轿车地毯专用胶乳

轿车地毯专用胶乳兰化公司研究院采用分解型引发剂、复合型乳化剂，由苯烯。丁二烯和多种功能单体通过乳液法共聚而研制成功了轿车地毯专用胶乳。该胶乳干燥速度快、流动性、粘接性、填充性都非常好。使用该胶乳制成的地毯具有良好的热塑性、形态稳定性。耐水性、耐清洗剂...     

墙面砖温度场与热应力场的分析

本文利用杜哈美尔(Duhamel)法,在(a)一般情况下;(b)上、下表面存在温差;(c)匀速加热或冷却这三种情况下,得到了辊道窑烧成墙面砖时,制品内部的温度场与热应力场的理论解。并分析了上、下表面温差对墙面砖烧成的影响,得到了匀速加热或冷却时,温度梯度、温度变化速率的发展趋势,以及制品最大温差、热应力与加热或冷却速度及制品厚度的关系式。     

基于ANSYS对HRHCM随形绝热结构热响应分析

采用ANSYS软件模拟分析模芯水热性快速热循环热响应过程,提出了一种带有随形绝热层和随形换热通道的组合式模芯换热结构,分析该特殊模具结构和绝热条件对加热冷却效率和模温均匀性的影响。结果表明,使用该结构,加热和冷却阶段所用时间分别缩短125.0%和136.8%;加热速率和冷却速率分别提高124.2%和135.8%;加热和冷却阶段最大温差分别降低9.0%和24.2%。     

玻璃熔窑冷却部温度控制技术

从冷却部传热方式的特点论述了冷却部玻璃液温度控制技术,深入研究了冷却部加热技术,并对加热装置提出自己独特的观点.     

导热油加热技术在压延机中的应用研究和传热计算分析

对压延机辊筒内的导热油加热和冷却方式、结构、系统进行了分析,并对压延机辊筒内的导热油加热和冷却计算方法进行了研究.     

DSC法鉴定高分子材料组成的研究

用DSC方法研究了“桑塔纳”轿车洗涤泵壳体的组成.对试样进行了熔体淬火、改变加热扫描速率和冷却速率、部分扫描、部分扫描→等温扫描→继续扫描等试验,考察这些试验对DSC曲线的影响,从而确定试样是由两种高聚物组成的共混物.经用Barta添加热分析法鉴别,证明了试样为聚酰胺-6和高密度聚乙烯的共混物.     

聚丙烯原液着色异形丝与喷汽卷曲试验机

聚丙烯纤维具有比重小、强力高、耐磨好、耐酸、耐碱等特性。因此,采用原液着色纺制聚丙烯异形丝制作丙纶地毯,不仅耐磨、轻盈、色泽鲜艳、弹性优良,而且价廉易制,作为飞机、轿车地毯尤为合适,随着     

硫与硫酸新技术

<正>2013024硫酸生产工艺本发明涉及具有工艺气体侧和传热介质侧的冷凝器,所述冷凝器用于输送包含可冷凝成分的加热工艺气体至冷凝侧的入口,以及从冷凝侧的出口回收冷却的工艺气体,并进一步用于在靠近冷凝器一端的位置回收冷凝水,所述冷凝器的工艺气体侧分为工艺气体冷却区和再加热区,其中冷却区具有冷却传热介质入口和加热传热介质出口,再加热区位于工艺气体冷却设备段的下方,用于工艺气体的再加热以及采用此冷凝器的硫酸冷凝和生产过程。[WO2012136307(A1)]     

最新专利

【发明名称】一种塑料模具快速加热及冷却的温度控制装置【申请号】200710016224【申请日】2007年7月26日【摘要】本发明提供了一种塑料模具快速加热及冷却的温度控制装置,包括加热装置、冷却装置、高温动力装置、低温动力装置、回路控制开关和控制单元,加热装置、高温动力装置     

陶瓷注射成型浇口加热—冷却装置的设计及作用

设计了－陶瓷注射成型浇口加热－冷却装置，其体积小，加工容量，操作方便、加热迅速，冷却快，解决了浇口过早封凝问题。对比实验结果表明，使用这种加热－冷却装置后，注射成型试件的密度增大，内部缺陷得以消除。     

