A compactor is a machine or mechanism used to reduce the size of material such as

waste Waste (or wastes) are unwanted or unusable materials. Waste is any substance discarded after primary use, or is worthless, defective and of no use. A by-product, by contrast is a joint product of relatively minor economic value. A waste pr ...

material or bio mass through

compaction Compaction may refer to: * Soil compaction, for mechanically induced compaction near the ground surface * Compaction of ceramic powders * Compaction (geology), part of the process of lithification involving mechanical dewatering of a sediment by ...

. A trash compactor is often used by a home or business to reduce the volume of trash it produces. A baler-wrapper compactor is often used for making compact and wrapped bales in order to improve logistics. Normally powered by

hydraulics Hydraulics (from Greek: Υδραυλική) is a technology and applied science using engineering, chemistry, and other sciences involving the mechanical properties and use of liquids. At a very basic level, hydraulics is the liquid coun ...

, compactors take many shapes and sizes. In landfill sites for example, a large tractor (typically a converted front end loader with some variant of a

bulldozer blade A bulldozer or dozer (also called a crawler) is a large, motorized machine equipped with a metal blade to the front for pushing material: soil, sand, snow, rubble, or rock during construction work. It travels most commonly on continuous tracks, ...

attached) with spiked steel wheels called a landfill compactor is used to drive over waste deposited by waste collection vehicles (WCVs). WCVs themselves incorporate a compacting mechanism which is used to increase the payload of the vehicle and reduce the number of times it has to empty. This usually takes the form of hydraulically powered sliding plates which sweep out the collection hopper and compress the material into what has already been loaded. Different compactors are used in

scrap metal Scrap consists of recyclable materials, usually metals, left over from product manufacturing and consumption, such as parts of vehicles, building supplies, and surplus materials. Unlike waste, scrap has monetary value, especially recovered m ...

processing, the most familiar being the

car crusher A car crusher is an industrial device used to reduce the dimensions of derelict (depreciated) cars prior to transport for recycling. Car crushers are compactors and can be of several types: one is a "pancake", where a scrap automobile is flatte ...

. Such devices can be of either the "pancake" type, where a scrap

automobile A car or automobile is a motor vehicle with wheels. Most definitions of ''cars'' say that they run primarily on roads, seat one to eight people, have four wheels, and mainly transport people instead of goods. The year 1886 is regarded ...

is flattened by a huge descending hydraulically powered plate, or the baling press, where the automobile is compressed from several directions until it resembles a large cube.

Commercial use

Many retail and service businesses, such as fast food, restaurants, and hotels, use compactors to reduce the volume of non-recyclable waste as well as curb nuisance such as rodents and smell. In the hospitality industry tolerance for such nuisances is particularly low. These compactors typically come in electric and hydraulic operation, with quite a few loading configurations. Most popular loading configurations fall under the following: * Ground-access; * Walk-on; * Secured indoor chute. These compactors are almost exclusively of welded steel construction for two reasons: durability under pressure and exposure to the elements, as compactors are installed either completely outdoors or sometimes under a covered loading dock.

Agricultural use

As a means to preserve and store forage, baler-wrapper compactors are used to exclude oxygen from the forage and wrap it in air tight film. Without access to air the forage is preserved fresh for longer periods of time.

Residential use

In the United States, there are also trash compactors, hydraulic or manual, designed for residential use. Likewise, they reduce the volume of garbage. For example, some compactors reduce the volume of polystyrene to 1/30.

Municipal use

In the United States, in addition to the waste vehicle and landfill use, there are solar-powered trash compactors that can hold the equivalent of 200 gallons of trash before they need to be emptied. The large compactors in garbage trucks can be dangerous for workers, and played a role in the US Civil Rights Movement. The 1968 Memphis sanitation strike took place when two sanitation workers were crushed to death in garbage compactors, after which 700 of their 1300 black coworkers decided to strike.

Recycling and energy

Baler-wrapper compactors are used for efficient storage and transport of materials like RDF ( refuse-derived fuel) and bin waste, as well as compost and saw dust, enabling higher rates of recycling.

Construction industry

construction Construction is a general term meaning the art and science to form objects, systems, or organizations,"Construction" def. 1.a. 1.b. and 1.c. ''Oxford English Dictionary'' Second Edition on CD-ROM (v. 4.0) Oxford University Press 2009 and ...

, there are three main types of compactor: the plate, the rammer, and the road roller. The roller type compactors are used for compacting crushed rock as the base layer underneath concrete or stone foundations or slabs. The plate compactor, vibrating plate, or tamper, has a large vibrating baseplate and is suited for creating a level grade, while the rammer compactor has a smaller foot. The rammer, or trench rammer, is mainly used to compact the backfill in narrow

trench A trench is a type of excavation or in the ground that is generally deeper than it is wide (as opposed to a wider gully, or ditch), and narrow compared with its length (as opposed to a simple hole or pit). In geology, trenches result from ero ...

es for water or gas supply pipes etc. Road rollers may also have vibrating rollers. In plates and rollers the vibration is provided by rapidly rotating eccentric masses. In smaller plates the vibration causes a tendency to move forwards, while some larger plates are provided with a directional control. In the rammer the foot is mounted on a sleeve that slides vertically in the leg. Inside the sleeve, a piston is driven up and down by the engine through a reduction gear, crank and connecting rod. Substantial coil springs above and below the piston connect it to the sliding sleeve. The connection between the sleeve and foot is at small angle so that the whole rammer leans away from the operator. The vibrating motion is therefore slightly off the vertical, and this gives the rammer a tendency to 'walk' forwards. The sliding joint in the leg is protected by a flexible bellows. In England the name "wacker plate" or just "wacker" is commonly used to refer to plate compactors, derived from the name of Wacker Neuson, a well-known manufacturer of such devices. The name is pronounced in the English style as ''whacker'' as opposed to the correct German ''vacker''. A rammer is colloquially referred to as "

Paddy Paddy may refer to: People *Paddy (given name), a list of people with the given name or nickname *An List of ethnic slurs#P, ethnic slur for an Irishman Birds *Paddy (pigeon), a Second World War carrier pigeon *Snowy sheathbill or paddy, a bird ...

's Motorbike", due to the traditional resource of Irish construction labourers, and the way that the operator appears to "ride" the hammer holding the handles like a motorcycle. File:Plate compactor.jpg, A small plate compactor File:Zageszczarka plytowa 2.JPG, A rammer compactor File:2008-08-28 Wacker RT trench roller.jpg, A trench roller operated by remote control for operator safety File:Seabees compactor roller.jpg, Large roller "sheepsfoot" compactor for use on soil

Patents

* ' — Can crusher and baler — 1941 * ' — Compactor Service & Monitoring System — 2006

References

External links

{{Wiktionary
Preventing Injuries When Working With Ride-On Roller/Compactors
a publication from the U.S.

National Institute for Occupational Safety and Health The National Institute for Occupational Safety and Health (NIOSH, ) is the United States federal agency responsible for conducting research and making recommendations for the prevention of work-related injury and illness. NIOSH is part of the ...

Tools Engineering vehicles Waste collection