Keep in mind that clamp maintenance should be routine and comprehensive. Once a tie bar breaks, it is critical that you ensure everything is level, parallel, lubricated, and functioning properly. If you are unsure, have an expert come in to perform a detailed analysis of your tie bars, platen movement, lubrication, bushings, and leveling.
What are the various causes of a broken Tie-Bar on a Toggle-Type Injection Molding Machine?
The tie bars are designed to last a long time, but only if ALL the following conditions are met:
• All the tie bars are parallel
• The mold travels perpendicular to the platen surface
• All the tie bars are properly level
• The machine is properly leveled and supported
• The force is applied evenly across all tie bars
• The mold is properly sized and centered
• The tonnage requirements are centered (balanced)
• The platens and tie bars do not get too hot
• Proper lubrication is applied
Below are many of the factors that cause premature tie bar failure
• Ex-centric (off-center) mold
• Mold with an off-center tonnage requirement
• Machine not level or properly supported
• Too much unsupported weight on the movable side
• Travel is not perpendicular to platen surface
• Platens not parallel
• Hot runner molds without insulator plate
• Over-clamping a mold
• Uneven mold wear
• Bent or twisted machine base
• Mold too small for the machine
• Poor initial construction
• Poor or uneven lubrication
• Excessive platen concavity
• Cracked platen
• Uneven mold bolting
• Excessive platen stoning
2 Comments Leave a comment
If the failure occurs in one of four tiebar within operation of one year.so..to avoid this
For the maintenance of tie bar in injection molding machine ,is it required for maintenance by ultrasonic examination?
Please reply as fast as possible.
It is good to inspect the tiebar stretch with ultrasonic inspection at least once a year. You should also benchmark the stretch of each tiebar with outside micrometers so you can make a quick inspection if problems arise.