材料：天然气管道工程材料的选择是否合理，产品是否合格，材料是否经过测试

MATERIALS: Materials Engineering gas pipeline is reasonable, whether the product is qualified, whether the material tested, storage and use is appropriate, etc., will directly affect the overall quality of engineering materials pipeline. The impact of the project the appearance and perception, affect the function of the project, the project affect the safe use. Thus, the material used in the project, i.e. pipes, pipe joints, welding quality control material should meet the following requirements:

Materials: Whether the choice of natural gas pipeline engineering materials is reasonable, whether the product is qualified, whether the material has been tested, whether the storage and use is appropriate, etc., will directly affect the overall quality of pipeline engineering materials. Affects the appearance and perception of the project, affects the use of project functionality, and affects the safety of the project's use. Therefore, the quality control of the materials used in the project, i.e. pipes, fittings, and welding materials, should meet the following requirements:

Materials: whether the selection of natural gas pipeline engineering materials is reasonable, whether the products are qualified, whether the materials are tested, whether the storage and use are appropriate, etc., will directly affect the overall quality of pipeline engineering materials. It affects the appearance and perception of the project, the use of project functions and the safety of project use. Therefore, the quality control of materials used in the project, i.e. pipes, pipe joints and welding materials, shall meet the following requirements: