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青海省1975年～1978年期间,在东部浅山区进行自压喷灌试验,管材多为聚氯乙烯(有少部分聚丙烯管),管道联接采用承插粘接方法。干支管三通、闸阀、竖管、竖管三通等多用塑料,塑料管和铁件联接采用热插接。这种管件及其联接法在低压区是可行的,但位于30米以上的中高压水头区,在管内水压较大时会出现脱节漏水现象,严重时土地湿陷,管道断裂,影响喷灌。为改进喷灌设备的管道联接技术,1982年～1984年在湟中县云谷川灌区的
During the period from 1975 to 1978 in Qinghai Province, self-pressure sprinkler irrigation was conducted in the shallow eastern mountainous area. Most of the pipes were made of polyvinyl chloride (with a small part of polypropylene pipes). Pipe joints were welded by socket method. Dry branch tee, gate valve, standpipe, standpipe tee and other multi-purpose plastic, plastic pipe and iron connection using hot plug. This pipe and its connection method is feasible in the low pressure area, but located in the high-pressure head area of more than 30 meters, there will be out of line water leakage in the pipe when the water pressure is large, when the soil collapses seriously, the pipeline ruptures and affects the sprinkler irrigation. In order to improve the sprinkler pipe coupling technology, 1982 to 1984 in Langzhong County Valley Valley irrigation