Recognizing Double Seam Component Defects.
This sections deals with Double Seam Components and how to measure and recognize defects. There is instructions on how to strip or tear down a Double Seam with end cutters to expose Body Hooks and Cover Hooks. Visual inspection of these components will reveal possible defects not seen through a Seam Scope or Projector.
Stripping a Double Seam for Inspection

There are several means of seam inspection generally established by each individual or manufacturer, such...
Pressure Ridge

This should be a clearly visible impression around the inside of the can body which...
Deep Countersink

The Countersink measurement should be approximately equal to the thickness of the Seaming Chuck flange...
Cover Hook Wrinkling

A wrinkle in the cover hook which projects toward the can body hook or outward...