The required tightening torque of the bolts

The torque is called the force of rotation, that is, the tightening of the nut. The force of rotation is measured in Newtons by 1 meter - Nm. For flanges that have bolted fasteners, the torque produces an axial load on them. Axial load (axial) is the force that acts on the edge of the filter element. It can lead to deformation of the element or leakage. At the moment of tightening the bolts, the effect of the spring is observed.

When tightening the nut, the tension of the bolt occurs, the load on the gasket becomes stronger. The axial load is in direct proportion to the frictional force. If it changes, then certainly there will be a change in the load that the gasket experiences. To tighten bolts according to all rules, they must be lubricated together with nuts and washers. The thrust in the assembly of the flanges influences and influences the axial load and is important. Torque here is attached with a special torque wrench. True, there are more precise methods that affect the tightening torque of bolts and the final result.

What should be the effort at connecting the bolts?

The bolt clamps the flanges together. At the moment of tightening the bolts, they must be tightened to maintain the load on the gasket and at temperature differences, and pressure drops in the normal working process, and when the system is pressurized.

The auxiliary load acts on the connection in a certain way. Then the bolted joint is able to adapt under any conditions and remain thus tight.

The yield strength of the material from which the bolt is made is the load that allows it to be stretched to the maximum allowable length, after which it returns to its original state. Stretching may be above the permissible yield strength. In this case, when the load is removed, the bolt serves as a kind of "return spring".

When the tightening torque of bolts is exceeded, the permissible yield strength value is stretched, which leads to a reduction in the load. When tightening the bolt, care must be taken so that no constriction occurs, which will definitely lead to spoilage. The tightening torques of bolts are a painstaking process, you need to ensure that the overall load on the gasket weakens gradually, at a scale of 40-100% of the yield point. It must also be ensured that the integrity of the gasket and flanges does not change. The voltage that can be applied to the surface of the gasket should never exceed a predetermined value. A suitable choice of bolt is an indispensable condition for the work of connecting the flanges.

How to maintain tightness?

Two conditions that must be met:

1. Effort to break the gasket and hold it in place. The bolt load must be such that the gasket is compressed along the surface of the flange.
2. Effort needed:

• For hydrostatic loading.
• The gasket is pressed and held steady so that the pressure does not get inside.
• Save the load on the gasket after the hydrostatic load is removed.