NB/T 47052-2016Simple pressure vessels (English PDF)

1.4 Vessel scope

1.4.2 Pressure-bearing heads, flat covers, fasteners of nozzles, hand holes, etc.

1.4.4 Non-pressure components directly connected to the vessel, such as supports, etc.

1.4.5 Overpressure relief device directly connected to the vessel.

1.4.3 Welded joints between non-pressure components and pressure components

1.4.1 Connection between vessel and external pipeline

a) The groove surface of the first circumferential joint of the welded connection;

b) The end face of the first threaded joint of the threaded connection;

c) The first flange sealing surface of the flange connection;

d) The first sealing surface of a special connector or pipe connection.

3.1 Terms and definitions

The terms and definitions as defined in GB 150.1, as well as the following terms and definitions, apply to this document.

3.1.1 Mechanized welding

Mechanized welding includes automatic welding and motorized welding. The automatic finger welding machine automatically adjusts and controls the process parameters and completes the welding; the motorized finger welder operates the welding machine to adjust and control the process parameters and completes the welding.

3.2 Symbols

C - Additional wall thickness, mm;

4.1 Product type

4.1.1 The vessel shall be a single-layer structure, consisting of a cylinder and a convex head (limited to oval, dish, spherical, excluding spherical cap) or flat cover through welding, OR two convex heads through welding.

4.1.2 The nominal wall thickness of the vessel cylinder and convex head shall not be greater than 10 mm; only a single cylinder section or no cylinder section, and no more than one longitudinal welding joint are allowed.

4.2 Product type code

The product type code is recommended to be in the form of Appendix B.

5.1 General provisions

In addition to complying with the provisions of this standard, the materials, design, manufacturing, inspection, acceptance of vessels must also comply with relevant laws, regulations, rules, and safety technical specifications promulgated by the state.

5.2 Qualifications and responsibilities

5.2.2.2 Responsibilities of the design organization.

5.2.2.3 Responsibilities of the manufacturer.

5.2.2.4 Responsibilities of inspection agencies

The institutions and their supervisory inspectors that conduct supervisory inspections of vessels, within the jurisdiction of TSG 21, shall perform corresponding work responsibilities, in accordance with the provisions of the specifications during supervisory inspections; they shall be responsible for the completeness and accuracy of the inspection reports issued.

5.3 General provisions for design

5.3.3 Additional thickness

The additional thickness C is determined according to formula (1).

5.3.3.1 Negative deviation of material thickness

The negative thickness deviation of plates or pipes shall be in accordance with the provisions of the corresponding material standards.

5.3.3.2 Corrosion allowance

In order to prevent the vessel from weakening and thinning due to corrosion and mechanical wear, a corrosion allowance shall be considered. The specific provisions are as follows. […]

5.5 Pressure resistance test

5.5.1 After the vessel is made, it shall subject to a pressure resistance test. The type, requirements, test pressure value of the test shall be indicated on the drawing.

5.5.2 Pressure resistance test pressure of vessel.

7.1 Design of wall thickness

7.1.1 Design of calculation method

7.1.1.1 The design pressure of the vessel shall not be lower than its working pressure.

7.1.2 Design of test method

7.1.2.1 The design organization shall conduct bursting tests on the physical samples of vessels, which are trial-produced by the client; it shall proceed according to the steps specified in 7.1.2.2.

7.1.2.3 Only when the requirements of item a) and b) of this article are met at the same time, can the sample be considered qualified for the bursting test.

7.1.2.4 Determine the design thickness deltad, based on the actual measured wall thickness of each main pressure component, as measured on the sample that passed the bursting test.

7.1.2.5 The design organization shall fully consider the repeatability of bursting test results, as well as the differences in mechanical properties between different batches of materials of the same steel designation.

7.1.2.2 Test steps

7.1.3 Marking of thickness

7.1.3.1 Calculation method for designed vessels.

7.2 Opening and opening reinforcement

7.2.1 In addition to the necessary process nozzle openings, the vessel can be equipped with inspection holes such as observation holes and hand holes, as needed. A drain outlet shall be provided at the lowest point at the bottom of the vessel.

7.2.2 The maximum allowable diameter of the opening on the vessel shell is dop <= Di/2.

Except for 7.2.3, all other provisions for openings and reinforcements shall comply with the corresponding chapters of GB 150.3.

7.2.3 All openings shall avoid butt welding joints. The distance -- between the edge of the weld at the opening and the edge of other welds -- shall not be less than 4 times the actual measured wall thickness of the opening and not less than 20 mm.

7.3 Welded structure

7.3.1 All main body welding joints must adopt full penetration type.

7.3.2 See Appendix C for commonly used welded joint structures.

7.4 Supports and supporting plates

8.1 General

8.1.1 Basis for manufacturing, inspection, acceptance

The manufacturing, inspection and acceptance of vessels shall comply with the provisions of this standard and the requirements of the design documents.

8.1.2 Type test

Vessels shall be type tested by a type testing agency, which has corresponding qualifications; type testing shall be in accordance with the provisions of 8.4.

8.1.3 Material substitution

The manufacturer shall obtain written approval, in advance from the original design organization when substituting materials for pressure components. Substitution of materials must be recorded in detail on the as-built drawings.

8.2 Manufacturing

8.2.1 Material re-inspection and sign transplantation

8.2.1.1 Reinspection of materials

8.2.2 Group batching

Vessels of the same model, drawing number, welding joint using the same welding process can be produced in batches. The requirements for group batching are as follows. […]

8.2.3 Forming and assembly

8.2.3.4.5 The main geometric dimensions and pipe opening orientation of the vessel shall be inspected and shall comply with the drawing requirements.

8.2.3.1 Forming

8.2.3.1.1 The manufacturer shall determine the processing allowance based on process conditions and the actual thickness of the steel, to ensure that the measured minimum forming thickness of the pressure components of the vessel is not less than the design thickness.

8.2.4 Welding

8.2.4.1 Preparation before welding and welding environment

8.2.4.1.1 The storage warehouses of welding rods, fluxes, other welding materials shall be kept dry; the relative humidity shall not be greater than 60%.

8.2.4.1.2 Before using welding materials, oil and rust must be removed from the welding wire; the protective gas shall be kept dry; the welding rod flux shall be re-dried according to the specifications specified in the product manual.

8.2.4.1.3 Welding shall be performed indoors. When any of the following conditions occurs in the welding environment and there are no effective protective measures, welding shall be prohibited.

8.2.4.1.4 When the temperature of the weldment is lower than 0 °C, preheating shall be performed at the starting point of welding.

8.2.4.2 Welding process

8.3.2 Sampling inspection and test

For vessels designed according to the test method, the manufacturer shall conduct bursting tests, on a batch basis during manufacturing; for vessels designed according to a calculation method, the manufacturer shall conduct radiographic testing on a batch basis.

8.3.2.1 Sampling

The inspection personnel of the manufacturer shall select test samples from the same batch of finished products, that have been assembled. The number of samples shall be as specified in 8.3.2.2 and 8.3.2.3. Sampling must ensure randomness and representativeness of the sample.

8.3.2.2 Bursting test

ENERGY INDUSTRY STANDARD OF THE PEOPLE'S REPUBLIC OF CHINA

ICS 23.020.30

J 74 Simple pressure vessels Issued on. AUGUST 16, 2016 Implemented on. DECEMBER 01, 2016 Issued by. National Energy Administration Announcement of National Energy Administration No.6, 2016 […]