Injection molding machines are machines that manufacture products by injecting molten material into a mold where it will cool and set. Injection molding is the most common method for producing plastic parts and is ideal for high-volume applications. Injection molding machines come in different configurations, such as the orientation (horizontal vs vertical), the material being injected (plastic, glass or otherwise), the method of fastening tools to the platens (manual, hydraulic or magnetic) and whether the machine is a hot runner or a cold runner. We have decades of accumulated experience helping manufacturers source used and surplus industrial machinery like CNC machines. Call us at (844) 262-6789 and well find the right machine for you.
Before you buy an injection molding machine for your facility, you have to understand your needs and measure them against the different configurations available to you. The difference in each component will affect which machine you ultimately buy.
Injection molding machines are classified primarily by what drive system is used to power the clamps. The more powerful a machine's drive is, the higher tonnage of clamping pressure it can exert. Presses are rated by their maximum tonnage, which can range from 9 to 90,000 tons.
Hydraulic presses are among the oldest and most common types of injection mold machines. They're not precise, but they exert a lot of force. They are readily available and are generally affordable.
Electric presses were only introduced in Japan in the last two decades, but have quickly grown in popularity as the technology improved. They are clean, efficient, and highly accurate, although all-electric presses generally don't provide as much tonnage as hydraulic systems and are more expensive.
Hybrid machines take advantage of the best features of both hydraulic and electric presses.
Plastic is delivered into the mold using two primary methods: cold running and hot running.
In a cold runner set up, a channel is carved into the mold. Molten plastic is injected through that channel into the rest of the mold. As the part cools, the plastic still within the channel cools as well and is extracted along with the part as a sprue. This process is common and relatively inexpensive, but can result in under-filled molds and sunk sections in the final product.
A hot runner system injects molten plastic directly into the cavities in the mold. They are generally faster and result in more consistent quality than a cold runner system, but are more complex and cost more as a result. This is offset by the fact that it generates less waste and runs on less time (due to the fast operation) than cold runners.
Your ideal injection molding machine depends on the level of quality and consistency you require your product to have, as well as the volume and speed of production. Initial buying cost is a factor, of course, but you should also consider operating and maintenance costs.
Call us at (844) 262-6789. Our experienced professionals will review your requirements and make sure you find the right used injection molding machine for your application.