First, we clarify the "seal". sealed at least can be divided into the following categories: mechanical seals, hydraulic and pneumatic seals, oil seals, O-rings, packing and padfilm, or even more. Each category there are many subclasses. So many categories to form a common name "sealing". Visible, and sealing member is a very complicated and broad categories.

　　The seal is a discipline? Should be said that most engineering schools do not have the discipline. With a lay person to talk aboutthe sealing, or mentioned in reunions and family gatherings we are engaged in the sealing industry, ten people have seven or eightwould think bees buzzing fly. Counterparts engaged in sealing this experience? Seal the visibility is very low for most people, thepopularity of the bee is very high.

　　Since the visibility is so low, why opening discussion of this problem? Because if you talk with the sealing industry, would have heard a completely different argument. These companies often expounded their seals particularity, the difficulty of making, and the importance of passion. While everyone understand the concept of "sealing" are very different, they tend to think that their own kind ofseal is the most important seal. For example, they will passionately describes what is packing? (If they are doing the packing) What is the mechanical seal? (If they do the mechanical seal) What is the hydraulic seal (if they do hydraulic seals). . . What is the O-ring. .. In their eyes, they do seal is a big market; and other types of sealing is not important, or other sealed form simply does not need to exist.

　　Sealing large and small, in the understanding between the layman and expert inside, Why is there such a big difference? This is ofthe sealing industry users inside the minds of "seal and seal is the understanding of dislocation . I believe that one of the reasonsthat this understanding of dislocation, it is difficult for a lot of sealing companies to communicate with customers.