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e-mail:**************For latest product manuals:User’s GuideKH, KHR, KHLV SERIESKapton ®Flexible HeatersShop online atGENERAL DESCRIPTIONOMEGALUX®Kapton®Insulated Flexible Heaters are available in avariety of shapes, sizes, and wattages. Wattage ratings are 2.5, 5, or 10W/in2at 115 or 28 volts. Kapton offers a high degree of resistance tochemicals, and has excellent outgasing properties in high vacuumenvironments. KH models are rectangular 115 volt units; KHLV modelsare rectangular 28 volt units, and KHR models are round 115 volt units.Contact OMEGA sales Department for specific part numbers:800-872-9436Typical construction consists of an etched foil element of 0.0005" or0.0001" thickness, which is encapsulated between two layers of 0.002"Kapton and 0.001 FEP TefIon®adhesive. Lead wires exit from theupper-right hand corner of width (W) side of heater. For 0.50" rind 1.00"wide heaters only, leads exit centrally from width (W) side. Leads exitround heaters radially. Pressure sensitive adhesive (PSA) is available asart option on heaters rated at 2.5 or 5 W/in2. The heaters can also bemechanically clamped or epoxy mounted by the user.*Kapton and Teflon are registered trademarks of DuPont.SPECIFICATIONSHeating Element Design:Etched circuit.Operating Temperature:-328°F to 392°F (-200°C to 200°C) forheaters without pressure sensitiveadhesive (PSA). Maximum operatingtemperature for heaters withpressure sensitive adhesive is 250°F(120°C)Voltage:KH, KHR Series: 115 Volts KHLVSeries: 28 VoltsWatt Density: 2.5, 5, or 10 W/in2Pressure Sensitive Optional. not available at 10Adhesive (PSA):watts/square inch watt densityLead Wire:12" of Teflon Insulated(MIL W-16878) lead wire(wire gauge varies with heater) Dielectric Strength:1260 VacMinimum Sending Radius:0.032"Heater Thickness:0.010" except at lead wife exit(thickness varies with heater)INSTALLATION AND OPERATIONUse a method of temperature control (e.g., thermostat,thermocouple and temperature controller, or variablevoltage transformer) to prevent heaters from exceedingmaximum operating temperature ratings. Place temperaturesensor close enough to the heater to sense heatertemperature.1. DO NOT immerse heaters in liquids.2. DO NOT operate heaters at a voltage higher than the specified orrated voltage.3. DO NOT cut, punch holes in or otherwise mishandle heaters.4. AVOID exposing heaters to chemicals, acids, alkalies. oils fluids orother substances that could ignite or cause damage to the heaters.5. DO NOT insulate heaters unless adequate measures are taken tocontrol heater temperature.6. DO NOT leave heaters operating unattended unless adequatecontrols are installed to insure safety.7. Heaters can be bent around curved surfaces; however, DO NOTexceed minimum banding radius.8. Exercise care in attaching heaters to flat or curved surfaces. Heaterscan be attached by mechanical clamping, by using factory appliedpressure sensitive adhesive (PSA), or with a thin layer of conductiveepoxy. Make sure that the entire heater is in contact with the surfacewith no air pockets trapped underneath. This is especially importantfor high watt density heaters, i.e. heaters with a watt density of 10watts/square inch, to prevent heater failure. DO NOT overlapheaters.9. Heaters must be attached to an appropriate heat sink and shouldNOT be mounted free-standing In air.10. Make sure heaters