原文：
1 　概述 金属波纹管阀门的波纹管下端焊接在阀杆上,以防止工艺流体浸蚀阀杆, 另一端置于阀体和阀盖之间构成静密封。采用合适的材料, 波纹管阀可用于高温500 ℃和高压2 500 lb (42 MPa) 工况中。 通常阀门行程为波纹管自由长度的15 % , 因而波纹管占据很大的压力空间, 制造工艺相对复杂, 价格较贵。但与传统填料密封阀门相比, 阀杆的密封更加可靠, 在外泄漏要求比较严格的场合, 如有毒介质、强腐蚀介质和放射性介质以及热油等场合中应用广泛。 2 　设计要求 波纹管阀门最常用的结构形式为波纹管截止阀和闸阀。波纹管截止阀因为其启闭行程短, 易于制造与之匹配的波纹管而使用广泛。闸阀由于需要的行程较长, 制造波纹管的难度增大, 使大口径波纹管闸阀的使用受到限制。 211 　阀门寿命 波纹管阀门的全开2全关2全开过程为一个循环(一次) , 美国阀门和管件制造者标准协会MSS SP2117 规定波纹管阀门寿命如表1 。在不同的工况条件下, 波纹管阀门的寿命要求也不一样, 设计时应满足客户的具体要求。 212 　阀门试验 波纹管阀门的试验分为型式试验和产品试验。 21211 　型式试验 波纹管阀门的关键部件是波纹管。波纹管的型式试验可以是波纹管阀门, 也可以是用连波纹管的工装, 但工装的载荷、行程、压力和间隙等应与实际的波纹管阀门相同。型式试验前先完成115 倍设计压力的强度试验。型式试验应从每一基本设计和材料中随机抽取至少3 台试验, 最短寿命不低于规定。试验温度为常温, 试验压力为常温时材料规定的工作压力。寿命试验结束后用016 MPa 的空气试压, 波纹管及其连接接头进入水中, 观察是否有气泡产生。或用氦气检漏仪器测试, 其泄漏率不大于10 - 6cm3/ s。 21212 　产品试验 每台波纹管阀门除正常的阀门试验外, 还必须使用氦气检漏仪器测试, 其泄漏率不大于10 - 6cm3/ s。

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译文：
1 Overview Metal bellows bellows valve stem on the bottom welded to prevent the erosion process fluid stem, put the other side of body and constitute a static seal between the valve cover. Use of appropriate materials, bellows valves for high temperature 500 ℃ and high-pressure 2 500 lb (42 MPa) conditions in the. Bellows valve is usually free for the length of stroke 15%, which occupy a lot of pressure bellows space, manufacturing process is relatively complex and more expensive. However, compared with traditional packing seal valves, valve stem seal is more secure, leak outside the strict requirement of the occasion, such as toxic medium, strong corrosive medium and the radioactive medium, and hot oil is used widely occasions. 2 design Bellows valve structure of the most common form of bellows globe valve and gate valve. Bellows globe valve because of its open and close a short trip, easy to manufacture bellows matched widely used. Valve due to the need of the trip is longer, more difficult manufacturing bellows, so that large diameter bellows valve use is limited. 211 valve life Bellows valves fully open two full off 2 full-process as a cycle (once), the U.S. manufacturer of valves and pipe fittings Standards Association MSS SP2117 provides bellows valve life in Table 1. Different working conditions, the corrugated pipe valve life requirements are not the same, the design should satisfy the customer's specific requirements. 212 Valve Test Bellows type valve test is divided into test and product testing. 21 211 type test Bellow is a key component of the valve bellows. Bellows type test can be bellows valves, can also be used with bellows of tooling, but the tooling of the load, stroke, pressure and gap should be the same as the actual bellows valves. Type test before the completion of the design pressure of 115 times the strength test. Type tests should be the basic design and materials of each randomly test at least 3 units, not less than the minimum life requirements. Test temperature is room temperature, the test pressure required for the normal temperature materials work pressure. After life test with 016 MPa of air pressure test, bellows and connectors into the water, see if there is bubbles. Or helium leak testing device, the leakage rate of no more than 10 - 6cm3 / s. 21212 Product Test Bellows valves each valve test than normal, but also must use the helium leak test device, the leakage rate of no more than 10 - 6cm3 / s.