1、2003 中国聚氨酯行业整体淘汰 ODS 国际论坛论文集360我国聚氨酯无氟高压发泡模塑生产成套设备曾红 邱红历(中国轻工业机械总公司武汉轻工业机械厂 湖北武汉 430034) 摘 要：介绍了目前我国采用环戊烷和二氧化碳作发泡剂替代 CFC-11 的聚氨酯泡沫发泡新工艺路线，以及对应于这两种新工艺路线，武汉轻工业机械厂所开发研制出的两大类成套设备的用途及构成要点。关键词：发泡设备；聚氨酯泡沫塑料；模塑；无氟；预混为了加快履行联合国关于消耗臭氧层物质的蒙特利尔协定书的义务，根据我国编制并修订的中国消耗臭氧层物质逐步淘汰国家方案的精神，聚氨酯泡沫行业 2010 年前要实现 CFC-11 零消费。据
2、此，我们采用对大气臭氧层无任何损害的环戊烷和二氧化碳作为聚氨酯硬泡和软泡的发泡剂，以替代CFC-11，且按新的工艺路线，经消化吸收并改进创新世界上先进的技术，研制了分别使用两种新发泡剂的聚氨酯无氟高压发泡模塑生产成套设备。1 聚氨酯无氟(环戊烷)高压发泡模塑生产成套设备环戊烷的物理性质及与 CFC-11 的比较如表 11。表 1 环戊烷的物理性质及与 CFC-11 的比较发泡剂 分子式 相对分子质量 密度g/cm3 沸点 气相热导率 mW/(mK) 蒸汽压 kPa 爆炸极限 (v/v)% 臭氧消耗潜值(ODP 值)环戊烷 C5H10 70 0.74 49 12.0 34 1.48.0 0CFC
3、-11 CCl3F 137.4 1.49 24 8.5 无 1.0注：密度为 20数据，气相热导率为 25数据，蒸汽压为 20数据。根据环戊烷的物理性质，使用环戊烷作聚氨酯硬泡发泡剂的优点为：对大气臭氧层无破坏作用，环保性能较好；价廉，资源丰富；室温下为液态；因分子量低，同密度的泡沫所需发泡剂用量比 CFC-11小。缺点是：易燃、易爆，设备费用高；气相热导率较 CFC-11 高，因而泡沫绝热性相对差些。目前国内海尔、科龙、新飞、长岭等厂家已大批使用环戊烷作冰箱、冷柜绝热层硬泡的发泡剂。 使用环戊烷作发泡剂的生产工艺路线如下： 2根据环戊烷特性和工艺路线，我们研制了聚氨酯无氟（环戊烷）高压发泡模
4、塑生产成套设备。在设备研制时特别注重防爆安全措施的研发，确保安全生产。聚氨酯无氟（环戊烷）高压发泡模塑生产成套设备由环戊烷/多元醇预混系统、聚氨酯无氟（环戊烷）高压发泡机和聚氨酯无氟发泡模塑生产线组成。各组成部分的构成描述如下：2003 中国聚氨酯行业整体淘汰 ODS 国际论坛论文集3611.1 环戊烷/多元醇预混系统 2 根据环戊烷的特性，新开发的环戊烷/多元醇预混系统的环戊烷贮料罐，须防止外力的撞击，周围应无火花，如果地面条件不能满足安全要求，或外界气温可能低于 0，则贮料罐宜置于地下。环戊烷/多元醇预混系统见图 1。图 1 环戊烷预混系统工艺流程图环戊烷和多元醇分别采用二套高精度、中低压
5、的计量泵计量，以保证混合配比的精度。采用混合能力高、低热量产生、防静电的静态混合器，对环戊烷与多元醇进行混合，使环戊烷均匀地溶入多元醇，提高泡沫质量。形成的混合料贮存于由氮气保压的多元醇/ 环戊烷料罐，以供发泡机使用。环戊烷/多元醇预混系统的安全配置为：环戊烷的计量泵防爆；所有可能接触环戊烷及其气体的装置防静电火花；电机、电器元件均选用防爆等级；且相应管道、接头及阀双层密封，管道上配置电控截止阀；装有环戊烷及其混合料的容器均输入氮气保压，料罐搅拌电机与搅拌轴的连接采用磁性连轴节；在环戊烷贮料罐、计量、混合及混合料罐等区域均配置隔板或护罩，并设有检测探头、抽风系统及防爆控制系统。该防爆控制系统的
6、电源与设备电源分开，并分三级进行防爆控制：第一级为正常工作时控制风机低速抽风，换气量约为每小时换气 10 次； 2第二级为当检测传感器检测到环戊烷浓度达到爆炸下限的20%时， 2控制风机高速抽风；第三级为当检测传感器检测到环戊烷浓度达到爆炸下限的 40%时， 2则切断设备电源，关闭环戊烷进料阀，并使风机高速抽风，使环戊烷的释放浓度被控制在安全值以下。1.2 聚氨酯无氟(环戊烷)高压发泡机 环戊烷/多元醇混合料的料罐由氮气保压，其搅拌轴与搅拌电机的连接采用磁性连轴节，电机为防爆电机，且料罐用隔离罩分隔，并配有检测探头、抽风系统及防爆三级控制系统；混合料计量泵电机为防爆电机，计量泵及电机也用隔离罩
7、分隔，并配有检测探头、抽风系统及防爆三级控制系统；异氰酸酯料罐和计量泵不必防爆；根据环戊烷释放速度和释放量，可选用可充氮气的混合头，使注射前可向模腔充氮，且注射时使混合料与异氰酸酯进行高速碰撞混合。所有接触混合料的装置须防静电火花并接地。聚氨酯无氟（环戊烷）高压发泡机示意图见图 2。2003 中国聚氨酯行业整体淘汰 ODS 国际论坛论文集362图 2 聚氨酯环戊烷高压发泡机简图1.3 聚氨酯无氟(环戊烷)发泡模塑生产线该聚氨酯无氟（环戊烷）发泡模塑生产线按形式可分为直线式、水平环行式和垂直环行式。各种形式生产线均根据原料加工工艺情况、运行速度及产量决定生产线工位数。a. 直线式聚氨酯无氟（环戊
8、烷）发泡模塑生产线直线式聚氨酯无氟（环戊烷）发泡模塑生产线示意图见图 3。图 3 直线式聚氨酯环戊烷发泡模塑生产线简图该生产线用于冰箱箱体隔热层的发泡生产。采用固定模架结构，模具与模架设计为一体；混合头和冰箱分别由小车带动，在模架、烘箱和下线升降台之间自动识别运动。生产线全自动完成冰箱体的预热、上模架、浇注、固化及下线等任务。浇注、固化区的安全要求为：模板、模芯由水加热或热风加热；模架上所有可能接触释放出的环戊烷的电机、电器元件均须选用防爆等级或选用增安型加浇注后停电来防爆。停电时间依发泡时环戊烷气体的释放曲线（见图 4）可选为 1 min；机械运动件均须防静电火花，机械构件均接地；将模架区进