are installed and used by qualified personnel.DO NOT attempt to repair damaged heaters.It is the policy of OMEGA Engineering, Inc. to comply with all worldwide safety and EMC/EMI regulations that apply. OMEGA is constantly pursuing certification of its products to the European New Approach Directives. OMEGA will add the CE mark to every appropriate device upon certification.The information contained in this document is believed to be correct, but OMEGA accepts no liability for any errors it contains, and reserves the right to alter specifications without notice.WARNING: These products are not designed for use in, and should not be used for, human applications.WARRANTY/DISCLAIMEROMEGA ENGINEERING, INC. warrants this unit to be free of defects in materials and workmanship for a period of 13 months from date of purchase. OMEGA’s WARRANT Y adds an additional one (1) month grace period to the normal one (1) year product warranty to cover handling and shipping time. T his ensures that OMEGA’s customers receive maximum coverage on each product.If the unit malfunctions, it must be returned to the factory for evaluation. OMEGA’s Customer Service Department will issue an Authorized Return (AR) number immediately upon phone or written request. Upon examination by OMEGA, if the unit is found to be defective, it will be repaired or replaced at no charge. OMEGA’s WARRANTY does not apply to defects resulting from any action of the purchaser, including but not limited to mishandling, improper interfacing, operation outside of design limits, improper repair, or unauthorized modification. This WARRANTY is VOID if the unit shows evidence of having been tampered with or shows evidence of having been damaged as a result of excessive corrosion; or current, heat, moisture or vibration; improper specification;misapplication; misuse or other operating conditions outside of OMEGA’s control. Components in which wear is not warranted,include but are not limited to contact points, fuses, and triacs.OMEGA is pleased to offer suggestions on the use of its various products. However, OMEGA neither assumes responsibility for any omissions or errors nor assumes liability for any damages that result from the use of its products in accordance with information provided by OMEGA, either verbal or written. OMEGA warrants only that the parts manufactured by the company will be as specified and free of defects. OMEGA MAKES NO OTHER WARRANTIES OR REPRESENTATIONS OF ANY KIND WHATSOEVER, EXPRESSED OR IMPLIED, EXCEPT THAT OF TITLE, AND ALL IMPLIED WARRANTIES INCLUDING ANY WARRANTY OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE HEREBY DISCLAIMED. LIMITATION OF LIABILITY: The remedies of purchaser set forth herein are exclusive, and the total liability of OMEGA with respect to this order, whether based on contract, warranty, negligence, indemnification, strict liability or otherwise, shall not exceed the purchase price of the component upon which liability is based. In no event shall OMEGA be liable for consequential,incidental or special damages.CONDITIONS: Equipment sold by OMEGA is not intended to be used, nor shall it be used: (1) as a “Basic Component” under 10 CFR 21 (NRC), used in or with any nuclear installation or activity; or (2) in medical applications or used on humans. Should any Product(s)be used in or with any nuclear installation or activity, medical application, used on