterized. This is routinely done by determining the melting point. Nothing must be left to chance because the substances are usually only present in very small amounts and are therefore very precious.The magnified visual observation opens up new dimensions in sample analysis.The measurement is not lost if automatic evaluation did not determine a melting point due to the behavior of the substance or poor sample preparation. A correct value can still be obtained by replaying the video and eliminating any outliers from the statistical results.Air bubbles8Increased EfficiencyThrough Simultaneous Determination• Efficient measurement and documentation • Intelligent method management • Optimized handlingMeasure rapidly and economicallyYou can achieve high throughput by simultaneously determining up to 6 samples in one run. One Click ™ enables you to start quickly after sample preparation.Short heating and cooling times allow you to perform more analy-ses in the same amount of time.The storage of results as a PDF file or by exporting as an ASCII text file ensures data security.Flexible and adaptable methods Perform different measurement tasks rapidly and efficiently by working with up to 60 stored meth-ods. These include simple cali-bration routines that ensure your instrument is performing properly. Easily check your product for con-formity using the substance data-base that is incorporated within the instrument. This convenient feature allows you to add your own sub-stances and acceptable tempera-ture limits.Simplified Sample Handling Rapid sample preparation and quick sample insertion can help you to save time and money. An innovative sample preparation tool specially developed for the Excellence melting point systems holds up to six samples. This sim-plifies the correct filling, storage and simultaneous insertion of multiple capillaries.Rapid sample preparationContributions to efficiency increaseData output E f fi c i e n t9High throughput analysisA quality control laboratory might have to determine the melting points of up to 25’000 samples in a year.In this case, the MP90 melting point instrument offers unique possibilities for saving time and money in the routine analysis of substances.Faster sample handling using the sample preparation tool, one click op-eration, and twice the usual number of samples measured simultaneously – these unique advantages offer a real and effective reduction in analysis time when compared with other instruments.The numerous possibilities for reporting results, whether on a strip- or Eth-ernet printer, by creating PDF files or exporting text files, together with the user identification system guarantee a high level of data security and a working environment conforming to GLP .One Click ™10M o d e l O v e r v i e wAlways the Right System for Your RequirementsThe METTLER TOLEDO product portfolio for melting point determination consists of three different systems. The table below illustrates the incremental difference between the models.MP50 – Simply to the pointEverything you need for automatic melting point determination.• 4 samples can be measured in parallel• Gray scale display of up to 30 minutes of video • Replay on the instrument • 12 One Click ™ Short Cuts • User identification• Optional IQ/OQ availableMP70 – best choice for maximum flexibilityAdditional possibilities through optimum visual observation • Color video recording of up to 300 minutes in length• 2 manually set evaluation points • Export possibilities on an exter-nal SD card• 12 One Click ™ per user• Memory for up to 20 user-defined methods• 5 substances in reference database• Automated calibration procedure • PDF storage on a USB flash drive or direct transfer to a PC• GMP-compliant access control • LabX ® 2012 PC Software connectivityMP90 – melting pointdetermination at the highest level Optimized for a wide range of tasks and high throughput• 6 samples can be measured in parallel• Wide temperature range from room temperature to 400 °C • Last 100 results are stored internally• 60 methods can be stored • 5 pre-programmed methods• Reference database incorporated for up to 100 substances • Direct transfer of PDFs and videos to a PC• Modern connections: USB and Ethernet• Delivered with comprehensive accessories• LabX ® 2012 PC Software connectivityApplication MP50MP70MP90Melting point •••Melting range •••Purity determination •••Decomposition temperature ••Solvent loss ••Sublimation••Change in the crystal structure ••Sintering point ••Color change ••Thermochromism ••High throughput analysis•Application table• suitable, partly suitableSolutions powered by LabX ®LabX ®Comparison Table Excellence Melting Point SystemsMP70/one-click-meltingWhatever the TaskWe have the Right AnswerMETTLER TOLEDO manufactures a wide array of solutions for routine applications, quality assurance, and research and development. This is supported by competent assis-tance, extensive applications know-how and innovative accessories.Density and refractive indexFrom simple portable meters to fully automatic multi-parameter systems, METTLER TOLEDO offers flexible solutions for density and refractive index measure-ments in the laboratory and on site.Halogen moisture InstrumentsThe METTLER TOLEDO halogen moisture instruments are made for fast and reliable moisture analysis in laboratory and production environments. TitratorsThe Excellence family of titrators provides highly au-tomated state-of-the-art solutions for a wide range of routine to complex titrations and Karl Fischer moisture content determination.Pipettes, Tips and ServicesRAININ is the leading provider of advanced liquid handling solutions for scientists worldwide.Thermal analysisComplete range (DSC, TGA, TMA and DMA) of innova-tive, modular thermal analysis systems for almost any task in materials characterization.For more informationMettler-Toledo AG, AnalyticalCH-8603 Schwerzenbach, Switzerland Tel. +41 44 806 77 11Fax +41 44 806 72 40Subject to technical changes© 07/2012 Mettler-Toledo AG, 51725147B Marketing AnaChem / MarCom AnalyticalQuality certificate. Development, production and testing according to ISO 9001.Environmental management system according to ISO 14001.“European conformity”. The CE conformity mark provides you with the assurance thatour products comply with the EU directives.。

VEGAWELL 52 压力测量仪器说明书

VEGAWELL 52 压力测量仪器说明书

C ontentsC ontents1D escription of the measuring principle (3)2T ype overview (4)3M ounting instructions (5)4E lectrical connection4.1G eneral requirements (7)4.2P ower supply (7)4.3C onnection cable (7)4.4C able screening and grounding (7)4.5W iring plan VEGAWELL52-4...20m A (7)4.6W iring plan VEGAWELL52-4...20m A/HART-P t100. (8)5O peration5.1O verview (9)5.2A djustment with PACT ware (9)6T echnical data (10)7D imensions (14)8P roduct code (15)T ake note of safety instructions for E x applicationsP lease note the E x specific safety information which you canfind on our homepage \services\downloads and which comes with every instrument.I n hazardous areas you should take note of the appropriate regulations,conformity and type approval certificates of the sensors and power supply units.T he sensors must only be operated on intrinsically safe circuits.T he permissible electrical values are stated in the certificate.35400-EN-0901301D escription of the measuring principleM easuring principleVEGAWELL 52pressure transmitters work according to the hy -drostatic measuring principle ,which functions independently of the dielectric properties of the product and is not in fluenced by foam generation .T he sensor element of VEGAWELL 52is the dry ceramic -capaci -tive CERTEC ®measuring cell in two sizes .B ase element and diaphragm consist of high purity sapphire -ceramic ®.T he hydrostaticpressure of the product causes via the diaphragm a capacitance change in the measuring cell .T his capacitance change is converted into an appropriate output signal .F ig .1:C on figuration of the CERTEC measuring cell with VEGAWELL 521D iaphragm2S oldered glass bond 3B ase elementT he advantages of the CERTEC ®measuring cell are :l V ery high overload