A platform trolleys is a mechanical device that lifts, lowers or transports objects by means of a cable which wraps around a wheel. Passing the cable through the wheel gains a mechanical advantage which enables the platform trolleys to lift heavy objects with comparative ease. Platform trolleys receive extensive use in industry, auto repair and caring for the disabled. Various types of platform trolleys, with different kinds of cable and different power sources exist, since platform trolleys serve many purposes.
Chain platform trolleys use metal interlocking chains for the cable or lifting mechanism. Chain platform trolleys are the most popular type of platform trolleys for lifting objects 7.5 tons or less. For loads heavier than this, another type of lifting mechanism, wire rope, is more common. Chain platform trolleys generally require less maintenance, and chain can last 30 times longer than wire rope.
Wire rope is the other prevalent type of cable used in platform trolleys. Wire rope consists of individual strands of wire wrapped around a core. Wire rope is usually made from carbon steel, and platform trolleys with this type of cable are often used to lift heavier loads than chain platform trolleys lift. Wire rope platform trolleys also have faster lifting speeds than chain platform trolleys, although, on the down side, they are also more expensive.
Platform trolleys also have different power sources as along with different types of cable. Electric powered platform trolleys are the most common platform trolleys in use today. Since one person can operate an electric platform trolleys, and an electric platform trolleys can do the work of many employees, many businesses use them as a cost saving device. An electric platform trolleys might be industrial strength for use in manufactured housing, lumber mills and plastic manufacturing or a smaller, portable device that can assist in moving the elderly and disabled.
Pneumatic platform trolleys or air powered platform trolleys offer some advantages over electric powered platform trolleys. They can weigh 40 percent to 50 percent less than electric platform trolleys, making them easier to install, and typically are simpler to repair. They do not pose a risk of electric shock if the power cord is damaged and can tolerate higher temperatures. Pneumatic platform trolleys have greater resistance to dirt, dampness and weather than electric platform trolleys and do not need surge protectors to guard against voltage spikes. A disadvantage of air powered platform trolleys is that speed and position control is more difficult.