PR1型聚乙烯缠绕结构壁管的环刚度计算方法研究

聚乙烯缠绕结构壁管的环刚度是其抵抗径向变形的重要性能参数,影响着其外压承载能力。以PR1型截面的埋地聚乙烯缠绕结构壁管为例,对管道轴向截面进行截面单元划分,同时,综合考虑截面发生变形、局部材料迁移等情况,建立截面单元的简化计算模型,并对截面单元关键尺寸参数进行修正。在此基础上,研究PR1型聚乙烯缠绕结构壁管环刚度的计算方法;通过实例验证了PR1型聚乙烯缠绕结构壁管的截面单元的形心、惯性矩以及环刚度计算方法的准确性,相关研究方法与结果将对聚乙烯缠绕结构壁管的设计、生产与使用以及其他复杂截面管道的环刚度计算提供一定的参考作用。     

石家庄宝石电子集团有限责任公司300／3000聚乙烯缠绕结构壁管材成套设备通过鉴定

石家庄宝石电子集团有限责任公司最新研制开发的300/3000聚乙烯缠绕结构壁管材成套设备已于2002年6月18日通过河北省经济贸易委员会组织的新产品鉴定。该设备主要性能指标均达到国外同类产品先进水平，为国内首创。300/3000聚乙烯缠绕结构壁管材成套设备是在消化、吸收德国进口设备的基础上，联合中科院自动化所和核工业第四设计研究院共同研制开发完成的。该成套设备采用热挤塑缠绕成型工艺，工艺新颖独特，控制系统采用西门子S7-300集中控制大屏幕液晶显示，工艺布局紧凑。可生产VW、SQ、PR三种系列的聚乙烯缠绕结构壁管材及管件，管材…     

高密度聚乙烯管材焊接工艺

本文扼要介绍了ＨＤＰＥ管材的热熔焊接工艺，并通过实例，说明焊接工艺的整个过程．     

一种矿用新型增强PE结构壁管材

基于环刚度定义(ISO 9969—2007),设计制造了一种以纤维增强高密度聚乙烯(HDPE)为原料,用于煤矿井下瓦斯抽采的新型"工字钢"缠绕结构壁管材,并对其性能进行了检测。结果表明:同传统管材相比,新型管材具有更高的环刚度以及良好的耐温性能。另外,在满足要求的条件下,同规格新型管材的单位质量显著降低,最高减幅可达44.4%。     

高密度聚乙烯缠绕增强管的应用

介绍了高密度聚乙烯（HDPE）缠绕增强管的种类，性能，生产工艺及特点等。因HDPE缠绕增强管具有输水量大，铺设简便等优点，可适用于远距离低压输水，城市给排水，海水输送，以及农田灌溉等输送工程。举例阐述了使用HDPE缠绕增强管的优化，并展望了HDPE缠绕增强管的发展前景。     

管材用高密度聚乙烯管材树脂研究进展

聚乙烯管材以其优异的性能广泛应用于供水、燃气输送等领域,HDPE管材树脂是近年来的研发重点。本文综述了高密度聚乙烯管材树脂的应用领域、市场情况,详细介绍了其分子结构、性能特点以及国内外高密度聚乙烯管材树脂的研究进展。     

高密度聚乙烯管材拓展新应用

日前,扬子石油化工股份有限公司(简称扬子石化)高密度聚乙烯(HDPE)管材在江苏省盐城市盐城沿海化工园污水处理管道项目招标中,一     

基于NSGA-Ⅱ的埋地聚乙烯缠绕结构壁管的优化设计方法

设计了一种复杂截面缠绕结构壁管的优化设计方法，以实现管径环刚度、截面结构尺寸和管道质量的最优化配置。以工程设计中的性能要求、最佳经济效益为优化目标，以可制造性要求、结构尺寸合理性要求等为约束条件，实现基于精英策略非支配排序遗传算法-Ⅱ（NSGA-Ⅱ）的埋地缠绕结构壁管截面优化设计，即在管道公称直径、材料模量、环刚度取值范围等条件已定的情况下，获得缠绕结构壁管的最优截面类型和截面尺寸。结果表明，该方法满足复杂截面的缠绕结构壁管在工程设计中的选型和优化设计，同时为其他管道优化设计提供一定的参考作用。     

