Grinderpedia is your source for all things horizontal grinders, recyclers, and hammer hogs. Get the low-down on industry terminology, colloquialisms, and learn the ins-and-outs of Peterson’s industry-leading machines. Grinderpedia is your source for What You Need to Know.
The Adaptive Feed Control System controls all components of the feed system to optimize output. This system monitors the grinding load and varies the speed of the feed system to keep the engine working at the top of its power curve. It automatically accelerates the feed rollers, slows when the load is high, and reverses if the engine speed drops. It even monitors the engine temperature and varies the cooling fan speed to minimize power usage and reduce fuel consumption.
Airbags are used to provide positive air pressure to hold the anvil assembly in place during the grinding process. The air pressure can be adjusted depending on the type of feed material that is being ground to cushion against impacts (similar to a suspension system on a tractor-trailer, that cushions bumps).
Peterson’s Animal Bedding Grate is designed with smaller, more precise openings, to filter a smoother finer chip, for customers who require the highest standards for their animals. The animal bedding grate is ideal for customers looking for low static, low dust, smooth bedding fibers for multiple applications in agriculture, animal care markets.
The best material to use for animal bedding is small, ground wood fiber that will not compact and allows adequate air flow.
A small opening grate ( generally < 1” ) that has thinner webbing between the openings so that the grate will have more open area to increase productivity.
The anvil is a long steel bar with beveled cutting edges and plays an integral part in the Peterson 3-stage product sizing process. Located at the top and just to the rear in the grinding chamber, the anvil is contacted by the feedstock with the help of the grinding bit. This collision fractures the feed material into smaller fragments until they are small enough to pass out of the chamber via the grate system.
The Anvil Breaker Grate is a Peterson innovation which can be used for grinding asphalt shingles or waste wood for mulch. The breaker grate has chromium steel breaker bars welded to the inside face which helps break up material more efficiently preventing unwanted spears. The abrasion resistant steel bars helps to extend the service life of this grate.
The ASG Breaker Grate is a specific type of Peterson anvil breaker grate used specifically for asphalt shingle grinding. The breaker grate has chromium steel breaker bars welded to the inside face which helps break up material more efficiently with this abrasive grinding feedstock. The abrasion resistant steel bars helps to extend the service life of this grate. These have small holes to get the desired output.
Asphalt Shingle Grinding (ASG) is produced by processing asphalt roofing shingles to a small spec, generally under 3/8” to salvage the valuable asphalt and sand. Grinding asphalt shingles is a recycling effort which diverts materials from the landfill and can reduce road building costs.
A baffled grate has steel strips welded horizontally across the backside of the grate under the hole openings. These strips help hold long wood spears within the opening so a trailing grinding bit can break the long piece of wood into smaller fragements preventing these unwanted spears from ending up in the finished pile.
The Bear Claw grinding bit utilizes carbide insert technology to create an extremely aggressive bit that is best used when grinding solid wood in a clean, contaminant free environment. The wear-resistant carbide inserts are brazed onto the forging and resemble the claws of a bear.
Biomass is fuel that is developed from organic materials, a renewable and sustainable source of energy used to create electricity or other forms of power. Biomass can be created from sources such as forest residuals, waste wood (scrap wood), crops (such as corn stover), and other organically based waste residuals.
A bit spacer is the 0.25″ steel plate that is installed between the backside of a grinding bit and the frontside of a bit holder. This spacer is there to protect the expensive bit holder from damage should an operator fail to notice when a grinding bit needs to be changed out due to excessive wear.
An overlay is a process that bonds one or more metals to a base metal via welding. In the case of a grinding bit, the steel forging is the base metal and the overlay that is applied to the forging consists of abrasion resistant weld wire and carbide particles. During application, the weld wire and forging are heated creating a weld pool. Carbide particles of various grit sizes are introduced into this weld pool which metalurgically bonds to the steel forging. When the weld cools, the carbide is locked into place within and on the surface of the weld. The carbide overlay provides the wear resistant protection needed to prolong the service life of a grinding bit.
