Abrasive Blasting Tech Tips

BlastTalk: Who's supplying your garnet?

In the previous edition, we debunked the myth that “all garnet is the same.” But as you go beyond Product Data Sheets (PDS) to find the right abrasive for your operation, there’s another side to the coin: who’s supplying that garnet.

The supplier you choose has a direct impact on your abrasive’s quality. It can also mean the difference between a consistent, predictable stock and surprises that hinder your productivity. Want to get the right garnet for your operation from a supplier you can count on? Ask these questions to ensure your supplier can deliver a consistently high-quality abrasive.

Does the supplier own the entire supply chain?

If you’ve worked with garnet abrasives in the past, you’ve already experienced some of their key benefits over slags: no toxic heavy metals, lower consumption, easier disposal, higher productivity and a lot less dust. But to reap these full benefits, you need the right supplier.

Many Indian and Chinese garnets are pooled from multiple inconsistent sources. If that variability doesn’t sound so bad right now, just wait until your operation suddenly doesn’t have the garnet it needs to get the job done—or when you open a bag only to find an abrasive that differs significantly from what you’ve been blasting with. That’s what happens when your supplier lacks sourcing controls.

Luckily, there’s a way to avoid the issue: finding a supplier that owns the entire supply chain. When you choose a supplier that handles every link from mine to customer, you’re far more likely to avoid supply interruptions and quality variants. This is critical in normal times, but it’s even more important in the COVID-era of strained supply chains and global instability.

What does “owning the entire supply chain” look like? Executing every step from mining through ongoing customer support. When you evaluate your supplier, ask about their processes at each key stage:

  • Mining: Where and how is the garnet mined?
  • Wet plant: What is the supplier’s process for separating garnet from lighter waste materials? Who executes this step, and where?
  • Quality control: Is the garnet tested in a lab setting? Which international quality standards does the supplier follow, and what internal standards are in place?
  • Dry plant: How is the garnet graded to the required size, and who performs this step?
  • Final quality control: What additional quality checks are performed before the garnet is packaged for customers?
  • Packaging and distribution: How is the garnet distributed, and what is the reach of that distributor network, both globally and in your region?
  • Customer service and technical support: What resources are available to help you select the right product and maximize its value? Does the supplier employ technical staff to help you optimize your blasting productivity?

To set yourself up for the most consistent supply, your garnet supplier should execute every step above—and be able to answer all your questions about quality controls, distribution and beyond. (Hint: It’s also worth asking what percent of the abrasive in each bag is garnet. At GMA, that number is up to 97%. Lower- quality operations could be selling you as much as 15% to 20% of trash material in each bag.)

What is the supplier’s sampling process?

Any high-quality garnet supplier will have a robust sampling process. But this is too critical to take for granted, so make sure to ask your potential supplier how their sampling protocol works. Look for evidence of well-established processes for these quality controls:

  • Percentage of ilmenite testing
  • Percentage of garnet testing
  • Conductivity
  • Tests for chloride, heavy metals, zircon/rutile and free silica
  • Particle size
  • Turbidity
  • Total acid soluble
  • XRF sample analysis
  • Magnetic separation

Once your supplier outlines its sampling process and quality controls, request third-party reports to ensure accuracy. Although this will require a bit more time on your end, that’s nothing compared to the time you could lose with a low-quality bag of abrasive—or, worse even, a supply shortage that brings your blasting operation to a standstill.

TGEAB Anthony Burns, GMA Group