Disc springs - Live Loading are an effective solution to leaks in flange joints caused by insufficient preload of the bolts, when the specific pressure on the seal decreases and thus possible leaks occur.
Insufficient preload of the bolts is the cause of 50 - 80% of leaks in the flange connections!
Due to rapid and significant changes in operating temperatures, there may be an increase and consequent decrease in the tension in the bolts, ie an increase and decrease in the specific pressure on the seal. These sudden pressure changes can result in additional deformation of the seal , which is no longer optimally compressed after the temperatures have stabilized, and can thus lead to leaks.
Disc springs are an effective solution because they are able to increase the elasticity of the screw connection .
Properly designed disc springs are able to increase the elasticity of the screw connection 7 - 15 times! Experience from refineries and petrochemical companies confirms that the use of disc springs on critical joints has been shown to increase their tightness .
Flanges suitable for the use of disc springs
- Critical flange connections where fluid leakage can cause an accident.
- Flange connections with large temperature changes.
- It is assumed that the bolts or seals of the flange joint will relax under operating conditions.
- Repeated leak problems.
- Loosening screws by vibration.
Pokorný designs and supplies disc spring sets for critical flange joints.