9、行隔离，并设置检测探头、抽风系统及防爆三级控制系统。b. 水平环行式聚氨酯无氟（环戊烷）发泡模塑生产线 该生产线色彩小游戏用于冰箱箱体隔热层的发泡生产。采用模架小车装载模具；链传动使载模小车作水平环状间歇移动；除操作工位（上、下箱体、清理、开、闭、锁模、浇注及抽风）外，其余工位均被罩在半环行固化烘箱内，烘箱采用热风循环加、保温。2003 中国聚氨酯行业整体淘汰 ODS 国际论坛论文集363浇注、固化区的安全要求为：所有电机、电器元件均采用防爆等级；机械运动件均须防静电火花，机械构件均接地；烘箱上热风循环风机及其电机须防爆；根据环戊烷在发泡时的释放曲线（见图 4） ，在浇注工位及浇注后 1 mi
10、n 内模具运行区间的上、下方区域，设置抽风装置，并在烘箱内及浇注处设置检测探头及防爆三级控制系统。水平环行式聚氨酯无氟(环戊烷 )发泡模塑生产线示意图见图 5。图 4 冰箱腔发泡时环戊烷气体释放图图 5 水平环行式聚氨酯无氟 (环戊烷)发泡模塑生产线简图c. 垂直环行式聚氨酯无氟（环戊烷）发泡模塑生产线（见图 6） 。该生产线用于冰箱箱门隔热层的发泡生产。采用模架小车装载模具；链传动使载模小车作垂直环状间歇移动；除操作工位（上、下箱门、清理、开、闭、锁模、浇注及抽风）外，其余工位均被罩在矩形固化烘箱内，烘箱采用热风循环加、保温；开、合模采用气、液压控制机械手。浇注、固化区的安全要求同上述水平环
11、行式无氟发泡模塑生产线。垂直环行式聚氨酯无氟（环戊烷）发泡模塑生产线示意图见图 6。2003 中国聚氨酯行业整体淘汰 ODS 国际论坛论文集364图 6 垂直环行式聚氨酯无氟发泡模塑生产线简图2 聚氨酯无氟(二氧化碳)高压发泡模塑生产成套设备二氧化碳的主要物理性质见表 21,3。表 2 二氧化碳的主要物理性质发泡剂分子式气相热导率(25)mW/(mK)临界温度/临界压力/MPa ODP 值二氧化碳 CO2 16.3 31 7.36 0温度及压力对二氧化碳密度的影响见图 73。110，220，330，440，550，660图 7 CO2 密度随温度压力变化图二氧化碳作发泡剂的优点为：二氧化碳价廉
12、，降低发泡成本；改善混合质量，减少成型重量，改善泡沫特性；二氧化碳不可燃、环保，有丰富的自然资源。该发泡剂在国内正开始使用。使用二氧化碳作发泡剂的加工方法有“批量”和“在线”两种，则工艺路线相应有以下两条 3。2.1 “批量”加工方法的工艺路线“批量”加工方法的工艺路线如下：2003 中国聚氨酯行业整体淘汰 ODS 国际论坛论文集365“批量”加工方式各批次二氧化碳与多元醇或异氰酸酯的溶解比可不同。2.2 “在线”加工方法的工艺路线“在线”加工方法的工艺路线框图如下：“在线”加工方法允许每次浇注时二氧化碳的量可以不同，该方法适于连续生产。由表 2 及图 7 可知，液态二氧化碳只存在于 31以下
13、、压力 7.36 MPa 以上，且温度及压力对二氧化碳的密度影响很大，所以研制的设备充分考虑温度与压力对二氧化碳计量精度的影响。根据以上所述特征，我们研发了聚氨酯无氟（二氧化碳）高压发泡模塑生产成套设备。由于“在线”加工方法适于连续生产，以下主要介绍与“批量”加工方法工艺路线相适应的聚氨酯无氟（二氧化碳）高压发泡模塑生产成套设备。聚氨酯无氟（二氧化碳）高压发泡模塑生产成套设备由二氧化碳预混系统、聚氨酯无氟（二氧化碳）高压发泡机、聚氨酯无氟（二氧化碳）发泡模塑生产线组成。各组成部分的构成如下：（1） 二氧化碳预混系统 3 某一组分经高精度、中低压的计量泵计量进入静态混合器， 4747 小游戏并进
14、入预混料罐循环；同时，气态二氧化碳经恒质量流量的计量单元被注入组分中。由于采用恒质量流量，所以二氧化碳的计量精度高，与温度、压力的变化无关。二氧化碳注入时间取决于预混料罐的容积、二氧化碳与组分的溶解比及二氧化碳的质量流量。静态混合器能使二氧化碳均匀地溶解在组分中，而不是粗略地混合。这不仅节约二氧化碳的耗量，还防止泡沫产生洞穴，改善模塑质量。当二氧化碳按设定比例均匀地溶解于组分原料中后，预混料罐加料阀被控制打开，将混合完毕的二氧化碳/ 组分的混合料送入无氟（二氧化碳）高压发泡机的料罐。二氧化碳预混系统示意图见图 8。 2003 中国聚氨酯行业整体淘汰 ODS 国际论坛论文集366图 8 二氧化碳
15、预混系统工艺流程图（2） 聚氨酯无氟（二氧化碳）高压发泡机构成与有氟高压发泡机相似（略） 。（3） 聚氨酯无氟（二氧化碳）发泡模塑生产线该聚氨酯无氟（二氧化碳）发泡模塑生产线按形式可分为转台式和水平环行式。转台式聚氨酯无氟（二氧化碳）发泡模塑生产线(见图 9)和水平环行式聚氨酯无氟（二氧化碳）发泡模塑生产线（见图 10）均根据原料加工工艺情况、运行速度及产量决定生产线工位数。两种形式生产线均可用于聚氨酯高回弹汽车坐垫、靠垫及头枕、摩托车坐垫等的冷熟化发泡生产。转台式需要的动力配置小，节约能源；管道固定安装，不易损坏；运行成本低；适于大批量同品种生产。水平环行式方便换模具，适于小批量多品种生产。
16、 图 9 转台式聚氨酯无氟(二氧化碳)发泡模塑生产线转台、水平环形式发泡生产线均由电机驱动，按工艺需要间歇或连续运转，其上配备水、电、气、液源，安装在转台和输送车上的模架可自动进行气、液自控的开、合、锁模的动作，根据工艺需要配备单、双、多混合头，并配置机械手带动混合头进行自动识别模具的浇注。3 结束语以上两大类成套设备均采用计算机技术控制，如：网络技术、逻辑控制技术等。采用人机界面进行2003 中国聚氨酯行业整体淘汰 ODS 国际论坛论文集367数据的输入和监控，并根据用户需要可配制远程监控装置。还应用了最新的变频计量、传动及伺服技术。对温度、压力、气体浓度、速度、位置、工位识别、安全保护等均
17、采用了多种传感技术来检测，使设备的性能和使用效果得到提高，成为具有国际先进水平的机电一体化产品。图 10 水平环行式聚氨酯无氟(二氧化碳)发泡模塑生产线聚氨酯无氟（环戊烷）高压发泡模塑生产成套设备和聚氨酯无氟（二氧化碳）高压发泡模塑生产成套设备先后有多套或部分在海尔、新飞、科龙和澳柯玛等厂家投入使用，且性能稳定、可靠，得到了用户的好评，其技术水平达到世界先进水平。随着世界科学技术的不断发展，将研制出更新、更好、更安全、更经济且环保的发泡剂及生产工艺，我们也将开发出更完美的生产设备，为人类创造财富、保护生存环境而作出更大的贡献！参考文献1 国家环保总局对外经济合作领导小组办公室、 联合国工业发展
