Repair vs Replace Barrel
Should my worn barrel be repaired or replaced?
The decision to reline a barrel rather than replace it should be based on the economics of the situation. Moreover, if relining is the choice, the length of the reline should also be based on some guidelines. Our recommendations are:
“Unless a new barrel is required because of structural deficiencies in the old or because of down time constraints, we recommend relining only that portion of the barrel worn beyond OEM tolerance levels.”
We believe the full-length reline of a worn barrel is an excellent economic choice unless down time dictates otherwise. The length of the reline should follow a sample guideline, such as the following:
“Reline that portion of the barrel necessary to permit the blending of no more than a .003” step from the nominal bore diameter of the new liner to the I.D. of the worn barrel; however, in no case should the liner be less than the stroke of the machine plus two inches.”
This guideline protects from leaving an abrupt step where plastic can gather and burn or degrade. It also avoids having the valve assembly travel over a seam line in the repaired barrel.