humans, or misused in any way, OMEGA assumes no responsibility as set forth in our basic WARRANTY/DISCLAIMER language, and, additionally, purchaser will indemnify OMEGA and hold OMEGA harmless from any liability or damage whatsoever arising out of the use of the Product(s) in such a manner.RETURN REQUESTS /INQUIRIESDirect all warranty and repair requests/inquiries to the OMEGA Customer Service Department. BEFORE RET URNING ANY PRODUCT (S) T O OMEGA, PURCHASER MUST OBT AIN AN AUT HORIZED RET URN (AR) NUMBER FROM OMEGA’S CUST OMER SERVICE DEPART MENT (IN ORDER T O AVOID PROCESSING DELAYS). T he assigned AR number should then be marked on the outside of the return package and on any correspondence.The purchaser is responsible for shipping charges, freight, insurance and proper packaging to prevent breakage in transit. FOR WARRANTY RETURNS, please have the following informa-tion available BEFORE contacting OMEGA:1.Purchase Order number under which the product was PURCHASED,2.Model and serial number of the product under warranty, and3.Repair instructions and/or specific problems relative to the product.FORNON-WARRANTY REPAIRS,consult OMEGA for cur-rent repair charges. Have the following information avail-able BEFORE contacting OMEGA:1. Purchase Order number to cover the COST of the repair,2.Model and serial number of the product, and3.Repair instructions and/or specific problems relative to the product.OMEGA’s policy is to make running changes, not model changes, whenever an improvement is possible. This affords our customers the latest in technology and engineering.OMEGA is a registered trademark of OMEGA ENGINEERING, INC.© Copyright 2005 OMEGA ENGINEERING, INC. All rights reserved. T his document may not be copied, photocopied, reproduced, translated, or reduced to any electronic medium or machine-readable form, in whole or in part, without the prior written consent of OMEGA ENGINEERING, INC.Servicing North America:U.S.A.:One Omega Drive, Box 4047ISO 9001 Certified Stamford, CT 06907-0047Tel: (203) 359-1660FAX: (203) 359-7700e-mail:**************Canada:976 BergarLaval (Quebec) H7L 5A1, Canada Tel: (514) 856-6928FAX: (514) 856-6886e-mail:*************For immediate technical or application assistance:U.S.A. andSales Service: 1-800-826-6342 / 1-800-TC-OMEGA Canada:Customer Service: 1-800-622-2378 / 1-800-622-BEST Engineering Service: 1-800-872-9436 / 1-800-USA-WHEN TELEX: 996404 EASYLINK: 62968934 CABLE: OMEGA Mexico:En Espan ˜ol: (001) 203-359-7803e-mail:*****************FAX: (001) 203-359-7807**************.mxServicing Europe:Benelux:Postbus 8034, 1180 LA Amstelveen, The Netherlands Tel: +31 (0)20 3472121FAX: +31 (0)20 6434643Toll Free in Benelux: 0800 0993344e-mail:*****************Czech Frystatska 184, 733 01 Karviná, Czech Republic Republic:Tel: +420 (0)59 6311899FAX: +420 (0)59 6311114Toll Free: 0800-1-66342e-mail:*****************France:11, rue Jacques Cartier, 78280 Guyancourt, France Tel: +33 (0)1 61 37 2900FAX: +33 (0)1 30 57 5427Toll Free in France: 0800 466 342e-mail:**************Germany/Daimlerstrasse 26, D-75392 Deckenpfronn, Germany Austria:Tel: +49 (0)7056 9398-0FAX: +49 (0)7056 9398-29TollFreeinGermany************e-mail:*************United One Omega Drive, River Bend Technology Centre Kingdom:Northbank, Irlam, ManchesterISO 9002 Certified M44 5BD United KingdomTel: +44 (0)161 777 6611FAX: +44 (0)161 777 6622Toll Free in United Kingdom: 0800-488-488e-mail:**************.ukM1249/0205。