resistance l N o hysteresisl E xcellent long -term stabilityl C ompletely front flush installation l G ood corrosion resistance l V ery high abrasion resistance W ide application rangeVEGAWELL 52is suitable for level measurement in deep wells and ballast tanks as well as for gauge measurement in open flumes .T ypical media are drinking water and waste water as well as water containing abrasive substances .A ll signal outputs are available in 4…20m A and 4…20m A /HART -P t 100.I n the 4…20m A /HART -P t 100version ,a temperature sensor P t 100in four -wire technology is integrated in the transducer .P ower supply or processing are carried out via an external tem -perature transducer .35400-E N -0901302T ype overviewVEGAWELL52M easuring cell :CERTEC ®M edia :drinking water and waste waterP rocess fitting :S training clamp ,screw connection ,threadM aterial process fitting :316LM aterial ,suspension cable :PE ,PUR ,FEP M aterial transmitter :316L ,1.4462(D uplex ),each also with PE coating ,PVDF ,T itaniumD iameter transmitter :depending on material and version at least 22mmM easuring range :0…0.1bar up to 0…25bar P rocess temperature :-20…+80°C (-4…+176°F )D eviation :<0.2%,<0.1%S ignal output :4…20m A ,4…20m A /HARTO peration :depending on the version via PACT ware /PC35400-EN -0901303M ounting instructionsM ounting positionT he following illustration shows a mounting example for VEGA -WELL 52.T he VEGA price list contains suitable mounting brack -ets under the section A ccessories .W ith these parts ,standard mounting arrangements can be realised quickly and reliably.F ig .3:VEGAWELL 52in a pump shaft with VEGABOX 02VEGAWELL 52must be mounted in a calm area or in a suitable protective tube .T his avoids lateral movements of the transmitter and the resulting corruption of measurement data.N ote :A s an alternative to fixing the transmitter ,the use of a measuring instrumentholder from VEGA 's line of mount -ing accessories is recommended .B eside the connection and suspension cables ,the suspension cable also contains a capillary for atmospheric pressure compen -sation .A ll versions can be shortened on site .W ith VEGAWELL 52,the electronics is completely integrated in the transmitter .T he cable end can be lead directly to a dry con -nection compartment .P ressure compensation is then carried out via the filter element of the capillaries.N ote :T he pressure compensation housing VEGABOX 02is recommended for connecting VEGAWELL 52.I t contains a high -quality ventilation filter and terminals .A protec -tive cover is optionally available for use outdoors .M ounting versionsT he following illustrations show the di fferent mounting versions depending on the instrument type .M ounting with straining clampF ig .5:S training clamp 1S uspension cable 2S uspension opening 3C lamping jawsM ounting with screw connectionF ig .6:S crew connection 1S uspension cable 2Seal screw 3C one bushing 4S eal cone5S crew connection 6S eal35400-E N -090130M ounting with housing and thread231F ig .7:H ousing with threadG 1½A 1H ousing 2S eal 3T hread35400-EN -0901304E lectrical connection4.1G eneral requirementsT he supply voltage range can di ffer depending on the instrument version .Y ou can find exact speci fications in chapter "T echnical data ".T he national installation standards as well as the valid safety regulations and accident prevention rules must be observed .I n hazardous areas you should take note of the appro -priate regulations ,conformity and type approval certi fi-cates of the sensors and power supply units .4.2P ower supplyS upply voltage and current signal are carried on the same two -wire cable .T he requirements on the power supply are speci fied inchapter "T echnical data ".T he VEGA power supply units VEGATRENN 149AE x ,VEGAS -TAB 690,VEGADIS 371as well as VEGAMET signal condition -ing instruments are suitable for power supply .W hen one of these instruments is used ,a reliable separation of the supply circuits from the mains circuits according to DIN VDE 0106part 101is ensured .4.3C onnection