SU564452A1 - Method for determining sealing of oil cylinder - Google Patents

Description

one

The invention relates to a method for the control and testing of equipment, in particular, equipment.

Devices are known for testing the equipment of hydraulic and pneumatic automation devices that measure pressure drops in equipment tanks for a certain time 1.

The closest to the technical essence of the invention is a method for determining the tightness of a hydraulic cylinder, which involves loading the hydraulic cylinder rod with a constant external force in measuring one of the tightness parameters, for example, the pressure in the hydraulic cylinder 2.

However, the known methods of testing it is impossible to determine the degree of tightness with micro leakage of liquid in case of obliteration of gaps.

The aim of the invention is to improve the accuracy of leak detection.

According to the proposed method for determining the tightness of a hydraulic cylinder, simultaneously with measuring the pressure in the hydraulic cylinder, it is measured; and another tightness parameter

for example, the position of the piston of the hydraulic cylinder, abruptly changes the magnitude of the external force and restores it to a value at which one of the tightness parameters takes the initial value, after which the current tightness parameter is measured.

FIG. 1 shows the hydraulic circuit of the stand for determining the tightness of the hydrocyliner in FIG. 2 is a graph of the load on the rod of the hydraulic cylinder being tested (leak tightness in this case is the pressure in the hydraulic cylinder and the position of its gap).

The stand includes a rigid frame 1, a test cylinder 2 with a rod 3, a piston 4 and a sealing unit 5, a load cylinder 6 connected by hydraulic lines to the distributor 7. The stand is serviced by a pump 8. The hydraulic system contains valves 9-12.

Claims (2)

Test 2 and loading 6 hydraulic cylinders are mounted on frame 1 so that direct force interaction is carried out. Then, using the distributor 7, the liquid or pump 8 is directed into the crank chamber of the cylinder 6. The pressure is set by the safety valve Yu, so that the rod 3 of the cylinder 2 is loaded with a constant external force (Fig. 2). This measures the pressure in the piston cavity of the test rack and the position of the piston (rod) h, -. relative to the cylinder. Then, the switching of the distributor 1 causes the fluid to be supplied to the piston cavity of the cylinder 6, so that the pressure in it is controlled by the safety valve 11 and the load changes abruptly — it decreases by 5 0-6% to (Fig. 2). After exposure 2-5 seconds. The external forces are restored to Vi, i.e., to the initial pressure, and the position of the piston (rod) h / j relative to the cylinder is measured. The case hj means that the piston has sunk relative to the original one, or Ha. which indicates the leakage of fluid from the cylinder, i.e. presence of leakage. If, after an abrupt change in load, the piston takes the initial position h N dZloklyuchena hydro system is sealed. On such a bench, it is possible to determine the tightness by another method, which leads to the fact that, after loading the rod with a constant external force T, the pressure in the cavity of the hydraulic cylinder 2 and the position of the piston h, j are measured, and then after the jump -. figuratively changing the external force to 2 (as indicated above) by the cylinder 6, restore the initial position of the piston h; and measure the pressure in the cylinder cavity 2. If there is a leak, the pressure in the closed volume drops. If the pressure in the hydraulic cylinder does not change relative to the original, the closed system is tight. Depending on the degree of leakage of the test cylinder, the indicated loading cycles can be repeated many times. In this case, pressure and displacement measurements should be made only in the initial load after the last cycle. Claim Method A method for determining the tightness of a hydraulic cylinder, consisting in loading a hydraulic cylinder rod with a constant external force and measuring one of the tightness parameters, such as pressure in a hydraulic cylinder, characterized in that, in order to improve the speed and accuracy of determining tightness, simultaneously with measuring pressure in a fluid generator. Another parameter of leaktightness is measured at the cylinder, for example, the position of the piston of the hydraulic cylinder, change the velocity of the external force in a jump-like manner and restore it to or in which one of the leak takes Ini- tially value, whereupon the other measured parameter tightness. Sources of information taken into account in the examination: 1. The patent of Poland № 56455, кп. 42 K 30/03, 1968. 2 Sat. Hydraulic drive and hydropneumatic automation, Kiev, Technique, 1976. p. 57.