Welding of flange connection ration of seamless steel tube

The flange connection ration of seamless steel tube is considered by straight pipe and pipe fittings, and all the work contents of preloaded and installed are considered.

　　If the pipe installation of flange valves, only the calculation of valve installation costs, should not repeat the calculation of flange installation fee. The quota does not include the number of main materials of pipe fittings, flanges and bolts, and shall be calculated separately according to the design requirements: Galvanized steel tubes and fittings and external transportation costs should be calculated separately.