The Chain Curtain is positioned behind the grinding chamber, but above the debris belt. As some ground material can travel thru the grates at a high velocity, the Chain Curtain is designed to slow down ground material to stop if from piercing the discharge belt.
Compost is organic matter that has been decomposed and may be made from single source material or blended for specific application performance. Green waste materials used include: garden debris, kitchen scraps, manure, or yard and lawn waste.
Nutrient rich in composition, compost acts as a natural, healthy, organic fertilizer for your plants. Compost is typically a soil additive mixed prior to planting to provide nutrients and improve soil structure, but can also be used a protective mulch layer or top dressed to planted areas.
The compression roll service mode is a safety feature unique to Peterson machines that ensures the service is done safely and effectively by raising the compression roll high enough to service the rotor, securing it, and disabling the system. This keeps service personnel safe, and maintenance quick.
Contaminated material is unwanted content in the feedstock material. Using feedstock with contaminates means a lower quality finished product containing contaminated materials. This unwanted content may including rocks, dirt, tramp metal, and plastic. All of these materials can cause problems with the finished material, such as plastic in compost.
Waste wood such as railroad ties and pallets often have unwanted metal and nails.
Contaminates may also cause additional wear to grinder machine parts.
The Discharge Belt on Peterson horizontal grinders is a cleated, single conveyor belt that moves materials, that has been passed through the grinding chamber, away from the machine into a stockpile. The discharge belt length and height determines the stockpile size before it needing to be removed or the grinder repositioned.
An Electronic Control System (ECS) a controller, programmable logic controller (PLC), or processor that controls the automatic electrical and hydraulic functions of a machine. It also controls safety systems, operating, and captures important machine data.
The optional feed chain return pans are used when the horizontal grinder is being used in an application when a perfect product is desired (when the slide gate is in the closed position) recirculating the unground material to be reduced again (or for easy cleanup). The pan I located underneath the hopper.
The area under the crush roll at the maximum working lift height. This is the area that all material must pass under and through to enter the grinding chamber. It is generally measured height by width.
A grate is a rectangular piece of steel that contains a pattern of holes which helps size feed material and allows it to pass from the grinding chamber to the discharge belt. After the holes are cut into the steel, the rectangle is bent in a radius along the horizontal axis. In a Peterson grinder, four grates are installed in the grinding chamber, one grate is installed on the anvil housing and the other three rest on grate supports.
The grate opening refers to the hole size and hole shape that is cut into a steel grate. The grate opening allows material to exit the grinding mill onto the discharge conveyor. Grate hole sizes can be as small as 5/8″ and as large as 8″ and anywhere in between. The most common hole shapes are hex, round, square, diamond, and rectangle.
Grate position refers to the order in which the grates are installed in the grinding mill. On a Peterson machine, the first grate is attached to the anvil housing and is referred to as the #1 position. The #2 position is just below the anvil housing followed by the #3 and #4 positions. The three grates that follow the #1 position all rest on a set of grate supports in the grinding mill.
With four different grate positions, grates can be mixed and matched to create different combinations depending on feedstock and finished product. With so many variables to grinding (everything from moisture content, feedstock, and even season) there are no set rules and lots of experimentation. However, when using a grate combination, generally, smaller opening grates in the top two positions for sizing followed by progressively larger opening grates to use as exhaust grates. Hole shapes are generally the same but this too can vary based on preferences.
Green Waste is fresh or biodegradable waste material including grass, leaves, plants and tree trimmings that can be diverted from landfills for recycling. Food waste is a separate subset that can be included in this group.
A machine using a hammer mill to process large (generally organic) materials into a smaller particle size with a higher value. Can be either the tub or horizontal style. Grinders are also referred to as recyclers.
All Peterson tracked machines come standard with triple grouser track shoes. Track shoes are what gives a machine the traction in mud, snow, and other soil conditions to move easily. Shoe styles range from rubber for indoor and pavement, to heavy duty for rocky ground. Different shoes perform best in different conditions.
