Scissor lifts are construction and maintenance vehicles that offer a stable work platform with adjustable elevation for extended vertical reach specifically by employing an extension mechanism composed of a criss-crossed tub or rod structure that can open and close in a manner resembling a pair of scissors to control the height of the lift. This assembly is usually attached on top of a mobile base to allow the lift to be moved around easily.
Motorized scissor lifts often allow the operator to adjust not only their height but also control their location while on top of the platform, saving time spent repositioning a ladder for work over a distributed horizontal range. Scissor lifts allow work to be performed in positions where suitably stable footing at an elevated position might be otherwise impossible to obtain, specially where a ladder will not suffice; ladders are limited in height and location by stability concerns and critically cannot provide a broader work platform for more involved work where freer horizontal motion might be required by the workman.
Scissors lifts are very versatile, high utility machines and excel at tasks that require a stable work platform with moderate vertical reach, free-standing stability and ease of horizontal repositioning. They are employed in a wide variety of construction and maintenance applications. They are use to lift heavy goods and provide workers access for cleaning and maintenance to multi tiered shelving in storage, distribution and bulk retail facilities, lifting materials in a production environment, to make repetitive maintenance tasks at elevation easier such as while replacing bulbs on multiple light poles, and to allow access to high areas for painting, construction and maintenance purposes such as utility line and box repair.
There are many different kinds of boom lifts that offer a variety of features and come in a number of different configurations.
Scissor lifts can offer various platform sizes depending on the work area required. Larger platforms offer more room for gear or movement while working or even multiple workers but might be unable to maneuver into tighter work situations. The platform can also be augmented with additional guardrails and protective structures, material carriers, tool holders and various other platform attachments and accessories.
Scissor lifts also vary in dimensions and features of their bases. Scissor lifts can be suitable for either rough surface terrain or slab environments. Scissor lifts equipped for rough terrain will generally use treaded, inflated or floatation tires for improved traction and stability in uneven environments where surface density and compressibility my vary greatly, whereas lifts equipped to work on slab surfaces will generally use unmarked solid tires to try and minimize impact to flooring.
Scissor lifts can mainly come with three types of power supply options; air, fuel and electric. Fuel powered scissor lifts can generally provider greater lift and handle larger platforms and loads but use engines that emit fumes and are thus unsuitable for indoor use. Electric scissor lifts on the other hand can be operated from a battery or direct electric power supply and are easier and considerably safer to maintain. However they are still not necessarily entirely free from emissions and might still be slightly excessive for lighter applications, which is where a pneumatic scissor lift would be a better option. These can be powered with zero emissions of fumes with canisters of compressed air or even manual hand pumps, but also driven directly by high pressure air pumps if necessary.
Scissor lifts can vary in the method by which the lift is driven and can have electric, hydraulic and pneumatic lift mechanisms. Electric scissor lifts are directly supplied power by an electric motor whereas hydraulic and pneumatic lifts use fluid compression for power transfer. Electric scissor lifts require a direct electric power source or must be powered by a fuel engine. Hydraulic scissor lifts can be driven either by electric motors or by high pressure air compressors and can provider greater lift power but the change in viscosity of hydraulic fluid oil in response to temperature can cause them to fail or underperform when operating in cold weather conditions. Pneumatic scissor lifts are driven by air compression, provided either by a hand pump, compressed air cylinder or directly by a high pressure air compressor.
Smaller scissor lifts are generally more affordable to rent and can be cheaper to operate in terms of fuel or maintenance. Howver they may lack the power reach or maneuverability required for more demanding jobs The platform size and weight is limited by the load bearing capacity of the actual lift scissor mechanism so care must be taken to use a scissor lift that can handle all the demands of a job during the planning phase.