对焊管件的类型

碳钢和不锈钢焊接管件是连接部件，可将阀门、管道和设备组装到管道系统上。焊接管件可与任何管道系统中的管道法兰配合使用，并允许：

• 改变管道系统中的流动方向

• 连接或连接管道和设备

• 为辅助设备提供分支、通道和起飞

使用焊接管件的一个常见示例是通过同心异径管变径的管道，焊接到对焊法兰上并连接到设备。下图代表了对焊管件的完整集合。

LR 90 弯头： 在管道系统中改变方向的配件称为弯头。方向变化以度为单位，例如 45 或 90。长半径 90 度弯头的中心线距弯头端部 1.5 x NPS。 3R 弯头的中心线距弯头端部 3 x NPS。

LR 45 弯头： 长半径 45 度弯头，方向改变 45 度。

SR90 弯头： 短半径 90 度弯头与 LR90 相同，但弯头末端到中心线之间的测量值为 1 x NPS。

LR 180 度弯头： 长半径 180 度回弯头可实现完全反向流动。弯头末端与中心线之间的距离为 3 x NPS。

SR 180 度弯头： 短半径 180 度回弯头允许完全逆转流动，但转弯更紧。弯头末端与中心线之间的距离为 1 x NPS。 

三通： 对焊管 三通允许从运行管道上形成 90 度分支。这允许将辅助设备连接到管道。三通焊接在管道的两侧；使分支保持打开状态以关闭分支。 

异径三通： 对接焊缝异径三通有一个小于主管的分支。这允许从主管道分支到较小的管道或设备。

同心异径管： 同心异径管也称为焊接同心联轴器。它允许通过焊接将大管道连接到较小的管道。同心异径管允许具有相同中心线的两个管道之间的焊接连接。 

偏心异径管： 偏心异径管也称为焊接偏心联轴器。它允许将大管道焊接到具有偏移中心线的较小管道上。偏心异径管中心线的偏移量为； 偏移 = 1/2 x（最大 ID - 最小 ID） 

焊接支管台：  Weldolet，也称为焊接出口，是一种连接焊接接头的方式，焊接接头的底部轮廓与管道的轮廓相匹配。因此，焊接出口的一端焊接在管道上，而另一端则开放以焊接到任何其他管道或设备。焊接出口需要提及出口的尺寸和管道的“运行尺寸”，以便轮廓可以与管道的轮廓相匹配。焊接出口的尺寸始终小于管道尺寸，例如 1/2" 焊接出口可用于 1/2" 及更大的管道（管道尺寸）。 

焊接短管端： 短管端与搭接法兰一起使用，焊接到管道上。 

Types of Butt Weld Pipe Fittings

Welded pipe fittings in carbon steel and stainless steel are the joining components that make possible the assembly of valves, pipes and equipment onto the piping system. Welded fittings compliment pipe flanges in any piping system and allows:

• Change direction of flow in a piping system

• Connect or joint pipes and equipment

• Provide branches, access and takeoffs for auxiliary equipment

A common example using welded pipe fitting is a pipe reduced by concentric reducer, welded to a weld neck flange and connected to equipment. The figure below represents a complete collection of butt welded pipe fittings.

LR 90 Elbow: Fittings that change direction in a piping system are called elbows. The directional change is given in degrees, such as 45 or 90. Long radius 90 degree elbow has the center line of elbow at 1.5 x  NPS from elbow end. 3R elbow has center line at 3 x NPS from elbow end.

LR 45 Elbow: Long radius 45 degree elbow changes the direction by 45 degrees.

SR90 Elbow: Short Radius 90 degree elbow is the same as LR90, except for the measurement between end of elbow to the center line is 1 x NPS.

LR 180 degree Bend: Long Radius 180 degree return bend allows complete reversal of flow. The distance between end of elbow and the center line is 3 x NPS.

SR 180 degree Bend: Short Radius 180 degree return bend allows complete reversal of flow but in a much tighter turn. The distance between end of elbow and the center line is 1 x NPS. 

Tee: Butt weld pipe Tee allows a 90 degree branch off from a running pipe. This allows for connecting auxiliary equipment to a pipe. A tee is welded on both sides to the pipe; leaving the branch open for branch off. 

Reducing Tee: Butt weld reducing tee has a branch that is smaller than the main run. This allows for branching off to a smaller pipe or equipment from the main run.

Concentric Reducer: A concentric Reducer is also called welded concentric coupling. It allows for connecting a large pipe to a smaller pipe by means of welding. A concentric reducer allows a welded connection between two pipes with the same center line. 

Eccentric Reducer: An eccentric reducer is also called welded eccentric coupling. It allows for welding a large pipe to a smaller pipe with an offset center line. The offset of the center line in an eccentric reducer is; Offset = 1/2 x (Largest ID - Smallest ID) 

Weldolet: A weldolet, also called welding outlet, is a way of connecting a welded connection that is contoured at the bottom to match the contour of the pipe. So one end of the welding outlet is welded on the pipe, whereas the other end is open to be welded to any other pipe or equipment. A welding outlet requires mentioning the size of out let and the "Run Size" of pipe so the contour can match the contour of the pipe. The size of the welding outlet will always be smaller than run size such as 1/2" welding outlet can be used on pipe (run size) 1/2" and bigger. 

Welded Stub End: Stub ends are used with lap joint flange to be welded onto the pipe.