A manhole cover positive and negative pressure performance test bench and method

Abstract

The invention discloses a manhole cover positive and negative pressure performance testing test bench and method. The test bench includes a frame, a test chamber is arranged in the center of the frame, a manhole cover is arranged on the upper part of the test chamber, and a semi-circular ring is arranged on the top of the manhole cover. Type pressure plate, two cylinders are symmetrically arranged on both sides of the frame, the piston rod of the cylinder is connected with the semi-circular symmetrical pressure plate, the air inlet, suction port and pressure sensor are set at the lower part of the test chamber, and the air inlet is passed through the two-position two-way electromagnetic The reversing valve one is connected to the air source, the suction port is connected to the vacuum pump through the two-position two-way electromagnetic reversing valve two, and the rodless chamber and the rod chamber of the cylinder are connected to the air source through the three-position four-way electromagnetic reversing valve; The method includes four steps of installation and compression of the manhole cover, test cavity inflation test, test cavity suction test, unloading and disassembly of the manhole cover. The invention makes up for many shortcomings of the existing manhole cover detection device and testing method, and realizes the integration of automatic compression, testing, unloading and disassembly steps in the test process of the positive and negative pressure performance of the manhole cover.

Description

technical field [0001] The invention relates to a test bench and method for positive and negative pressure performance testing of a manhole cover. Background technique [0002] The manhole cover is widely used on the oil tank of the oil tanker. Its unique structural design can ensure that the pressure in the oil tank is in a reasonable range, and effectively prevent the oil tank from collapsing due to low internal pressure, or due to excessive pressure. There is a high incidence of oil tank explosion safety accidents. The main principle is to set a breathing valve on the manhole cover. When the vehicle accelerates, the internal fluid activity reduces the pressure in the tank, and the breathing valve can be opened to effectively balance the internal pressure, so that the pressure in the tank will not be too low; When the tank truck slows down or is exposed to the sun, the pressure in the tank rises sharply, and the breathing valve can be opened so that the pressure in the ta...

AI Technical Summary

Problems solved by technology

At the same time, because the breathing valve is installed on the manhole cover, even if the breathing valve is qualified, there may be errors in the manufacture of the cover and the installation process with the breathing valve body, which will affect the normal function of the manhole cover.

However, there is no device and test method for detecting manhole covers at present, especially the device for detecting the entire manhole cover as a whole is particularly lacking.

In addition, as a detection system, it must have high accuracy and reliability. The accuracy of the detection results directly determines the pass rate of the product and affects whether the product can be used well.

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