cableI n generalA n outer diameterof 5…9mm ensures the seal e ffect of the cable entry .I f electromagnetic interference is expected ,screened ca -ble should be used for the signal lines .T he sensors are connected with standard two -wire cable without screen .I n E x applications ,the corresponding installation regu -lations must be noted for the connection cable .4.4C able screening and groundingI f screened cable is necessary ,the cable screen must be con -nected on both ends to ground potential .I f potential equalisation currents are expected ,the connection on the evaluation side must be made via a ceramic capacitor (e .g .1n F ,1500V ).4.5W iring plan VEGAWELL 52-4…20m AD irect connectionF ig .8:W ire assignment ,suspension cable1blue (-):to power supply or to the processing system 2brown (+):to power supply or to the processing system 3S hielding4B reather capillaries with filter elementC onnection via VEGABOX 02F ig .9:T erminal assignment VEGABOX 021T o power supply or the processing system2S hielding1)C onnection viahousingF ig .10:T erminal assignment of the housing1T o power supply or the processing system2S hielding2)1)C onnect screen to ground terminal .C onnect ground terminal on the outside of the housing as prescribed .T he two terminals are galvanically connected .2)C onnect screen to ground terminal .C onnect ground terminal on the outside of the housing as prescribed .T he two terminals are galvanically connected .35400-E N -0901304.6W iring plan VEGAWELL52-4…20m A/HART-P t100D irect connectionF ig.11:W ire assignment,connection cable1blue(-):to power supply or to the processing system2B rown(+):to power supply or to the processing system3W hite:for processing of the integrated P t100(power supply)4Y ellow:for processing of the integrated P t100(measurement)5R ed:for processing of the integrated P t100(measurement)6B lack:for processing of the integrated P t100(power supply)7S hielding8B reather capillaries withfilter elementC onnection via VEGABOX02F ig.12:T erminal assignment VEGABOX021T o power supply or the processing system(signal pressure transmitter)2T o power supply or the processing system(connection cables resistance ther-mometer P t100)3S hielding3)C onnection via VEGABOX02with integrated temperaturesensorF ig.13:T erminal assignment VEGABOX021T o power supply or the processing system(signal pressure transmitter)2F or voltage supply or to processing system(resistance thermometer P t100) 3S hielding4)C onnection viahousingF ig.14:T erminal assignment of the housing1T o power supply or the processing system(signal pressure transmitter)2F or voltage supply or to processing system(resistance thermometer P t100) 3S hielding5)3)C onnect screen to ground terminal.C onnect ground terminal on the outside of the housing as prescribed.T he two terminals are galvanicallyconnected.4)C onnect screen to ground terminal.C onnect ground terminal on the outside of the housing as prescribed.T he two terminals are galvanicallyconnected.5)C onnect screen to ground terminal.C onnect ground terminal on the outside of the housing as prescribed.T he two terminals are galvanicallyconnected.35400-EN-0901305O peration5.1O verviewVEGAWELL524…20m AVEGAWELL52-4…20m A has no adjustment options.VEGAWELL524…20m A/HART-P t100l A djustment software according to FDT/DTM standard,e.g.PACT ware and PCl HART handheld5.2A djustment with PACT wareC onnecting the PC to the signal cable6T echnical dataM aterials and weightsM aterials ,wetted parts -T ransmitter 316L ,316L with PE coating ,1.4462(D uplex ),1.4462with PE coating ,PVDF ,T itanium-D iaphragmsapphire ceramic ®(99.9%oxide ceramic )-M easuring cell sealFKM (VP 2/A )-FDA and KTW approved ,FFKM (P erlast G 75S ),EPDM (A +P 75.5/KW 75F )-S uspension cablePE (FDA and KTW -approved ),FEP ,PUR -C able gland on the transmitter 316L -P rocess fitting 316L -S training clamp1.4301-U nassembled screw connection 316L ,PVDF -T hreaded connection on the housing 316LM aterials ,non -wetted parts -H ousing plastic PBT (P olyester ),316L W eight approx .