1. Stainless steel pressure pipe installation qualification and quality assurance system

Stainless steel pressure pipe installation is a major link to ensure the safety of pressure pipes. The installation quality of stainless steel pressure pipes directly affects the safe use of pressure pipes. To this end, the state implements a license system for the installation of stainless steel pressure pipes. The pressure pipe installation unit must hold a pressure pipe installation permit issued by the quality and technical supervision administrative department. The assessment of the qualification approval of the pressure pipe installation unit shall be carried out by an accreditation body approved by the quality and technical supervision administrative department. According to the particularity of the stainless steel pressure pipeline, the pressure pipeline installation unit must have the following conditions: the authorized organization of the legal person; the quality assurance system for the installation of the pressure pipeline; the technical strength required to adapt to the installation and management of the pressure pipeline; the intact production equipment that meets the requirements for on-site construction, Inspection means and pipeline prefabrication site; ability to install qualified products.

In order to ensure the quality of stainless steel pressure pipe processing, prefabrication and installation, the pressure pipe installation unit shall, in accordance with the requirements of relevant laws, regulations, codes and standards, and the actual conditions of the unit, refer to the provisions of GB/T 19000 - ISO 9000 series standards. Establish a sound quality assurance system for stainless steel pressure piping installation. The pressure pipeline installation quality assurance system shall be under the leadership of the corporate legal person, and shall be presided over by the chief technical officer of the enterprise (or the deputy chief of the technical department). According to the quality control requirements during the installation of the pressure pipeline, the installation unit shall set up the necessary quality control system in the quality assurance system (referred to as the quality control system. Each quality control system shall set up the necessary control links and control points, and each quality control system. There should be clear information transmission and feedback channels between control links and control points. Quality control should generally include: design quality control, procurement and material quality control, construction process quality control, intermediate quality control during construction, welding quality control, heat treatment. Quality control, inspection and test quality control, non-destructive testing quality control, physical and chemical and measurement quality control, equipment quality control, overall completion acceptance quality control, customer service, personnel training, etc.

Second, the construction process of stainless steel pressure pipe installation

The construction process of stainless steel pressure pipes generally includes construction preparation and on-site installation and commissioning. Construction preparation includes technical preparation, resource preparation and site preparation; on-site installation and commissioning include installation of hangers and hangers, on-site assembly and welding of piping components, piping system testing, purging and anti-corrosion insulation. Due to the different uses and structures of stainless steel pressure pipes, the specific construction procedures are also different. Most of the pipes of chemical enterprises belong to industrial pipes. Industrial pipes are generally used to connect various equipments in production equipment to transport process medium and compressed air, nitrogen and steam. For common system materials, in order to facilitate operation and maintenance, in addition to a small amount installed in the pipe trench, it is generally laid on the ground support structure. Its general construction procedure is shown in the figure. Buried pipelines are concealed projects. Because they are laid underground, they do not occupy the ground space, do not affect people's production and living activities, and are not sensitive to climate change. However, it is not easy to inspect and repair, and it is vulnerable to geological changes. Therefore, buried pipelines are mostly used in the case where the pipeline structure is relatively simple and does not require frequent operation and maintenance. In industrial pipelines, it is mainly used for non-toxic and non-combustible. Laying of utility piping. On-site installation of stainless steel pressure pipes is to assemble prefabricated pipe sections, finished valves, pipe fittings, fasteners, seals, supports and pipe ancillary equipment according to design requirements by welding, screwing or flange connection. The construction process of the complete pipeline system. According to the principle of civilized construction, first easy and difficult, the pressure pipeline should be laid on site in the following order: first underground, then on the ground, first large pipe, then small pipe; first clamp casing, then single pipe; first high pressure pipe, after medium, Low pressure pipe.