论文快速发表网

社科类论文科技类论文医学类论文管理类论文教育类论文农林类论文新闻类论文建筑类论文文艺类论文法学类论文

EI Compendex Source List（2022年1月） EI Compendex Source List（2020年1月） EI Compendex Source List（2019年5月） EI Compendex Source List（2018年9月） EI Compendex Source List（2018年5月） EI Compendex Source List（2018年1月）中国科学引文数据库来源期刊列 CSSCI(2017-2018)及扩展期刊目录 2017年4月7日EI检索目录（最新） 2017年3月EI检索目录最新公布北大中文核心期刊目录 SCI期刊（含影响因子）

本站服务项目浅谈青年教师如何开展教科研大学青年教师如何处理教学和科

论文范文

Synergistic Effect of Latex Powder and Rubber on the Properties of Oil Well Cement-Based Composites 时间:2018-09-13 13:12   来源:未知   作者:admin   点击: 次 Abstract:The brittleness and the poor resistance to external load of oil well cement impede the development of oil and gas wells. To overcome these deficiencies, latex powder or rubber and their hybrid combinations were used to modify the oil well cement. The conventional properties, mechanical properties, and scanning electron microscopy (SEM) images of the modified cement were analyzed. In comparison with latex powder-incorporated cement and rubber-incorporated cement, a significant improvement of fluid loss, flexural strength, impact strength, and elasticity of the cement slurry was observed when using the hybrid combinations of 3 wt.% latex powder and 2 wt.% rubber, although this synergistic effect was not remarkable on the compressive strength and the thickening time. These evidences arose from the synergism between latex powder and rubber leading to the formation of a three-dimensional network structure and a flexible structure which subsequently improved the elasticity and toughness of cement stone. The improved elastic matrix has a buffering effect on external impact when the cement stone is subjected to an external load.
1. Introduction
Cementing is to inject cement slurry in between the annular of casing and the formation, and the cement sheath is formed after curing of cement slurry. The cement sheath has the main functions of suspending and protecting the casing, reducing and delaying the effect of formation on casing, improving the stress state of casing, and prolonging the service life of casing [1, 2]. Although Portland cement is a good material and achieves high compressive strength at low cost, its brittleness has been evidenced [3]. During the development of oil and gas wells, the cement sheath is subjected to various loads including the change of internal pressure and temperature and so on. Changes of various loads often lead to sealing failure, sustaining casing pressure, fluid channeling, and even wells scrapped [4]. The sealing ability of cement sheath is not only directly related to the effective implementation of drilling, completion, development, EOR, and other measures [5], but it also relies on the overall economic benefits of oilfield exploration and development.
   In order to achieve long-term integrity of the cement sheath, cement slurry should possess good construction performances, favorable mechanical properties, and sufficient flexibility [6].
Basically, the three main varieties of flexible materials used to improve the mechanical properties of oil well cement include fiber, latex, and rubber. As flexible materials, the various types of fibers are polypropylene fiber, carbon fiber, glass fiber, and asbestos fiber [3–7]. Fracture of cement stone occurs as a result of tensile stress of fiber which subsequently transfers the substrate through the adhesive force aims at limiting the expansion to fracture. Moreover, unavoidable fracture development leads to the stretching, the pulling out, or the failure of fiber as a consequence of consuming huge amount of energy which subsequently results in a brittle cementing material [8]. Additionally, the difficulty of fiber to be dispersed and its easiness to reunite in the cement slurry constitute another major drawback [9].
   Latex has been widely used in oil well cement as a performance improver in the following aspects [10–13]