The ingenious way to distinguish the good and bad quality of valves
There are too many differences in the quality of valves in the market today. If you are a little careless, you will buy products with poor quality. High quality valve manufacturers will teach you how to distinguish between good and bad valve quality.
1. Medium weight increase test: it is possible to take samples from waste products, soak them in one or several selected media, weigh them after a certain temperature time, and infer the type of data according to the weight change rate and hardness change rate. For example, after soaking in 100 degree engine oil for 24 hours, NBR, fluororubber, ECO, CR quality and hardness change rate are very small, while NR, EPDM, SBR weight increase is more than twice, and the hardness change is large, and the volume shrinkage is obvious
2. Extinguishing method: take a few samples and burn them in the air. Observe the phenomenon. Generally speaking, fluorogel, CR, and CSM will self extinguish after ignition. Even if the flame is ignited, it is much smaller than that of ordinary NR and EPDM. Of course, if we carefully observe, the extinction status, color, and smell will also provide us with a lot of information. For example, when NBR/PVC is used together with glue, the fire will sputter when there is a fire source, as if there is water, the fire will self extinguish after ignition, The smoke is thick and sour. It should be noted that sometimes the adhesive added with flame retardant but without halogen will extinguish from the fire, which should be further inferred by other methods
3. Hot air aging test: take samples from waste products and put them in an aging chamber for one day to observe the aging phenomenon. Gradual aging can gradually increase the temperature. For example, CR, NR, SBR will be brittle at 150 degrees, NBR EPDM will be elastic, and ordinary NBR will be brittle at 180 degrees; The HNBR will also be brittle at 230 degrees, and the fluorine glue and silica gel still have good elasticity
4. Measuring specific gravity: use an electronic scale or analytical balance, accurate to 0.01g, and add a glass of water and a hair. Generally speaking, the proportion of fluorine glue is larger than 1.8, and the proportion of CR ECO is more than 1.3. It can be considered that these glue are obviously larger
5. Low temperature method: take samples from waste products, use dry ice and alcohol to create a suitable low temperature environment. Soak the samples in a low temperature environment for 2-5 minutes, and feel the soft and hard level at the selected temperature. For example, under - 40 degrees, silica gel and fluorine gel, which are also good at high temperature and oil resistance, are comparable, while silica gel is relatively soft Dr. Joseph Juran, a famous American quality management scientist, said that "the 20th century is the century of consumption rate, and the 21st century is the century of quality". Quality is the soul of products and the life of enterprises. As long as I guarantee my quality, it is the way for an enterprise to survive. To provide you with high-quality products, we are constantly striving to be a professional consumer manufacturer of electric butterfly valve pneumatic tires.