Alligator shear


Alligator shear

An alligator shear is a metal-cutting shear with a hinged jaw, powered by a flywheel or hydraulic cylinder. Alligator shears are generally set up as stand-alone shears, in which each stroke is actuated by the operator, often with a foot control. They are generally used to cut pipe or other long-length scrap metal material, like angle irons or I-beams.

Operation

While there are still mechanical alligator shears in use, powered by flywheels like a mechanical power-operated press, all modern alligator shears are powered by heavy hydraulic pistons. When actuated, the piston arm extends and slowly closes the upper jaw of the alligator shear, which passes alongside the bed or lower jaw of the shear to perform the cut.

Uses

Alligator shears are used for cutting long-length metal stock or scrap, generally where accuracy is not an important consideration, and the size or shape of the material makes other cutting or shearing options impractical- often the only other cutting option is torch cutting. Alligator shears are often used in conjunction with large metal shredders in the metal recycling industry, to 'clean' or prepare scrap for shredding by removing unwanted fittings or other parts the shredder will not accept.

Guarding requirements

The safety requirements for other powered metalworking shears are contained in ANSI B11.4, but alligator shears are specifically excepted from that standard. Federal OSHA and various state OSHA programs have requirements for guarding alligator shears, and newly-manufactured alligator shears are provided with guards that adjust to the size of the stock or scrap being cut. The purpose of this guard, however, is to prevent pieces of metal from being ejected during cutting. Such a guard also prevents inadvertent exposure of the operator's hands, but does not conform to more stringent 'point of operation' guarding requirements.

In an interpretive letter dated June 24, 1981, Federal OSHA discussed the guarding dilemma presented by the alligator shear.

In instances where the shear is exclusively used for routine cuts on standardized stock, safeguarding of the point of operation is definable. In other instances, the operator is safeguarded from exposure to the point of operation by the physical size and configuration of the material being cut.

These practical considerations for guarding are not exclusive to alligator shears. A much more common type of equipment, the press brake, also requires point of operation guarding when used with standardized stock, but not with large-dimension stock.


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • alligator shear — heavy shears for cutting metal slabs. * * * …   Universalium

  • alligator shear — heavy shears for cutting metal slabs …   Useful english dictionary

  • Shearing (manufacturing) — Shearing, also known as die cutting,[1] is a process which cuts stock without the formation of chips or the use of burning or melting. Strictly speaking, if the cutting blades are straight the process is called shearing; if the cutting blades are …   Wikipedia

  • Jack the Tab - Acid Tablets Volume One — Infobox Album Name = Jack The Tab Acid Tablets Volume One Type = studio Artist = Psychic TV Released = 1989 Recorded = Genre = Length = Label = Castalia Recordings ACID 001 Producer = Reviews = Last album = This album = Next album = Jack The Tab… …   Wikipedia

  • Jack the Tab/Tekno Acid Beat — Infobox Album Name = Jack The Tab/Tekno Acid Beat Type = compilation Artist = Psychic TV Released = 1998 Recorded = Genre = Length = Label = Wax Trax! Records WAX 7127 Producer = Reviews = Last album = This album = Next album = Jack The Tab/Tekno …   Wikipedia

  • Scrap — metal redirects here. For other uses, see Scrap Metal (disambiguation). 3R Concepts Waste Disposal Hierarchy Reduce Reuse Recycle Barter Dematerialization …   Wikipedia

  • Cyclone Monica — Severe Tropical Cyclone Monica Category 5 cyclone (Australian scale) Category 5 Tropical cyclone (SSHS) Severe Tropical Cyclone Monica near peak intensity Formed 17 …   Wikipedia

  • Inventions in the modern Islamic world — [ Abdus Salam, the 1979 Nobel Prize in Physics recipient, include the electroweak interaction, electroweak symmetry breaking, magnetic photon, neutral current, preon, W and Z bosons, supergeometry, supermanifold, superspace and superfield.] This… …   Wikipedia

  • Hurricane Allison (1995) — Infobox Hurricane Name=Hurricane Allison Type=hurricane Year=1995 Basin=Atl Image location=Hurricane Allison 04 jun 1995 1313Z.jpg Formed=June 2, 1995 Dissipated=June 6, 1995 1 min winds=65 Pressure=987 Da Inflated=0 Fatalities=1 direct… …   Wikipedia

  • literature — /lit euhr euh cheuhr, choor , li treuh /, n. 1. writings in which expression and form, in connection with ideas of permanent and universal interest, are characteristic or essential features, as poetry, novels, history, biography, and essays. 2.… …   Universalium


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.