Purchasing the matters needing attention of gas ball valve
Publish Time: 2016-09-26 Origin: Site
Now more and more domestic gas pipeline, and today to introduce purchasing gas ball valve precautions:
1, as soon as possible to reduce the valve structure height (refer to the centerline of the valve flow section to height) on the top of the valve, to reduce the depth of buried pipes.
2, at the top of the valve should be equipped with fully enclosed open-close indicator, is advantageous for the check valve state, is one of the important conditions for safe operation.
3, full size design, reduce the flow resistance, facilitate sweeper through a pipe or pipe detector, should also meet the constantly lose enclosed tapping machine on the pipe opening.
4, reliable sealing performance, soft seal valve under the nominal 1.1 times the rated working pressure are not allowed to have any internal leakage detection, hard seal valve under the nominal 1.1 times the rated working pressure allows the internal leakage of less than 13 dnmm3 / s.This requirement is strict, such as: within 500 mm of the gas valve nominal diameter of leakage is not greater than 9 ml/min, the leakage is absolutely not allowed.
5, the use of the underground pipe network of gas valve shell shall be corrosion resistant, Suggestions according to the transfer medium in pipeline and the use of pressure with different shell material.
6, the valve parts design should consider to use less maintenance or free maintenance structure, minimize maintenance and maintenance workload, reduce the enclosed by the valve overhaul and maintenance road traffic.
7, the vast majority of underground pipeline valve for artificial opening and closing, the requirements of the valve opening and closing torque is small, the entire circle number is reasonable, can cut off the gas source as soon as possible after the accident.