There is an almost endless variety of resins, molds and processes available today, so there is no silver bullet that is effective against all the types of mold fouling and corrosion that attack molds, whether running or racked. An ice blasting cleaning system, however, is a very effective method. […]
P20, a 4130, 4135 modified material, has long been the steel of choice for pre-hardened mold steels. P20 is classified as a chrome-moly alloy, with a carbon content of approximately 0.30 to 0.40. Over time, many variations on basic P20 chemistry have been introduced to the marketplace. Each modification can have an effect on the [...]
The first production meeting with my new employer went something like this: “We want you to establish a PM program that is based on maximum cycle counts for all our molds.” Then, before I could launch into an explanation of how best to determine maximum cycle counts, I was hit with the follow-up: “So, how [...]
Moldmakers are always trying to identify ways to become more efficient, reduce costs, improve quality and become more diverse. In other words, how to make more money. Talk to a molder about machine processes and they think efficiency. Talk to them about productivity and they want to find out ways to fill their shop to [...]
The basis for making consistent parts for your customers is simply identifying where the physics and chemistry of plastics processing come together—inside of the mold cavity. It is in the cavity where the plastic changes from a liquid to a solid. In other words, this is where the PVT (Pressure-Volume-Temperature) properties of the plastic occur. [...]
Gas-assist technology simulates the gas-assisted injection molding process, where gas is injected into the polymer melt. Gas-assist simulation was developed about 15 years ago. In the last two years, the technology has evolved dramatically with the introduction of full 3-D analysis. […]
The evolution and revolution of technology has made mold builders more sophisticated and resourceful; and, more so now than ever before—as the trying economy and outsourcing take their toll—mold builders are seeking out value-added services and competitive advantages. Sensor technology is one such area. […]
A common challenge faced by moldmakers is to produce acceptable parts with minimum cycle time. As cooling time accounts for most of the cycle time, reducing the cooling time of a part will considerably reduce the cycle time. However, reducing the cooling time also may result in problems, such as excessive part warpage, high part [...]
Runner sizing is a very important decision for a moldmaker. In hot runners, the moldmaker may seek to minimize the runner diameters in order to reduce melt residence time, reduce color change cycles or allow tighter pitch for drops. […]
While measuring the mold can be both useful and necessary, this approach poses certain problems: […]