For the Morbark M20R chipper, the grate and slat chain options are designed to tailor your chip size, optimize production rates, and match your equipment to end-user requirements (such as biomass or fuel chips).
Here’s what Morbark says on their grate page: “On average, Morbark grates have more holes than competitive grates. More holes in your grate = higher production rates, lower fuel consumption, and greater operating efficiency Combined with Morbark quality, durability, and value, our grates will help to boost your bottom line and improve your product production! Morbark grates are precision-cut and -formed for the industry-leading dependability you expect from Morbark! We offer AR400 and AR450 grates for your industrial equipment! Morbark grates are available in a wide variety of shapes, sizes, and configurations.”
Grate Options
Morbark offers heavy-duty grate systems made from highly durable, abrasion-resistant AR-450 steel.
- 4″ × 4″ Forestry Grate: This is the standard forestry configuration. It helps reduce oversize chips and reduces spares, which is critical for preventing boiler blockages.
- Custom Sizing: Grates are generally available in a wide variety of shapes, sizes, and configurations to allow you to tailor the chip size precisely to your end-user’s specifications.
Slat Chain (Infeed Drag Chain) Options
The chipper’s live floor/infeed bed typically consists of a 5′ to 6′ rigid infeed bed. It is equipped with two or more strands of heavy-duty, welded-flight slat chain that carry material efficiently into the system.
- Chain Types: The M20R utilizes either WDH-110 or WDH-120 drag chain, depending on the exact operational setup.
- Slat/Tooth Configurations: The slat chain often features specific teeth (flights) attachments to aggressively grab whole trees, brush, and long material.
- Replacement: The chains are commonly sold in 10-foot sections (including master pins). In many aftermarket applications, replacement chains are purchased without teeth and tabs are welded onto the sidebars on-site to match the chipper’s exact requirements.
How to Measure Your Grates/Screens
Morbark Grates/Screens are custom made to fit your machine. Just let them know a few measurements and they can make one for you. Most of the measurements are taken as if laying your screen on a flat surface and being viewed from the side (refer to the images below for the measurements needed).
- A) Straight Width: This is the width of screen measured straight across.
- B) Curve Width: This is the width as measured with your tape following the curve of the screen.
- C) Thickness/Gauge: How thick is the metal used on your screen or what gauge steel is it?
- D) Curve Height: This the distance measured from the bottom-most point (or the flat surface your screen is on) to highest point
- inside the curve of the screen.
- E) Screen Length: The length of your screen as seen from the top.
- F) Support Width: The width of the support structures if your grate has them.
- Flat/Straight End: Does your screen have a flat or straight part on the end or is the curve continuous from tip to tip?
- Hole Shape: Are screen holes round, rectangle, square, etc?
- Hole Size: What are the dimensions of the shape? Length and width for square, diamond or rectangle, or diameter for round or hex.
- Web Thickness: The thickness of metal between the holes
You can browse specific part replacements and assemblies through the Morbark Brand Grates page or check complete machine specifications via the Morbark M20R Forestry Drum Chipper product overview.