e-mail:**************For latest product manuals:FTH SERIESIndustrial Flow Through HeatersShop online atUser’s GuideDocument: 400-00003 Revision 0: 3-23-2009FTH SERIES HEATERS INSTALLATION, OPERATION AND MAINTENANCEOmega® flow through heaters are designed primarily for providing heat that regulates liquid temperature from 90°F to 190°F. The heaters have a titanium element that resists corrosion. The 304 Stainless Steel flow through tube is 15 inches long and has 1-½ inch NPT female pipe connections. Each heater has a 6 ft SJTW 12/3 or a 6 ft SJTW 14/3 power cord. The 115 V units have a 15P plug and the 240 V units have pig tales. The safety high limit trip point for the heater is 210°F. The 7.9” x 5.7” x 3.5” enclosure is made of ABS plastic and is water resistant.WARNING:Not for use as a Spa or Hot Tub heaterWARNING:Read all instructions before installation and operation.WARNING:Heater will fail if energized without proper fluid flow – 15 GPM minimum. WARNING:Pump must be running and fluid flowing before turning on power to the Heater. WARNING:Heater must be powered down for one to five minutes before turning off the pump and stopping fluid flowWARNING:Bleed the system of any air before applying power to the heater.WARNING:Heater failures due to insufficient flow or due to dry firing the heater are not covered under warranty.WARNING:Heater should always be mounted so that the water outlet is elevated a minimum of 3 inches above the water inlet. (See Figure A)WARNING:When using piping smaller than 1-1/2 inch, the heater is to be mounted in a vertical orientation. Fluid flow is to enter at the bottom and exit out the top. (SeeFigure B)WARNING:Minimum connecting pipe diameter is ¾ inch.WARNING:Piping connections are to meet all local plumbing codes.WARNING:Electrical connections must be performed in accordance with Articles 250 and 680 of the National Electric Code and by a qualified electrician.Water Out3” Min.Figure A – Mounting Method for 1-½ Inch PipeWater InWater OutFigure B – Mounting Method for Piping less than 1-½ InchDocument: 400-00003Revision 0: 3-23-2009 Model Number Series Wattage Voltage Phase AMP DrawFTH-1500-120FTH 1500 120 1 Ø 12.5FTH-2000-240FTH 2000 240 1 Ø 8.3FTH-3000-240FTH 3000 240 1 Ø 12.5FTH-4000-240FTH 4000 240 1 Ø 16.7FTH-5000-240FTH 5000 240 1 Ø 20.8FTH-6000-240FTH 6000 240 1 Ø 25.0Chart A – Electrical SpecificationsUNPACKING AND INSPECTION UPON RECEIPTThe FTH series heaters are shipped fully assembled and ready for installation. Check for any damage sustained during shipment and report damage to seller.INSTALLATIONPrior to installation remove any packing material from inside the heater. The FTH series heaters have 1-1/2 NPT female pipe threads. The equivalent male fittings are required to plumb the heater for installation. Seal both pipe joints with an approved sealant. Although the heater assembly is equipped with a water resistant enclosure, it is not intended for direct exposure to weather or immersion in water.TROUBLESHOOTING/PRECAUTIONSMinimum guidelines for properly installed heater to achieve effective operation:1)Proper Flow Rate: 15GPM minimum.2)Thermostats are designed for heater control only and are not to be used for control of motors orother components. Heater should be turned on/off at the supply breaker or switch, not the thermostat, when heater is being serviced.3)Heater