-B asic weight0.8kg (1.764lbs )-S uspension cable 0.1kg /m (0.07lbs /ft )-S training clamp 0.2kg (0.441lbs )-S crew connection 0.4kg (0.882lbs )-P lastic housing0.8kg (1.764lbs )-S tainless steel housing1.6kg (3.528lbs )I nput variableM easured value L evelM easuring rangesee product code R ecommended max .turn down10:1O utput variable4…20m A O utput signal4…20m AS ignal resolution 2µA F ailure signal<3.6m A M ax .output current 22m A R un -up time2sS tep response time100ms (ti :0s ,0…63%)F ul filled NAMUR recommendations NE 434…20m A /HART -P t 100O utput signal4…20m A /HARTS ignal resolution 2µAF ailure signal<3.6m A ;20.5m A ;22m A ;unchanged (adjustable via PACT ware )M ax .output current 22m A R un -up time15sS tep response time200ms (ti :0s ,0…63%)F ul filled NAMUR recommendationsNE 43A dditional output parameter -temperatureintegrated resistance thermometer P t 100according to DIN EN 60751R ange -50…+100°C (-58…+212°F )R esolution1°KD eviation for 4…20m A version 6)S peci fications refer to the set span .T urn down (TD )=nominal measuring range /set span .D eviation with version <0.2%-T urn down 1:1up to 5:1<0.2%-T urn down >10:1<0.04%xTD6)D etermined according to the limit point method according to IEC 60770,incl .non -linearity ,hysteresis and non -repeatability .35400-EN -090130D eviation with version <0.1%-T urn down 1:1up to 5:1<0.1%-T urn down >10:1<0.02%x TDD eviation for version 4…20m A /HART -P t 1007)A pplies to digital HART interface as well as to analogue current output 4…20m A .S peci fications refer to the set span .T urn down (TD )is the relation nominal measuring range /set span .D eviation with version <0.2%-T urn down 1:1up to 5:1<0.2%-T urn down >10:1<0.04%x TD D eviation with version <0.1%-T urn down 1:1up to 5:1<0.1%-T urn down >10:1<0.02%x TDI n fluence of the product or ambient temperatureA pplies to digital HART interface as well as to analogue current output 4…20m A .S peci fications refer to the set span .T urn down (TD )is the relation nominal measuring range /set span .A verage temperature coe fficient of the zero signalI n the compensated temperature range of 0…+80°C (+32…+176°F ),reference temperature 20°C (68°F ).A verage temperature coe fficient of the zero signal -T urn down 1:1<0.05%/10K -T urn down 1:1up to 5:1<0.1%/10K -T urn down >10:1<0.15%/10KO utside the compensated temperature range A verage temperature coe fficient of the zero signal -T urn down 1:1typ .<0.05%/10K L ong -term stability (similar to DIN 16086,DINV 19259-1and IEC 60770-1)A pplies to digital HART interface as well as to analogue current output 4…20m A .S peci fications refer to the set span .T urn down (TD )is the relation nominal measuring range /set span .L ong -term drift of the zero signal<(0.1%x TD )/yearA mbient conditionsA mbient temperature -C onnection cable PE-40…+60°C (-40…+140°F )-C onnection cable PUR ,FEP -40…+85°C (-40…+185°F )S torage and transport temperature-20…+80°C (-4…+176°F )P rocess conditionsP rocess pressureM ax .process pressure ,transmitter 8)-M easuring range 0.1bar (1.45psig )15bar (218psig )-M easuring range 0.2bar (2.9psig )20bar (290psig )-M easuring range ≤0.4bar (5.8psig )25bar (363psig )P ressure stage ,process fitting -U nassembled screw connection 316L :PN 3,PVDF :unpressurized -T hread on the housingPN 3P roduct temperature ,depending on the version7)D etermined according to the limit point method according to IEC 60770,incl .non -linearity ,hysteresis and non -repeatability .8)L imited by the overpressure resistance of the measuring cell .35400-E N -090130S uspension cable T ransmitter P roduct temperature PE A ll -20…+60°C (-4…+140°F )PUR A ll -20…+80°C (-4…+176°F )PUR PE coating -20…+60°C (-4…+140°F )FEP A ll -20…+80°C (-4…+176°F )FEPPE coating-20…+60°C (-4…+140°F )V ibration resistancemechanical vibrations with 4g and 5…100H z 9)E lectromechanical dataS uspension cable -C on figurationsix wires ,one suspension cable ,one breather capillary ,screen braiding ,foil ,mantle-T ensile strength ≥1200N (270pound force )-M ax .length1000m (3280ft )-M in .bending radius 25mm (with 25°C /77°F )-D iameter approx .8mm (0.315in )-colour (non -E x /E x )-PEblack /blue -colour (non -E x /E x )-PUR ,FEP blue /blueC able entry housing or VEGABOX 021x cable gland M 20x 1.5(cable :ø5…9mm ),1x blind stopper M 20x 1.5S crew terminalsfor wire cross section 1.5mm ²(AWG 16),screen up to 4mm ²(AWG 12)S upply voltage -4…20m AO perating voltage8…36V DC P ermissible residual ripple -<100H zU ss <1V -100H z …10k H z U ss <10m V L oadsee diagram1V oltage limit2O perating voltageS upply voltage -4…20m A /HART -P t 100O perating voltage9.6…36V DCP ermissible residual ripple -<100HzU ss <1V -100H z …10k H z U ss <10m V L oadsee diagram9)T ested according to the regulations of G erman L loyd ,GL directive 2.35400-EN -0901301HART load 2V oltage limit3O perating voltageE lectrical protective measuresP rotection -T ransmitter IP 68(30bar )-H ousingIP 66/IP 67-VEGABOX 02IP 65O vervoltage category III P rotection classIIIE xisting approvals or approvals applied forG as explosion protection e .g .according to ATEX and IEC F ire -damp protection e .g .according to ATEX O ver fill protection e .g .according to WHGS hip approvale .g .according to GL ,LRS ,ABS ,RINAT he available approvals can be selected via the con figurator on www .vega .com .D epending on the version ,instruments with approvals can have di fferent technical data .F or these instruments ,please note the corresponding approval documents .T hey can be downloaded in the download section on www .vega .com .CE conformityEMC (2004/108/EG )EN 61326-1:2006LVD (2006/95/EG )EN 61010-1:2001E nvironmental instructionsVEGA environment management systemcerti fied according to DIN EN ISO 14001Y ou can find detailed information under www .vega .com .35400-E N -0901307D imensionsVEGAWELL52-suspension cable1F ig.18:VEGAWELL52-suspension cable1T ransmitter D uplex,with straining clamp2T ransmitter D uplex for deep wells,with unassembled screw connection G1½A(1½NPT)and closing cap3T ransmitter D uplex,with PE coating4T ransmitter with screwed connection of PVDF5T ransmitter T itanium/T itaniumwith glass leadthrough,with thread G1A(1NPT)and plastic housingVEGAWELL52-suspension cable2F ig.20:VEGAWELL52-suspension cable1T ransmitter316L,with straining clamp2T ransmitter T itanium,with unassembled screw connection G1A(1NPT)VEGAWELL52-threadedfittingF ig.22:VEGAWELL52-thread1T hreadedfitting G½inner G¼2T hreadedfitting G135400-EN-0901308P roduct codeVEGAWELL 52Approval XX withoutXM Ship approvalAX ATEX II 2G EEx ia IIC T6AM ATEX II 2G EEx ia IIC T6 + Ship approval AI IEC Ex ia IIC T6Fastening / Material X4withoutA4Straining clamp / 1.4301(304)GA Threaded fitting, unassembled G1½A PN3 / 316L NP Threaded fitting, unassembled G1½A PN0,2 / PVDF GC Threaded fitting, unassembled G1A PN3 / 316L GK Thread G1½A PN3 / 316L with plastic housingGV Thread G1½A PN3 / 316L w.hous. StSt (precision casting)Version / Process temperature A Suspension cable PE / -20...60°C D Suspension cable PUR / -20...80°C B Suspension cable FEP / -20...80°C LengthK 6 m suspension cable PE L 12 m suspension cable PE M 27 m suspension cable PET individually selectable length (PE/PUR/FEP)Transmitter material / Diameter D Duplex 1.4462 / 32mm V 316L / 22mmK Duplex 1.4462 with PE coating / 35mm P PVDF / 44 mmSeal measuring cell 1FKM (VP2/A)3EPDM (A+P 75.5/KW75F)P FFKM (Perlast G75S)Measuring rangeA rel. / 0...0.1 bar (0...10 kPa)B rel. / 0...0.2 bar (0...20 kPa)C rel. / 0...0.4 bar (0...40 kPa)D rel. / 0...1 bar (0...100 kPa)E rel. / 0...2.5 bar (0...250 kPa)F rel. / 0...5 bar (0...500 kPa)G rel. / 0...10 bar (0...1000 kPa)2abs. 0...2.5 bar (0...250kPa)3abs. 0...5.0 bar (0...500kPa)Electronics C 4...20mAD 4...20mA/HART® + PT100 4-wire Deviation in characteristic 10.2020.10Transmitter options X withoutV for deep wellsWL52.35400-E N -090130VEGA G rieshaber KG A m H ohenstein 11377761S chiltach G ermanyP hone +49783650-0F ax +49783650-201E -M ail :info @de .vega .com www .vega .comY ou can find at www .vega .com downloads of the followingl operating instructions manuals l menu schematics l software l certi ficates l approvalsand much ,much moreS ubject to change without prior notice 35400-EN -090130。

