焊接与银钎焊SOLDERING AND SILVER BRAZING

务必记住所推荐的阀门的用途是什么，并对所应用的环境进行分析，这样才能决定选用最适合安装什么样的阀门。在安装正确的阀门之前，为了防止损坏阀门，并保证充分发挥阀门的工作性能，请阅读一下安装指南：Analyze the application to determine which valve is best suited for installations, keeping in mind the service for which the valve is recommended. Before installing the correct valve, review the installation instructions to prevent damage to the valve and to assure its maximum efficiency：

先沿着垂直方向切割管道，并修整、去除毛刺，测量管径。Cut tube end square. Ream, burr and size.

使用纱布或钢丝刷清除管道和切割部位，使其金属表面发光发亮。建议不要使用钢丝绒。Use sand cloth or steel wire brush to clean both ends to a bright metal finish. Steel wool is not recommended.

在管道的外面和焊接罩的内部涂上焊剂，焊剂必须完全覆盖焊接表面。请有节制地使用焊剂。Apply flux to outside of tube and inside of solder cup. Surfaces to be joined must be completely covered. Use flux sparingly.

要确保阀门处于开启状态。先对管道加热。尽可能多的将热从管道传递到阀门。避免延长阀门本身的加热时间。Be sure that valve is fully open. Apply heat to tube first. Transfer as much heat as possible through tube into valve. Avoid prolonged heating of valve itself.

银钎焊的方法：对需要进行钎焊的部件进行组装。如果允许涂上焊剂的部件处于直立状态，那么焊剂中的水分会蒸发掉，而干燥的焊剂很容易脱落，致使暴露的金属表面容易被氧化。在进行连接组装时，要将管道插入管套直到遇到阻挡为止。组装是要保证有稳固的支撑，使得整个钎焊操作过程中能够保持在直线位置。Silver Brazing Method: Assemble parts to be brazed. If fluxed parts are allowed to stand, the water in the flux will evaporate, and dried flux is liable to flake off, exposing metal surfaces to oxidation. Assemble joint by inserting tube into socket hard against the stop. The assembly should be firmly supported so that it will remain in alignment during the brazing operation.

注：对于1英寸或更大公称通径的阀门，一次性将连接部件加热到所需温度比较困难。为了在整个大面积上保持正常的温度，通常情况下需要两个焊枪。建议对整个管套区域进行适当的预热。建议采用乙炔火焰对连接部件进行加热。首先从离阀门1英寸的地方开始对管道进行加热，然后围绕着管道短距离上下交替对管道进行火焰烘烤，并以适当的角度旋转管道，避免烧穿管道。火焰要连续运动，不允许停留在某一点上。NOTE: On one-inch and larger valves, it is difficult to bring the whole joint up to temperature at one time. It will frequently be found desirable to use a double-tip torch to maintain the proper temperature over the larger area. A mild pre-heating of the whole socket area is recommended. Apply heat to parts to be joined. The preferred method is by oxy-acetylene flame. Heat tube first, beginning one inch from edge of valve. Sweep flame around tube in short strokes up and down at right angles to run of tube. To avoid burning through tube, the flame should be in continuous motion and not allowed to remain on any one point.

在阀门的套筒底座用火焰进行烘烤。加热要均匀，用火焰对阀门及管道进行火焰烘烤的过程要延续到阀门上的焊剂不再发出声音。不要对阀门过度加热。Apply flame to valve at base of socket. Heat uniformly, sweeping flame from valve to tube until flux on valve becomes quiet. Avoid excessive heating of valve.

当焊剂变成液态并且在管道和阀门上呈现半透明状态时，开始将火焰沿着连接部件的轴线进行进退烘烤，以保持连接部件、特别是阀门套筒底座部位的热度。When flux appears liquid and transparent on both tube and valve, start sweeping flame back and forth along axis of joint to maintain heat on parts to be joined, especially toward base of valve socket.

使用适量的焊料：如果使用线状焊料，那么对公称通径为3/4英寸的阀门就要采用3/4英寸的焊料，等等。如果使用的焊料太多，那么有些焊料可能会流过管道阻挡部位，并堵塞密封区域。在安装连接部件时，可以看到焊料和钎焊合金继续流动Use just enough solder: with wire solder, use 3/4" for a 3/4" valve, etc. If too much solder is used, it may flow past tube stop and clog sealing area. When joint is filled, a continuous run of solder or brazing alloy will be visible.

银钎焊法：将焊线或焊杆点在阀门里的管道套座上。当焊杆或焊线进入连接处时要将火焰从其上面移开。当合金流进连接处时，要前后移动火焰。达到适当的温度后，合金将迅速容易地流进管道外壳和阀门套管之间的空间。连接处被充满后，就会看到焊接合金的边缘。Silver Brazing Method: Apply brazing wire or rod at point where tube enters valve socket. Keep flame away from rod or wire as it is fed into the joint. Move flame back and forth as alloy is drawn into joint. When the proper temperature is reached alloy will flow readily into space between tube outer wall and valve socket. When joint is filled, a continuous rim of brazing alloy will be visible.