津华线埋地管道防腐涂层——三层PE

从天津港-华北石化原油管道工程管道防腐涂层的选择出发,介绍了埋地管道三层PE防腐涂层的特点,分析了埋地管道三层PE防腐涂层各部分的化学组成。指出埋地管道三层PE中,环氧粉末起主要防腐作用,聚乙烯层的作用是阻挡外界介质,胶黏剂是"桥梁",可以将熔接环氧粉末和聚乙烯有机连接在一起。最终,项目在特殊地段选择了三层PE防腐层,在一般地段选择了环氧粉末防腐层。     

耐高温环氧涂层在海底管道防腐中的应用研究

随着深水油气田勘探与开发地不断深入,采出液温度通常处在80℃~150℃之间,普通熔结环氧粉末已无法为管道提供安全可靠的防腐涂层。为确保FBE涂层的长期服役性能,一般要求环氧粉末的Tg应至少高于运行温度5~20℃。本文是在耐高温环氧涂层评价体系建立的基础上,将海底管道环氧涂层的耐温性提高至110℃,从原材料性能检验、涂敷工艺试验、涂层性能检测及耐高温环氧涂层在番禺35-2/35-1项目深水高温管道防腐工程上的应用等方面进行论述。     

环氧粉末涂层管体的对接焊缝现场外补口技术

环氧粉末管道焊缝现场外补口技术,解决了环氧粉末涂层管体现场外补口的难点。全套工艺和装备满足了野外施工现场外补口的工序要求,工艺方法先进,补口质量及各项指标均达到国内外管体涂层标准,主要设备设计合龟、性能可靠、操作方便、安全省力,该技术适用于φ377～φ720mm管道外补口,补口后形成的防腐护层坚韧密实、防腐性能好。     

SEBF重防腐环氧粉末涂料在地下管道中的应用

研制的SEBF重防腐环氧粉末涂料克服了传统管道防腐涂料的缺陷，其性能达到国外同类涂料水平，满足了地下和水下管道的防腐要求。介绍了SEBF涂料的组成及其涂装方法。列举了该涂料在各种介质中的耐化学腐蚀性。讨论了地下管道涂层性能的各项要求，以及管道接头的防腐和解决方法。     

埋地钢质管道3PE防腐材料及其粘接机理

介绍了埋地钢质管道3PE防腐体系所用的粉末环氧、胶粘剂和聚乙烯的分子结构、性能及其分子中的活性基团,论述了粉末环氧和胶粘剂的反应过程以及胶粘剂和聚乙烯的熔接过程,探讨了3PE涂层的各层能够形成一个整体、表现出优异性能的机理。     

一种无溶剂环氧酚醛管道补口涂料的性能评定

在管道干线防腐层技术中,三层结构聚乙烯(3PE)防腐层和熔结环氧(FBE)是两种非常成熟并广为应用的技术。而在管道补口防腐层技术中,国内主要采用聚乙烯热收缩带为主,国外补口材料有多种类型,包括液体涂料,熔结环氧粉末和聚烯烃涂层等。管道补口防腐层关系到整条管线的防腐质量,也是导致管道失效的薄弱环节。介绍了国外关于管道补口防腐层的短期和长期性能的评定方法以及无溶剂环氧酚醛124在该评定方法下的产品性能。     

钢顶管工程外防腐技术的研究与应用

钢顶管外防腐因顶进过程涂层摩擦、难以修补而具有独特要求,该文综合比较环氧煤沥青涂层、环氧玻璃鳞片涂层和熔结环氧粉末涂层这三种涂层的性能,价格,施工要求等因素,选用熔结环氧粉末涂层作为南汇支线钢顶管外防腐涂层;经过工程的验证,此材料的选用可以提高钢顶管防腐涂层的质量和适用性,保障工程的安全运行。     

无溶剂环氧涂料在油气管道内涂层中的应用

传统管道内用涂料常采用溶剂型环氧涂料,在管道内防腐与降低摩擦阻力等方面起重要作用,但溶剂型涂料存在一定弊端,如有机溶剂挥发造成的环境污染、火灾隐患、涂层质量下降等.开发了新型无溶剂环氧涂料,涂层的性能优异,较小的粗糙度,较低的表面能,在油气运输过程中有积极的减阻增输效果.     

