Canning and Fish Packaging Technology

3.2.4.2.2.Seam dimensions

Unit 3 - Unit operations in canning

3.2.4.2.2.Seam dimensions (dimensions of seam and its parts)
Dimensions of properly formed seam and its parts should be within certain limits. Some of the important dimensions are

• Seam length (width) (W)
• Seam thickness (T)
• Counter sink (CS)
• Body hook (BH)
• Cover hooks (CH)
  

The first three are external dimensions and the last two are internal dimensions. The thickness of the double seam depends on the thickness of the base plate used in can manufacture. However, other dimensions such as seam width, cover hook and body hook dimension generally do not change with base plate thickness. Good quality seam should have W=0.125”, CS=0.125”, BH=0.075 to 0.085” and Minimum overlap percentage should be 45%.