GIS Bolt Tightening Torque Standards by Material & Size

GIS (Gas-Insulated Metal-Enclosed Switchgear) contains numerous bolted and screwed connections, and the tightening torque varies depending on bolt material, size, and application. The recommended tightening torque values are listed below for reference:

Table 1 Tightening Torque Values for Bolts of Different Materials and Sizes (N·m / kgf·cm)

Note: For materials other than Q235, apply the specified torque values as indicated in the instruction manual, drawings, or inspection cards; if not specified, use the torque values for Q235.

Torque specifications for connections such as tank flanges to bushing insulators, conductors to insulator inserts, and conductor-to-conductor joints are provided in Table 2 below:

Table 2 Bolt Tightening Torque Management Values

The tightening torque for metal flange to metal flange, and metal flange to porcelain bushing, is shown in Table 3 below:

Table 3 Bolt Tightening Torque Management Values