高密度聚乙烯管材性能的研究

对不同类型催化剂生产的高密度聚乙烯管材料HD4801-1、HD4801-2进行性能分析。试验表明：HD4801-1的相对分子质量、熔体强度、氧化诱导期大于HD4801-2的,但剪切黏度小于HD4801-2的,HD4801-1的加工性能优于HD4801-2的。     

快速交联高密度聚乙烯管材

相比其他交联方法,硅烷交联法的优势十分显著。但是,制得的管材在进行水交联时。反应时间太长,面且设备投资成本很大。为此,上海交通大学开发出了一种新的“快速硅烷交联聚乙烯技术”,可直接生产出无需水煮的快速硅烷交联聚乙烯管料,从而实现了聚乙烯管的快速交联。     

Morphology of high-density polyethylene pipes stored under hydrostatic pressure at elevated temperature

The morphology of unimodal and bimodal high-density polyethylene (HDPE) pipes during a hydrostatic pressure test was studied in detail using ¹H solid-state NMR. Characterizing the changes of the molecular network during such a test is of key importance for understanding the long-term properties of different HDPE pipe grades. The changes in amount, thickness, and molecular mobility of the crystalline phase, the interface, and the amorphous phase of the two pipe grades with the storage time have been quantified for the first time. The most sensitive microscopic parameter to storage is the molecular mobility of the amorphous phase, with the strongest changes shown by the unimodal HDPE. The density of the tie-molecules is not the main factor controlling the very different behavior of the two pipe grades, but rather it is the density of the entanglements. The NMR results offer unprecedented insights into the changes in the molecular network and support existing deformation models.     

管材专用高密度聚乙烯的研究进展

综述了国内高密度聚乙烯(HDPE)的生产装置及工艺。采用双峰聚合工艺使短支链更多地分布在高相对分子质量部分是HDPE管材从PE80级升至PE100级的主要原因。管材的耐环境应力开裂性能随HDPE相对分子质量减小而下降,提高短支链含量可提高管材的耐环境应力开裂性能。HDPE的相对分子质量越高,管材抗裂纹扩展性能越好,将短支链分布在高相对分子质量端可提高抗裂纹扩展性能。     

高强超薄薄膜料7000 F长周期生产探索

从工艺、设备等方面对生产高密度聚乙烯产品7000F的难点进行了统计分析，主要存在质量不稳定、低聚物量大、易堵塞工艺管线、离心机故障率高、己烷汽提塔系统易堵塞、造粒困难等问题，并对此提出了相应对策。通过技术改造、优化工艺参数等手段，使7000F生产周期在1个月以上，基本达到了长周期稳定生产的目的。     

Recycling of crosslinked high-density polyethylene through compression molding

Crosslinkable high-density polyethylene (XHDPE) is used to manufacture large and rigid products such as fuel tanks using rotomolding. Currently, defective and postconsumer parts are not recycled and sent to landfills. Hence, recycling of this material through compression molding is the objective of this study. Thermal analysis revealed that the extent of crosslinking varied across the thickness of the rotomolded part due to the role played by oxygen in air. Despite the crosslinking, the recycled XHDPE (RXHDPE) could be remelted with higher viscosity than the virgin XHDPE (VXHDPE). Consolidation studies indicated that both the RXHDPE and the VXHDPE could be compression molded to a density of 0.952 g cm⁻³. However, higher consolidation stress is required for the RXHDPE when compared to the VXHDPE to realize the same density. The RXHDPE, compression molded at 1.6 MPa and 230 °C, had properties similar to those of the VXHDPE molded at 0.32 MPa. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 48145.     

