Dies Mills Press Equipment for IR and XRF Spectroscopy

REFLEX Analytical provides a specialized selection of precision tools designed to meet the rigorous demands of IR and XRF spectroscopy sample preparation. Our product line supports solid, semi-solid, and liquid sampling workflows with equipment engineered for reliability, consistency, and precision control. From evacuable and non-evacuable pellet dies to high-tonnage lab presses, Wig-L-Bug grinding mills, and polymer film makers, each component is selected to optimize analytical performance and reproducibility in laboratory environments. Browse below to explore solutions trusted by materials scientists, chemists, and spectroscopists across research, quality control, and industrial applications.

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Guide to Dies, Mills, and Press Equipment for Spectroscopy Sample Preparation

Preparing accurate and reproducible samples is key to obtaining high-quality results in IR and XRF spectroscopy. Whether you are making KBr pellets for FTIR or homogenizing rock powders for XRF, your choice of dies, mills, and presses can make a major difference in sample quality, analytical precision, and lab efficiency.

This guide will walk you through everything you need to know about selecting the right equipment for your spectroscopy lab. You will learn how to choose the best pellet dies for XRF analysis, when to use evacuable vs. non-evacuable dies, what kind of press you need for pelletizing, and how to use grinding mills for proper sample homogenization.

Dies for Spectroscopy

Pellet dies are an essential part of the sample preparation process in both IR and XRF spectroscopy. They are used to compress powders into solid pellets suitable for analysis. Choosing the right type of die ensures the production of dense, uniform pellets with minimal moisture content and air pockets.

Best pellet dies for XRF analysis

XRF analysis typically requires very dense, uniform pellets with a smooth surface. Tungsten carbide dies are often preferred for this purpose due to their superior hardness, abrasion resistance, and ability to withstand the high pressures needed for XRF pelletizing.

FTIR analysis, on the other hand, often uses stainless steel dies for creating KBr pellets. These dies are more affordable and work well with softer materials like KBr or polymers.

Evacuable vs. non-evacuable pellet dies

Evacuable pellet dies can be connected to a vacuum pump to remove moisture and trapped air from the sample during compression. This is particularly useful when making pellets for FTIR, where air bubbles can interfere with light transmission. Non-evacuable dies are a simpler option and often used for XRF sample preparation where air content is less critical.

Tungsten carbide vs. stainless steel dies

Here is a quick comparison of the two most common die materials:

Feature Stainless steel Tungsten carbide
Maximum temperature ~200°C Up to 760°C
Abrasion resistance Moderate Excellent
Suitable for KBr, organics, soft polymers Hard minerals, abrasives
Cost More affordable Premium

How to choose the right die for your sample

  • For KBr pellets, a 13 mm University pellet die made from stainless steel with evacuable capability is an excellent choice.
  • For hard mineral samples, tungsten carbide dies are ideal due to their durability.
  • For polymer films, stainless steel dies with optional heating work well at moderate pressures.

Lab Presses

How much pressure do you need for pelletizing?

The amount of pressure you apply during pelletizing is just as important as your choice of die. The right lab press will help you achieve dense, durable pellets with consistent results.

Manual vs. automatic lab presses

Manual lab presses, such as 8-ton or 15-ton models, are an excellent choice for labs with limited budgets or lower sample volumes. Automatic lab presses, available in models up to 25 tons, are ideal for high-throughput labs that require consistent, repeatable pelletizing.

Video: 1 – 40 Ton Automatic Hydraulic Laboratory Presses



Why choose a 15-ton vs. 25-ton lab press

  • 8 to 15 tons is typically sufficient for preparing FTIR pellets.
  • 15 to 25 tons is often needed for dense, hard materials in XRF pellet preparation.

The best pellet press for spectroscopy depends on your lab’s needs. A 25-ton automatic press offers excellent versatility and consistency across a wide range of materials.

Video: 15 Ton Manual Hydraulic Press Overview



Grinding Mills and Accessories

How to homogenize samples for XRF and IR

Grinding mills are essential for achieving uniform particle size in spectroscopy sample preparation. Proper homogenization helps ensure accurate and repeatable results.

Best grinding mills for spectroscopy

The Wig-L-Bug grinding mill is one of the most popular tools for preparing spectroscopy samples. It quickly grinds powders to the fine particle size required for XRF and FTIR pelletizing.

How to use a Wig-L-Bug mill (step-by-step)

  1. Load sample powder and grinding ball into the mill cup.
  2. Grind for 30 to 60 seconds.
  3. Inspect particle size.
  4. Repeat if needed, then proceed to pelletizing.

Maintenance tips for Wig-L-Bug mills

  • Regularly replace grinding cups and balls to prevent contamination.
  • Thoroughly clean the mill between sample types.
  • Order replacement parts promptly to avoid equipment downtime.

Advanced applications for dies and presses

High-temperature pellet dies for extreme conditions

When analyzing high-melting-point samples or performing spectroscopy at elevated temperatures, high-temperature tungsten carbide dies rated up to 760°C are essential.

How to make KBr pellets for FTIR

  1. Dry KBr powder to eliminate moisture.
  2. Mix sample with dried KBr.
  3. Load into an evacuable die.
  4. Compress at 10 to 15 tons.
  5. Store pellets in a desiccator.

Annulus dies for specialized spectroscopy

Annulus dies produce thin, ring-shaped pellets that are ideal for diffuse reflectance spectroscopy or specialized transmission studies.

Frequently asked questions

What is the difference between evacuable and non-evacuable dies?

Evacuable dies allow moisture and trapped air to be removed using a vacuum, which is helpful for creating clearer FTIR pellets. Non-evacuable dies are simpler and often used for XRF analysis.

How much pressure is needed for pelletizing?

For FTIR, 8 to 15 tons is usually sufficient. For XRF, 15 to 25 tons may be required, depending on the material.

What is the best pellet die for XRF analysis?

Tungsten carbide dies are typically the best option for XRF, due to their hardness and resistance to wear when working with abrasive samples.