Some considerations of heat-transfer problems in thermoforming

Details are given below of how the heat-up process for radiation methods may be expressed mathematically. In order to fulfill practical requirements, a process must ensure calculation of necessary heating time using process-specific characteristic curves with a minimum of mathematical effort. To this end the amount of heat actually absorbed by the surface of the O product must be known when sheets are heated by radiation. This can easily be determined through measurement of sheet surface temperature. It will be shown that if certain preconditions are satisfied, then variations in the distance of the IR-heaters have no effect on the temperature profile of the sheet. With poly(methyl methacrylate) (PMMA) the nature of coloration does not play a significant role. Investigations into the cooling process centered on a number of cooling methods and tool materials. The dynamic behavior of tempered and untempered thermoforming tools showed similarities to work already carried out in the injection molding sector. Consideration was given to possible ways of using the “Thermolog” analog computer, developed at IKV, to calculate the necessary cooling times in the production of thermoformed parts. Input values and basic data on temperature-time curves, necessary for the compilation of cooling curves using the analog simulator, were derived from appropriate tests on a thermoforming machine.     

Coupled thermo‐mechanical analysis for plastic thermoforming

An FEM software ARVIP‐3D was developed to simulate the process of 3‐D plastic thermoforming. The coupled thermo‐mechanical analysis, thermal stress and warpage analysis for plastic thermoforming was carried out by means of this software. Rigid visco‐plastic formula was adopted to simulate the deforming process. During this process, the method of comparing velocity, time and area was adopted as the contact algorithm at different nodes and triangular elements. Sticking contact was assumed when the nodes become in contact with tool surface. The Arrhenius equation and the Williams equation were employed to ascertain the temperature dependence of material properties. In order to analyze the temperature field of plastic thermoforming, the Galerkin FEM code and the dynamic heat conduction boundary condition were adopted; latent heat and deformation heat were treated as dynamic internal heat sources. Based on the above, the model of coupled thermomechanical analysis was established. Assuming that the thermal deformation occurs under elastic conditions, the thermal stress and the warpage following the cooling stage were estimated. Experiments of plastic thermoforming were made for high‐density polyethylene (HDPE). An infrared thermometer was used to record the temperature field and a spiral micrometer was used to measure the thickness of the part. Results of numerical calculation for thickness distribution, temperature field and warpage were in good agreement with experimental results.     

Wall thickness distribution in thermoformed food containers produced by a Benco aseptic packaging machine

Effects of process parameters such as forming temperature, forming air pressure and heating time on wall thickness distribution in plug‐assist thermoformed food containers using multilayered material were investigated. Multilayered rollstockbase material formed into containers by thermoforming process using a Benco aseptic packaging machine. Forming temperatures in the range of 131–170°C, airforming pressures of 2, 3, 3. 5 and 4 bars, and heating times of 66, 74, 84, 97 and 114 seconds were used in the thermoforming process. Analysis of wall thickness data obtained for the thermoforming parameters used in this study showed that wall thickness was significantly affected by forming temperature, pressure and heating time at 0.05 significance level. Besides the processing parameters, wall location, container side, and their interactions significantly affected wall thickness. Forming temperature was found to be the principle parameter influencing wall thickness distribution in a plug‐assist thermoforming operation. The optimum operating conditions of the packaging machine for the thermoforming process are: 146–156°C for forming temperature, 2–4 bars for air‐forming pressure and 74–97 seconds for heating time.     

Improved mathematical modeling for the sheet reheat phase during thermoforming

In any thermoforming process, plastic sheet heating is the most important phase as it is responsible for final part quality as well as overall process efficiency and productivity. The goal of the study reported here was to improve existing mathematical models to accurately predict the temperature profile inside a heated sheet, where the model could be used to better control the overall thermoforming process. A mathematical model with temperature dependent, variable sheet material properties including density, thermal diffusivity, specific heat, and thermal conductivity was developed and validated against experimental data. Models with constant and variable plastic sheet properties were created, simulated, and compared in Matlab. The models were validated by experiments which obtained temperature profiles at different depths within a plastic sheet by inserting thermocouples and recording temperatures. Further, the effect of sheet color on heating was investigated by considering two extreme cases: white (transparent) and black (opaque) colored sheets, and the effect of oven air temperature and velocity on sheet heating was also investigated. Results indicated that a variable properties model was needed to control sheet reheating especially with narrow forming windows, and that the heating profiles required for colored and noncolored sheets were very different. POLYM. ENG. SCI., 2012. © 2011 Society of Plastics Engineers     

