0.8-1.4T/H Hammer Mill for Dairy Cow Forage in the Netherlands

Why a Dutch Dairy Farm in Friesland Needed a Hammer Mill for Dairy Cow Forage

The Netherlands has the highest milk production per cow in the world, with Holsteins averaging over 9,000 kg per lactation. The farm we worked with is above average. Their cows eat a TMR of grass silage, maize silage, concentrates, and byproducts. The problem: even well-chopped forages have stem pieces that cows will sort out. The farm owner had been using a TMR mixer with a vertical auger, but cows would still leave some stem pieces in the bunk.

He looked at a German-made hammer mill offered by a dealer in Groningen. The price was €18,000 for a 45kW machine. He looked at a Belgian mill – €15,500 for a 55kW machine. He found us through a reference from a dairy in Germany. Our price, delivered to the port of Rotterdam, was €11,200 for the SFSP66*60 with 55kW motor. This included the mill, the cyclone, the fabric filter bag, and the starter screen set.

Machine Selection and Drying Process

The farmer selected the SFSP66*60 hammer mill crusher machine with a 55kW motor. The 660mm rotor diameter and 600mm crushing chamber width provide adequate capacity for his needs – about 1,500 tons of dried forage per year. Since fresh silage is too wet to grind, he built a drying shed to dry a portion of his grass silage and maize stover to 12-14% moisture.

The hammer mill for dairy cow forage in the Netherlands came with three screens. The farmer tested all three on dried grass silage (approximately 65% ryegrass, 35% clover, and some other grasses) and dried maize stover:

Dried grass silage (45% leaves and stems, 12% moisture)

• 8mm screen: Throughput of 1.4 tons per hour. Particle size: 80% between 2mm and 8mm. The cows ate most of it, but some longer grass pieces (over 10mm) remained. Waste: about 5-8%.
• 6mm screen: Throughput dropped to 1.2 tons per hour. Particle size: 85% between 1.5mm and 6mm. The cows ate everything. No visible waste. The farmer chose the 6mm screen for grass forage.
• 4mm screen: Throughput dropped to 1.0 tons per hour. More dust. Not needed.

Dried maize stover (stalks, leaves, and some cobs, 12% moisture)

• 8mm screen: Throughput of 1.2 tons per hour. Particle size: 75% between 2mm and 8mm. Some thick stalk pieces (over 10mm) remained. Waste: about 10%.
• 6mm screen: Throughput dropped to 1.0 tons per hour. Particle size: 85% between 1.5mm and 6mm. The cows ate everything. The farmer uses the 6mm screen for maize stover as well.
• 4mm screen: Throughput dropped to 0.8 tons per hour. Too slow.

The 6mm screen is the sweet spot for high-producing dairy cows. The 8mm screen leaves waste. The 4mm screen reduces throughput too much.

The mill discharges into a cyclone. The cyclone vent goes into a fabric filter bag. Dried grass and maize produce moderate dust. The bag captures about 90% of fine particles.

What the Ground Forage Is Used For

The farm produces a TMR for their high-producing Holsteins:

• 35% ground grass silage (dried, then rehydrated in the TMR – 6mm screen)
• 20% ground maize stover (dried, 6mm screen)
• 25% fresh maize silage (not ground)
• 15% concentrates
• 5% minerals and bypass protein

The farmer reported that feed waste has dropped from 10-15% to under 3%. The cows are eating more consistently, and milk production has increased by 1.2 kg per cow per day.

What the Customer Said After One Year

We spoke with the farm owner about one year after delivery. Here is what he told us:

This hammer mill for dairy cow forage has been a game-changer. The 6mm screen is perfect. Our cows eat everything now. No sorting. The bunks are clean after every feeding.

The mill runs about 4 hours per day, 5 days per week. We have put about 800 hours on it. We changed the hammers at 500 hours – flipped them to the unused side. The 6mm screen is still the original – no holes.

The drying process is the most work. We built a drying shed with a concrete floor and a plastic roof. On sunny days, the grass dries in 2-3 days. On cloudy days, it takes longer. But it is worth the effort.

Would I buy from RICHI again? Yes. The mill has improved our feed efficiency.

Logistics: Shipping from Qingdao to Rotterdam

The Netherlands' main seaport is Rotterdam. The mill was shipped from Qingdao to Rotterdam – about 35 days at sea. From Rotterdam, the customer arranged truck transport to Friesland, about 150 kilometers northeast. Total transit time was about 42 days.

Pre-sale services that built their confidence

The Dutch farmer was concerned about drying and particle size. Here is what we did:

• Material testing: He sent us 15kg of dried grass silage and 15kg of dried maize stover by air freight. We ran them through an SFSP66*60 in Qingdao using 4mm, 6mm, and 8mm screens. The 6mm screen produced the best balance. We sent him the particle size analysis and a video.
• Drying advice: We explained that fresh silage at 60-70% moisture will clog any screen. He built the drying shed based on our recommendations.
• Reference from a customer in Germany: We put him in touch with a dairy in Lower Saxony that had bought an SFSP66*60 from us for grass silage drying and grinding. They confirmed that the 6mm screen worked well for their Holsteins.
• English manual with photos: The photos helped his maintenance team.

A Note on Grinding Forage for Dairy Cows

A few practical lessons from this installation:

Drying is essential for hammer mill operation. Fresh silage or hay above 18% moisture will clog fine screens. Sun-drying or mechanical drying to 12-14% moisture is required.

The 6mm screen works well for high-producing dairy cows. The 8mm screen leaves waste. The 4mm screen reduces throughput too much.

Dried grass grinds faster than dried maize stover. Grass throughput is about 1.2 tons per hour on the 6mm screen. Maize stover is about 1.0 tons per hour.

Dust is moderate. A cyclone with a fabric filter bag is sufficient. For alfalfa or leafy grasses, a second bag helps.

Hammer wear is moderate. Maize stover has more silica than grass. The farmer got 500 hours from the first hammer set.

Global Reach of RICHI Hammer Mills

This project in the Netherlands is one example. RICHI has exported hammer mills for dairy cow forage to over 80 countries. The SFSP66*60 is a popular choice for dairy farms in Europe because it can handle the fine grind needed for high-producing cows. The 6mm screen is a standard recommendation for lactating dairy cows.

A hammer mill for dairy cow forage in the Netherlands makes economic sense for any farm with high-producing cows that need consistent, waste-free rations. The reduction in feed waste alone often pays for the mill within two years.

If You Are Grinding Forage for Dairy Cows

A few things to consider:

Drying is essential. Plan for sun-drying or a mechanical dryer. Forage over 18% moisture will clog fine screens.

What screen size do your cows need? For lactating dairy cows, 6mm works well. For dry cows, 8mm. For heifers, 6-8mm.

What is your forage type? Grass silage grinds faster than maize stover. Adjust expectations accordingly.

How will you handle the dust? A cyclone with a fabric filter bag is usually enough. For leafy forages, a second bag helps.

What is your throughput requirement? The SFSP66*60 can handle 1.0-1.4 tons per hour on a 6mm screen, depending on the forage type.

If you have high-producing dairy cows, a hammer mill for dairy cow forage with a 6mm screen can improve feed efficiency and reduce waste. Send us a sample of your dried forage. We will test it in Qingdao with different screens and send you the particle size analysis. You can see the results before you decide. RICHI Machinery has exported hammer mills for forage processing to over 80 countries worldwide.