Hammer mill screens with rasp perforation

Efficient fine grinding with extended screen life

Hammer mill screens with rasp perforation are a specialised solution designed to support fine grinding in processes that demand both efficiency and durability. The louvre-shaped holes - narrow at the entry and wider at the exit - create a grater-like surface that not only allows particles to pass through, but also contributes to the grinding process itself.

This design is ideal for applications requiring smaller hole sizes than the material thickness, improving wear resistance and extending screen life compared to standard perforation. The design also helps reduce clogging, thanks to the wider exit geometry.

Rasp milling screens are used across a wide range of industries, including:

Pet food and aquafeed production
Cereal and grain processing
Wood and biomass milling

Rasping milling screens from RMIG Solutions are available with hole sizes from 0.20 mm up to 3.00 mm, making them suitable for both fine and coarse grinding tasks. To further enhance performance in abrasive environments, our rasping screens are offered with RMIG SurfacePlus, a durable surface treatment that increases wear and corrosion resistance, or in various types of stainless steel.

Whether you're producing high-quality feed or processing tough raw materials, rasp perforation screens help you achieve finer results, with fewer maintenance interruptions and longer screen life.

Benefits

Rasp milling screens from RMIG Solutions are designed for maximum throughput and durability. Benefits include:

Rasping effect
Hole sizes smaller than material thickness (durability)
Entry hole smaller than exit holes (less clogging)
RMIG SurfacePlus treatment (for even longer lifetime)

Materials and thicknesses

Available with hole sizes 0.20-3.00 mm in various thicknesses and materials, such as:

Mild steel
Stainless steel

RMIG SurfacePlus - extreme screen durability

RMIG Solutions offers you various types of hammer mill screens with a specially hardened surface called RMIG SurfacePlus. RMIG SurfacePlus is a thermochemical treatment generating an iron nitride-oxide hard wear layer.

To you that means increased wear resistance and longer lifetime of the screens, resulting in in less downtime and more efficient production.

Features

Surface hardness min. 500 Vickers (HV0.025) and min. 10 μm
Increased wear resistance
Non-toxic surface treatment
Increased corrosion resistance (storage of screens)
Can be applied on all types of hammer mill screens

Examples of RMIG rasp perforation screens

Perforation		Pattern	Hole size (R) mm	Pitch (T) mm	Open area %	Thickness mm	Variant
PET FOOD	Rasp perforation	R)0.6Z5X2.7	0.6	5	1	0.50	Various open areas
PET FOOD	Rasp perforation	R)0.8Z5X3.3	0.8	5	1	0.50	Various open areas
PET FOOD	Rasp perforation	R)1.0Z5X3.7	1.0	5	1	0.50	Various open areas

Perforation		Hole size (R) mm	Pitch (T) mm	Open area %	Thickness mm	Variant
	Rasp perforation	0.20-1.00	Various	-	up to 1.5 mm	Various open areas
	Rasp perforation	1.00-1.50	Various	-	up to 2.0 mm	Various open areas
	Rasp perforation	1.50-2.00	Various	-	up to 1.5 mm	Various open areas