Triple grouser track shoes are suitable for soft and hard ground while providing maneuverability. The grouser teeth (perpendicular protrusions) are shallow and spaced fairly close together as opposed to single grouser track shoes–providing more floatation above the surface. This means less ruts and washboarding.
Single and double grouser track shoes are available as an option on most tracked Peterson machines.
The hammer is the bit holder and bit assembly, which includes the bit spacer. The hammer strikes against the anvil, breaking material up.
The bit holder can be referred to as the hammer without referring to the whole assembly. A series of holders are welded to a shell rotor or secured in place by rotor pins to a pinned rotor in a predetermined pattern, each holding a grinding bit. Grinding bits are secured to the holders by bolts, washers, and lock nuts.
A hammermill is a general term referencing grinders as a mill that hammers material into small pieces. The word hammermill can be used in reference to the whole machine, or alternately, just the rotor and hammers.
Hard face refers to an abrasion resitant weld wire which is applied (welded) onto machine parts. The hard face reinforces the metal part and prevents premature wear when grinding in a highly abrasive environment.
The Heavy-Duty 8-Pass Bit is a carbide overlaybit with 8 passes of carbide protection on the forging. All four cutting edges along with two passes on the side of the forging as well as two passes on the face of the forging on either side of the bolt holes make up the 8 passes of carbide on this grinder bit.
A hex grate refers to the hole shape that is cut into the face of a grate which allows end product to pass through. A hexagonal pattern is made up of 6 sides and 6 angles which allow for efficient nesting of multiple hex shapes to maximize a grates open area. This grate is more productive because it has more cutting edges and a larger percentage of open area allowing higher productivity. The hex grate pattern makes up over 75% of all Peterson grate sales.
The Peterson High Abrasion bit utilizes a cast carbide technology for maximum service life in the most extreme applications. The entire face of the bit is embeded with abrasion resistant carbide particles and the corners of the forging are reinforced with hardface wire creating a grinding bit that will hold up when standard carbide overlay bits will not.
A High Tip Bucket is an attachment that is used on a wheel loader which allows for increased dump height i.e. for loading high sided vehicles. High Tip Buckets are ideal for loading Peterson horizontal grinders or blower trucks or trailers with mulch or compost material.
Horizontal grinders have several key advantages. Due to the horizontal feed, feedstock is not limited to the feed opening and are typically safer than tub grinders due to minimized thrown objects. Because the hammermill is not exposed, thrown objects are less likely, making horizontal grinder far safer.
In some countries, a horizontal grinder would be referred to as a high speed shredder.
The Impact Release System is a patented Peterson system that allows the ejection of contaminants from the grinding chamber to reduce or eliminate damage to the grinding chamber.
The Impact Release System opens the anvil and first grate section to eject ungrindable objects, then returns to normal operation. This results in more uptime and less costly damage from heavy contamination in the feed material.
The Parker IQAN (pronounced i-can) system is the main computer processor and control system platform used on all Peterson equipment. It monitors machine inputs and outputs while controlling machine functions. It is the primary interface for the operator to control performance and functions.
A Knife Edge Bit is a heat-treated steel forging with sharply ground cutting edges much like the blade of a knife. The sharp edges “cut” wood rather than “hammer” wood creating a “clean” wood fragment rather than a “fuzzy” wood fragment produced by a carbide overlay bit. The edges of these bits can be resharpened using a diegrinder with a diamond flapper wheel.
Land clearing generally consists of trees, limbs and roots cleared from forested or partially forested land that will be used for a new purpose including farming, commercial development, or right-of-ways. Most land clearing is near urban areas. On larger areas with access, trees may be logged for lumber or pulp chips that provide a higher value than recycling.
A special code in the machine’s IQAN control system that controls the functions of the compression roll to increase the maximum lift height and allow large unprocessed pieces into the grinding chamber.
The optional Magnetic Head Pulley is positioned at the top of the discharge belt and is designed to pull ferrous materials (such as nails) from the ground material. The ferrous metal then travels around the head pulley and is separated and falls down the metal collection chute into a container below, or onto the ground.
