對焊管件的類型

碳鋼和不鏽鋼焊接管件是連接部件，可將閥門、管道和設備組裝到管道係統上。焊接管件可與任何管道係統中的管道法蘭配合使用，並允許：

• 改變管道係統中的流動方向

• 連接或連接管道和設備

• 為輔助設備提供分支、通道和起飛

使用焊接管件的一個常見示例是通過同心異徑管變徑的管道，焊接到對焊法蘭上並連接到設備。下圖代表了對焊管件的完整集合。

LR 90 彎頭： 在管道係統中改變方向的配件稱為彎頭。方向變化以度為單位，例如 45 或 90。長半徑 90 度彎頭的中心線距彎頭端部 1.5 x NPS。 3R 彎頭的中心線距彎頭端部 3 x NPS。

LR 45 彎頭： 長半徑 45 度彎頭，方向改變 45 度。

SR90 彎頭： 短半徑 90 度彎頭與 LR90 相同，但彎頭末端到中心線之間的測量值為 1 x NPS。

LR 180 度彎頭： 長半徑 180 度回彎頭可實現完全反向流動。彎頭末端與中心線之間的距離為 3 x NPS。

SR 180 度彎頭： 短半徑 180 度回彎頭允許完全逆轉流動，但轉彎更緊。彎頭末端與中心線之間的距離為 1 x NPS。 

三通： 對焊管 三通允許從運行管道上形成 90 度分支。這允許將輔助設備連接到管道。三通焊接在管道的兩側；使分支保持打開狀態以關閉分支。 

異徑三通： 對接焊縫異徑三通有一個小於主管的分支。這允許從主管道分支到較小的管道或設備。

同心異徑管： 同心異徑管也稱為焊接同心聯軸器。它允許通過焊接將大管道連接到較小的管道。同心異徑管允許具有相同中心線的兩個管道之間的焊接連接。 

偏心異徑管： 偏心異徑管也稱為焊接偏心聯軸器。它允許將大管道焊接到具有偏移中心線的較小管道上。偏心異徑管中心線的偏移量為； 偏移 = 1/2 x（最大 ID - 最小 ID） 

焊接支管台：  Weldolet，也稱為焊接出口，是一種連接焊接接頭的方式，焊接接頭的底部輪廓與管道的輪廓相匹配。因此，焊接出口的一端焊接在管道上，而另一端則開放以焊接到任何其他管道或設備。焊接出口需要提及出口的尺寸和管道的“運行尺寸”，以便輪廓可以與管道的輪廓相匹配。焊接出口的尺寸始終小於管道尺寸，例如 1/2" 焊接出口可用於 1/2" 及更大的管道（管道尺寸）。 

焊接短管端： 短管端與搭接法蘭一起使用，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.