Food-grade surface coatings for process plants and food equipment

Reduce wear, friction, and production downtime in food equipment with PVD coatings that comply with relevant EU regulations and Danish statutory orders for food contact materials.

The food industry demands high levels of operational reliability, cleanability, and documentation – and stainless-steel components in pumps, valves, filling systems, and cutting machines are frequently exposed to wear, galling, and cold welding, especially in wet environments and during cleaning. At the same time, food safety regulations restrict the use of traditional lubricants. Food-grade surface coatings are a proven solution that extends component service life, reduces friction, and supports high standards of hygiene in food production.

Specialists in surface coatings at the Danish Technological Institute develop and supply PVD-based DLC and CrN coatings for process equipment in the food industry. The coatings have documented suitability for food contact and are manufactured under ISO 9001-certified quality management with full traceability.

How can Danish Technological Institute help you?

We advise on and supply surface coatings for food processing equipment, including:

Wear protection for knives, pumps, valves, bearings, pistons, and moulding tools
Friction reduction on moving parts in process plants and filling systems
Dry-lubricating coatings for applications where lubricants must be avoided
Protection against galling and cold welding between, for example, stainless steel surfaces
Documentation for audits and customer requirements, including certificates with full traceability
Surface characterization – measurement of hardness, roughness, and coating thickness
Consulting on material selection and surface solutions for specific food applications

Why are surface coatings important in food production?

In the food industry, metal components often operate under harsh tribological conditions: wet environments, frequent cleaning with aggressive chemicals, and mechanical stress from sliding and rotating movements. When stainless steel parts operate against each other without adequate lubrication, there is a pronounced risk of galling and accelerated wear. Furthermore, many agricultural raw materials inherently contain a certain amount of mineral particles, which exert an intensely abrasive effect on the equipment.

Typical challenges include:

Wear and galling between stainless steel surfaces
Galling and cold welding on moving parts in, for example, valves and pumps
High friction in bearings, pistons, and other highly loaded components
Restrictions on lubricant usage to ensure food safety
Requirements for easy-to-clean surfaces, documentation, and traceability

A food-grade surface coating addresses these challenges comprehensively: it reduces wear and friction, mitigates the risk of component failure, and promotes hygiene and ease of cleaning - all without compromising food safety.

DLC and CrN coatings for food equipment

Danish Technological Institute offers two primary types of PVD coatings specifically suited for the food industry. The optimal choice depends on the specific application, load profile, and operating environment.

DLC coatings are carbon-based coatings featuring self-lubricating properties and low friction coefficients. They are particularly well-suited for metal parts where conventional lubrication is undesirable or insufficient – such as in aqueous environments or in direct contact with food products. Our DLC-TR and DLC-Si variants are formulated for sliding and rotating contact surfaces and can substantially reduce wear and galling.

CrN-based coatings (chromium nitride) deliver high wear resistance and robust surface protection. They are especially relevant when stainless steel components are exposed to mechanical wear and the threat of galling.

Both coating types improve the corrosion resistance of the treated surfaces, have documented suitability for food contact, and can be used with all types of food.

DLC product sheet

1,1 MB pdf

CrN product sheet

909 KB pdf

CrN-HP product sheet

1,5 MB pdf

Read more about our PVD coatings

Dry lubrication: reduce reliance on lubricants

In many food applications, the use of lubricants is either restricted or entirely prohibited – for instance, where product contamination cannot be tolerated, or where lubricated components operate in direct contact with food products. In such cases, dry-lubricating DLC coatings can replace or supplement traditional lubrication.

Dry-lubricating coatings reduce friction directly at the interface between two metal surfaces. This results in more stable operation, lower heat generation, a reduced risk of galling, and fewer maintenance shutdowns. In practice, this allows food manufacturers to achieve extended service intervals and more reliable production without increasing the risk of contamination.

Documentation, traceability, and food contact

The food industry requires strict documentation verifying that all materials intended to come into contact with food comply with applicable legislation. Danish Technological Institute certifies that our DLC and CrN coatings for food contact fulfil the requirements of:

Regulation (EC) No 1935/2004 on materials and articles intended to come into contact with food
Regulation (EC) No 2023/2006 on good manufacturing practice (GMP)
Executive Order BEK No 681 of 25/05/2020 (Danish legislation on food contact materials)
Council of Europe Resolution CM/Res(2013)9 on metals and alloys used in food contact materials

The coatings have been tested in accordance with relevant migration testing principles and are approved for use with all categories of food.

The production of surface coatings at Danish Technological Institute is certified according to ISO 9001. Every coating process is fully traceable and can be certified with documentation linked to the specific customer order. We supply the documentation necessary for audits, vendor approvals, and customer compliance requirements.

Contact us

Does your company require surface coatings with documented food contact approval, are you considering reducing the use of lubricants, or are you facing a specific wear challenge? Contact our specialists so we can identify the right solution together – we assist with technical consulting, coating selection, and compliance documentation.

Frequently asked questions about food-grade surface coatings

What is a food-grade surface coating?

A food-grade surface coating is a thin, hard layer applied to metal components with verified suitability for contact with food. The coating complies with the requirements of EU Regulation 1935/2004 and relevant Danish statutory rules, and it is tested according to migration principles to ensure that no harmful substances migrate into the food.

What is the difference between DLC and CrN coatings?

DLC coatings (Diamond-Like Carbon) are carbon-based and feature dry-lubricating properties with low friction. They are well-suited where lubricants must be avoided or cannot be supplied in sufficient quantities. CrN coatings (chromium nitride) offer high wear resistance and excellent corrosion resistance, making them ideal for stainless steel components subjected to heavy mechanical loads or abrasive wear from hard particles. Both types are available in food-grade approved versions.

Can surface coatings replace lubricants in food equipment?

In many applications, dry-lubricating DLC coatings can reduce or entirely replace the need for lubricants. This is particularly relevant in wet environments and in components where lubricant migration onto the food product cannot be accepted. The Danish Technological Institute advises on when dry lubrication is a viable, practical solution.

Which components can be coated?

Danish Technological Institute coats a wide range of components for the food industry, including knives/blades, pump parts, valve components, bearings, pistons, mixers, agitators, moulding tools, conveyor elements, and other processing and filling equipment./u>

What documentation accompanies the coating?

Every coating batch is fully traceable and can be supplied with a certificate tied to the specific customer order. The documentation certifies compliance with EU Regulation 1935/2004, Regulation 2023/2006, Danish BEK No 681 of 25/05/2020, and Council of Europe Resolution CM/Res(2013)9. Production is ISO 9001 certified.

What are galling and cold welding?

Galling and cold welding occur when two metal surfaces – such as stainless steel against stainless steel - are pressed together under relative motion and micro-weld locally. This leads to severe surface tearing, damage, and ultimately component seizure or failure. Surface coatings mitigate this risk by establishing a durable, ceramic wear barrier between the contacting surfaces.