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Pipe Bend After Fitting

Pipe Bend After Fitting

Pipe Bend After Fitting


This may be a very simple question, but I am looking at creating an alignment for an 8" HDPE SDR 17 pipeline. I am trying to keep to the angles used by pipe fittings, but in some cases I get a 40 degree angle rather 45 degree angle. Is there anywhere I can for formulas for pipe bending after a fitting? Should I should assume the minimum turning radius (I have that formula) for a pipe the pipe after the fitting?

P.S. I have plenty of room for the pipe to turn...


RE: Pipe Bend After Fitting

Get a 45 degree elbow.

Get a bandsaw large enough to pass the 8 inch dia pipe.

Cut 5 degrees off.

Reprep the joint.

RE: Pipe Bend After Fitting

To correct/audit myself: If you are trying to "force" a 40 degree bend through a 45 fitting with a solvent-welded type joint, you will likely fail.

If you can't adjust your start or end points to accommodate a real 45 degree elbow, try inserting a 90 elbow, with the outlet aimed "vertically" up from your x,y plane.

Add a stub lenght of vertical pipe, then another 90. But this puts the second 90 directly above your starting point, except the second 90 CAN be rolled to the 40 degree you want. (Or any other angle actually)

Run the straight pipe from that elbow, now "lifted" in z by the 2x 90 elbows to the desired end point at the 40 degree angle you demand, then add two more 90 elbows.

The first to aim "down" and the second to resume the direction you want.

OK, you've solved one problem, but you have increased fabrication time, material cost, and the flow resistance

RE: Pipe Bend After Fitting

8" HDPE SDR17 pipe should be able to flex 5 deg very easily .... especially considering that you have plenty of room.

RE: Pipe Bend After Fitting

Why don't you order a 40 degree bend in your 8 inch and whatever SDR and electrofuse it?

Richard A. Cornelius, P.E.

RE: Pipe Bend After Fitting

Check the minimum radius, then use the maximum you can fit into the space available ... or less, as you may decide to leave space for future installations.

If it ain't broke, don't fix it. If it's not safe ... make it that way.

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