According to IPC Association Connecting Electronics Industries, the demand for printed circuit boards (PCB) and electronics manufacturing services has increased year-over-year by 39%. This surge is expected to continue well into 2018. To keep up with demand, manufacturers must develop newer, leaner production processes that result in a faster turnaround time without adding to the cost of ownership or compromising quality.
Traditionally, manufacturers used potting to encapsulate and protect electrical components. This process involves pouring liquid resin over electrical components, boards, or assemblies to insulate and protect the product against thermal shock, moisture, corrosive substances, etc.
The downside of potting is that the process involves many steps and requires a long curing period that increases the cycle time and can be conducive to shrinking, putting the electronic component at risk. Depending on the method used, potting materials and processes can also be quite expensive. For example, vacuum potting or using silicone rubber compounds.
High Pressure Molding (HPM) is the manufacturing world’s answer to many production woes. Instead of pouring liquid resin, this overmolding method injects the resin at high pressure into a metal mold. The extreme pressure presses the resin more tightly against the mold walls to create greater detail or produce parts with complex geometry. High pressure also makes this process fast, resulting in less production time and resources, a high production rate and, ultimately, a less expensive product.
But, not all products can stand up to the force of high pressure molding. PC board assemblies and other electrical parts are delicate, and require a softer molding approach that can still outperform potting, but doesn’t damage product components.
Low Pressure Molding (LPM) is an ideal overmolding method for delicate, low-volume electronics. The LPM process is similar to HPM, but uses less pressure to inject molten plastic into a mold. Because the pressure is reduced, this method requires more time than HPM, but—compared to potting—it offers a variety of benefits to help improve the cost, quality and time involved in overmolding delicate electronics like PCBs, connectors, sensors and cable assemblies.