Shim Calculator & Shim Sizing Guide for Pipeline

Selecting the right shim size is critical for proper pipeline alignment. This guide covers how to calculate shim thickness requirements, standard shim sizes available, and best practices for shim sizing on pipeline construction projects.

How to Calculate Shim Thickness

1. Measure the gap between pipe and support using feeler gauges or calipers
2. Account for any thermal expansion or contraction expected
3. Select the closest standard shim thickness or combination
4. If no single shim matches, create a stack of 2-3 shims
5. Verify final fit after shim placement

Standard Shim Sizes (Imperial)

• 0.001" (1 mil) — precision adjustment
• 0.002" to 0.010" — fine adjustment
• 0.015" (1/64") — light shimming
• 0.031" (1/32") — standard light shim
• 0.062" (1/16") — medium shim
• 0.125" (1/8") — heavy shim
• 0.250" (1/4") — thick shim or spacer
• 0.500" (1/2") — maximum shim, consider machined spacer beyond this

Standard Shim Sizes (Metric)

• 0.05mm to 0.25mm — precision shimming
• 0.5mm to 1.0mm — fine shimming
• 1.5mm to 3.0mm — standard shimming
• 4.0mm to 6.0mm — heavy shimming
• 8.0mm to 12.0mm — spacer range

Shim Width and Length Sizing

Shim width should match the full contact area of the pipe support. Shims that are too narrow can cause point loading and damage the pipe or support. Standard shim widths range from 2 inches to 12 inches depending on pipe diameter and support type.