18、组织、北京华塑贸易公司. 聚氨酯硬泡 CFC-11 替代技术手册. 2002 年 8 月. 352 Elastogran GmbH. Processing of Cyclo-pentane in the Refrigerator Industry3 Elastogran GmbH. CO2-loading of PUR-systems; Processing Alternatives (On-Line and Batch-Process). 1997 The Complete RIM Equipments for PU High Pressure CFC-free Foaming Proces
19、s in China Zeng Hong Qiu Hongli(Wuhan Light Industry Machinery Works, China Light Industry Machinery Company, Hubei Wuhan 430034)Abstract: The new technical processes of cyclopentane and carbon dioxide blown polyurethane foam system for the replacement of CFC-11 blowing agent in China are introduced
20、. Wuhan Light Industry Machinery Works makes two series complete sets of equipment related to the two blowing systems. The usage and structure features of the equipment are introduced. Keywords: foaming equipment; polyurethane foam; RIM; CFC-free; premixing 作者简介：曾红 高级工程师，华南理工大学化工机械系轻工机械专业毕业，现任武汉轻工业机
21、械厂副总工程师兼技术部部长，长期从事聚氨酯发泡成套设备的研发，主持开发的产品曾获国家级新产品和省级科技进步奖。2003 中国聚氨酯行业整体淘汰 ODS 国际论坛论文集368The Complete RIM Equipments for PU High Pressure CFC-free Foaming Process in China Zeng Hong, Qiu Hongli(Wuhan Light-industry Machine Manufactory of China Light-industry Machine Corporation, 430034)Abstract: This p
22、aper describes two new process routes in which cyclopentane and carbon dioxide are used as foaming agent to replace CFC-11 in China as well as the use and structural essentials of two types of complete equipments researched and developed according to the new process routes. Keywords: RIM, CFC-free,
23、premixing, polyol, isocynate, static mixer, batch, online In order to accelerate fulfillment of obligations of Montreal Memorandum of Agreement about Materials Consuming Ozonosphere, according to National Scheme of gradually Eliminating Materials Consuming Ozonosphere in China, foaming polyurethane
24、industry shall realize zero consumption of CFC-11 before 2010. Accordingly cyclopentane and carbon dioxide that dont damage ozonosphere at all are used as the foaming agent of hard and soft foaming polyurethane to replace CFC-11. In addition, according to new operate process, through digesting, abso
25、rbing, improving and innovating the advanced technology in the world, develop two types of complete RIM equipments for polyurethane high pressure CFC-free foaming process that separately use both foaming agents.I. Physical property of CFC-free (cyclopentane) used by complete RIM equipments for polyu