Peterson’s optional metal collection box is a useful containment tool to collect scrap metal (ie. Nails and other ferrous fasteners) collected by the optional cross belt magnet. This box is designed to be attached to the machine allowing the grinder to remain mobile. The metal collection box is easily emptied from a chute at the bottom of the box.
The ground material that is produced by Peterson horizontal grinders can offer more value if it is free of metal debris such as nails, bolts, and other ferrous hardware. The metal can be pulled from the debris stream with an optional cross belt magnet, or the optional magnetic head pulley and can be collected in a separate container or the metal collection box attached to the machine.
Metal recovery can provide an additional revenue stream as well.
Often made from bark, low value trees (non-merchantable stems) or wood waste, mulch can be made from a variety of materials, typically organic, but not exclusively. Organic mulches are typically a product that can decompose providing nutrients to the soil over time. Not all mulch materials are available commercially. Materials include:
Municipal Solid Waste (MSW)—more commonly known as trash or garbage—consists of everyday items we use and then throw away, such as product packaging, grass clippings, furniture, clothing, bottles, food scraps, newspapers, appliances, paint, and batteries. This comes from our homes, schools, hospitals, and businesses.
Grinding it can be a dirty business but is often a part of long term plans for many landfills and municipalities to reduce MSW volume and fill rates, wear on machinery, and help material decompose faster.
A style of rotor where the hammers are secured by large pins. Pinned rotors are best for contaminated applications, allowing faster part replacement due to damage. It also prevents the replacement of a whole rotor in the case of contaminated materials.
Poultry Litter materials that are made from ground materials using a horizontal grinder. The specifications for Poultry Bedding are very tight in moisture content, and size, and no metal is ever allowed. Peterson horizontal grinders with bedding grates are ideal for making this type material.
A rectangular grate has rectangle shaped grate openings in the grate material. This style provides very good sizing but without the decrease in productivity experienced with round openings.
A rectangular grate refers to the hole shape that is cut into the face of a grate which allows end product to pass through. A rectangle pattern made up of 4 sides with the two horizontal sides being longer than the two vertical sides. This hole shape can reduce spearing and is generally used when grinding for a finished product.
In most cases, a two-pass grinding process is more economical than a one-pass grinding process. When finished product sizing is critical for things like mulch and compost a two-pass regrind is optimal. Pregrinding material on the first pass for feedstock reduction with large-holed hex grates, and regrinding material for sizing with small-holed round grates offers faster production, lower fuel consumption, and a more consistent end product.
Peterson grinders are extremely productive and are often limited by the loading capacity. A rotating grapple can be much more productive loading a grinder or chipper compared to a fixed grapple which will speed up the overall production.
A Rotating Grapple is mounted to the arm of an excavator (or other boom-based loader) and allows the operator up to 360-degrees of rotation while loading a machine. This is very useful when loading odd sized materials (such as brushy tops) or when the loader is sitting off to the side of the machine. The operator can rotate the material to the correct feed angle to allow as seamless of feeding as possible.
Rotor Drums, also known as hammer hogs, or horizontal rotary mills. They are the mounting structure for horizontal bits that process the feedstock material into smaller pieces before further processing. Rotor drums are safely used in horizontal material Recyclers and Grinders as opposed to tub grinders which have a much higher risk factor.
A round grate refers to the hole shape that is cut into the face of a grate which allows end product to pass through. A round hole, generally limited to 2” or less opening size, produces a more consistent sized product and is used when grinding for a finished product. This style of grate provides the most consistent sizing when 1” minus or smaller product is required.
The Scrap Metal Chute is the large steel pan that hangs beneath the discharge belt. The magnetic head pulley at the top of the discharge belt holds tramp metal to the conveyor as it returns the loop. The metal releases from the belt once it’s pass the head pulley and drops onto the scrap metal chute. This helps keep metal out of the stockpile. Putting a bin below to collect metal materials will keep it separate.
