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Used Injection Molding Machines

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Used Injection Molding Machines

There are constantly new techniques and new technology in the industrial world of injection molding. New machines, new plastics, new equipment. There are some companies that keep up with other companies by buying a lot of expensive equipment the second it comes out.

But these are the companies that cost so much because they have to charge more to pay for the price of the new equipment they just bought. But then you have the companies that like to keep using used machinery because they are just as good as new and as the old saying goes if it isn’t broke don’t fix it. Not every company wants to be the fancy company with all new machines.

Some companies want to just be known as the company that did my job in the most outstanding way. They want the recognition for a job well done rather than for the company who spend a lot of money on a piece of new machinery.

Companies that keep using used machinery don’t have to increase their prices and customers like to see that and they will keep coming back to the company that does great work for a great price.

Injection Molding Questions and Answers

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Here are some frequently asked questions when there are problems in the process of injection molding, here some of the most popular ones and their solutions.

What happens when the molds are brittle and delaminate? The cause may be an improper injection screw. The screw that is used for molding at a low-pressure ratio fro the amount of resin being used; causes the plastic’s molecules to form incorrectly. Basically, a weak molecular structure can cause brittle parts. When this happens de lamination can occur as well. The result will be a to take a pressure reading and record the ratio. This should be performed once every six months.

Another problem may be discoloration; the possible cause for this may be excessive dwell time or what they call residence time. When a part has been discolored or changed the problem is usually found in the residence time. The material stays in the barrel too long, the base will become discolored. What can be done is the heat sensitive materials have to be set at a certain ration. After every injection shot clean out the barrel.

Discoloration may also be caused by an improper plastic mold temp. The hotter the mold is it will keep the material melted for a longer period of time. The temp of the mold should be adjusted to the supplier’s specs on material and cycle times.