Tandem Mold Technology Trims Production Costs

A process has been developed that uses a mold with two parting levels, which alternately open. While the molding machine opens to demold one level, the other level is held together by a locking system that is recessed into the mold and is hydraulically or pneumatically controlled. Designing a mold with this locking system can result in the molder reducing production costs by up to 40 percent by almost doubling mold output and considerably reduced machine costs by eliminating the necessity for a second injection molding machine for the comparable production volume.

Developed by a Germany company called T/Mould and represented by Technoject Machinery Corp. (Bolton, ON)—a provider of injection molding solutions—
TandemMold technology is a way to integrate the tandem technique into a mold and thus make it available for normal injection molding machines. Technoject Machinery President Paul Boettger reports that the locking mechanism consists of a mechanical lock that moves to the other position after each cycle and opens/closes both parting lines simultaneously. “With longer cooling times, the cost savings over the standard technique become larger,” Boettger explains. “Thus, this technique works well with molds with large wall thicknesses and cycle times.”

Benefits

The locking system—available in a range of different sizes and designs—allows a mold to work in two parting lines in the injection molding machine. This technology offers the following advantages:

• utilized cooling time (dead time)
• increased output of up to 100 percent compared to a standard tool
• production capacity of one machine drastically increased
• optimization of each parting level individually
• can be employed in almost any injection molding machine
• improved quality due to extended cooling times
• reduction in production costs of up to 40 percent
• highly flexible
• patented brand product

Additionally, Boettger points out using a TandemMold system results in a higher output on smaller machines; and parts with different geometric configurations can be perfectly optimized. “After start-up, quality parameters and metering can be adjusted individually for each parting line,” he explains. “This is essential for family molds as the two parting lines are running independent. A simple example is the production of a bucket in one parting line and the belonging cover in the other parting line.”

As this system uses the cooling time it does not make sense to use this technology with fast running molds (e.g. cycle time three seconds), Boettger adds.

“The market always asks for ways to decrease the costs (while retaining the same quality),” Boettger concludes. “By offering TandemMolds, the moldmaker can meet this demand and help their customer to produce cheaper.”