It is a method to eliminate leakage by adjusting the operation, adjusting the pre-tightening force of the seal or adjusting the relative position between the parts. It can be divided into fastening method, position adjustment method, flushing method, upper sealing method, operation method, starting method, etc.
(1) The tightening method is a method of applying a certain pre-tightening force to the leaking seal to prevent leakage. This method is suitable for gaskets, packing, opening and closing parts.
① During the heating process of petrochemical industry, power generation station and other units, the gaskets on the equipment and valves will leak. Depending on the situation, the bolts need to be tightened 1 to 3 times to eliminate the leakage. Due to the improper installation of the gasket, there are defects such as eccentric openings, which cause the gasket to leak. At this time, the bolts should be tightened from the leak, and then the bolts should be tightened symmetrically from both sides one by one to stop the leakage. If the flange is too large and the above method does not work, loosen the bolts at the smallest flange clearance and then tighten the flange at the largest flange clearance to eliminate leakage.
②During operation, the packing leaks, and the gland nut has a certain pre-tightening clearance. Tighten the gland bolt symmetrically or tighten the gland nut to stop the leakage.
③When the valve leaks due to vibration, wear, temperature change, etc., external force can be used to apply a large torque to the handwheel to forcibly close the gate or valve disc to stop the leakage. When the plug body of the plug valve and the taper hole in the valve body leak due to poor sealing, properly loosen the adjusting screw, tighten the nut or press the packing to force the tap body and the taper hole in the valve body to be tight.