26、rethane high pressure CFC-free foaming process and comparison of them and CFC-11 are shown as Table 1. 1Table 1. Physical property of cyclopentane and comparison of them and CFC-11Foaming agent Molecular formulaRelative molecular mass Density(20)g/cm3Boiling pointGas heat conductivity (25)mW/(mK)Ste
27、am pressure (20)kPaExplosive limit v%(DOP valueCyclopentane C5H10 70 0.74 49 12.0 34 1.4-8.0 0CFC-11 CCl3F 137.4 1.49 24 8.5 None 1.0According to physical property of cyclopentane, the advantages of using cyclopentane as the foaming agent of hard foaming polyurethane are as follows: Dont damage ozon
28、osphere with good environmental protection performance, cheap and abundant resource; it is liquid in the room temperature; compared with CFC-11 whose density is same as foaming material, foaming agent used for cyclopentane is less because its molecular weight is light. Its shortages are: Inflammable
29、, easy to blast, equipment cost is high; its gas-phase heat conductivity is higher than that of CFC-11, thus the insulation performance of the foams is poorer. At present, manufacturers such as Haier, Kelon, Xinfei and Changling are using cyclopentane in the great batches as the foaming agent of the
30、 hard forming materials in the insulation layer of the refrigerators and ice-box. Production process route using cyclopentane as the foaming agent is as follows: 22003 中国聚氨酯行业整体淘汰 ODS 国际论坛论文集369According to the characteristics of cyclopentane and the process route, we develop complete RIM equipments
31、 for polyurethane high pressure CFC-free foaming process. In developing the equipment, pay special attention to developing the safety measures of explosion protection to guarantee the safe production. The complete RIM equipments for polyurethane high pressure CFC-free (cyclopentane) foaming process
32、consists of cyclopentane/polyolpremixing system, high pressure polyurethane CFC-free (cyclopentane) foaming machine and polyurethane CFC-free RIM foaming production line. Description of the structures of all units is as follows: 1. Cyclopentane / polyol premixing system (shown in Fig. 1):2According
33、to the characteristics of cyclopentane, newly develop the cyclopentane storage-tank of cyclopentane/polyol premixing system, which shall be placed underground if the conditions of the ground cant meet the safety requirement or the ambient temperature may be below 0, because that tank must be prevent
