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原文：
Valve seals, mainly refers to the stem seal. With the valve stem to prevent media leaks movement is the central subject of dynamic seal valve. Gland form At present, the valve seals to the main gland. The basic form of stuffing: (1) gland-type This is the most used form. The same form and can distinguish many details. For example, from theBall Valves bolts, the separable T-bolt (for the pressure of ≤ 16 kg / square centimeter of the low pressure valve), stud and eyelet bolts. Speaking from the gland can be divided into integral and modular. (2) down Nut This form, shape, small size, but the pressing force is restricted to use only the small valve. Filler Stuffing inside, to fill direct contact with the valve stem and full of stuffing, to prevent media leaks. On the filler has the following requirements: (1) sealing; (2) corrosion resistance; (3) friction coefficient; (4) to adapt to medium temperature and pressure. Common fillers are: (1) asbestos packing: asbestos packing, heat and corrosion resistance are good, but when used alone, poor sealing effect, so always impregnated or attach other materials. Oil asbestos packing: its basic structure, there are two, one is a twisted system, the other is knitting. They can be divided into round and square. (2) Teflon braided packing: The packing of PTFE fine with weaving, has an excellent corrosion resistance, but also for the cryogenic medium. (3) rubber O-ring: In the low state, the seal effect is good. Temperature restricted, such Balance valves as natural rubber can only be used 60 ℃. (4) plastic molding packing: General made three-piece, it can be made into other shapes. PTFE is used in many plastics, but also use nylon 66 and nylon 1010. In addition, the use of units according to their needs, often explore effective form filler. For example, at 250 ℃ steam valve, the use of asbestos packing and co-lead by alternative Diego, the situation would reduce the steam leakage; some valves, medium constantly changing, such as the asbestos packing and Teflon tape common use, seal it better. To reduce the friction on the valve stem, in others, can be added molybdenum disulfide (M0S2), or other lubricants. Currently, new filler, is engaged in exploration. For example, PAN fiber is impregnated with PTFE emulsion, but also by pre-oxidation, sintered in the mold suppression, excellent sealing performance can be molded filler; Another example is made of stainless steel sheets and asbestos packing waveform can be high temperature , high pressure and corrosion. Bellows Seal As the chemical industry and the rapid development of atomic energy industry, flammable, explosive, toxic and radioactive substances has increased, the valve seals have more stringent requirements, some occasions, canMud Valves not use the packing seal, resulting in a new sealed form - bellows seal. This seal without filler, also called non-gasket seal. Bellows at both ends, and other parts welding die. When the stem down, the bellows expansion, as long as the bellows itself does not leak, the media can not escape. To be safe, always use the double bellows seal with the filler. Static Seals Static seal usually refers to the seal between two stationary surfaces. Sealing API Cast Steel Valves method is mainly used washer. Gasket Material (1) non-metallic materials: such as paper, linen, leather, asbestos products, plastic and rubber. Paper, linen, leather and the like, there are pores, the porous, to be used dipping oil, wax Filters or other impermeable material. General valve rarely used. Asbestos products, but also asbestos tape, rope, boards, and asbestos rubber board. Compact structure in which asbestos rubber sheet, good pressure resistance, heat resistance is also very good, and the valves in the valve itself and the pipe flange connection, is widely used
原文来自： http://www.shreveporttimes.com/article/20091205/NEWS01/91205007/1060

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以下是参考译文：

译文：如何解决阀门的动密封，静密封问题
阀门的动密封，主要是指阀杆密封。不让阀内介质随阀杆运动而泄漏，是阀门动密封的中心课题。　　填料函形式　　目前，阀门动密封，以填料函为主。填料函的基本形式是：　　(1)压盖式　　这是用得最多的形式。　　同一形式又能许多细节区别。例如，从压紧螺栓来说，可分T形化工泵
螺栓(用于压力≤16公斤/平方厘米的低压阀门)、双头螺栓和活节螺栓等。从压盖来说，可分整体式和组合式。　　(2)压紧螺母式　　这种形式，外形尺寸小，但压紧力受限制，只使用于小阀门。　　填料　　填料函内，以填料与阀杆直接接触并充满填料函，阻止介质外漏。对填料有以下要求：　　(1)密封性好; 　　(2)耐腐蚀; 　　(3)磨擦系数小; 　　(4)适应介质温度和压力。　　常用填料有：　　(1)石棉盘根：石棉盘根，耐温和耐腐蚀性能都很好，但单独使用时，密封效果排污泵
不佳，所以总是浸渍或附加其他材料。油浸石棉盘根：它的基本结构形式有两种，一种是扭制，另一种是编结。又可分圆形和方形。 (2)聚四氟乙烯编织盘根：将聚四氟乙烯细带编织为盘根，有极好的耐腐蚀性能，又可用于深冷介质。　　(3)橡胶O形圈：在低压状态下，密封效果良好。使用温度受限制，如天然橡胶只能用于60℃。　　(4)塑料成型填料：一般做成三件式，也可做成其他形状。所用塑料以聚四氟乙烯为多，也有采用尼龙66和尼龙1010的。　　此外，使用单位根据自己的需要，常常探索各种有效的填料形式。例如，在250℃蒸气阀门中，用石棉盘根和铅圈交替迭合，漏汽情况就会减轻;有的阀门，介质经常变换，如以石棉盘根和聚四氟乙烯生料带共同使用，密封效果便好些。为减轻对阀杆的磨擦，有的场合，可以加二硫化钼(M0S2)或其他润滑剂。　　目前，对新颖填料，正进行着探索。例如用聚丙烯腈纤维经聚四氟乙烯乳液浸渍，又经预氧化后，在模具中烧结压制，可以得到密封性能优异的成型填料;又如用不锈钢薄片与石棉制成波形填料，可耐高温、高压与腐蚀。　　波纹管密封　　随着化学工业和原子能工业的迅速发展，易燃、易爆、剧毒和带放射性的物质增多，对阀门真空泵
密封有了更严格的要求，有的场合已无法使用填料密封，因此产生了新的密封形式-波纹管密封。这种密封不需填料，所以也叫无填料密封。　　波纹管的两端，与别的零件焊死的。当阀杆升降时，波纹管伸缩，只要波纹管本身不漏，介质便无法泄出。为保险起见，往往采用波纹管与填料的双重密封。　　静密封　　静密封通常是指两个静止面之间的密封。密封办法主要是使用垫圈。　　垫圈材料　　(1)非金属材料：如纸、麻、牛皮、石棉制品、塑料、橡胶等。　　纸、麻、牛皮之类，有毛细孔，易渗透，使用时须浸渍油、蜡或其他防渗透材料。一般阀门很少采用。　　石棉制品，又有石棉带、绳、板和石棉橡胶板等。其中石棉橡胶板结构致密，耐压油泵
性能好，耐温性能也很好，在阀门本身和阀门与管子的法兰连接中，使用极为广泛

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