GB/T 5648-2008Flared couplings - Style B nut (English PDF)

Foreword

This standard is one flared fittings series. This standard is GB/T 5648-1985 "flared type tube fittings B" amendments. The main amendments are.

--- Modified Chinese and English name;

--- Increased 14, 16 and 18 three specifications;

--- Reducing the parameters should be part of the manufacturer's control;

--- Tolerance on the part of prevailing standards of tolerance and fit adjustment;

--- Cancel the marked surface roughness, roughness conditions are given in the technical standards. Since the implementation of this standard replaces GB/T 5648-1985. The standard proposed by China Machinery Industry Federation. This standard by the National Standardization Technical Committee pipe accessories. This standard is drafted by: Productivity Promotion Center in the machine. Participated in the drafting of this standard. Haiyan Pipe Manufacturing Co., Eaton (Ningbo) fluid connector Ltd., Jiaxing Mai Site fittings Manufacturing Co., Ltd., Jianhu particularly good hydraulic pipe fittings Co., high-Bo Haiyan Pipe Co., Ltd., Haiyan tube Manufacturing Co., Hydraulic annex Ltd. Jiaozuo City lead. The main drafters of this standard. Li Weirong, Gengzhi school, Zhou Shunhua, Li Junying, Tao Zhongming, Zuo Jun, Ruanhao Feng, Zhou Jianfei, Wang Limin, Feng Feng. This standard replaces the standards previously issued as follows:

--- GB/T 5648-1985. Flared type tube fittings B nuts

1 Scope

China's national standard for the style B nut used in flared tube couplings. Style B is the second nut form of the family, and the reason for having two is practical rather than arbitrary. The nuts differ in their hexagon size and body proportions for a given tube, so one form suits installations where fittings sit close together and a large hexagon would foul its neighbour, while the other gives a better grip where access is free. Since a flared joint is tightened to a torque that must actually reach the flare, whether a spanner can be got onto the nut and swung is not a detail: an under-tightened flare leaks and an over-tightened one is crushed, and both failures trace back to how the nut could be reached. The two styles are not interchangeable within one joint. The standard specifies the style B nut's dimensions and technical requirements, for tube outside diameters of 4 to 34 mm at working pressures of 3.5 to 16 MPa.

This standard specifies the flare tube fittings B nut size and technical requirements. This standard applies to pipe outside diameter 4mm ~ 34mm, the maximum working pressure of the hydraulic fluid and transmission of a 3.5MPa ~ 16MPa General purpose piping system.

2 Normative references

The following documents contain provisions which, through reference in this standard and become the standard terms. For dated references, subsequent Amendments (not including errata content) or revisions do not apply to this standard, however, encourage the parties to the agreement are based on research Whether the latest versions of these documents. For undated reference documents, the latest versions apply to this standard.

GB/T 5653-2008 flared tube fittings

3 Dimensions

Flared type tube fittings B-type nut dimensions shall comply with the provisions of Figure 1 and Table 1.

4 Mark

4.1 labeling method Flared type tube fittings marked B nuts shall comply with GB/T 5653's.

4.2 tag example Tube outer diameter of 10mm, steel flared fittings are zinc coated with a type B nut marked. Nut GB/T 5648 B10

5 Technical requirements

Technical requirements according to GB/T 5653 regulations.