When extremely tight shutoff is required, globe and check valves may be supplied with Kel-F, Teflon or other soft inserts.

• 如果要求关闭非常紧密，那么截止阀和止回阀可能需要采用Kel-F，特氟隆（聚四氟乙烯）或其它软镶嵌件。