Seam Bumps are a relatively short area of the double seam, up to approximately 1-1/4”, where the seam thickness suddenly increases .004” or more. They are predominately found on welded and two piece cans with long body hooks and are usually seen on the packer’s end when hot filled products exceed 185 degrees (fahrenheit). The cover hook radius may be pulled away from the body wall.

POTENTIAL CAUSES:

• Overly tight seams.

• Long body hooks.

• Inappropriate seaming roll profile.

SUGGESTED REMEDY:

• Adjust second operation seaming roll(s) to obtain 90% to 95% tightness.

• Body hook lengths should be at nominal.

• Use proper seaming roll profiles for the material being used. Contact can manufacturer for recommendation.