What are pipe elbows?

Pipe elbows are used to be installed between two lengths of pipe or tube allowing a change of direction,usually these elbows distinguished by connection ends. The ends of pipe elbows may be machined for butt welding , threaded , or socketed , so the elbows are consist of butt weld,thread elbow, socket elbow and other series.

Definition of Pipe elbows

An elbow is a pipe fitting installed between two lengths of pipe or tubing to allow a change of direction, usually a 90° or 45° angle, though 22.5° elbows are also made. 

The ends may be machined for butt welding, threaded (usually female), or socketed, etc. When the two ends differ in size, the fitting is called a reducing elbow or reducer elbow.

Pressure: SCH5 to SCH160
Size range: 1/2 to 56 inches (DN 15 to DN 1,400mm), 22.5 Deg, 45 Deg, 90 Deg, 180 Deg
Manufacturing standards: ANSI, ISO, JIS and DIN

Process: butt welding, seamless, threaded , or socketed

90° Elbow:

90° elbow, also called “90 bends or 90 ells”, are manufactured as SR (Short Radius) elbows and LR (Long Radius) elbows. SR (Short Radius) elbows have a Center-to-Face dimension of 1.0 X diameter and are typically used in tight areas where clearances are an issue. LR (Long Radius) elbows have a Center-to-Face dimension of 1.5 X diameter and are the more common type and used when space is available and flow is more critical.

 

45° Elbow:

The function of a 45° elbow is the same as a 90° elbow, but the measurement of dimensions is different to that of the 90° elbow.

The radius of a 45° elbow is the same as the radius of the 90° LR (1½D). However, the center to face dimension is not equivalent to the radius as in 90° LR elbows. This is measured from each face to the point of intersection of the center lines perpendicular to each other, distances B on the image. This is due to the smaller degree of bend. Short radius 45° elbows are not available.

Applications of pipe elbows:

Various applications of pipe elbows are as follows:

They are manufactured to be used in flow lines for gases, fluids in industrial processes, medical, construction and many other specialized applications.

The elbows are constructed of heavy materials for rigid applications like extreme high/low temperature resistance etc.

The elbows are specifically designed for use on process and control systems, instrumentation, and equipment used in chemical, petroleum, fluid power, electronic and pulp and paper plants.

   

Types of 90° elbows:

90° elbows are manufactured as SR (Short Radius) elbows and LR (Long Radius) elbows:

Long and Short Radius

Pipe ebows are split into two groups which define the distance over which they change direction; the center line of one end to the opposite face. This is known as the "center to face" distance and is equivalent to the radius through which the elbow is bent.
The center to face distance for a "long" radius elbow, abbreviated LR always is "1½ x Nominal Pipe Size (NPS) (1½D)", while the center to face distance for a "short" radius elbow, abbreviated SR even is to nominal pipe size.

SR (Short Radius) Elbows:

These elbows have a Center-to-Face dimension of 1.0 X diameter. They are typically used in tight areas where clearance is the main issue.

LR (Long Radius) Elbows:

These elbows have a Center-to-Face dimension of 1.5 X diameter. They are the most common type of elbow and used when space is available and flow is more critical.

Reducing Elbow:

A reducing elbow is a type of fitting which is used to join two pieces of pipe of different sizes. The reducing elbow is so called because it looks like a reducing piece and elbow combined into one. Reducing elbows have different sized openings on each end and hence they can connect two different sized pipes. They are available in different materials, sizes, finishes and colors.

45° Pipe Elbow:

45° Pipe Elbow is also known as “45 bends or 45 ells”. The 45° pipe elbow is used to connect tubes at a 45° pipe angle. As the name suggests, this is a pipe fitting device which is bent in such a way to produce 45° change in the direction of flow of the fluid/gas in the pipe.

Like a 90° elbow, the 45° pipe elbow also attaches readily to pipes of various materials like plastic, copper, cast iron, steel, lead, rubber etc. They are typically made as LR (Long Radius) elbows. These types of elbows are available in various sizes (in mm or inches). They are available with different male to female BSP thread connections. Providing a wide choice of colors, these 45° elbows can be manufactured to meet different specifications, in terms of size and diameter.

Male Pipe Elbows & Female Pipe Elbows:

Male pipe elbows and female pipe elbows are popular tube fittings which provide an angled change in the direction of a tubing run. While a male pipe elbow is used to connect fractional tube to female tapered pipe thread, a female elbow is used to connect fractional tube to male NPT thread. These types of tube fittings like male elbows and female elbows have been specifically designed for use on instrumentation, process and control systems and equipment employed in chemical, petroleum, fluid power, electronic and pulp and paper plants.

The most applied version is the 90° long radius and the 45° elbow, while the 90° short radius elbow is applied if there is too little space. The function of a 180° elbow is to change direction of flow through 180°. Both, the LR and the SR types have a center to center dimension double the matching 90° elbows. These fittings will generally be used in furnesses or other heating or cooling units.

Dimensions, dimensional tolerances and more images, can be found in the main Menu "Fittings".

In addition to the defined elbows, there is the Reducing Elbow, which is a elbow with various diameters on the ends. Because this elbow, for many suppliers it is not a standard item, and thus probably a high price with a long delivery time, the use of a "normal" elbow with a separate reducer is an option if the situation allows.

Reducing elbow 90°

Other degrees elbows can be machined from a standard elbow. Longer radius type, the center to face dimension e.g. is three times the nominal size (3D), even is available.

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