低熔点熔盐蓄热罐内温度分布与散热损失实验

为了研究熔盐蓄热罐内的温度分布变化与散热规律,采用课题组搭建的槽式聚光熔盐集热、传热与蓄热实验台中的熔盐罐作为实验装置,通过加热、内循环及冷却等实验,得到了罐体在各运行状态下的温度分布数据,并分析拟合得到了自然冷却降温阶段熔盐罐散热功率随时间和温度的变化曲线。实验结果表明：加热时,加热器下部熔融盐出现明显的温度分层现象。混合均匀后的冷却降温过程,熔融盐基本不出现温度分层现象。     

Role of additives in influencing heating and melting of polymers during thermoforming

The heating stage in thermoforming of amorphous and semi-crystalline polymers was analyzed for constant heat flux conditions using an energy balance model; candidate polymers were high impact polystyrene and isotactic polypropylene. Using an analytical solution, temperature differences as large as 100°C were predicted to arise between the surface and the interior of the sheet being thermoformed for conditions chosen in this work, and these can limit the heat flux being used. A Matlab program was used to compute temperature and crystallinity profiles for crystal melting. Melting took almost as much time as required to heat the surface of the film to the crystal melting point. High thermal conductivity additives, such as calcium carbonate and graphene, can provide temperature uniformity, and the additive uniformity can be verified using thermogravimetric analysis. The ability of these additives to provide temperature uniformity and to reduce energy consumption and heating time is determined in a quantitative manner. Both additives improve heat transfer, and, at the same added volume fraction, graphene is more effective. However, calcium carbonate has a lower cost. The role of density, specific heat, thermal conductivity, and amount of the polymers and additives in influencing temperature and crystallinity profiles was explored, and methods of carrying out thermoforming in an energy efficient manner are proposed.     

热成型过程中的冷却过程分析

建立了热成型冷却过程分析所用的物理模型和数学模型，并给出了速算图。     

Development of rapid heating and cooling systems for injection molding applications

The injection molding process has several inherent problems associated with the constant temperature mold. A basic solution is the rapid thermal response molding process that facilitates rapid temperature change at the mold surface thereby improving quality of molded parts without increasing cycle time. Rapid heating and cooling systems consisting of one metallic heating layer and one oxide insulation layer were investigated in this paper. Design issues towards developing a mold capable of raising temperature from 25°C to 250°C in 2 seconds and cooling to 50°C within 10 seconds were discussed. To reduce thermal stresses in the layers during heating and cooling, materials with closely matched low thermal expansion coefficient were used for both layers. Effects of various design parameters, such as layer thickness, power density and material properties, on the performance of the insert were studied in detail with the aid of heat transfer simulation and thermal stress simulation. Several rapid thermal response mold inserts were constructed on the basis of the simulation results. The experimental heating and cooling response agrees with the simulation and also satisfies the target heating and cooling requirement.     

A method for the rapid processing of thermoplastic articles

A new method for increasing the productivity of molded polymeric articles and a new kind of molding material are described. This process eliminates the heating and cooling time associated with the conventional injection molding process. Polymeric granules with heterogeneous dielectric loss characteristics are used so that during dielectric heating the surfaces of the granules melt and fuse. During cooling, the heat flows from the shell of each granule to the core, rendering the article rigid almost immediately. An analysis is done which shows that this process is feasible. Based on the analytical results, the material requirements are specified. Experimental results confirm the theoretical predictions and the viability of the basic concept. Heating and cooling are accomplished in a time period of the order of 1 sec.     

冰箱内胆真空成型模具设计方法

针对冰箱内胆体积大、壁薄、形状复杂的特点，根据塑料模具设计程序，围绕冰箱内胆真空成型工艺特点，介绍冰箱内胆真空成型模具设计所涉及的内容及设计方法，包括制品结构分析、设计资料的准备、成型体设计、抽芯机构设计、抽气孔设计、加热和冷却系统设计、密封结构设计和切边装置设计等。