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Pipe bending

The pipe bending is used to change the direction of run of pipe.

Pipe bending is any metal forming processes used to permanently form pipes or tubing.


Pipe bending reference

Just before the final delivery, our merchandise are stringently checked by a team of quality analyzers on varied parameters, which guarantee their flawlessness and durability. In addition, clients can avail these goods from us at competitive rates.

Standard

ASTM

Description

  • ASME/ANSI B16.49 Factory-Made Wrought Steel Buttwelding Induction Bends for Transportation and Distribution Systems
  • ASTM A403 Standard Specification for Wrought Austenitic Stainless Steel Piping Fittings
  • ISO 2851 tainless steel bends and tees for the food

JIS

  • JIS B2311 Universal steel butt-welding pipe fittings
  • JIS B2312 Steel butt-welding pipe fittings
  • JIS B2313 Steel plate butt-welding pipe fittings
  • JIS B 2321:1995Aluminium and aluminium alloy butt-welding pipe fittings

EURO

  • DIN 3867 Non-soldering compression couplings – Pressure bush for butt joints
  • DIN 2609 Steel butt-welding pipe fittings; technical delivery conditions
  • BS 1640 Specification for steel butt-welding pipe fittings for the petroleum industry
  • BS 1965 Butt welding pipe fittings for pressure purpose
  • STPG38

Materials

They are manufactured utilizing higher grade raw material, advanced machines and technologies.

Abrasion resistant: Cearmic lined, Ceramic tile, Bi-metal clad pipe bending, Rare earth alloy wear-resistant pipe bending
Carbon steel:
SA234 WPB, SA234 WPC,SA42 WPL6, SA42 WPL3
WP1. MSS-SP75, WPHY,WPHY 46,WPHY 52
WPHY 56,WPHY 60,WPHY 65, WPHY 70
DIN 1629 St37, RST37.2 St52, STPG38
Stainless:
ASTM/ASME SA403 304,304L ,316, 316L, WP304L, 3 WP316 WP347 (H) ,WP317 (L),WP321.
DIN 1.4301, 1.4306, 1.4401, 1.4571
JIS SUS304,SUS304, SUS304L, SUS316, SUS316
Alloy:
ASTM/ASME SA234 WP12, WP11,WP22, WP5, WP9, WP91, ASTM B361 GR.3003-6061, ASTM B366 UNS
N04400,N08800, N08825 N1001-N10276-N10665, WPT2-WPT12
ASTM 182 F1, F5, F6, F7, F9, F11, F12, F22, F51, 16MnR Cr5Mo
12Cr1MoV 10CrMo910 15CrMo 12Cr2Mo1, St45.8


Abrasion resistant Bend & elbow

Pipe bend FAQs

Pipe fittings are necessary to join together pipes, or to change the direction of an existing pipe. Pipes and pipe fittings are made of a variety of materials, depending on the fluid or gas being transported. Most pipe fittings tend to be either threaded or able to slip over the pipes they connect. Whether you are using steel pipes of PVC pipes, a chemical solvent is required to create a seal between the pipe and the fittings.

Measure the required length of the pipe to be installed, keeping in mind the extra length required where the pipe will be inserted into the fitting. Mark this length on the pipe.


How to distinguish between pipe elbow and pipe bending?

Piping Elbows and Bends are very important pipe fitting which is used very frequently for changing direction in the piping system. Piping Elbow and Piping bend are not the same, even though sometimes these two terms are interchangeably used.

Pipe elbows and pipe bends are both very common pipe fittings products which are used to change the flowing direction in a piping systems.Some times they are interchangeable,but not same.

What is a Piping Bend?

A PIPING BEND is simply a generic term in piping for an “offset” – a change in direction of the piping. It signifies that there is a “bend” i.e, a change in direction of the piping (usually for some specific reason) – but it lacks specific, engineering definition as to direction and degree. Bends are usually made by using a bending machine (hot bending and cold bending) on-site and suited for a specific need. The use of bends is economic as it reduces the number of expensive fittings.

What is a Piping Elbow?

A PIPING ELBOW, on the other hand, is a specific, standard, engineered bend pre-fabricated as a spool piece (based on ASME B 16.9) and designed to either be screwed, flanged, or welded to the piping it is associated with. An elbow can be 45 degrees or 90 degrees. There can also be custom-designed elbows, although most are categorized as either “short radius” or long radius”.

Elbow Radius

Elbows or bends are available in various radii for a smooth change in direction which is expressed in terms of pipe nominal size expressed in inches. Elbows or bends are available in three radii, a. Long radius elbows (Radius = 1.5D): used most frequently where there is a need to keep the frictional fluid pressure loss down to a minimum, there are ample space and volume to allow for a wider turn and generate less pressure drop. b. Long radius elbows (Radius > 1.5D): Used sometimes for specific applications for transporting high viscous fluids likes slurry, low polymer, etc. For radius, more than 1.5D pipe bends are usually used and these can be made to any radius. However, 3D & 5D pipe bends are most commonly used b. Short radius elbows (Radius = 1.0D): to be used only in locations where space does not permit the use of long radius elbow and there is a need to reduce the cost of elbows. In jacketed piping, the short radius elbow is used for the core pipe. Here D is nominal pipe size in inches. There are three major parameters that dictate the radius selection for the elbow. Space availability, cost and pressure drop. Pipe bends are preferred where pressure drop is of major consideration. The use of short radius elbows should be avoided as far as possible due to abrupt change in a direction causing the high-pressure drop.

