The upsurge in the application of rubber seals and plastic seals in sanitary wares, doors and windows has prompted the rapid expansion of the market demand for seals, and at the same time it has also brought about quality problems for manufacturers. This topic has attracted the attention of various roles in this industry in recent years. Mainly discusses the test methods for the quality control of the sealing strip products. Here we ready several types of shower seals testing and you may get more than you want!
Why do you need a seal test report?
1. Sales use:Sell your own products and issue third-party test reports to make customers more trust in their product quality.
2. Used for research and development:During the R & D process, some difficult problems are encountered, and the problem is solved by testing the report data, thereby shortening the R & D cycle and reducing R & D costs.
3. Improve product quality:By comparing the inspection data, you can find the problems of your own products, improve product quality, and reduce production costs.
4. Simulated production:Through the formula inspection service, to test better products in the same industry, to achieve simulated production.
5. Use of research paper data.
6. Competitive bidding:some shower seals testing institutions have shorter testing periods, lower testing costs, and higher recognition, which is particularly suitable for bidding.
What angle to test the quality of the seal
Judging the quality of the sealing strip depends on the following 6 aspects of shower seals testing: Tensile performance, strength, shrinkage performance, ultra-low temperature performance, acid and alkali resistance or substance resistance and aging resistance.
1. Tensile properties
Tensile properties are the first properties to be considered for sealing materials, including: tensile strength, fixed tensile ground stress, tensile elongation at break and permanent deformation at break. Tensile strength is the larger in-situ stress that the specimen stretches to break. Constant extension stress (constant extension strain rate) is the in-situ stress achieved when the length is required. Elongation is the ratio of the length change caused by the required tensile force of the test piece to the original length. The elongation at break is the elongation when the test piece is torn. Tear-off permanent deformation is the residual deformation in the middle of the road marking after the test piece is stretched and broken.
- Strength
The strength expresses the ability of the sealing material to resist the intrusion of external forces, and is one of the basic properties of the sealing material. The strength of the raw material is related to other properties at a certain level. The higher the strength, the greater the compressive strength, the smaller the elongation, the higher the wear resistance, and the worse the cold resistance.
3. Reduce performance
Rubber products are generally shrinking. Because of the ductility of the elastomer material, the working pressure will decrease with time when it is reduced, and its main performance is to reduce stress relaxation. Reducing permanent deformation means that the original shape cannot be restored after the working pressure is removed. This situation is more pronounced in high temperature and raw oil materials, which is related to the tolerance of the sealing workability of the sealing crafts.
4. Ultra-low temperature performance
The ultra-low temperature performance is an index value for considering the ultra-low temperature characteristics of rubber products. The details of the two methods of testing ultra-low temperature performance are as follows:
1) Ultra-low temperature shrinkage temperature: pull the sealing material to a certain length, then fix it, and quickly cool it to below the freezing temperature with water, release the test piece after equilibrium, and increase the temperature at a certain rate, record the style shrinkage by 10% , 30%, 50% and 70% are expressed as TR10, TR30, TR50 and TR70 respectively. The raw material specification uses TR10 as the index value, which is related to the brittle fracture temperature of the rubber.
2) Ultra-low temperature flexibility: After the test piece is refrigerated at the required ultra-low temperature for the required time, it is bent back and forth according to the specified angle. Investigate the goodness of the sealing performance of hydraulic seals after continuous function under dynamic load at ultra-low temperature.
5. Acid and alkali resistance or substance resistance
In addition to touching crude oil bases, diesters, and silicate oils, the sealing materials sometimes touch acid, alkali and other corrosive substances in the chemical industry. In addition to being eroded in this substance, it will also cause surging and compressive strength reduction and strength reduction at high temperatures; in addition, the flame retardant and soluble chemicals in the sealing material are drawn out, resulting in quality relief and volume Becomes smaller, causing leaks. Generally, at a certain temperature, when immersed for multiple times, the quality, volume, compressive strength, elongation, and strength are measured to identify whether the sealing material is resistant to acid or alkali or substance.
