Carbon steel flange blind flange with the rapid development of domestic foreign minister pipeline construction, pipeline pressure test as one of the important link, before and after the test, pipeline ball-passing sweep line of each paragraph, number is usually 4 ~ 5 times. Especially after the pressure test, pipeline inside water is very difficult to clean, cleaning the number will be more. In the closed ball using repeated construction method of welding head, its existing problems: one is to increase the Labour strength of workers; 2 it is repeated welding consumables high head method, need more large equipment, the cost is high. For long distance pipeline pressure test to pass the ball after the scanning line, at the serve by repeated welding head method of high labor intensity big, consumables, need more large equipment, the problem of high cost, this paper proposes a new simple quick opening large blind flange plate construction method. The construction method of this article introduces the structure of the fast-opening blind, work steps and intensity. Through application on acerbity NingLan gas transmission pipeline engineering, prove fast-opening blind construction method than repeated three times welding head construction methods to improve work efficiency, not only reduce the labor intensity of workers, and reduce the cost. Carbon steel flanges need to do the preparatory work before measurement, according to the way and method of measurement, according to the specific situation of different measurement methods, ensure the accuracy of measurement.

To introduce the following carbon steel flange measurement: measure the preparation work before the:

1. According to the large flange position before measurement, should first draw the equipment in the large flange sketch, and numbered consecutively, so that the fixture installation to the number, according to the method and principle for installation, ensure the normal use.

2. Because when installed, the carbon steel flange diameter is different, possible hi-lo (different), the thickness of the gasket is not equal, so the processing of fixture should correspond to the side of the carbon steel flanges are not interchangeable, thus measurement by size and number is the key to the fixture processing and installation.

3. The measurement, the arrangement of three people, two of them were measured, proofread and fill out a form, measuring tool use vernier caliper, if there were no conditions available outside calipers and steel ruler. Measurement is a careful work, is the precondition of fixture installation, measure and record to prepare correct, carefully clear when you fill out a form. In the actual measurement work to mutual cooperate, can according to the principle of the right to cooperate and use.