Since 7 years we are using both system for over molding PCB’s, connectors and cables. During this time, I have realised that many clients do not really know when and which process is the most suitable for their product.
The major difference is as mention in the title, low and high pressure.
Low pressure; (3.5 to 14 bar) and typically moderate Polyamide temperature of 210C. This technology has been invented by the automotive industry in the 70’s.
The low injection pressure does not stress a fragile solder joint by bending the PCB, or result in so called cold solder points. Therefore, it can be said, almost all electronic boards (PCB) must at least first time been over mold by low pressure. Depending on the design and requirements for our clients, we might mix the process, first over mold by low pressure to protect the PCB and the second over mold by high pressure to achieve a perfect end result.
Beside the automotive industry, this technology has spread out to other areas such as industrial products, medical, consumer products, military, wire harness and any unique product that needs to be sealed and protected against the environment such as USB thumb drives, RF ID tags, moisture sensors, motor control etc.
High pressure; (above 100 bar) with temperature up to 250C for all typically polymer material such as PVC, PU & PE. This process is faster (2-3 times) and can achieve perfect required forms due high pressure. Therefore, this technic is widely used for products for high volume and with not sensitive parts, such as USB, DSUB and others.