天然气管道内减阻涂层防腐研究

针对天然气管道内减阻涂层的防腐技术问题,结合我国天然气管道内减阻涂层的使用现状,对内减阻涂层的防腐技术要求进行深入分析,对内减阻涂层防腐材料进行对比优选。研究表明:天然气管道内减阻涂层对防腐技术的要求相对较高,因此需要对防腐材料进行合理的对比优选,对常见的四种防腐材料进行对比后发现,双组分液体环氧涂料的性能相对较好,且能满足内减阻涂层防腐技术要求,因此推荐使用双组分液体环氧涂料。     

海底管道三层聚烯烃防腐涂层系统FBE的质量控制

熔结环氧粉末(FBE)作为海管用三层聚烯烃防腐涂层的重要涂料,决定着防腐涂层的整体质量。本文主要从熔结环氧粉末的检验、涂覆、验收等方面来介绍海管防腐涂层的质量控制。通过工程案例介绍质量风险。通过熔结环氧粉末的材料特性与涂层施工工艺、涂层服役环境和熔结环氧粉末的技术要求,阐述了海管防腐层用熔结环氧粉末的质控要点。     

管道防腐用环氧粉末涂料及其新进展

介绍了管道防腐用环氧粉末涂料的组成及固化体系,综述了其在国内外的发展状况。结合国产管道防腐用环氧粉末涂料存在的问题和粉末技术的最新发展,探讨了提高国产管道防腐用环氧粉末涂料综合性能的技术途径。     

Strength Analysis of Adhesively-Bonded Tubular Single Lap Steel-Steel Joints Under Axial Loads Considering Residual Thermal Stresses

The static tensile load bearing capability of adhesively-bonded tubular single lap joints calculated using linear mechanical adhesive properties is usually far less than the experimentally-determined one because the majority of the load transfer of adhesively-bonded joints is accomplished by the nonlinear behavior of the rubber-toughened epoxy adhesive

In this paper, both the nonlinear mechanical properties and the residual thermal stresses in the adhesive resulting from joint fabrication were included in the stress calculation of adhesively-bonded joints. The nonlinear tensile properties of the adhesive were approximated by an exponential equation which was represented by the initial tensile modulus and ultimate tensile strength of the adhesive.

From the tensile tests and the stress analyses of adhesively-bonded joints, a failure model for adhesively-bonded tubular single lap joints under axial loads was proposed.     

Tensile Strength of Joints Bonded With a Nano-particle-Reinforced Adhesive

In order to improve the tensile lap shear strength of adhesively bonded joints, nano-particles were dispersed in the adhesive using a 3-roll mill. The dispersion states of nano-particles in the epoxy adhesive were observed with TEM (Transmission Electron Microscopy) with respect to the mixing conditions, and the effect of nano-particles on the mechanical properties of the adhesive was measured with respect to dispersion state and weight content of nano-particles. Also the static tensile load capability of the adhesively bonded double lap joints composed of uni-directional glass/epoxy composite and nano-particle-reinforced epoxy adhesive was investigated to assess the effect of nano-particles on the lap shear strength of the joint. From the experimental and FE analysis results, it was found that the nano-particles in the adhesive improved the mechanical properties of the adhesive. Also the increased failure strain and the reduced CTE (coefficient of thermal expansion) of the nano-particle-reinforced adhesive improved the lap shear strength of adhesively bonded joints.     

Strength of Adhesive Joints Immersed in Different Solutions

Polymethyl methacrylate/epoxy/polymethyl methacrylate (PMMA/epoxy/PMMA) and aluminium/ epoxy/aluminium joints were immersed in different reagents including saline water, distilled water, sodium hydroxide solution, and sulphur dioxide solution. The joints were immersed in the reagents with and without a constant tensile load. The joints were also tested in air. Four loading periods were selected. At the end of each loading period, the joints were loaded in a tensile testing machine until failure. The results of the tests showed that the tensile strength of the aluminium joints was reduced, while that of polymethyl methacrylate was increased after immersion. The same results were obtained regardless of whether the submerged joint was loaded or not. Moreover, corrosion was found on the aluminium joints immersed in the sodium chloride solution and sulphur dioxide solution.     

