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Hook Inspection

Load hooks on hoists in regular service should be visually inspected daily by the operator. If the hoistis used in multiple-shift operations, load hooks should be visually inspected by the operator at the start of each shift. When visual inspection indicates that a more detailed inspection is required, the followingare some recommended inspection procedures in addition to what is stated in the manual furnished by the manufacturer with the hoist. These procedures also would apply to scheduled frequent and periodic inspections.

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Wire Rope Inspection

Wire rope on hoists in regular service should be visually inspected daily by the operator. If the hoist is used in multiple-shift operations, wire rope should be visually inspected by the operator at the start of each shift. The daily inspection by the operator is for visual damage to the wire rope. Such damage includes excessive broken wires and wear, broken strands, kinks, birdcaging, or damage resulting in deformation of the wire rope structure. When visual damage is present, the operator shall report such damage to the supervisor, and shall not operate the hoist until a more detailed inspection is performed to determine that the wire rope can be used, or the wire rope is replaced. Detailed inspection procedures are outlined below. These procedures also apply to scheduled frequent and periodic inspections.

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Types of Hoists

The basic hoist has two important characteristics to define it: Lifting medium and power type. The lifting medium is either wire rope, wrapped around a drum, or load-chain, raised by a pulley with a special profile to engage the chain. The power can be provided by different means. Common means are hydraulics, electrical and air driven motors. Both the wire rope hoist and chain hoist have been in common use since the 1800s. however; Mass production of an electric hoist did not start until the early 1900s and was first adapted by Germany. A hoist can be built as one integral-package unit, designed for cost-effective purchasing and moderate use, or it can be built as a built-up custom unit, designed for durability and performance. The built-up hoist will be much more expensive, but will also be easier to repair and more durable. Package units were once regarded as being designed for light to moderate usage, but since the 60s this has changed. Built-up units are designed for heavy to severe service, but over the years that market has decreased in size since the advent of the more durable packaged hoist. A machine shop or fabricating shop will use an integral-package hoist, while a Steel Mill or NASA would use a built-up unit to meet durability, performance, and repair ability requirements. NASA has also seen a change in the use of package hoists. The NASA Astronaut training pool, for example, utilizes cranes with packaged hoists.