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The main manufacturing process of pressure vessel

A closed vessel that can withstand pressure is a pressure vessel. The pressure vessel has a very wide range of uses, and it has a very important position and function in many fields such as industry, civilian use, and military industry. Among them, it is more widely used in the chemical industry and the petrochemical industry. Pressure vessels used in the petrochemical industry alone account for about 50% of the total number of pressure vessels. In the chemical and petrochemical industries, pressure vessels are mainly used for heat transfer, mass transfer, reaction and other processes, as well as the storage and transportation of pressurized gas or liquefied gas. It is also used in other industrial and civil fields, such as air compressors. All kinds of special compressors of refrigeration compressors and auxiliary machines (coolers, buffers, oil-water separators, gas storage tanks, evaporators, liquid coolant storage tanks, etc.) are all pressure vessels.

1. Pressure vessel manufacturing process
Raw material preparation, marking, blanking, bending, forming, edge processing, assembly, welding, inspection, etc.

2.pressure vessel raw material preparation
Before marking the steel, the steel must be pre-treated. The pretreatment of steel refers to the purification treatment, correction and protective primer coating of steel plates, pipes and sections.

Before scribing, cutting, and welding the steel plates and pipes and after cutting, beveling, forming, and welding, as well as removing the rust, oxide scale, oil and welding slag on the surface of the steel, it is the purification treatment.

The process of correcting steel deformation caused by steel during transportation, hoisting or storage is orthopedic.

Protective paint is mainly used to improve the corrosion resistance of steel, prevent oxidation, extend the service life of parts and equipment, and apply a layer of protective paint on the surface.

Scribing is the first step in the manufacturing process of pressure vessels. It directly determines the dimensional accuracy and geometric accuracy of the parts after forming, and has a great influence on the subsequent assembly and welding processes.

Draw the blanking line processing line on the raw material or the preliminary processed blank. Various position lines and inspection lines are scribe lines, and the necessary signs and symbols are marked (or written down). The marking process usually includes unfolding, lofting and marking of parts. The size of the blank should be determined before dicing. The size of the blank is composed of the expanded size of the part and various machining allowances. The following are the methods to determine the unfolded size of the part:

1. Drawing method: refers to the use of geometric drawing method to expand the part into a plane figure.
2. Calculation method: refers to the calculation formula based on the principle of expansion or the principle of constant area before and after compression (tension) deformation.
3. Test method: It is simple and convenient to determine the unfolded size of the blank of the more complicated shape part through the test formula.
4. Comprehensive method: For overly complex parts, drawings and calculation methods can be used to determine the blank expansion size of different parts, and sometimes it can be verified by experimental methods.

Parts used to make containers can be divided into two categories: expandable parts and non-expandable parts. For example, a circular body and an ellipse are expandable and non-expandable parts, respectively.
 

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