I just received this inquiry regarding electric molding machines…
Our processes typically run over 1 minute cycles and are considering the purchase of some new molding machines. We are being told that an all-electric molding machine will still save us money in energy, is that true? Would a hybrid electric-hydraulic machine be a better investment?
There are a couple general misconception regarding the benefits of all-electric molding machines…
Misconception #1 ~ All-electric molding machines will not save you money if you have a long cycle time. The truth is… The pump runs constantly on a hydraulic machine wasting energy, and causing component wear. Electric molding machine components do not run when they are not being used saving electricity and wear during idle moments.
Misconception #2 ~ For long cycle times… hybrid machines provide virtually the same energy savings as electric molding machines; since most of the energy is consumed during screw recovery. The truth is… As with #1, the cost and wear associated with running the pump during idle times will usually outweigh the initial savings during the purchase of the machine.
I recently visited a molder who purchased both a hybrid and an all-electric molding machine to compare their performance and energy savings side by side. Both machines ran the same mold and had processes with cycle times over two minutes. He claimed that he could throw away the hybrid machine, buy another electric molding machine, and still pay for both machines in less than four years just from the energy savings. This sounds extreme… buy it demonstrates the money you can save by thinking long term.
The costs savings for long cycle times is part of the reason machine manufacturers are being pressured to build larger and larger all-electric molding machines.