should be plumbed below the lowest operating liquid level of the piping system.4)If the heater experiences a high temperature condition, the high limit thermostat will shut down theheater. Disconnect power to the heater and check for inadequate flow (clogged filter or line), or for possible air that may have accumulated in the system. Correct the problem, start the fluid flowing,and then reconnect power to the heater.5)To reset the heater controls, disconnect power to the heater and allow the fluid temperature tocool to 90°F. Then reconnect power to the heater.6)The power supply to the heater must be disconnected before draining the piping system and donot reconnect power until the piping system is refilled and the fluid is flowing.7)The power applied to the heater must be single phase. The heater must be protected by a circuitbreaker or fused disconnect switch rated for the appropriate Amp draw. (See Chart A) A ground fault circuit must be incorporated into the system.REPLACEMENT PARTSFor heaters that are beyond factory warranty, replacement High Limit and Control Thermostats can be acquired through electrical distributors. For heaters that are covered under warranty the heater assembly must be sent back to the seller for disposition. All returned heaters are subject to the terms and conditions of the warranty.Document: 400-00003Revision 0: 3-23-2009 DIMENSION AND WIRING DIAGRAMS 120V UNITS:15”2.3”2.3”15”It is the policy of OMEGA Engineering, Inc. to comply with all worldwide safety and EMC/EMI regulations that apply. OMEGA is constantly pursuing certification of its products to the European New Approach Directives. OMEGA will add the CE mark to every appropriate device upon certification.The information contained in this document is believed to be correct, but OMEGA accepts no liability for any errors it contains, and reserves the right to alter specifications without notice.WARNING: These products are not designed for use in, and should not be used for, human applications.WARRANTY/DISCLAIMEROMEGA ENGINEERING, INC. warrants this unit to be free of defects in materials and workmanship for a period of 13 months from date of purchase. OMEGA’s WARRANTY adds an additional one (1) month grace period to the normal one (1) year product warranty to cover handling and shipping time. This ensures that OMEGA’s customers receive maximum coverage on each product.If the unit malfunctions, it must be returned to the factory for evaluation. OMEGA’s Customer Service Department will issue an Authorized Return (AR) number immediately upon phone or written request.Upon examination by OMEGA, if the unit is found to be defective, it will be repaired or replaced at no charge. OMEGA’s WARRANTY does not apply to defects resulting from any action of the purchaser,including but not limited to mishandling, improper interfacing, operation outside of design limits, improper repair, or unauthorized modification. T his WARRANT Y is VOID if the unit shows evidence of having been tampered with or shows evidence of having been damaged as a result of excessive corrosion;or current, heat, moisture or vibration; improper specification; misapplication; misuse or other operating conditions outside of OMEGA’s control. Components in which wear is not warranted, include but are not limited to contact points, fuses, and triacs.OMEGA is pleased to offer suggestions on the use of its various