The heating of the hydraulic system of the stainless steel gear pump directly affects the normal operation of the stainless steel gear pump. The harm caused by the heating phenomenon mainly includes the following situations:
(1) when the temperature of the working liquid increases, the viscosity of the working liquid decreases, the leakage of the pump increases, and the actual flow rate of the pump decreases.
(2) the seals of hydraulic systems and components deteriorate at high temperature, the elastic denaturation ability decreases, the sealing performance decreases, even the seal fails, and the leakage increases.
(3) when the spool and body materials of the hydraulic valve are different and the coefficient of thermal expansion is different, the spool is stuck between the spool and the body due to thermal expansion, so that the stainless steel gear pump cannot work.
(4) when the viscosity of the working liquid decreases, the lubrication performance of the working liquid is reduced, the wear of the hydraulic components is accelerated, the wear failure of the components is accelerated, and the service life of the components is shortened.
In order to avoid the above phenomena as far as possible, some stainless steel gear pumps have to stop after using for a certain period of time to cool the system, thus reducing the operating rate of stainless steel gear pumps and affecting the construction progress. Therefore, in view of the heating cause of the system, corresponding measures should be taken to control the temperature of the hydraulic system to ensure the normal use of the stainless steel gear pump.
The common gears of stainless steel gear pump are straight tooth, helical tooth, herringbone tooth and spiral tooth, and the tooth profile mainly has involute and arc type. Generally, involute spur gears are usually used in small gear pumps, modified gears are often used in high temperature gear pumps, and involute helical gears are often used in melt pumps that transport high viscosity and high pressure polymer melt. The rigidity and reliability of the gear and shaft are higher than those of the gear pump manufactured separately. The gears of foreign low-pressure gear pumps often adopt square structure, that is, the tooth width of the gear is equal to the diameter of the tooth tip circle. The tooth width of the high viscosity gear pump used in high pressure is less than its tooth tip circle diameter, which is to reduce the radial compression area of the gear and reduce the load of the gear and bearing. Stainless steel gear pump is a new type of liquid conveying machine, which has the advantages of simple structure, safe and reliable operation, convenient use and maintenance, continuous and uniform liquid discharge, stable pressure and so on.
