Section 6: Long Radius Rubber 90 Degree Elbow

Required Information

• Pipe Call-out Size
• Thickness of Insulation

Formulas and Measurements

• This is the Center Line Radius Divide the Pipe Call-out Size by 2 and measure from the Center Line Radius towards the Apex, both vertically and horizontally, to create Points 1 & 2 and label them Set dividers at Points 1& 2 and swing an arc from the Apex to form Cut-line A Multiply the Pipe Call-out Size by Pi, divide by 2, and add 1 1/2.
• Use this measurement to mark a point on the vertical line from Cut-line A Set dividers at the Apex to this point and swing an arc to the horizontal line to form Cut-line B Cut-line C is created by drawing a 22 1/2 degree line from the Apex to the outside arc.

Procedure

1. Step 1

   Draw a 90 degree angle; from the Apex swing an arc using the Pipe Call-out Size times 1 1/2. This is the Center Line Radius

2. Step 2

   Divide the Pipe Call-out Size by 2 and measure from the Center Line Radius towards the Apex, both vertically and horizontally, to create Points 1 & 2 and label them

3. Step 3

   Set dividers at Points 1& 2 and swing an arc from the Apex to form Cut-line A

4. Step 4

   Multiply the Pipe Call-out Size by Pi, divide by 2, and add 1 1/2. Use this measurement to mark a point on the vertical line from Cut-line A

5. Step 5

   Set dividers at the Apex to this point and swing an arc to the horizontal line to form Cut-line B

6. Step 6

   Cut-line C is created by drawing a 22 1/2 degree line from the Apex to the outside arc.