This standard specifies the structural type, basic dimension, performance, test requirements, marking and etc. of steel O-ring face seal fittings with tube outside diameter of 6~50mm.
This standard is applicable to the connection with O-ring face seal fittings with working medium of hydraulic oil (solution), working temperature range of -20~+100℃ and pressure from 6.5kPa absolute vacuum pressure to the working pressure listed in Table 11.
2 Normative References
The following normative documents contain provisions which, through reference in this text, constitute provisions of this standard. For dated references, subsequent amendments to (excluding amending errors in the text), or revisions of, any of these publications do not apply. However, all parties coming to an agreement according to this standard are encouraged to study whether the latest edition of the normative document is applicable. For undated references, the latest edition of the normative document applies.
GB/T 3 Run-outs, Undercuts and Chamfers for General Purpose Metric Screw Threads (GB/T 3-1997, eqv ISO 3508: 1976, ISO 4755: 1983)
GB/T 196 General Purpose Metric Screw Threads - Basic Dimensions (GB/T 196-2003, ISO 724: 1993, MOD)
GB/T 197 General Purpose Metric Screw Threads-Tolerances (GB/T 197-2003, ISO 965-1: 1998, MOD)
GB/T 230.1 Metallic Rockwell Hardness Test - Part 1: Test Method (Scales A, B, C, D, E, F, G, H, K, N, T) (GB/T230.1-2004, ISO 6508-1: 1999, MOD)
GB/T 699 Quality Carbon Structural Steels
GB/T 905-1994 Dimension, Shape, Weight and Tolerance for Cold-drawn Round, Square and Hexagonal Steels (neq ISO 286-1: 1988)
GB/T 1184-1996 Geometrical Tolerancing - Geometrical Tolerance for Features without Individual Tolerance Indications (neq ISO 2768-2:1989)
GB/T 1220 Stainless Steel Bars
GB/T 1804-2000 General Tolerances - Tolerances for Linear and Angular Dimensions without Individual Tolerance Indications (neq ISO 2768-1: 1989)
GB/T 3141 Industrial Liquid Lubricants - ISO Viscosity Classification (GB/T 3141-1994, eqv ISO 3448: 1992)
GB/T 3452.1-1992 Fluid Systems - Sealing Devices - O-rings - Inside Diameters, Cross-sections, Tolerances and Size Identification Code (neq ISO 3601-1: 1988)
GB/T 3639 Seamless Cold-drawn or Cold-rolled Steel Tubes for Precision Applications (neq DIN 2391/1-1994, DIN 2391/2-1994)
GB/T 5231 Wrought Copper and Copper Alloys Chemical Composition Limits and Forms of Wrought Products
GB/T 5568 Rubber or Plastics Hoses and Hose Assemblies - Hydraulic-pressure Impulse Test without Flexing (GB/T 5568-1994, neq ISO/DIS 6803: 1991)
GB/T 6031 Rubber, Vulcanized or Thermoplastic - Determination of Hardness (Hardness between 10IRHD and 100IRHD) (GB/T 6031-1998, idt ISO 48: 1994)
GB/T 10125 Corrosion Tests in Artificial Atmospheres - Salt Spray Test (eqv ISO 9217: 1990)
GB/T 17446-1998 Fluid Power Systems and Components - Vocabulary (idt ISO 5598: 1985)
ISO 6149-2 Connections for Hydraulic Fluid Power and General Use - Ports and Stud Ends with ISO 261 Metric Threads and O-ring Sealing - Part 2: Dimensions, Design, Test methods and Requirements for Heavy-duty (S series) Stud Ends
3 Terms and Definitions
For the purpose of this standard, the terms and definitions established in GB/T 17446as well as those listed below apply.
3.1
Fluid power
The mode or method where energy is conversed, transmitted, controlled and distributed by using a pressurized fluid as the medium, which is referred to as hydraulic and pneumatic for short.
3.2
Working pressure
The pressure at which the device operates.
3.3
Connection; fitting
The leak-proof device to connect pipeline to one other, or to component.
3.4
Fitting body
The part exerting the main connection function in a fitting. A fitting body may be a fitting or part of a fitting.
3.5
Assembly torque
The torque applied to obtain satisfactory assembly.
3.6
Adjustable stud end
The stud end connection fitting that allows for fitting direction adjustment before tightening of the nut to complete the connection. Generally, this type of stud end is only used on fittings such as tees, crosses and elbows.
3.7
Non-adjustable stud end
The stud end connection fitting that does not require specific direction adjustment before tightening. It is only used on straight fittings.
