A tubular drag conveyor is a system used to transport dry bulk materials from one point to another within a space. The bulk materials are loaded into a hopper that feeds the bulk material into an enclosed tube or pipe. A chain or cable is strung within this pipe; circular load discs are attached to the chain or cable, and as the chain or cable moves, the discs will propel the dry bulk materials in one direction or another. The tubular drag conveyor eliminates the need for compressed air to transport materials.
One of the advantages of a tubular conveyor is the endless configuration possibilities. Flexible chains and cables are able to be routed around corners, up slopes, down slopes, or in circles. This is especially useful in tight processing plant settings. The tubular drag conveyor can essentially be run anywhere the pipe will fit, and many different sizes of pipe diameter are available to accommodate varying applications. The discs within the pipe will vary in size according to the size of the tube, and the size of the chain will vary accordingly as well, though the chain and cable will also vary in size according to the intended weight capacity of the tubular drag conveyor system.
The discs inside the tubular drag conveyor can be made from a variety of materials. Steel, iron, and even aluminum are common materials because they are resistant to heat damage, but some systems use synthetic materials such as plastic because of the light weight and inexpensive purchase price of such discs. The type of discs used will depend on the machine's intended applications; the materials being transported may have an effect on which materials are chosen, as can the size and layout of the entire tubular drag conveyor system. Generally, plastic discs are only suitable for lighter-duty applications, whereas steel or other metals are better suited to heavy-duty use.
While tubular drag conveyor models that feature cables are usually less expensive, chain drive conveyors are becoming more popular for added reliability. The cables can fray or otherwise become damaged over time, which means the system can break down more frequently. Using a chain instead of a cable helps reduce or eliminate this problem. Chains can also allow a user to stop or start the system under load, which is sometimes not advisable with cable driven systems because the excess force on the cable can lead it to snap or fray.