I am a pipeliner and press and use a lot of carbon steel bends to accommodate the pipe line construction route. I face always a challenge when designing a single compound bend to compensate separate vertical (Over Bend) and Horizontal ( Sag Bend).
Always I need to use autocad software to prepare a demo 3d model and find out the vertical and horizontal and compound bends by trial and error method and find out which is the optimum compound bend, horizontal and vertical bend to accommodate the site condition.
It is challenging as I need to accommodate a series of consecutive cold bends ( Compound bend ) and even a mix of hot bend (5D) and cold bend (40D) combination.
To make things simple, I have attached table of Horizontal-Vertical Angles and rotation angle Data. Here in this case, the compound bend ( true bend to be pressed in the bending machine) is 30 degree. Now I need to model and check all the possible combinations to best suit to the site locations. The table is shown for rotation angle with 1 degree increment from 1 to 10 degree only. Actually I have to prepare a long table of ...say till 90 degree rotations. That is 90 combinations of rotations. Although, I get my work done, it is a very time consuming process. It is also tedious job. and more over I have atleast 200 to 300 bends to be designed and pressed as per the pipeline route.
I am doing this since 15 years of my career in pipeline construction.
The table :
Rotation of compound bend (in Degree )= first column Horizontal Bend (in Degree )= Second Column Vertical Bend (in Degree )= Third Column
0 30 0
1 29.996 0.57
2 29.985 1.154
3 29.966 1.731
4 29.94 2.306
5 29.906 2.881
6 29.864 3.454
7 29.815 4.025
8 29.758 4.594
9 29.694 5.161
10 29.622 5.725
Also attached photoshot for better understanding is the below :
1) Horizontal Angle XY Plane 2) Vertical Angle ZX Plane 3) SW View 4) Table of Horizontal-Vertical Angles and rotation angle Data
I want to know, is there any such proper formula depicting a relations between the compound angle, vertical angle, horizontal angle and rotation angle of a bend pipe ?
Lets put it more of like an example practical question. I require side cold bend of 15 degree at IP Point (Intersection Point - IP ) and also need to accommodate a vertical up bend ( sag bend ) of 6 degree. So I need to first find out a single combination bend which will fulfil my requirement. Also I need to find out the rotation angle of the compound bend to give 15 degree as side bend and 6 degree as vertical up bend.
Thanks in advance.enter image description here