Scrap Wood can be defined as pallets, lumber residuals, etc. This is usually dimensional lumber that has been damaged, or is too small to re-use. This material can be ground down into a mulch or biomass product using Peterson horizontal grinders.
A Sharp Edge Bit is a carbide overlay bit with tall, sharp cutting edges. This bit cuts through dense, woody material efficiently and with less energy than a more blunt edge bit saving fuel and increasing production.
A style of rotor where the hammers are welded onto a smooth drum surface versus pinned as with a pinned rotor. Shell or Drum rotors are best for applications with low contaminationfeedstock for longer wear. Drum rotors typically produce a more consistent end product than pinned rotors.
A pan that is located under the infeed head pulley and above the discharge belt that controls and directs any material that drops through the head pulley. When the slide gate is open the material drop directly onto the discharge belt with the processed material. When closed, it discharges the material for regrind directly beneath the grinding chamber. Combined with the feed chain return pan, and this material is carried to the end of the hopper for easier clean-up. Add the infeed tailgate and the material will attempt to recirculate.
A term used with or to describe shredders for the fact that the rotor(s) turn at low rpm (generally under 100rpm). The R+ horizontal grinder package offers a slow-speed rotor for heavy-duty applications.
A soft starter is a type of AC (Alternative Current) electric motor controller that temporarily reduces the load and torque (rotational force) on the motor during start-up, to prevent electrical current surges. This is especially important with large horsepower motors, that require a lot of power to get started. This type electric motor start-up also reduces the mechanical stress on the motor and shaft, as well as the electrodynamic stresses on the attached power cables and electrical distribution network, extending the lifespan of the control system.
Peterson electric chippers and grinders can be controlled with either soft starts of VFD (variable frequency drives). Soft starts are the most economical however they are limited to one speed and can result in high short term peak current loads. If electric energy is paid including a load factor for peak energy demand, the monthly bill may be very high because of the peak loads.
Peterson electric machines with a 100HP electric motor running a hydraulic system is controlled with a soft start(er).
An undesirable, odd sized material that pass thru the grates with minimal size reduction. Peterson machines are less likely to have spearing occurrences due to the up-turn rotor and three-stage grinding process.
The Standard 6-Pass bit is a carbide overlay bit with 6 passes of carbide protection on the forging. All four cutting edges along with two passes on either side of the forging make up the 6 passes of carbide protection on this grinder bit.
Tier IV (Tier 4), is an engine emissions standard. There are several tiers of emissions standards that large diesel engines must adhere to by certain dates.
Tier IV engines have exhaust aftertreatment systems to reduce emissions of particulate matter (soot) and nitrous compounds. This EPA mandate significantly reduces smog and other pollutants from diesel machinery.
The Tiger Tooth bit is a carbide overlay bit similar to the Sharp Edge Bit but with the cutting edge notched in the middle creating two tall carbide overlay “teeth” on either end of the forging. These “teeth” can efficiently penetrate and break apart solid wood.
A Variable Frequency Drive (VFD) also known as an adjustable-frequency drive, is a type of AC (Alternating Current) electric motor controller that adjusts the rotational speed (rpm) of the motor. Having the ability to change the motor speed allows for more control of the motor’s power delivery to the grinder rotor or chipper disc. The VFD changes the input frequency (Hz) and voltage to change the speed. An equally important feature of a VDF is that it can limit electrical demand, or spikes that a large load on the rotor or disc can create. This feature may reduce the electrical cost of operating the machine.
Peterson offers either a VFD or soft start option for the main rotor drive motors for most of electric grinders. VFDs are more expensive, and more complicated, but they allow more control over the motor’s speed and power output.
Peterson electric chippers and grinders can be controlled with either soft starts of VFD (variable frequency drives). VFD’s can provide variable speed that can be used to optimize the end product quality and production. They can also be programmed to limit peak power (typically 150%) which can help reduce the utility bill. VFD’s can cause electrical “noise”. Some Utilities will require additional conditioning filters. VFD’s also have a finite life and require added cooling in the control room.