What are the important factors that determine the quality of spiral steel pipe?

The five elements of controlling project quality:
Construction personnel quality, machinery and equipment, raw materials, construction methods and construction environment. The quality control of raw materials is an important part of ensuring project quality. Therefore, the control of the quality of construction raw materials must not be careless.
The main materials used in the project (such as steel plates, fittings, appliances and equipment) must have Chinese quality certification documents. Specifications, models, and performance test reports should meet national technical standards or design requirements. When entering the site, inspection and acceptance shall be done and checked and confirmed by the supervision engineer.
Check whether the physical and mechanical properties of the steel plate meet the design requirements.
Electrode selection and storage:
“Section 4.2.6 of the Code for the Acceptance of Construction Quality of Buildings for Water Supply and Drainage and Heating” GB50242-2002 Article 4.2.6 stipulates: The external dimensions of the weld shall conform to the requirements of the drawings and process documents, and the height of the weld shall not be lower than the surface of the base metal. Welds and parent metal Should be a smooth transition. The surface of the weld and heat-affected zone should be free from cracks, fusion, incomplete penetration, inclusions, craters, and porosity.
First, the chemical composition and mechanical strength of the welding rod should be the same as those of the parent metal. In order to ensure the safety of the welding workpiece, under the premise of meeting the safety conditions, consider the working conditions and the craftsmanship.
Do not use wet electrodes during welding. If the workpiece is welded with a damp electrode, the workability of the workpiece will be deteriorated, and the arc will be unstable, the spatter will increase, and the weld will be prone to defects such as pores and cracks. Therefore, the electrode is generally placed in an oven before drying, placed in a drying cylinder or a heat-insulating tube, ready for use.
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Air-Fluid Brass Pipe Thread Fittings

Cixi Air-Fluid Brass Pipe Fittings with Nickel-Plated ,Max. pressure: 1200 psi, except Domestic Brass fittings Temp. range: -65° to 250°F,NPT connections. For use in water, oil, natural gas, and steam applications.


The Configurations as below:

Brass Pipe Hex Nipple,Brass Pipe Nipple,Male Pipe to Female Pipe Hex Bushing,Brass Female Pipe Coupling,Reducer Bushing ,Countersink Plug,Brass Female Pipe Tee,Brass Male Pipe Tee ,Brass Male Pipe to Female Pipe Elbow,Brass Male Pipe to Male Pipe Elbow,Brass MNPT Reducing Bushing,Reducer Bushing,Bushing,Brass Pipe Female Elbow 90 Degrees,Reducing Adapter,Male Elbow, 90 Degrees,Brass MNPT x FNPT Reducing Bushing,Brass MNPT x FNPT Street Elbow, 90 Degrees,Brass Female Pipe Tee.

Brass Pipe Thread Fittings

Brass Pipe Thread Fittings, Brass Pipe Fittings, Threaded Pipe Fittings

Ningbo Air-Fluid Pneumatic Components Co., Ltd , http://www.air-fittings.com