High pressure pipe installation

The requirements for high-pressure pipeline installation are similar to those for medium- and low-pressure pipeline installation, but the requirements are higher and the regulations are stricter. Therefore, in addition to meeting the requirements for medium- and low-pressure pipeline installation, the following requirements should also be followed. Since the wall of high-pressure pipes is thicker, sand filling is generally not required when bending.
The high-pressure pipe sections, pipe fittings, fasteners and valves used for installation must be inspected and qualified, and accompanied by corresponding technical certification documents. After being transported to the site, they should be properly stored, clearly marked and neatly placed. Before installation, the inner and outer surfaces should be wiped clean, and the internal channels should be checked for foreign matter and whether they are unobstructed. Check whether the roughness of the pipe mouth sealing surface and the sealing gasket meets the requirements. There should be no scratches (especially radial scratches) or spots on the sealing surface that affect the sealing performance. Except for pipes that are required to be degreased, the pipe mouth sealing surface and the sealing gasket should be coated with engine oil, butter or white vaseline for protection.
The threaded part of the high-pressure pipe end that has passed the inspection, except for pipes that are required to be degreased, should be coated with molybdenum disulfide grease or graphite engine oil blending agent for protection.
When installing the pipeline, it should be fixed with a formal pipe rack. On the pipe rack in contact with high-pressure pipes and pipe fittings, a protective sleeve should be installed according to the design requirements. When installing the high-pressure flange, the chamfer of the pipe end thread should be exposed. When installing the gasket, do not use wire to hang it. Grease the pipe mouth and gasket in advance, and the soft metal high-pressure gasket should be accurately placed in the sealing seat.
The flange bolts should be tightened symmetrically and evenly, and should not be excessive. After the bolts are tightened, the two flanges should remain parallel and concentric. The threads exposed outside the nut should be 2~3 buckles, at least not less than 2 buckles, and the exposed length of each bolt should be basically the same.
During the installation process, strong pulling, strong pushing, strong twisting or modifying the thickness of the gasket should not be used to compensate for manufacturing or installation errors. If the pipeline installation work cannot be carried out and completed continuously, the open pipe mouth should be closed in time. The parts of the instrument sampling part on the pipeline should be installed at the same time as the pipeline.
When the alloy steel pipe is corrected for local curvature, its heating temperature must be controlled below the critical temperature of the steel.
After the pipeline system is installed, the steel stamp marks on the pipeline should be fully checked. If it is found that the steel stamp is missing somewhere, it should be added in time based on the original basis.