摘要
分析了三层聚乙烯防腐管线双组分环氧涂层补口技术首次试用工程中遇到的聚乙烯层倒角上环氧涂层大量开裂的主要原因,探讨了该补口新技术的可行性.结果表明,涂层在固化过程中因温度低而出现的裂纹,只属于工程管理疏忽问题;温度变化的频率和温差幅度以及倒角上的鼓棱或涂层内的刷痕等可能是涂层开裂的综合性原因;涂层固化后不开裂,这种补口方式就有约束管体聚乙烯层变形的功能;涂层固化后只是倒角上边缘开裂而下边缘不开裂,则对管线防腐系统功能无太大影响;在该补口技术的推广使用初期,应在确保管体环氧底层伸出倒角边缘一段距离的同时用冷缠胶带等包缠倒角周围.
The authors analyzed the main causes related to the concern that a lot of epoxy coatings on PE chamfers cracked during the first trial construction of two- component epoxy coating used on the weld joint coating of 3PE pipeline, probed and discussed the feasibility of this new joint coating technique, the main conclusions are as follows： if the coating cracks during the curing course were caused by lower ambient temperature, the concern should be the negligence of quality control in relation with project management; it is possible that the frequency of temperature change, the amplitude of temperature difference and the convex ridge on chamfers or the brush trace in coatings are the comprehensive causes for the coating cracks; coatings did not crack after being cured, this kind of weld joint coating mode will have the function for restricting the deformation of PE layer; coatings crack only at the top ridge of chamfers and do not at the bottom edge after the coatings are cured, it do not have too serious effect on the function of pipeline anti- corrosion system; at the beginning period of generalization and application of this new weld joint coating technique, the chamfers should be covered by wrapping adhesive tapes or others around it at the same time that a certain distance of the epoxy primer layer protruding out of the PE layer is ensured;the mechanism of epoxy coating cracking at chamfer surface should be lucubrated further.
出处
《腐蚀科学与防护技术》
CAS
CSCD
北大核心
2006年第4期281-284,共4页
Corrosion Science and Protection Technology
关键词
3层PE
管线
防腐
双组分环氧
涂层
补口
温度开裂
3-layer PE, pipeline
corrosion prevention
two-component epoxy
paint
coating
field jont coating
temperature cracking
