4　Inspection of Pipes,Pipe Fittings,Pipe Accessories and Valves

4.1　General Requirements

4.1.1　Pipe,pipe fittings,pipe accessories and valves must have the certificate of compliance and valid certificate of product quality test of the manufactory.The related data shall meet the current national or industrial standards.

4.1.2　Before the use of pipe,pipe fittings,pipe accessories and valves,the specification,material and technical parameters shall be verified according to the design requirements.

4.1.3　Before the use of pipes,pipe fittings,pipe accessories and valves,visual examination shall meet the following requirements.

1　There shall be no defects such as cracks,shrinkages,slag inclusions,sand burning,lamination,lack of weld or double-skin.

2　The surface shall be smooth without any sharp scratches.

3　The depth of surface depressions shall not exceed the negative deviation of nominal wall thickness.After cleaning,the actual wall thickness shall not be less than the allowable minimum value.

4.1.4　Before using alloy steel pipes,pipe fittings,pipe accessories and valves,the positive material identification(PMI)shall be carried out one by one with marking the material on their surface.

4.1.5　The seam pipes and pipe fittings with the design pressure above 0.1MPa shall have the weld inspection report from the manufacturer.

4.1.6　Before pipe construction,chemical composition analysis results of pipes,pipe fittings and pipe accessories shall be verified according to the quality certificate from the manufacturer and shall meet the requirements of current national or industrial standards.It can be implemented according to Annex B.If the quality certificate is not complete or the quality is in question,the supplier shall be required to complete the quality certificate or re-examine the chemical composition.

4.1.7　After the arrival of steam conduits,oil tubes and other setting tubes from the manufacturer,they shall be confirmed with no damage during the transportation,and the tube inner wall surface is clean without rust.