The required information for pipe fittings includes the following:
Material and specification requirements: The materials of pipe fittings should comply with the current national product standards and design requirements. For example, the material of steel pipes can be Q235B, and spiral welded steel pipes require the use of rolled plates to manufacture welded steel pipes. Each pipe must be welded from a whole rolled plate, and two or more rolled plates must not be spliced together.
Appearance quality requirements: The surface of pipe fittings should be smooth, and defects such as folding, breaking, delamination, and lap welding are not allowed. For example, the surface of elbows should be smooth. If there are defects such as scars, scratches, and heavy skin, they should be ground. The ground areas should have a smooth transition and be colored or magnetic particle inspected.
Size and wall thickness requirements: The size, shape, weight, and allowable deviation of pipe fittings should comply with their product standards and design requirements. For example, the actual minimum wall thickness of the elbow should be greater than 12% of the nominal wall thickness of the main steel pipe to which it is connected, the wall thickness of the elbow should be at least 2 mm greater than the wall thickness of the connected steel pipe, and the inner diameter of the elbow should be consistent with the inner diameter of the steel pipe.
Testing and re-inspection requirements: For pipe fittings with re-inspection requirements in the design, or pipe fittings with doubts about quality, sampling should be carried out by the supervision engineer, and re-inspection should be carried out by a testing unit with corresponding qualifications. The re-inspection results should comply with the current relevant national product standards and design requirements.
Specific pipe fitting types and uses: Pipe fittings can be divided into connecting pipe fittings (such as flanges, unions, pipe clamps, etc.), pipe fittings that change direction (such as elbows, elbows), pipe fittings that change pipe diameter (such as reducers, reducing elbows), pipe fittings that add branches (such as tees, crosses), sealing pipe fittings (such as gaskets, raw tape) and fixed pipe fittings (such as clamps, towing hooks), etc. according to their uses.
Standards for pipe fittings of different materials: For example, cast steel pipe fittings can adopt ASTM/ASME A234 WPB and WPC standards, and cast iron pipe fittings and stainless steel pipe fittings also have corresponding standards and requirements.
