Novel mechanical sealing performance testing apparatus

Abstract

The invention discloses a novel mechanical sealing performance testing apparatus which is characterized in that a main shaft penetrates through a left end cover and a right end cover on a sealing cavity shell; two pairs of measured sealing rings with the same size are arranged on main shafts at the left end and the right end in the sealing cavity shell; no additional axial force generates at any test medium pressure; two sections of threads of which screw pitches are same and the spiral line directions are opposite are machined on a long shaft sleeve which is in clearance fit with the main shaft; the long shaft sleeve is clockwise rotated to drive a left nut and a right nut which are screwed with the long shaft sleeve to equidistantly move leftwards and rightwards; and a left pressure spring and a right pressure ring are pushed to respectively press two moving rings, so that specific pressures borne by a left pair of sealing surfaces and a right pair of sealing surfaces are identical. The two pairs of sealing rings with the same size are adopted for testing; an average value of test results of the sealing rings is used as a test torque and leakage rate of mechanical sealing of the model number, and thus the influence on the accuracy of the torque and the leakage rate caused by accidental factors such as mounting when only one pair of sealing rings are used for testing is reduced.

Description

1. Technical Field [0001] The invention belongs to the technical field of mechanical seal testing, and particularly relates to a novel mechanical seal performance test device with no additional axial force and two seal end faces with equal specific pressure adjustment. 2. Technical background [0002] As the shaft seal of the power input shaft of pumps, compressors and agitators, mechanical seals are widely used in petrochemical, electric power, aviation and other fields. With the continuous progress of material science and manufacturing technology, the life and reliability of mechanical seals have been greatly improved, but in industrial applications, their failures are still common. In order to obtain a mechanical seal with long life and stable performance, it is not only necessary to further optimize and design the mechanical seal structure on the basis of previous studies, but also to develop a reliable and convenient mechanical seal performance test device. [0003] According...

AI Technical Summary

Problems solved by technology

For the single cantilever shaft mechanical seal test device, the power input shaft penetrates into one end cover of the seal cavity, such as figure 1 As shown, the measured mechanical seal is used as the seal of the chamber, which is similar to the scene, but the seal shaft end is in the seal chamber, and the shaft end is subjected to the action of medium pressure to generate axial force, and the medium acting area on both sides of the seal is not equal. , will also generate axial force, and the bearing resistance torque caused by different axial forces is different, which affects the measurement accuracy of end face friction torque; for the double cantilever mechanical seal test device, such as figure 2 As shown, the axial force caused by the medium pressure on a single shaft end and the axial force caused by the unequal medium action area on both sides of the seal will be balanced by its symmetrical structure, but the length of the device is increased, especially the increased The complexity of the connection structure between the power input shaft and the power device; for the single cantilever mechanical seal test device, the power input shaft is used to penetrate through the end covers on both sides of the seal chamber, and the two pairs of seal pairs are symmetrically arranged in the seal chamber. On the seal chamber end cap, such as image 3 shown

If the dimensions and specifications of the two pairs of seal pairs at both ends are inconsistent, the axial force caused by the medium pressure will not be balanced; even if the dimensions and specifications of the seal pairs at both ends are the same, due to structural limitations, the spring force at both ends will not be adjusted after installation, that is During the test, the two pairs of tested sealing surfaces could not realize equal pressure adjustment

Images