Return list

Test method for gas permeability of rubber airbags

Jun 05,2023

Source: Link Testing Instruments Co.,ltd.

The rubber airbag is an inflatable product, which has the characteristics of soft shape, deformable, foldable, easy to dismantle after use, and convenient to use. Common rubber airbags can be used in water blocking construction, leak detection, ship noise reduction, shock absorption, construction and other fields, by filling compressed gas to make the airbag stretch and expand to meet the cross-sectional design requirements and play a role. Take the rubber water blocking air bag as an example. This type of air bag is mainly used for water blocking operations in pipelines with water. The rubber air bag is filled with air at a certain pressure, so that the air bag fills the entire pipe, and the friction between the air bag wall and the pipe is used to block the water. For water flow, in order for the air bag to be in effective contact with the pipe wall, it is required to keep a certain amount of gas in the air bag, that is, to have good sealing and high barrier properties. Especially for rubber airbags that have been used for a long time, their barrier properties to the filling gas should be higher, so as to prevent the effect of use from being affected by the large amount of gas in the airbag permeating outward during use. Therefore, it is particularly necessary to strengthen the rubber airbag to test the gas barrier performance of filling.

Test Methods and Instruments

This test adopts the principle of pressure difference method to test the air permeability of the sample. The test process refers to GB/T 7755-2003 "Determination of the air permeability of vulcanized rubber or thermoplastic rubber". The test uses the GTC-203H differential pressure gas permeation instrument independently developed and produced by Link Testing Instruments Co., Ltd. to test the air barrier performance of the test samples.

The test principle is: GTC-203H adopts the test principle of differential pressure method, and the pre-treated sample is placed between the upper and lower test chambers and clamped. First vacuumize the low-pressure chamber (lower chamber), and then evacuate the entire system; when the specified vacuum degree is reached, close the lower chamber for testing, fill the high-pressure chamber (upper chamber) with test gas at a certain pressure, and ensure that A constant pressure difference (adjustable) is formed on both sides of the sample; in this way, the gas will permeate from the high pressure side to the low pressure side under the action of the pressure difference gradient. Various barrier parameters.

Test sample and test process

Test sample: Take the rubber water blocking air bag produced by a certain enterprise as the test sample.

Experimental procedure:

(1) Sample preparation—use a special sampler to cut 3 pieces of samples with a diameter of 97 mm from the surface of the rubber airbag sample to be tested.

(2) Sample loading——Apply a layer of vacuum grease around the test area of each test chamber, place a filter paper with a diameter of 65 mm in the test area, and then cover the prepared sample, remove the contact between the sample and the test chamber. Air bubbles, and clamp with clamping device.

(3) Parameters——set parameter information such as sample name, test temperature, test humidity, and sample thickness.

(4) Test——click the test option, the test starts, and the device automatically records the change of the lower chamber pressure, and displays the test results according to the test situation after the test is over.

Test Results and Analysis

The average air permeability of the three samples of the rubber water blocking air bag tested this time is 35.7462 cm3/(m2·24h·0.1MPa).

The barrier performance of the rubber airbag is an important factor that determines whether the gas filled inside can be preserved for a long time, and has an important impact on the performance of the airbag. In this paper, the air permeability of a rubber water-blocking air bag sample is tested. The whole test operation process is simple. Three samples are tested in one test. The test efficiency is high, the test results have good repeatability and stability, and the test accuracy is high. It reflects the barrier performance of the tested sample to air. According to the difference of the filling gas in the airbag for different purposes, the test gas can be replaced, and the barrier performance of the corresponding gas can be tested by using this method.

For more details please visit

Live Chat