Pipe Fittings
Stocking Program
Size Range | 1/4" - 36" NPS (Larger sizes available upon request)
Classes | 150, 3000, 6000*
Weld Schedules | 10, 10s, 40, 40s, 80, 80s, 120, 160 (Custom wall thicknesses available upon request)
Mechanical Brands | Victaulic, Teekay.
Stainless Steel Grades | 304, 304L, 316, 316L, 317L, 321 , 347 *
Special Alloys | 2205, 254SMo, Monel, Inconel *
Chrome Moly | P5, P9, P11, P22, P91 *
Standards | ASTM / ASME
*-Not all classes, grades available are listed or have a full inventory managed
General information
A pipe fitting is used for changing direction, branching or joining together a piping system. There are many different types of fittings and they are produced in the same sizes, schedules (wall) and materials as the pipe. The common types of fitting configurations fit into three general groups; Butt-weld, threaded (Screwed) and socket-weld.
Fitting Types
Butt-Weld Fittings
ElbowsThe standard Butt-Weld elbows come in three basic radius’s 90°, 45°, and 180°. When requesting an elbow, the default standard is the “Long Radius” but they can also be supplied in “Short Radius”. The terms "Long Radius" and "Short Radius" are important to understand. "Long Radius" means that the centre to end dimension is one and a half times the nominal pipe size. "Short Radius" means that the centre to end dimension is equal to the nominal pipe size. A 180 degree return bend is not commonly stocked, and generally needs to be produced per request.
Tees (Standard & Reducing)
The primary purpose of a Tee fitting is to make a branch from a pipe line (or run). The branch may need to be the same size as the run or it may need to be one or more sizes smaller than the run. The dimensions for Tees you must look them up on a fitting chart. For Straight Tees the centre-to-end dimension of both ends and for the branch outlet is the same. For a Reducing Tee the centre-to-end of the branch outlet is different from that of the run.
Reducers (Concentric & Eccentric)
A Reducer is a fitting used to change the line size one or more sizes smaller (or larger). There are two common versions of piping Reducers. There is Concentric Reducers- where the centre line of the inlet and the outlet are the same. With the Eccentric Reducer, one side is flat. Concentric Reducers are used mostly in situations where the reducer is in a vertical run of pipe. Eccentric Reducers are used in horizontal runs of pipe.
Caps
The weld Cap is a fitting used to close the end of a pipe in which the closed end is generally semi-elliptical in shape unless made from solid bar.
Threaded (Screwed) & Socket-Welded Fittings
Threaded and socket weld fittings are used for small diameter pipe sizes 2" NPS and down. The majority of the screwed fittings will have female (internal) threads per NPT (National Pipe Thread). The exception will be swages, plugs, and street elbows where they will have male (external) threads. Socket-Weld fittings have a deep socket into which the pipe slips and aligns itself. The weld is then made on the outer surface of the pipe and fitting.
Threaded and socket-Weld fittings are specified per the pressure class in which in stainless steel are commonly available are class 150#, 3000#, and 6000#. Cast (150#) fittings are generally used for air and water services at a low temperature and pressure, whereas forged (3000#, 6000#) fittings are normally used for higher pressures and temperatures as well as for the more complex media.
Common configurations
Elbows: There is the 90° and 45° elbow in which unlike butt-weld fittings there are no long radius or short radius options; they come as they are and cannot be "trimmed" to allow for different angle options.
Tees:The Screwed and Socket-Weld Tee fittings are used for making branches. They do come in straight and some reducing sizes.
Swages: The Screwed and Socket-Weld Swage comes in both the concentric and the eccentric shapes.
Caps and Plugs: Caps and Plugs are intended to provide for the closer of the end of a pipe or fitting.
Nipples: A Nipple is a name given to a short length of pipe. It is not really a fitting in the same context as an elbow or a Tee. Nipples are cut from pipe and can be purchased in standard lengths up to 12”.
Unions:The Union is like a coupling that can be disconnected / reconnected in which can be helpful in cases where that feature is desirable.
Outlet fittings:
A way to make branch connections on pipe and vessels is by using an out-let fitting. The main feature of the typical out-let fitting is the built-up base design which eliminates the need of any other form of branch reinforcement. The base of the standard weld out-let has a saddle shape to fit the run pipe.
You specify the fitting by the run (header) size then by the branch size. The header size is generally larger (Example: 12" x 2" Sch 40S weld out-let A/SA182-F316/316L). Out-let fittings are made with a base that covers a range of header sizes.
Weld Outlet - The outlet end of the fitting is bevelled so it can be fitted for butt welding to a pipe or another fitting. The weld out-let
Thread Outlet - The outlet end is threaded to match the normal tapered pipe threads of the pipe or equipment being attached. The threaded outlet sizes are normally limited to small diameter pipe (2" NPS and down).
Socket Weld Outlet - The outlet has a socket to match the socket welded piping fittings and pipe. The socket outlet sizes are normally limited to the small (2" NPS and down).
Lateral Outlet - A Lateral out-let sits on the run pipe at a 45° angle, and can be supplied in a butt-weld, threaded or socket weld outlet end.
Elbow Outlet - The Elbow out-let is made to be fitted on the back side of a long radius 90° elbow, and can be supplied in a butt-weld, threaded or socket weld outlet end.
Nipple Outlet - A Nipple out-let is a fitting that has the reinforced base for attaching to the run pipe and then has a short pipe extension with a threaded or plain outlet end.