products. However, OMEGA neither assumes responsibility for any omissions or errors nor assumes liability for any damages that result from the use of its products in accordance with information provided by OMEGA, either verbal or written. OMEGA warrants only that the parts manufactured by the company will be as specified and free of defects. OMEGA MAKES NO OTHER WARRANTIES OR REPRESENTATIONS OF ANY KIND W HATSOEVER, EXPRESSED OR IMPLIED, EXCEPT THAT OF TITLE, AND ALL IMPLIED WARRANTIES INCLUDING ANY WARRANTY OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE HEREBY DISCLAIMED. LIMITATION OF LIABILITY: The remedies of purchaser set forth herein are exclusive, and the total liability of OMEGA with respect to this order, whether based on contract, warranty, negligence, indemnification, strict liability or otherwise, shall not exceed the purchase price of the component upon which liability is based. In no event shall OMEGA be liable for consequential, incidental or special damages.CONDITIONS: Equipment sold by OMEGA is not intended to be used, nor shall it be used: (1) as a “Basic Component” under 10 CFR 21 (NRC), used in or with any nuclear installation or activity; or (2) in medical applications or used on humans. Should any Product(s) be used in or with any nuclear installation or activity, medical application, used on humans, or misused in any way, OMEGA assumes no responsibility as set forth in our basic WARRANTY /DISCLAIMER language, and, additionally, purchaser will indemnify OMEGA and hold OMEGA harmless from any liability or damage whatsoever arising out of the use of the Product(s) in such a manner.RETURN REQUESTS/INQUIRIESDirect all warranty and repair requests/inquiries to the OMEGA Customer Service Department. BEFORE RET URNING ANY PRODUCT (S) T O OMEGA, PURCHASER MUST OBTAIN AN AUT HORIZED RET URN (AR) NUMBER FROM OMEGA’S CUST OMER SERVICE DEPART MENT (IN ORDER T O AVOID PROCESSING DELAYS). The assigned AR number should then be marked on the outside of the return package and on any correspondence.The purchaser is responsible for shipping charges, freight, insurance and proper packaging to prevent breakage in transit.FOR WARRANTY RETURNS, please have thefollowing information available BEFOREcontacting OMEGA:1.Purchase Order number under which the productwas PURCHASED,2.Model and serial number of the product underwarranty, and3.Repair instructions and/or specific problemsrelative to the product.FOR NON-WARRANTY REPAIRS,consult OMEGA for current repair charges. Have the following information available BEFORE contacting OMEGA:1. Purchase Order number to cover the COST of the repair,2.Model and serial number of the product, and 3.Repair instructions and/or specific problems relative to the product.OMEGA’s policy is to make running changes, not model changes, whenever an improvement is possible. This affords our customers the latest in technology and engineering.OMEGA is a registered trademark of OMEGA ENGINEERING, INC.