At Apex Filling Systems, We Help Manufacturers Protect Product Purity

At Apex Filling Systems, we help manufacturers package Diesel Exhaust Fluid (DEF), chemicals, lubricants, and other industrial liquids while maintaining product quality from the storage tank to the finished package.  When selecting equipment for DEF, choosing compatible product-contact materials is one of the most important decisions you'll make.

Although DEF is a relatively simple solution of high-purity urea and deionized water, it is extremely sensitive to contamination.  The wrong material inside a filling system can compromise product quality, damage customer confidence, and potentially affect SCR system performance.  That's why stainless steel has become the industry standard for DEF packaging equipment.

Why Is Stainless Steel Used for DEF Packaging?

Stainless steel is widely used throughout DEF filling systems because it is durable, corrosion-resistant, easy to clean, and compatible with Diesel Exhaust Fluid.  Properly designed stainless steel equipment helps maintain DEF purity, reduces the risk of contamination, and supports compliance with ISO 22241, the international standard governing DEF quality.

From storage tanks and transfer piping to filling nozzles and manifolds, stainless steel provides a clean, reliable product path that protects both the manufacturer and the end user.

Understanding Why DEF Purity Matters

Diesel Exhaust Fluid consists of:

• 32.5% automotive-grade urea
• 67.5% deionized water

Because DEF is manufactured to extremely tight specifications, even trace contaminants can affect product quality.

Potential contamination sources include:

• Certain metals
• Dust and dirt
• Oils and lubricants
• Mineral deposits
• Chemical residue
• Improper cleaning practices

Protecting DEF begins long before filling—it starts with selecting compatible equipment materials.

What Is ISO 22241?

ISO 22241 is the internationally recognized standard for Diesel Exhaust Fluid.

It establishes requirements for:

Product quality

Ensuring the correct concentration and purity of DEF.

Storage and handling

Protecting the product throughout manufacturing, transportation, and packaging.

Material compatibility

Using equipment materials that will not introduce contaminants into the product.

Following ISO 22241 helps manufacturers consistently produce DEF that meets customer expectations and protects SCR systems.

Why Stainless Steel Is the Preferred Material

1. Superior Corrosion Resistance

While DEF itself is not highly corrosive, prolonged exposure can affect incompatible materials.

High-quality stainless steel resists:

• Corrosion
• Oxidation
• Surface degradation

This helps maintain both equipment reliability and product purity throughout years of production.

2. Helps Maintain DEF Purity

Perhaps the greatest advantage of stainless steel is its compatibility with DEF.

Its smooth, non-reactive surface minimizes opportunities for contamination while helping preserve the fluid's chemical integrity.

At Apex Filling Systems, product-contact components are selected with compatibility and long-term reliability in mind, especially for sensitive applications like DEF.

3. Easy to Clean

Maintaining cleanliness is essential for every DEF packaging operation.

Stainless steel provides:

• Smooth surfaces
• Easy washdown capability
• Minimal residue buildup
• Simplified sanitation procedures

Routine cleaning becomes faster and more effective, reducing the risk of cross-contamination.

4. Long Equipment Life

Packaging equipment is a long-term investment.

Stainless steel offers:

• Excellent durability
• High wear resistance
• Reduced maintenance
• Long service life

While the upfront investment may be higher than alternative materials, stainless steel often delivers a lower total cost of ownership over the life of the equipment.

304 vs. 316 Stainless Steel

DEF filling systems commonly use either 304 or 316 stainless steel.

304 Stainless Steel

Frequently used for:

• Filling machines
• Product manifolds
• Conveyor frames
• Structural components

It provides excellent corrosion resistance for most DEF packaging applications.

316 Stainless Steel

Contains molybdenum, providing additional corrosion resistance in demanding production environments or applications involving aggressive cleaning procedures.

The appropriate grade depends on your specific application, operating environment, and sanitation requirements.

Stainless Steel Throughout the Entire Packaging Line

Maintaining product purity requires more than stainless steel filling nozzles.

Manufacturers should consider compatible materials throughout the entire product path, including:

Storage tanks

Protect product quality before filling begins.

Transfer piping

Prevent contamination during product movement.

Pumps

Maintain clean, consistent product flow.

Filling manifolds

Deliver accurate, repeatable fills.

Filling nozzles

Ensure precise dispensing while minimizing contamination risks.

Why Dedicated DEF Equipment Is Recommended

One of the most common mistakes manufacturers make is attempting to package DEF using equipment previously used for other products.

Even stainless steel equipment can become contaminated if residue from incompatible products remains inside the system.

Dedicated DEF packaging equipment helps eliminate contamination from:

• Chemicals
• Lubricants
• Cleaning products
• Food ingredients
• Personal care products

For manufacturers producing multiple products, dedicated equipment significantly reduces quality risks.

Common Mistakes to Avoid

When designing a DEF packaging line, avoid these common mistakes:

Using incompatible product-contact materials

Even small amounts of contamination can compromise DEF quality.

Sharing product pathways

Dedicated transfer systems provide better protection.

Overlooking routine cleaning

Proper sanitation helps maintain compliance and product integrity.

Ignoring preventive maintenance

Inspect product-contact components regularly for wear or damage.

Choosing equipment based solely on purchase price

Long-term reliability and compatibility often provide far greater value.

What Information Should You Gather Before Speaking with Apex?

To help the Apex team recommend the right DEF packaging solution, gather the following information:

• Container sizes and materials
• Fill volume requirements
• Desired production speed
• Closure style
• Storage tank configuration
• Available floor space
• Current contamination concerns
• Desired level of automation
• Future expansion plans

This information allows us to recommend equipment that supports both your current production requirements and long-term growth.

Frequently Asked Questions

Why is stainless steel recommended for DEF packaging?

Stainless steel is corrosion-resistant, easy to clean, and compatible with DEF, helping manufacturers maintain product purity and reduce contamination risks.

Does DEF require stainless steel filling equipment?

Many DEF packaging systems use 304 or 316 stainless steel for product-contact components because these materials help support product quality and ISO 22241 compliance.

Can other materials be used with DEF?

Yes. Certain plastics such as HDPE and polypropylene are also compatible with DEF.  The most appropriate materials depend on the specific application and component.

Can I use my existing filling line for DEF?

Possibly, but the equipment should be evaluated carefully for material compatibility and contamination risks.  Many manufacturers choose dedicated DEF filling lines to protect product purity.

How can Apex Filling Systems help with DEF packaging?

Apex works with manufacturers to evaluate their product, production goals, container types, and automation requirements before recommending a filling, capping, labeling, and conveying solution designed specifically for DEF applications.

Ready to Build a Reliable DEF Packaging Line?

Not sure which equipment is right for your application?

Use the Apex Equipment Fit Selector to answer a few questions about your product, containers, and production goals.  An Apex team member can review your information and help identify the best solution for your operation.

About Apex Filling Systems

Apex Filling Systems designs and manufactures liquid filling, capping, labeling, and conveying equipment for manufacturers across the food, beverage, chemical, personal care, DEF, and distilled spirits industries.  Every packaging application is unique, and our team works closely with customers to recommend equipment that fits their products, production goals, and future growth plans.

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