The sealing performance of fire pumps is one of the key factors in measuring the quality of fire pumps. So, how to control the tightness of the fire pump?
What are the requirements for inspection of the seal?
The surface of the auxiliary sealing ring is smooth and flat, and there are no defects such as bubbles, cracks, and notches; the size of the end surface should be uniform; the burr of the O-ring is at an angle of 45 degrees to the working surface.
Once the seal ring shows bubbles, cracks, etc., the seal is leaking. For this reason, in the daily operation of the fire pump, it is necessary to carry out irregular inspections, and once found, replace or repair them immediately.
The hardness of the auxiliary sealing ring should be selected according to the pressure, the sealing pressure is higher, the hardness is higher, and the sealing pressure is lower, the hardness is lower. Generally speaking, when the fire pump is manufactured, the professional manufacturer will have a standard, and the effective design will be based on the actual model, use and pressure of the fire pump to select the appropriate hardness. For example, the auxiliary sealing ring is generally made of synthetic rubber material.
The compression amount of the auxiliary sealing ring should be suitable, the compression amount is too large, the sealing effect is good, but the friction resistance is large, the assembly is difficult, and the swimming compensation ability is poor during work. The amount of compression is too small, the frictional resistance is small, the assembly is easy but the sealing effect is poor; The compression of the auxiliary sealing ring should take into account its other functions, such as the static ring without anti-rotation pin. The static ring O-ring seal plays the dual role of sealing and anti-rotation. The compression of the sealing ring is larger to avoid the static ring. Rotate, the seal fails. The O-ring seal of the moving ring, under the premise of ensuring the sealing effect, the compression amount is smaller, thereby preventing the compression amount from being too large, and the resistance is too large to be float-compensated.