© Copyright 2009 OMEGA ENGINEERING, INC. All rights reserved. T his document may not be copied, photocopied,reproduced, translated, or reduced to any electronic medium or machine-readable form, in whole or in part, without theprior written consent of OMEGA ENGINEERING, INC.Where Do I Find Everything I Need for Process Measurement and Control?OMEGA…Of Course!Shop online at SMTEMPERATUREⅪߜThermocouple, RTD & Thermistor Probes, Connectors, Panels & AssembliesⅪߜWire: Thermocouple, RTD & ThermistorⅪߜCalibrators & Ice Point ReferencesⅪߜRecorders, Controllers & Process MonitorsⅪߜInfrared PyrometersPRESSURE, STRAIN AND FORCEⅪߜTransducers & Strain GagesⅪߜLoad Cells & Pressure GagesⅪߜDisplacement TransducersⅪߜInstrumentation & AccessoriesFLOW/LEVELⅪߜRotameters, Gas Mass Flowmeters & Flow ComputersⅪߜAir Velocity IndicatorsⅪߜTurbine/Paddlewheel SystemsⅪߜTotalizers & Batch ControllerspH/CONDUCTIVITYⅪߜpH Electrodes, Testers & AccessoriesⅪߜBenchtop/Laboratory MetersⅪߜControllers, Calibrators, Simulators & PumpsⅪߜIndustrial pH & Conductivity EquipmentDATA ACQUISITIONⅪߜData Acquisition & Engineering SoftwareⅪߜCommunications-Based Acquisition SystemsⅪߜPlug-in Cards for Apple, IBM & CompatiblesⅪߜData Logging SystemsⅪߜRecorders, Printers & PlottersHEATERSⅪߜHeating CableⅪߜCartridge & Strip HeatersⅪߜImmersion & Band HeatersⅪߜFlexible HeatersⅪߜLaboratory HeatersENVIRONMENTALMONITORING AND CONTROLⅪߜMetering & Control InstrumentationⅪߜRefractometersⅪߜPumps & TubingⅪߜAir, Soil & Water MonitorsⅪߜIndustrial Water & Wastewater TreatmentⅪߜpH, Conductivity & Dissolved Oxygen InstrumentsM4786/0409。
ASHRAE Handbook 2010 Refrigeration 中文目录2009版的基础知识部分让人叹为观止，2010版的制冷部分只能用无言以对。
真郁闷，昨天被人拉到公司打酱油，所以只能先翻到二级标题。
以后有时间慢慢把三级标题翻出来。
光目录就弄出几十页的动静，何以堪啊。
2 2010 Refrigeration 46Dedication 46编著人员 46技术委员会、工作组、和技术资源组 46ASHRAE 研究：提高生活品质 46序 46系统和方法（Systems and Practices） 462.1.1 卤代烃制冷系统 462.1.2 氨制冷系统 472.1.3 二氧化碳制冷系统 472.1.4 过量充液系统（Liquid Overfeed Systems） 482.1.5 制冷系统的部件匹配（Component Balancing in Refrigeration Systems） 482.1.6 制冷剂系统的化学 482.1.7 制冷剂系统内水分和其它杂质的控制 482.1.8 设备和系统脱水、充注和试验 492.1.9 制冷剂的密封、恢复、回收和再利用 49部件和设备 492.1.10 制冷剂管路的绝热系统 492.1.11 制冷剂控制元件 502.1.12 制冷剂系统内的润滑油 502.1.13 制冷系统的载冷剂 512.1.14 受迫对流空气冷却器 512.1.15 零售食品存储冷冻和设备 512.1.16 食品服务和一般商业冷冻设备 522.1.17 家用冰箱和冷冻机 522.1.18 吸收设备 52食品冷却和储藏 522.1.19 食品的热力性质 522.1.20 食品的冷却和冷冻时间 532.1.21 日用品储藏设备 532.1.22 食品微生物和冷藏 532.1.23 冷藏设备设计 542.1.24 冷藏设备负荷 54冷冻运输 542.1.25 货运集装箱、轨道运输、拖车和卡车 542.1.26 海运冷冻 552.1.27 航空运输 55食品、饮料和花卉应用 552.1.28 水果、蔬菜和鲜花的预冷 552.1.29 工业食品冷冻系统 562.1.30 肉类产品 562.1.31 禽类产品 562.1.32 鱼类产品 572.1.33 乳类产品 572.1.34 蛋和蛋类产品 572.1.35 阔叶树和藤类水果 582.1.36 柑橘类水果、香蕉和亚热带水果 582.1.37 蔬菜 592.1.38 果汁浓缩物和冷藏果汁产品 592.1.39 饮料 592.1.40 已处理食品，预加工过的食品和精制食品 60 2.1.41 烘焙食品 602.1.42 巧克力、糖果、坚果、干果和干燥蔬菜 61 工业应用 612.1.43 制冰 612.1.44 溜冰场 612.1.45 混凝土坝和次表土 622.1.46 化工中的制冷 622.1.47 低温应用 622.1.48 超低温制冷 632.1.49 生物医学应用和低温制冷 632.1.50 制冷术语 632.1.51 规范和标准 63ASHRAE Handbook 2009 Fundamental 中文目录花了三天的业余时间才把《ASHRAE Handbook 2009 Fundamental》目录翻译成中文，因为涉及的学科太多，很多专业名称采用的是直译，后续如果在阅读过程中有新发现我会修改过来。
MeltFlipperTM融胶翻转技术图1 多腔模具的不平衡充模可以通过监控和调节模具内的压力和温度、采用特殊的熔体旋转工艺、针阀式浇口以及改进热流道设计等方法加以解决。
图中的瓶盖模具使用了赫斯基通过计算机辅助分析设计出的热流道分流板随着多腔模具的使用日益频繁，以及模腔数量的不断增加，充模不均已成为注塑加工商在生产过程中必须面对和予以解决的问题。
为此，热流道系统供应商及其他一些厂商均推出了各自的解决方案。
这些方案可能基于不同的技术，但它们的目的却是相同的，即实现注塑的均匀充模。
在多腔模具中，塑料熔体达到平衡流动的公认准则是，使熔体从注射点到每一个模腔都具有相同的流动距离。
但是，这种“自然平衡”的多腔模具容易出现非均匀充模的现象，从而导致有的模腔可加工出完好的制品，而有的模腔却只能得到带有缺料、飞边及过度充模等缺陷的制品。
这对于注塑加工商而言虽不是一个新问题，但有迹象表明，这一问题的解决，对于那些原本使用简单模具的注塑加工商而言显得非常重要，因为他们已开始使用更复杂的多腔模具。
然而，并非所有的被访者都同意上述观点。
热流道供应商D-M-E公司的发言人说：“我们看不出更多的充模不平衡问题，主要是因为我们避免了浇口尺寸的改变。
”D-M-E公司为预防制品出现潜在的缺陷，在一套几何形状均衡的模具上反复运用Moldflow软件进行了分析，他们得出的结论是：“即使运用了Moldflow分析软件，你所能做的也只是这些。
假如你改变了浇口位置，之后制品的熔接缝位置也有所变化，这可能是因为剪切力不平衡而导致的变化，因此你不得不改变浇口尺寸来予以补偿。
”然而，D-M-E公司建议，尽量不要进行这样的改动，因为改变浇口尺寸意味着模具加工窗口的缩小。
图2 Beaumont公司的MeltFlipper技术专用于解决模具不平衡的问题。
iMARC是其最新型号，可通过对模具分型线的简单调节来改变熔体的旋转程度大多数被访者都认为，多腔模具的不平衡充模确实已成为近年来的一个热议话题。