34、ed from impacting of external force without spark around it. Fig.1 Process flow diagram cyclopentane premixing systemSafety configurations of Cyclopentane/polyol premixing system are：Cyclopentane metering pump 2003 中国聚氨酯行业整体淘汰 ODS 国际论坛论文集370must have flameproof function; all devices that may contact
35、 cyclopentane or its gas shall be able to prevent the static sparks; motors and electric elements shall conform to the corresponding flameproof category; corresponding pipes, adaptors and valves shall be sealed tightly with bi-layer packing, pipes shall be equipped with the electric-operated cut-off
36、 valves; the containers filling with cyclopentane and its mixtures shall be filled with nitrogen to maintain pressure; mixing motor of the material tanks and mixing shafts are connected with magnetic couplings; the areas of the cyclopentane tank, metering, mixing and mixture tank are all equipped wi
37、th baffles or protection covers and installed the detection sensors, exhausting system and flameproof control system. The power of the flameproof control system is separated from the equipment power and the flameproof control is performed in three stages: The first stage is to control the fans for a
38、ir drafting during the normal operation, air exchanging flowrate in which is 10 times/second; 2the second stage is to control the fans for air drafting in high speed when the detection sensors finds that cyclopentane concentration reaches 20% of the bottom limit of blasting; the third stage is to 2d
39、isconnect the equipment power, shut the feeding valve and control the fans for air drafting in high speed when the detection sensors finds that cyclopentane concentration reaches 40% of the bottom limit of blasting to make the discharging content of cyclopentane to be controlled below the safety val
40、ue. 2. Polyurethane high-pressure CFC-free (cyclopentane) foaming machine (shown in Fig. 2)The material tank of cyclopentane/polyol mixture is filled with nitrogen to maintain pressure; mixing motor and mixing shafts of which are connected with magnetic couplings, the motor is the flameproof motor;
41、the tank is comparted with the partition covers with the detection sensors, exhausting system and flameproof three-stage control system; the motor mixture metering pump is the flameproof motor, motor and metering pump are comparted with the partition covers with the detection sensors, exhausting sys