6. Anti-aging properties
The sealing material is affected by the stress effect of the oxygen cylinder, trioxygen, heat, light, moisture, mechanical equipment, and its performance is affected. The aging resistance (also turned into aging resistance) can be expressed by the change of the compressive strength, elongation and strength of the embrittled style. The smaller the rate of change, the higher the aging resistance. Note: Aging resistance refers to a series of embrittlement conditions such as discoloration, discoloration, cracking, delamination and reduced compressive strength of plastic products due to external standards such as sunlight exposure, temperature changes, sunlight and rain. Among them, direct ultraviolet light is the primary condition to promote plastic embrittlement.
Leak test method to check the quality of the sealing strip
There are many leak test methods for seals, but the characteristics of each method are different. Before the shower seals testing, the appropriate leak test method should be selected according to the leak test requirements and the leak test environment.
1. Response time test method of seals
Regardless of the method used, it always takes a certain amount of time to test the leak rate. The length of the response time may affect the accuracy and sensitivity of leak test. Generally speaking, prolonging the test time will increase the sensitivity. However, if the working environment conditions change, the test time will be too long, which may reduce the test accuracy. The response time includes the response time of the test instrument itself, the lag time of the gas flow and the time required for various preparations. This must be taken into consideration when choosing a leak test method.
2. Judgment and test method of leakage points of seals
Some leak test methods can only determine whether the system is leaking, but cannot determine where the leak is. Some leak test methods can determine not only the leak point, but also the size of the leak rate. If only to find out whether the device is qualified, the former method can be used; when performing maintenance or to find the cause of the leak, the latter method must be used. Sometimes the latter method will miss the inspection.
The seal reliability test method to check the quality of the sealing strip
Although the structure of seals is diverse and the sizes are different, the reliability of seals has always been one of the most critical core issues to ensure the normal operation of the connection system. Due to the unreliable sealing, the working medium leaks, resulting in the system not working properly, the efficiency is reduced, and even the occurrence of vicious accidents has been a common example of engineering. Therefore, manufacturers and scientific research units that produce seals attach great importance to the testing of seal reliability.
The reliability of the seal refers to the ability of the connection system to maintain an effective seal within the required working time so that the leakage rate is lower than the specified index leakage rate. For this reason, various test methods require the rated test time and rated leak rate. Online shower seals testing requires that the rated testing time is very short and the rated leak rate is small. Therefore, the common requirements for various test methods are that the test accuracy must be high, the operation is simple, and the process is easy to implement, so that the test equipment can be configured on the production line to meet the needs of mass production.
1、Immersion method to test seal reliability
The immersion test method is to fill the chamber to be tested with compressed air and immerse it in water for a period of time to find if there are floating bubbles caused by leakage. Of course, you can also install a pressure gauge on the pressurized pipeline to observe the pressure change. The immersion test method is simple and easy to implement, and the investment is very small. It can test a small leak of 0.1Pa-L / s and directly determine the specific location of the leak point.
2、Pressure method to test seal reliability
The principle of this test method is to fill the chamber to be tested with compressed air, cut off the air source and maintain the rated pressure for a specified time after the air pressure reaches the working pressure. If the seal has a leakage point, the air pressure in the cavity will gradually decrease. The pressure sensor continuously converts the pressure value into an analog quantity during the rated test time and sends it to the secondary instrument for comparison with the rated value for position control.
This method needs to set a longer rated test time, but it is difficult to accept for large-scale online piece-by-piece test. In fact, when the rated test time is short, the small leakage will not be tested. If the production process does not allow to effectively extend the test time, misjudgment may occur. Currently, there are manufacturers using this test method. However, the pressure method will gradually be eliminated from the production process.
Conclusion
In summary, the test methods and test angles of seals are various, and the test mechanism can choose an appropriate method according to its own conditions and test needs. Seal inspection plays a vital role in the seal industry, because it not only provides a guarantee for the market to supply seals that comply with the standard, but also prevents accidents caused by unexpected damage to seals in the later period. Accurate shower seals testing technology escorts the healthy development of the seal industry.
About GoldRays
GoldRays is the largest manufacturer of shower seals in China. We supply a complete lineup of seals and gaskets for shower doors, glass doors and windows. Backed by our experience of over 15 years, our quality far surpasses the industry standard while managing to maintain our competitive prices. The shower seals and profiles are made from clear PVC, EVA or polycarbonate and are used for shower door sealing and various glass door applications to prevent water leakage, air infiltration and cushion impact. It works with straight, curved, pivot and sliding glass doors. With a high-standard quality control system, the product is second to none in terms of durability, transparency and rigidness.
