GB/T 17186.2-2018Calculation methods for the pipe flange joints - Part 2: Calculation method satisfies leakage rate (English PDF)

3.1 Integral flange

The flange can be connected to the shell by welding (e.g., welding neck flange, see Figures 4~7;

or slip-on flange, see Figures 8 and 11) or by casting (integral cast flange, type 21).

3.2 Blank flange

For protective cover, see Figure 9.

3.3 Loose flange

A back-up ring that is connected to the collar.

3.4 Hub

The axial extension of the flange ring is typically used to connect the flange ring to the shell, as shown in Figures 4 and 5.

3.5 Collar

The portion adjacent to the loose flange, as shown in Figure 10.

3.6 External load

Forces and/or moments that other external loads acting on the joint, such as the weight of the pipe and thermal expansion.

3.7 Load condition

A set of conditions in which loads are applied simultaneously, as denoted by I.

3.8 Assembly condition

The initial load condition for tightening the bolts, as denoted by I = 0.

3.9 Subsequent condition

Load condition after assembly condition, such as test conditions operating condition, and various conditions during start-up or shutdown, as denoted by I = 1, 2, 3,...

3.10 Compliances; Y

The reciprocal of stiffness (axial).

NOTE. Unit is in mm/N.

3.11 Flexibility modulus

The reciprocal of the stiffness modulus, excluding the material's elastic constant.

The axial flexibility modulus is denoted by X, in 1/mm; the gyratory flexibility modulus is denoted by Z, in 1/mm³.

4.1 Illustrations

Figures 1~12 show the symbols related to geometric parameters. Figures 1~12 are schematic diagrams only and do not list all flange types applicable to this calculation method.

GB/T 17186.1-2015 | GB/T 17185-2012 | GB/T 17241.6-2008 | GB/T 19285-2026 | […]