透射电子显微镜TEM

透射电子显微镜TEM

现代分析方法与技术
透射电子显微镜
Transmission Electron Microscopy
目录 CONTENTS
1 2 3 4
历史 History 原理 Background 结构 Components
制备 Preparation
应用 Application
5
2 透射电子显微镜
历史 HISTORYBiblioteka 2形制 Shapes
field will cause electrons to move according to the left hand rule
热电子发射 或 场电子发射 thermionic or field electron emission
• Hairpin-style filament
5 透射电子显微镜
目录 CONTENTS
1 2 3 4
历史 History 原理 Background 结构 Components
制备 Preparation
应用 Application
5
6 透射电子显微镜
原理 BACKGROUND
电子 ELECTRON
光学显微镜所能达到的最大分辨率受到以下条件的限制
IG Farben-Werke
The De Broglie wavelength of electrons was many orders of magnitude smaller than that for light, theoretically allowing for imaging at atomic scales 1936 改进 TEM 的成像效果，尤其是对生物样品的成像
• Small spike-shaped •使用磁场可以形成 不同聚焦能力的磁透镜
Processing and properties of magnesium containing

Processing and properties of magnesium containing


Magnesium is a light metal, with a density two-thirds that of aluminium, is abundant on Earth and is biocompatible; it thus has the potential to improve energy efficiency and system performance in aerospace, automobile, defence, mobile electronics and biomedical applications1–5. However, conventional synthesis and processing methods (alloying and thermomechanical processing) have reached certain limits in further improving the properties of magnesium and other metals6. Ceramic particles have been introduced into metal matrices to improve the strength of the metals7, but unfortunately, ceramic microparticles severely degrade the plasticity and machinability of metals7, and nanoparticles, although they have the potential to improve strength while maintaining or even improving the plasticity of metals8,9, are difficult to disperse uniformly in metal matrices10–14. Here we show that a dense uniform dispersion of silicon carbide nanoparticles (14 per cent by volume) in magnesium can be achieved through a nanoparticle self-stabilization mechanism in molten metal. An enhancement of strength, stiffness, plasticity and high-temperature stability is simultaneously achieved, delivering a higher specific yield strength and higher specific modulus than almost all structural metals. We describe a processing method of achieving a uniform dispersion of dense silicon carbide (SiC) nanoparticles in magnesium (Mg) matrix (see Methods and Extended Data Fig. 1). Ingots of Mg6Zn (1 vol% SiC) were first obtained. At this stage, the nanoparticles were mostly distributed along the grain boundary region owing to the pushing of nanoparticles by the solidification front15. Previous work showed that a higher drag force in the melt via dense nanoparticles (for example, >​ 6 vol%) could promote nanoparticle engulfment16. Typically, a low volume fraction of nanoparticles can be uniformly dispersed by ultrasonic processing, but this is not effective for dispersing dense nanoparticles16. Therefore, nanoparticles were concentrated by evap­ orating away magnesium and zinc from the Mg6Zn (1 vol% SiC) ingot at 6 torr in a vacuum furnace. After evaporation and slow cooling at approximately 0.23 K s−1, a sample with about 14 vol% nanoparticles in an Mg2Zn matrix was obtained. We first characterized the distribution and dispersion of SiC nano­ particles in as-solidified magnesium samples using scanning and transmission electron microscopy (SEM, TEM). To clearly reveal the nanoparticles, the SEM samples were cleaned by low-angle ion mill­ ing (10°, to remove the nanometre-sized polishing powders) and then slightly etched by gallium ions (90°, to preferentially etch the magne­ sium matrix) using a focused ion beam (FIB). SEM images in Fig. 1a and b were acquired at a 52° tilt to expose the nanoparticles on the surface of the magnesium matrix. This high volume fraction of nanoparticles is uniformly distributed and dispersed in the magnesium matrix, as shown in Fig. 1a and b. This uniform dispersion of nano­ particles in the magnesium matrix is also confirmed by TEM analysis