A clear bend specification is the fastest route to an accurate quotation and a bend that passes inspection first time. Most delays we see come from one missing detail, not from the bending itself. This checklist covers what we need to quote, and what your inspector will check at release.

1. Start with the line pipe

An induction bend is made from a straight length of pipe, the mother pipe, so the bend inherits its specification. Give us the outside diameter, wall thickness and material grade, for example API 5L X65 PSL2, plus any supplementary requirements such as sour service. If you are free-issuing pipe, tell us the mill and heat numbers so we can match certificates before bending.

2. Define the geometry

• Bend radius, as a multiple of the diameter: 3D, 5D, 7D or 10D are common. Larger radii reduce flow resistance and suit pigging.
• Bend angle, up to 90°.
• Tangent lengths at each end, which set where the field welds fall.
• Plane and orientation for compound or three-dimensional bends.

3. State the tolerances that matter

Bending stretches the outside of the arc and compresses the inside, so the specification should say how much wall thinning is acceptable at the extrados, how much ovality is allowed, and the angle tolerance. Most projects reference ISO 15590-1 or ASME B16.49; if your project specification is tighter, send it with the enquiry.

4. Agree the heat treatment

After bending, the pipe is stress relieved or quenched and tempered so the bent zone meets the same mechanical properties as the straight pipe. For sour service, give the maximum hardness so we can plan the treatment and the hardness survey.

5. List the tests and documents

Typical release testing covers ultrasonic testing of the bent zone, magnetic particle inspection of the transitions, hardness, dimensional checks, positive material identification and, where specified, hydrotesting and mechanical tests on a test bend. Tell us which tests your inspector wants to witness. Every Pipetec bend ships with its own data record, from mother-pipe heat number to delivery note.

6. Specify the finish

Note the end preparation (bevel angle), the coating system if any (PU, epoxy, FBE or 3LPE) and the marking you need on each bend.

7. Say how the bends should arrive

Delivery address, required date and packing. We can kit bends in installation order, so the crew on site opens the next bend in the sequence rather than searching a laydown area.

Sizes, grades and a drawing are enough to start. Send your bend list and we will quote within 48 hours.