Following are the typical reasons to rebuild and upgrade a transfer for most press transfer cells:
The useful life of a press transfer is considerably longer than the product life of many of the components that are used in the design of the transfer. Obtaining hardware and software support becomes difficult, putting the reliability of the transfer cell at risk.
After millions of reciprocating cycles, mechanical components wear out. This causes a loss of mechanical rigidity, destabilizing the transfer. Often the operation must be slowed to offset this lack of stability, which in turn reduces production rates.
An inspection of the transfer to determine if it can be rebuilt should include whether it can be taken out of production. The decision also should include a cost comparison of a new transfer and a rebuilt one, including the logistics associated with replacing the old transfer.
Typically, a rebuild can cost 50% to 75% of a new transfer, depending on the condition of the transfer. The price reduction results from reusing the existing framework and some of the mechanical and controls components. Normally, the main control panel is completely replaced. This new panel contains the newest platforms for PLCs, HMIs, servo drives, motion control, and communication protocols.
One possible drawback of doing a rebuild, depending on the owner’s production situation, is the time it takes to perform it. It is likely that a rebuild program will take the transfer out of production for longer than it would to buy and install a new transfer. This makes the logistical analysis an important part of the decision-making process.
There are ways to prepare for and mitigate this possibility:
- Build a part bank.
- Move production to another cell temporarily.
- Complete all the possible preparation work while the cell is operating.