Pressure Vessels for Refrigerating Apparatus
This industry standard JB/T4750—2003 replaces JB6917-1998 and provides instructions for design and assessment tests for safe performance of pressure vessels for refrigerating apparatus.
1. Scope
This standard applies to pressure vessels used in the installation and maintenance of closed systems and components in refrigerating and air conditioning equipment. Pressure vessels include evaporators, condensers and accumulators, as well as their associated valves, pipes, fittings, pumps and compressors. This standard also applies to pressure vessels used within the scope of this industry standard, including pressure vessels with a length of more than 10 mm, height of more than 8 mm, and a width of more than 8 mm and with a capacity of up to 700 L.
2. Term and Definition
2.1 Pressure Vessel: A pressure vessel is a device used to contain and control the pressure, volume, temperature and pressure of a medium.
2.2 Pressure Test: A pressure test is a procedure to verify the seal and strength of a pressure vessel.
2.3 Design Pressure: Design pressure is the difference between the pressure of the medium inside and outside the pressure vessel at which the pressure vessel design and fabrication is based.
3. Design
The design pressure of pressure vessels for refrigerating apparatus should not exceed 8 bar. The minimum capacity indicated by the manufacturer for the pressure vessel should be equal to or greater than the indicated value. The design should meet the requirements below:
3.1 Design calculations
The design calculations should consider all applicable loading conditions, including internal and external pressures, temperatures, material properties, welded and bolted joint strengths, impact of dynamic forces, and transient loading conditions.
3.2 Design drawings
The design drawings should include specifications for all components, including material specification, weld joint preparation and welding, pressure testing and other requirements.
3.3 Pressure testing
Pressure testing should be performed on each pressure vessel, as specified in this standard.
4. Materials
The pressure vessels should be designed, fabricated and tested with materials that are suitable for the application and meet the requirements of this industry standard. Materials should meet any other conditions specified by the customer.
5. Fabrication
Fabrication of the pressure vessels should include any instructions and drawings provided by the manufacturer. The manufacturer should provide the necessary instructions for any processes such as welding and assembly.
6. Pressure Testing
The pressure vessel should be pressure tested prior to shipment as specified in this industry standard. The pressure test should be held at no less than 1.5 times the test pressure.
7. Marking
The pressure vessel should be marked with the manufacturers information, including the following: manufacturers name, model number and serial number. The pressure vessel should also be marked with any other information specified in this industry standard.
8. Inspection and Testing
Inspection and testing of the pressure vessel should include verification of the design, a visual inspection, and a pressure test prior to shipment as specified in this industry standard.
9. Documentation
The manufacturer of the pressure vessel should provide a report containing all relevant information, including the type and size of the vessel, the materials used, the test pressure and results, and the design calculations.
10. Summary
This industry standard JB/T4750—2003 provides instructions for designing, fabricating, and testing pressure vessels for refrigerating apparatus. The pressure vessels should be designed and tested to meet the conditions specified in this industry standard, and any additional conditions specified by the customer. The design should be verified through design calculations, fabrication should include all instructions provided by the manufacturer, and the pressure vessels should be tested prior to shipment as specified in this industry standard. The manufacturer should also provide a detailed report including all relevant information pertaining to the pressure vessel.
