Garlock Full Face Torque Qualification Statement
In some instances Garlock's recommended seating stress is not achievable. This is not to say the gaskets will not perform satisfactorily. Full face Gaskets normally have twice the number of square inches compared to ring gaskets. The extra material requires added torque which, again may not be obtainable in your application. However, if each flange face is flat and the gasket selected is made from a soft material, a full face gasket may work satisfactorily and may be desirable to prevent flange rotation.
These bolt torque tables are only to be used as a general guide. They should not be considered to contain absolute values due to the large number of uncontrollable variables involved with bolted joints.
All bolt torque values are based upon the use of new nuts and bolts of acceptable quality and that a non-metallic based lubricant (i.e. oil and graphite) be used on the nuts, bolts and washers.
The flanges are assumed to be in good condition. Special attention with respect to seating surface finish and flatness should be given.
Only torque wrenches that have been calibrated shall be used. The proper bolting tightening pattern should be utilized with the desired ultimate torque value arrived at in a minimum of three even increments. All bolts in the flange should then be checked in a counter-clockwise direction.
No provisions have been made for in these tables to account for vibration effects on the bolts. These tables are not compensated for elevated temperatures but are based on ambient conditions. If conditions different from these exist Garlock recommends that further analysis be performed to determine the proper solution.
These tables were developed to be used with Garlock's Compressed Non-Asbestos materials such as Blue-GardŽ Styles, HTC 9800, 9850, 9900, St-706 and others.