Image Credit: Presto Lifts, Inc.
Lifts are work platforms used to raise and lower material, personnel and workpieces for loading and work positioning. They are widely used in construction, automotive and garage service, electrical and power service, telecommunications, manufacturing, inventory management, wire and cable industries, paining and other applications where access to above ground locations is crucial.
Types of Lifts
Lifts can be broken down into a number of specific types, based upon their platform or deck style, their mounting style, or the materials they are designed to lift. Common lift types include:
- Table lifts - Table lifts and positioners are typically used to raise and position workpieces for ergonomic access. They may also be used for material or load positioning, or lifting.
- Fork or pallet lifts - Forklifts and pallet lifts are used for lifting loads such as pallets from the floor to a raised position for working, storage height positioning, or loading and unloading. This grouping includes manual, automated, walking and motorized forklifts.
- Truck lift gates - Truck lift gates are designed for truck loading. They typically mount onto or near the back or bed of a truck, and are used for lifting loads up to or above the bed surface.
- Personnel lifts - Personnel lifts, as the name implies, are designed to raise and lower personnel to heights for working or storage activities. They generally have a lower maximum weight capacity then other types of lifts, and are usually ringed by safety devices and supports to protect those working while on them.
- Dock lifts - Dock lifts are used to raise and lower personnel and loads in loading dock areas.
Boom lifts - Boom lifts are designed for working in high places, such as ceiling welding, elevated wire installation and repair, etc.
There are a number of mechanisms by which lifts may be raised or lowered. These include:
- Scissors lifts - Scissor lifts use linked, folding support members to achieve lifts. The lifting action occurs when the members are drawn together, typically with a screw mechanism.
- Screw lifts - Screw lifts employ the mechanical advantage of threads to lift a workpiece vertically.
- Rack and pinion lifts - Rack and pinion lifts function via a small drive gear (pinion) that drives a straight-toothed rack to lift the load.
- Telescoping lifts - The telescoping lift mechanism has multiple sections that retract and extend into and out of each other.
Articulated lifts - Articulated lifts have multiple sections that unfold or articulate to lift a platform or bucket. “Cherry pickers” are frequently articulated lifts.
Lifts may be actuated by any of the following mechanisms:
- Hand cranks
- Screw drives
- Foot pumping and ratcheting
- Pneumatic air cylinders and air motors
- Hydraulic cylinders and motors
BS 5655 P3 - SPECIFICATION FOR ELECTRIC SERVICE LIFTS
BS 2655-1 - SPECIFICATION FOR LIFTS, ESCALATORS, PASSENGER CONVEYORS AND PATERNOSTERS - PART 1: GENERAL REQUIREMENTS FOR ELECTRIC HYDRAULIC AND HAND-POWERED LIFTS
MHI MH29.1 - SAFETY REQUIREMENTS FOR INDUSTRIAL SCISSORS LIFTS