Electromagnetic Casting & Transfer Pumps: What You Should Know

When your foundry needs to move molten metal, it can be challenging to determine which pump will best suit your needs. Within broad categories of pumps – including casting pumps and transfer pumps – there exists an array of pump types – including mechanical and electromagnetic pumps.

Because both transfer pumps and casting pumps can be powered by electromagnetism, many foundries have questions about the relationship between – and potential interchangeability of – the two types of pumps.

Below are some of the most common questions about transfer pumps and electromagnetic casting pumps, answered.

What Is a Transfer Pump?

“Transfer pump” is a general term used to describe any pump that transports large quantities of molten metal from one location to another.  All pumps under this umbrella have extremely high flow rates – and can often transfer hundreds of pounds of metal per second. They are most commonly used in foundries that move at least 20,000 pounds of metal per hour.

While transfer pumps may be used in a wide variety of applications, they are most commonly used to:

• Move metal from one part of a furnace to another
• Move metal from a melting furnace to a transfer ladle
• Move metal from a melting furnace to a holding furnace
• Stir molten metal inside a furnace

Transfer pumps are also sometimes used in casthouses, forges and extruders/rollers to cast large billets or sows that require high volumes of metal and aren’t intricate.

Are There Different Types of Transfer Pumps?

Yes, a variety of transfer pumps may be used in foundries. Broadly, transfer pumps can be grouped into two primary categories: mechanical and electromagnetic.

Mechanical Transfer Pumps

Mechanical transfer pumps use moving parts to transport molten metal. While these pumps are capable of moving high volumes of metal quickly – and have a relatively low sticker price – they are unreliable and have a short life.

Due to their construction, mechanical transfer pumps can be finnicky. If a chunk of metal gets stuck between the pump’s impeller and base block – a common occurrence – the pump will very likely break. This means most mechanical transfer pumps only last a few weeks, leading to costly, unplanned downtime.

Because of how often mechanical transfer pumps break down, most foundries that use them typically have around eight pumps for every one transfer station.

Electromagnetic Transfer Pumps

Like the name implies, electromagnetic transfer pumps use electromagnetism to move molten metal. While initially more expensive than their mechanical counterparts, electromagnetic transfer pumps are reliable and long-lasting.

Unlike mechanical transfer pumps, electromagnetic transfer pumps have a straight passage from inlet to discharge – which means chunks of metal that may enter the pump pass through instead of catching and breaking the pump. Because of this, the majority of electromagnetic transfer pumps last for years – and are significantly less likely to trigger unplanned downtime.

Are CMI Novacast Electromagnetic Pumps Transfer Pumps?

No, CMI Novacast does not make transfer pumps – though we do make electromagnetic (EM) pumps for aluminum foundries. CMI Novacast’s PG 300 and PG 450 EM pumps use electromagnetism to move metal – but are a “metering pump” primarily used to automate the casting process.

When foundries use an EM pump to automate casting, they enjoy a host of benefits including:

What’s the Difference Between a Transfer Pump & CMI Novacast Electromagnetic Pump?

Transfer pumps excel at moving high quantities of metal, crudely, from one part of a foundry to another. CMI Novacast’s EM pumps excel at moving smaller volumes of metal, precisely, from furnace to cast.

The decision about whether to use a “transfer pump” or a CMI Novacast EM pump ultimately comes down to:

1. Where you are transporting metal
2. The volume of metal you must move
3. The job you are trying to accomplish

If you need to deliver relatively small, metered amounts of molten metal from one location to another, a CMI Novacast EM pump is the appropriate solution. Both the PG 300 and PG 450 are programmable and repeatedly deliver exact amounts of metal. Because of this, they are an excellent solution for filling molds with consistency, precision and low (or no) turbulence.

If, instead, you need to move a high volume of molten metal from one location to another – and don’t need the process to be highly precise – a transfer pump would be a more appropriate solution. Both mechanical and electromagnetic transfer pumps can transport large quantities of metal, quickly – but are not exacting or particularly sophisticated.

Can Transfer & CMI Novacast Electromagnetic Pumps Be Used Together?

Yes, CMI Novacast EM pumps may be used in conjunction with both mechanical and electromagnetic transfer pumps. If your foundry produces a very high volume of intricate or critical parts that demand precision, you may use both pumps together.

While specific set ups vary, here’s an overview of a common workflow:

1. A transfer pump moves molten metal from a large furnace to a trough launder
2. The metal flows through the trough launder to a holding furnace, containing a CMI Novacast EM pump
3. The EM pump meters out a precise amount of metal into a mold

Automate Casting with EM Pumps

Since its founding in 1981, CMI Novacast has supplied foundries with EM pumps and related systems, including heated launders, preheat ovens and control systems, to alleviate common casting problems. Contact a CMI Novacast factory expert to learn how electromagnetic pumps can automate your casting process.

Contact us to learn more about electromagnetic pumps