Minimum thickness requirement

Whether an elbow or bend is used the minimum thickness requirement from code must be met. Code ASME B 31.3 provides an equation for calculating minimum thickness required (t) in finished form for a given internal design pressure (P) as shown below:

Code Equation for Minimum Elbow Thickness Calculation

Here,

R1 = bend radius of welding elbow or pipe bend
D = outside diameter of the pipe
W = weld joint strength reduction factor
Y = coefficient from Code Table 304.1.1
S = stress value for material from Table A-1 at the maximum temperature
E = quality factor from Table A-1A or A-1B Add any corrosion, erosion, mechanical allowances with this calculated value to get the thickness required.

End Connections

For connecting elbow/bend to pipe, the following type of end connections are available

  • Butt-welded: Used along with large bore (>=2 inch) piping
  • Socket welded: Used along with pipe size
  • Grooved end: A grooved end fitting has a groove or shoulder along the edge. This fittings groove allows for a seal without the need for welding.
  • Flanged: Flange connections are very important in the petroleum and chemical industries, and bolts and nuts are an essential part of them.

How to Calculate a Pipe Bend?

Pipe fittings are necessary to join together pipes, or to change the direction of an existing pipe. Pipes and pipe fittings are made of a variety of materials, depending on the fluid or gas being transported.

Most pipe fittings tend to be either threaded or able to slip over the pipes they connect. Whether you are using steel pipes of PVC pipes, a chemical solvent is required to create a seal between the pipe and the fittings.

Measure the required length of the pipe to be installed, keeping in mind the extra length required where the pipe will be inserted into the fitting. Mark this length on the pipe.

Whether you are bending pipe for running electrical conduit or a metal project, calculating the bend for the start and end point can be an important factor. While there are different types of pipe benders on the market, they all share a common identification for the operation. Identified on all pipe benders is the size of pipe the unit will bend along with a number called the “take up.” The take up measurement is used for adding or deducting an allowance in the overall length of the bend. By following a basic process, you can calculate pipe bends regardless of the type of bender or the diameter of pipe.

Identify the take up measurement that is located on the pipe-bending shoe itself. This is the addition or deduction of measurement to the length of pipe from the front mark on the bending shoe. Also be aware that there is a second center-of-bend mark located approximately in the center of the bending shoe. Also located along the running length of the shoe are angle markings with lines. These numbers and lines correspond to actual angles that can be bent into the pipe by aligning the pipe with the angled line marked on the outside of the shoe.

Bend a 90-degree angle on a ½-diameter pipe with a ½-inch bender. The process will remain the same for different sized pipes and benders, but only the take up measurement will be different. Identified on the shoe for the ½-inch pipe may be the wording “stub take up 5 inches from arrow or line.” The 5 inches is the amount you will deduct from the overall length of the 90-degree bend measurement.

Use the measuring tape and pencil and place a mark at 12 inches from the end of the pipe. This will be the distance from the bend to the end of the pipe. By using the deduction measurement on the shoe, measure back 5 inches from the 12-inch mark and make a solid pencil line.

Lay the pipe on a level surface and insert the pipe into the bender. The solid pencil mark should be placed 5 inches back from the 12-inch mark and should be aligned with the front mark or arrow on the bending shoe. Pull back on the handle in a smooth motion until the pipe sits at a 90-degree position to the level surface. Place the small level against the upright portion of the pipe and check for level. This will give you a perfect 90-degree bend. Check the height of the overall bend by placing the end of the tape measure on the level base and measure the end of the pipe. It should read 12 inches exactly.

Practice with other angled bends by using the deduction measurement and the center of the bend mark on the shoe. All pipe benders may have their own quirks and slight measurement adjustments that will have to be done. The actual end result also depends on how well and secure you hold the pipe in the bender, prior to the first bend you place on the pipe.


Bevelled Ends

The ends of all buttweld fittings are bevelled, exceeding wall thickness 4 mm for austenitic stainless steel, or 5 mm for ferritic stainless steel. The shape of the bevel depending upon the actual wall thickness. This bevelled ends are needed to be able to make a “Butt weld”.

Welding Bevel acc.to ASME / ANSI B16.9 and ASME / ANSI B16.28

ASME B16.25 covers the preparation of buttwelding ends of piping components to be joined into a piping system by welding. It includes requirements for welding bevels, for external and internal shaping of heavy-wall components, and for preparation of internal ends (including dimensions and dimensional tolerances).

Our in-hourse R&D team developed bevel ends equipment are good using in thickness 2mm to 20mm pipe fittings, guarantee high efficiency and high quality.

Send us your technical drawings

These weld edge preparation requirements are also incorporated into the ASME standards (e.g., B16.9, B16.5, B16.34).

ASME B16.25

ASME B16.25 sets standards for the preparation of the ends of components that need to be welded together.

Cut square or slight chamfer, at manufacturer’s option for :

  • t ≤ 0.19” carbon steel or ferritic alloy steels
  • t ≤ 0.12” austenitic alloy steels

Buttweld Fittings general

A pipe fitting is defined as a part used in a piping system, for changing direction, branching or for change of pipe diameter, and which is mechanically joined to the system.

There are many different types of fittings and they are the same in all sizes and schedules as the pipe.