Powder metallurgy (PM) was first used by the ancient Egyptians 5,000 years ago in the creation of iron parts, but a lot has changed since then. Today, powder processing plants are using intelligent automation to enjoy boosted profits, attributed to more energy-efficient PM techniques.
PM describes the creation of products using fine metal powders that have been pressed to form 3D materials. The process is widely used for economic advantages, as it is an highly efficient way to use material. However, the technology is rapidly evolving and new PM methods are providing certain industries — such as automotive, machine building and manufacturing — unique advantages to production.
Due to the high precision capability of PM production, components can be created with intricate features. The good dimensional precision of this method means that manufactured parts are produced with controlled porosity and with specific properties, such as hardness and wear resistance, if required.
Despite its advantages, powder processing is complex. Forming solid parts from powdered iron, copper or ferrite, for example, creates a unique set of design considerations. Here’s where automation steps in.
The pressing motion used in PM production, requires a high level of control — particularly if parts are being manufactured to meet consistent levels of hardness. The most common machinery used for PM is die pressing. Different types of powder compaction presses are specified depending on the size of powder throughput. There are mechanical, servo-electrical and hydraulic presses available in the market, with the latter normally reserved for the biggest powder throughputs. However, most are automated.
Motor matters
One thing that is common across all automated presses is a motor. Due to the pressurized nature of this production method, and typical production rates of 15 to 30 parts pressed per minute, motors operating powder compaction presses can be under a lot of strain. It therefore makes sense to ensure these motors are running as effectively as possible.
Electric motor systems account for about 60 percent of global industrial electricity consumption, some of which will be attributed to the growing market of PM production. Of course, some of this damage can be alleviated with the implementation of variable frequency drives (VFDs), but not all manufacturers are deploying these devices.
Statistics from Siemens’ "Turn Down the Power" report estimated that the industry is overspending massively due to non-implementation of VFDs. In fact, the United States was a prime culprit, with an estimated overspend of $20.9 million between 2014 and 2019.
Fitting pressing machines with VFDs is a great start to improving efficiency, but there are also many other cost-effective measures.
Motor soft starters, or simply soft-starts, are an increasingly common way to reduce energy used when starting a motor on powder handling applications. The devices protect AC electric motors from the sudden influxes of power associated with motor startups, allowing the machine to gently ramp up power. These can act as an alternative to a motor starter resistor or a VFD.
A common challenge for PM manufacturers is the integration of this technology with existing equipment. Many factory managers may believe their legacy pressing equipment will no longer be compatible with the current VFDs or soft starts on the market. While a compatible version of the part might be obsolete, it doesn’t mean an alternative is not available. In these cases, manufacturers should get in touch with an obsolete parts supplier.
In general, obsolescence is inevitable across the factory floor, whether it affects PM systems directly or other machine parts like motors, drives and resistors. Meeting goals for energy efficiency while relying on obsolete parts requires an in-depth understanding of how existing technology can improve efficiency. This is particularly prevalent for PM manufacturers, many of which will use traditional pressing equipment.
In these instances, it is essential for any plant manager to know where spare parts can be sourced ahead of time. By working with an obsolete industrial parts supplier that knows the industry well, PM manufacturers can take a load off their minds while continuing to work toward their energy efficiency goals.
PM processing has long been hailed as a material-efficient way of manufacturing metal products. However, there are ways for these manufacturers to reap further rewards by considering how automation can boost energy efficiency of the machinery used in the manufacturing technique.