低压高密度聚乙烯装置动态模拟模型开发策略浅谈

讨论了应用通用流程模拟软件AspenPlus、聚合物模拟软件PolymersPlus及动态模拟软件AspenDynamics开发低压高密度聚乙烯装置反应系统动态模型的策略和方法。     

氯化聚乙烯工艺技术的比较

介绍了氯化聚乙烯的几种生产工艺，比较了釜式气固相氯化工艺、溶液法工艺、盐酸相悬浮工艺、水相悬浮法工艺，认为国外开发的水相悬浮法工艺优点显著。     

高密度聚乙烯管耐氯氧化试验系统设计

为了研究高密度聚乙烯（PE?HD）管的耐氯氧化性能，基于ASTM F2263标准，设计了一种封闭循环试验系统，可在流动状态下通过改变温度、压力和有效氯含量加速试样的氧化失效。结果表明，该系统可独立测试24根DN 20的PE?HD管状试样，可编程逻辑控制器（PLC）作为控制主机可以控制管路的压力、温度和流量，再加上耦合各传感器，可实现可视化的人机界面，内置的报警系统可保证试验的安全可靠。本试验系统可用于对PE?HD输水管的耐氯氧化性能进行评价。     

Wettability and interfacial phenomena investigations on high-density polyethylene and petroleum coke

An in-depth wettability and interfacial phenomena investigation was carried out to study interactions between high density polyethylene (HDPE) and petroleum coke. The aim is to investigate the effect of temperature and contact times on possible interactions and adhesion characteristics for partially substituting coal-tar pitch binder with waste polymers. Using a sessile drop arrangement, experimental assemblies consisting of ground HDPE and a petroleum coke substrate were heat treated in the temperature range of 150–350°C for 15–60 min. Contact angles between molten HDPE and petroleum coke surface and depth of penetration of HDPE into petroleum coke substrate were measured. The highest contact angle (131.5°) was observed at 250°C after 15 min. and lowest contact angle (30.9°) was observed at 350°C after 60 min. Highest penetration depth (75 μm) was observed at 350°C after 60 min and lowest penetration (13 μm) at 200°C after 15 min. Analysis of results showed that increasing time and temperature of heat treatment had a significant impact on the interactions of molten HDPE with petroleum coke. Longer residence time and higher temperatures increased the extent of melting of HDPE, which in turn resulted in improved wettability and deeper penetration into petroleum coke substrate. HDPE was found to bind and adhere strongly with petroleum coke. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Morphology of extruded high-density polyethylene pipes studied by atomic force microscopy

Atomic force microscopy (AFM) was used to study the structure of extruded polyethylene (PE) pipe. During extrusion, the outer surface of the pipe was cooled with water. Two cross sections, parallel and transverse to the extrusion direction, were examined in order to spatially follow the structural development during extrusion. The morphology revealed was spherulitic, and the spherulites had a mostly banded appearance when viewed under the AFM. We were not able to distinguish an oriented skin layer at the surface of the pipe, either by AFM or polarizing microscopy. The changes in the pipe's structure resulting from the cooling conditions were found to be rather gradual, and no clearly defined zones were observed. A slight orientation towards the extrusion direction was detected only in the area of the pipe crystallized under the lowest degree of undercooling. Measured spherulitic size, band period, and lamellae thickness showed a gradual increase in their values from the cooled to the noncooled surface of the pipe. Transmission electron microscopy (TEM) was used to verify the band period and lamellae thickness measurements done by AFM. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 515–523, 1997     

PET料仓刚性环耳座的计算

以聚酯装置中PET料仓刚性环耳座的设计为实例,运用NB/T 47003.1-2009《钢制焊接常压容器》的计算方法进行强度计算,介绍了刚性环耳座的计算方法。