Coming to terms: part of learning about material handling equipment includes adding to one's vocabulary. (Material Handling Equipment Focus).

Most recycling operations have loaders, material handlers and forklifts of some type at work in the yard or plant. They typically are used to move material around, to load and unload trucks and to feed processing equipment.

Some recyclers may know a forklift from a front-end loader, but may not have much knowledge beyond that. Engineers at Bobcat Co., West Fargo, N.D., and John Deere Co., Moline, Ill., have provided these definitions of various common terms and systems. The two companies combined produce most types of mobile material handling equipment.

The following glossary is by no means comprehensive, but it can provide some help with some of the most commonly used technical terms.

ARM--Also known as the "dipper," it is the structure that connects the material handler's attachment to the boom.

ARM FORCE--Material handler's ability to produce a pulling force using the arm's hydraulic force. Also known as dipper force or crowd force.

BOOM--The primary component of the workgroup that is attached to the house structure via the swing frame. It supports the arm and attachment.

BUCKET BREAKOUT FORCE--An excavator's ability to produce a prying force using the bucket hydraulic circuit.

COMPACT EXCAVATOR--Also called a mini. Generally have operating weights less than 14,000 and dig depths less than 14 feet.

CONTROL LOCKOUT--Safety system that requires operators to place a console in "operational" position to activate hydraulics. Prevents unintended movement of components.

COUNTER WEIGHT--Weight added to the rear of the house structure to improve lifting characteristics. Also used to accommodate variations in arm configurations.

CYCLE TIME--Number of seconds that a particular function can be cycled (i.e., "boom up").

EXPANDABLE UNDERCARRIAGE--Provides a wider machine stance, allowing increased performance when working over the side of the machine. Can be retracted to allow movement in narrow spots.

EXTENDABLE ARM--Telescoping arm that increases reach for truck loading or other applications. When extra reach is not required, the dipper can be retracted to provided maximum armdigging force.

FLOTATION--Ability to traverse soils with little load-bearing capability.

GEAR PUMP SYSTEM--Oil supply mechanism that produces oil flow from rotating gear assemblies within a pump housing. It has a fixed displacement and requires changing pump shaft speed to affect pump volume.

HITCHES: Used to attach equipment for towing, especially to trucks. The three most common types of hitches are the weight-carrying hitch, the weight-distributing (or load-equalizer) hitch and the fifth-wheel hitch, or gooseneck.

* Weight-carrying hitches are designed to carry all of the trailer's tongue weight.

* Weight-distributing hitches are used with a receiver hitch and special parts that distribute the tongue weight among all tow vehicle and trailer axles.

* Fifth-wheel hitches are designed for mounting the trailer connection point in the middle of the truck bed.

HORSEPOWER (HP)--Indicated hp is mainly of interest to the engine's designer and gives the theoretical hp of an engine. Rated hp is the power an engine should be expected to produce under normal operating conditions (not necessarily the best for fuel consumption).

HYDRAULICS--Transfer power to remote drives. Fluid, under pressure, is routed through pipes or hoses and eliminates the need for universal joints and sliding couplings.

INDPENDENT BOOM SWING--Boom swing is for offset working around obstacles or along walls. Allows cycling where it's too narrow to rotate the cab.

PISTON PUMP SYSTEM--Produces oil flow from a rotating assembly of small pistons within a pump housing. Unlike gear pumps, it can vary oil flow independent of pump shaft speed.

POWER TAKE OFF (PTO)--Power train attachment that brings power from the tractor to an attachment. There are two standard PTO arrangements: 540 and 1,000 rpm. Eventually, engineers expect all PTOs will be 1,000 rpm.

REACH AT GROUND LEVEL--Measured from the material handler's center rotational axis to the tip of the standard bucket tooth at ground level.

REPOSITIONING--Moving the material handler to the next position.

SLEWING--Rotating the material handler's house assembly. Unlike conventional backhoes, an operator can slew the entire house and workgroup on the machine. Many compact excavators allow 360-degree rotation.

SPOOL METERING--Ability of the valve assembly to control oil flow to a given function in a consistent, predictable manner.

TAIL SWING--Rear overhang of the material handler as it rotates on the undercarriage.

TOPS/ROPS--TOPS is Tip Over Protective Structure. ROPS is Roll Over Protective Structure. Both protect the operator if the machine rolls or tips. To be compliant, they must be ISO or SAE certified.

VARIABLE FLOW AUXILIARY HYDRAULICS--Allows infinite control of oil flow to the auxiliary hydraulic circuit.

WEAR COMPENSATION--Mechanical means of accounting for predictable wear of mating surfaces.

360-DEGREE CAB ROTATION--Ability to continuously rotate the house. It allows better material placement, superior visibility and minimizes the fatigue on the operator.

The author is a contributing editor for Recycling Today and can be reached at [e-mail].