1. Pipeline sewage pump to ensure the quality of parts
Pipeline sewage pump mechanical seal must be done before the factory seal performance test, and there is a certificate. Mechanical seal after long term operation, the moving ring and the static ring wear, spring shaft and corrosion wear, a sealing rubber ring wear, aging, deformation etc., can cause seal leaks must be repaired or replaced with new parts. Moving ring and a static ring sealing surface shall not crack, off angle, scratches, pits, flash and eccentric wear and scratches, pits can not through the seal. When the fixed ring is used, the height of the convex platform of the dynamic ring is not less than 3mm, and the height of a single boss is not less than LMM, so as to avoid the influence of the heat radiation. Dynamic ring should be installed after the guarantee can flexibly move on the shaft, the dynamic ring pressure to spring should be able to free bounce, keep dynamic and static ring perpendicular and parallel. Dynamic and static ring sealing gasket specifications conform to the drawing surface shall not be damaged, thickness and hardness uneven phenomenon, in the overhaul to replace the sealing ring. No rust cleaning of the outer surface of the spring, before use should shape length detection and pressure test, each spring in a specified compression length of pressure difference should meet the requirements, each spring in a specified compression length error of pressure to meet the requirements. Free length permissible error does not exceed 0.5 mm, compressed volume cannot be too little greater than, requirements of error of plus or minus 2mm. The sealing sleeve and the pump shaft are not using the same material, on both sides of face parallelism allows difference and with the axis not verticality allows difference does not exceed + 0.20mm.
2. The pipeline sewage pump to ensure adequate cooling and lubrication
Adjust the cooling pipe to adjust the valve opening, to ensure that the mechanical seal cooling pipe is unobstructed, the tank water pump to open the evacuation valve to exhaust the seal cavity gas.
3. Pipeline sewage pump to ensure the installation accuracy
Disassembly pump mechanical seal, dynamic and static ring must be cleaned up and in friction negative smear a small amount of clean oil to both high end and low end, bump is strictly prohibited. Until the static ring gland installation force should be uniform, to prevent partial pressure, check with feeler gauge, up, down, left and right position deviation less than 0.05mm; check the gland and outer diameter of shaft with the gap around to evenly, the allowable deviation of not more than 0.1ram. mounted pump mechanical sealing parts of the pump shaft radial runout of not more than 0.05mm. The pump cover and a sealing end cover, it is necessary to carefully review the mechanical seal installation location dimension, if the location size does not meet the requirements, in the shaft sleeve with the steel pad adjustment, but steel pad accuracy is higher and the difference of the thickness is not more than 0.01mm. Measurement of mechanical sealing sleeve radial runout and sealing surface of the end face runout conforms to the requirement.
Machine running on the seal, where a loosening of the packing gland sealing surface move, dynamic and static ring parts must be replaced, absolutely should not be re tightened continue to use. Because in this loose, the friction pair of the original motion trajectory will change, the sealing performance of the contact surface is very easy to be destroyed.
4. The pipeline sewage pump to adjust the end face pressure
The end face specific pressure is an important parameter in relation to the sealing performance and service life, which is related to the structure type, the spring size and the medium pressure. Face than the pressure than the general plus bad friction pairs, than the pressure is too small, it is easy to leak, often by the manufacturers to give a suitable range, end face than the pressure generally take 3 ~ 6kg/cm2. adjust the pressure is to adjust the compression spring. Free length of the spring with A said, the spring stiffness of the unit when the compression load to bear the K, the provisions of the requirements of the pressure with P said, these are manufacturers of a given parameter. Compressed size with B, then P/A-13=k, 13=A-e/k, this is the size of the spring after the installation of compression. If the spring after the installation size is too large, in a spring seat, an increase in the thickness of the adjusting pad with spring, the size is reduced by adjusting the thickness and the thickness of the adjusting pad with micrometer measuring take.