Utilization of Granite Powder as Filler in PC-Toughened Epoxy Resins: Studies on Physico-Mechanical Properties

The present study reports the possibility of using granite powder, an industrial waste with no end use, as potential filler in polycarbonate (PC)-toughened epoxy resin. Testing data for the physico-mechanical properties such as tensile, flexural, density and void content of the composites, according to the filler loading were catalogued. Incorporation of waste granite powder in toughened resin enhances the mechanical properties when compared to neat epoxy, but reduces significantly with respect to toughened resin matrix.     

纳米SiO2/竹纤维/环氧树脂复合材料性能研究

将竹纤维加入到环氧树脂中以形成增强环氧复合材料,研究了竹纤维竹粉和纳米二氧化硅（SiO2）对环氧树脂的力学性能和耐溶剂浸蚀性能的影响。竹纤维含量为15%时,竹纤维/环氧树脂的冲击强度比纯环氧树脂提高50%。纳米SiO2能同时增强和增韧竹纤维/环氧树脂,并提高其耐溶剂浸蚀性能,纳米SiO2含量为4%时,纳米SiO2/竹纤维/环氧树脂三元复合材料的冲击和拉伸强度分别比未添加纳米SiO2的竹纤维/环氧树脂提高40%和30%。当纳米SiO2/竹纤维/环氧树脂的质量比为4/15/85时,三元复合材料的综合性能较好。     

Influence of Fabrication Residual Thermal Stresses on Rubber-toughened Adhesive Tubular Single Lap Steel-Steel Joints under Tensile Load

The tensile load bearing capability of adhesively-bonded tubular single lap joints which is calculated under the assumption of linear mechanical adhesive properties is usually much less than the experimentally-determined because the majority of the load transfer of adhesively-bonded joints is accomplished by the nonlinear behavior of rubber-toughened epoxy adhesives. Also, as the adhesive thickness increases, the calculated tensile load bearing capability with the linear mechanical adhesive properties increases, while, on the contrary, the experimentally-determined tensile load bearing capability decreases.

In this paper, the stress analysis of adhesively-bonded tubular single lap steel-steel joints under tensile load was performed taking into account the nonlinear mechanical properties and fabrication residual thermal stresses of the adhesive. The nonlinear tensile properties of the adhesive were approximated by an exponential equation which was represented by the initial tensile modulus and ultimate tensile strength of the adhesive.

Using the results of stress analysis, the failure criterion for the adhesively-bonded tubular single lap steel-steel joints under tensile load was developed, which can be used to predict the load-bearing capability of the joint. From the failure criterion, it was found that the fracture of the adhesively-bonded joint was much influenced by the fabrication residual thermal stresses.     

Investigation of the Mechanical Properties of Interphases in Adhesively Bonded Epoxy-Aluminum Joints by Localized Micro Extensometry

In recent papers it has been reported that epoxide-based adhesives form so-called interphases in adhesive joints. The properties of these interphases play an important role concerning the performance and durability of structural adhesive joints under detrimental service conditions. In this paper, the formulation of a basic epoxy adhesive and a methodology for gaining insight into the local mechanical properties of polymer interphases in structural adhesive joints made with ambient temperature curing epoxy adhesive are presented. The localized strain analysis in the cross-section of shear-loaded adhesive joints is accomplished by combining a high precision micro tensile tester with a digital microscope and by developing a method for preparing, marking, and digitally tracking the local deformations in a micro shear specimen.     

Reuse of cured epoxy as a reinforcement in an epoxy composite

This article discusses the reuse of a thermoset‐based epoxy polymer. In this method, cured epoxy polymer is ground to powder of particle size ranging from 1 to 30 μm. The ground epoxy is then filled in an epoxy polymer to form an epoxy–epoxy composite system using both room and high temperature processing. The amount of filler material was varied from 1 to 10 wt% in the epoxy matrix. Rheology and tensile properties test were then performed. The result shows that the room temperature‐processed epoxy composites (above 5 wt% of powders) resulted in the formation of voids, agglomeration of particles, and reduced degree of cure leading to a decrease in tensile properties. These drawbacks (voids, agglomeration, and low degree of cure) were correspondingly absent in composites processed at high temperature. Results from this work suggest that the thermoset polymer can be reused effectively with minimal changes to the unfilled resin properties. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers