Anybody involved in industrial bolting will have come across the good old chalk marking on flanges so as not to miss tightening any of the fasteners. It’s a simple solution but it does have quite a few drawbacks.
- The markings can be rubbed off during the bolting operation
- If the operation stops for a period of time weather can also make them illegible
- Poor writing and changeover of shifts can cause confusion
- If there are multiple passes there may not be enough room to fit all the markings in
- Misaligned markings can cause confusion as to which bolt to tighten