42、tem and flameproof three-stage control system; isocynate tank and its metering pump neednt take flameproof measures; according to releasing sped and quantity of cyclopentane, the mixing head that can be for filling nitrogen is used so that the molding chamber is filled with nitrogen before injecting
43、 and mixture and isocynate impact and mix in high-speed during injecting. All devices contacting matures must prevent the sparks caused by static electricity and be grounded. Fig.2 Schematic diagram of polyurethane high-pressure CFC-free (cyclopentane) foaming machine3. Polyurethane CFC-free RIM foa
44、ming production line 2003 中国聚氨酯行业整体淘汰 ODS 国际论坛论文集371This production line can be divided into linear type, horizontal cycling type and vertical cycling type according to its layout forms. The stations of each line are decided according to the processing technology of the raw materials, running speed
45、and the output.a. Linear polyurethane CFC-free (cyclopentane) RIM foaming production line (shown in Fig. 3)Fig.3 Linear polyurethane CFC-free (cyclopentane) RIM foaming production lineThis production line is suitable for foaming and producing of the insulation layer of the casing body, which adopts
46、the fixed mould holder structure. The mould and holder are designed into a whole. The mixing head and the refrigerator, driven separately with the trolley, automatically identifies and moves among the holder, the oven and the lifting table for unloading. The line automatically performs work such as
47、preheating of casing body, loading it on the holder, pouring, casing and unloading. Safety requirements of pouring and curing area are: Mould boards and cores are heated with hot water or hot air; all devices such as motors and electric elements that may contact the released cyclopentane gas on the
48、holder must conform to the corresponding flameproof category or adopt safety-strengthening type ones with switching off poser after pouring. According to cyclopentane gas releasing curve (shown in Fig. 4), time of switching off power can last one minute. Mechanical movement parts must prevent the sp
49、arks due to static electricity and mechanical components are all grounded. The holder area is separated and the detection sensors, exhausting system and flameproof three-stage control system is installed.Fig.4 Cyclopentane gas releasing diagram when casing body is foamedb. Horizontal cycling polyurethane CFC-free (cyclopentane) RIM foaming production line (shown in Fig. 5)2003 中国聚氨酯行业整体淘汰 ODS 国际论坛论文集372Fig.5 Schematic diagram of vertical cycliing polyurethane CFC-free (cyclopentane) RIM foaming production lineThis produ
