Description
The socket wrench typically is of the ratchet type. The ratcheting mechanism allows the nut to be tightened or loosened with a reciprocating motion, without requiring that the wrench be removed and refitted after each turn. Typically, a small lever on the ratchet head switches the wrench between tightening and loosening mode. The sockets are attached to the ratchet through a square fitting that contains a spring-loaded ball detent mechanism to keep the sockets in place. These drive fittings come in four common sizes: 1/4 inch, 3/8 inch, 1/2 inch, and 3/4 inch (referred to as drives, as in "3/8 drive"). Despite being denominated in inches, these are international standards and no metric counterparts exist. Larger drive sizes such as 1 inch and above are usually reserved for use on fasteners of larger industrial equipment, such as tractor-trailers (articulated lorries), large cargo aircraft and passenger airliners, and marine work (merchant fleets, navies, shipyards). The sockets themselves come in a full range of inch and metric sizes. ("SAE" is often used as a blanket term for the nonmetric sizes, despite the technical inaccuracy of that usage.) The advantages of the system of a ratchet wrench with indexable sockets are speed of wrenching (it is much faster than a conventional wrench, especially in repetitive bolt-on or bolt-off usage) and efficiency of tooling cost and portability (it is much more efficient than a set of nonratcheting wrenches, with every size head having its own handle).
Read more about this topic: Socket Wrench
Famous quotes containing the word description:
“It [Egypt] has more wonders in it than any other country in the world and provides more works that defy description than any other place.”
—Herodotus (c. 484–424 B.C.)
“Everything to which we concede existence is a posit from the standpoint of a description of the theory-building process, and simultaneously real from the standpoint of the theory that is being built. Nor let us look down on the standpoint of the theory as make-believe; for we can never do better than occupy the standpoint of some theory or other, the best we can muster at the time.”
—Willard Van Orman Quine (b. 1908)
“As they are not seen on their way down the streams, it is thought by fishermen that they never return, but waste away and die, clinging to rocks and stumps of trees for an indefinite period; a tragic feature in the scenery of the river bottoms worthy to be remembered with Shakespeare’s description of the sea-floor.”
—Henry David Thoreau (1817–1862)