The Basics of a Chain Hoist
A chain hoist, also known as a come along, is a versatile piece of lifting equipment that can be used in construction sites, auto shops, manufacturing facilities and warehouses. They can lift and suspend heavy loads in both vertical and horizontal directions.
They have a simple design and don’t require complex motors or electric systems to operate. They offer working load limits up to 20 tons and are easy to maintain.
How They Work
The most important aspect of any hoist is the mechanism that allows it to lift a chain hoist load. Most chain hoists utilize a gear system that helps to increase their maximum load capacity while decreasing the amount of effort it takes for operators to lift large objects. They also feature a number of safety features that can help to prevent any accidents or equipment damage while they are in use.
In order for a hoist to work, it must be connected to a rail or other type of track that is strong enough to support the weight of the load being lifted. The rail or track then needs to be attached to a structure that can handle the load’s size and type. This could include a ceiling mount, trolley system or some other construction that is capable of holding the weight of the load and supporting the rail or tracks attached to it.
Most electric chain hoists feature a lifting motor that provides the power for raising and lowering loads. This motor can be powered by electricity or compressed air depending on the model. The motor’s drive shaft and gears then turn a loading chain sprocket that is looped through the hoist. At the end of this load chain is a grab hook that can be used to attach slings, lifting chains and other attachments to lift or lower a load.
Types
There are many different types of chain hoists available, depending on your application. The most common types include electric and manual hoists. Electric chain hoists have the ability to lift heavier loads, can operate at a faster rate and can reach higher lifting heights. However, the motor in an electric chain hoist must be allowed to cool down between use and cannot be used continuously (also known as a duty cycle) for long periods of time.
A manual chain hoist uses a single chain that is wound around a set of gears inside the body of the hoist to lift and move the load. A chain lever or ratchet is attached to the hoist and pulled to turn the gears, which in turns causes the second load chain to be lifted or moved. These types of hoists are commonly found at construction sites, automotive repair shops, or in warehouses where heavy crates and pallets are loaded and unloaded.
If you’re looking for a hoist that can be used in an extreme environment, consider an air-powered chain hoist. These hoists can handle high-powered applications and are explosion-proof, which makes them ideal for confined spaces. Another consideration is headroom, which refers to the distance from the floor or table where you will mount the hoist to the hook when it’s at rest.
Safety
A hoist can be dangerous in the hands of an untrained operator or when it’s used with improperly rigged equipment. Fortunately, strict safety rules and proper maintenance practices have significantly reduced the number of hoist-related accidents.
Hoists and cranes must be kept free of debris, dirt and rust. These can affect their performance and even lead to failure. They also must not be exposed to contaminants, in particular acids. They should be inspected for damage, including loose or bent pins and twisted chains that can’t move freely. They should be lubricated regularly to reduce friction and ensure smooth operation. Depending on the type of hoist, it should be dismantled entirely once or twice a year for washing and lubrication.
Employees should never walk directly beneath a hoist, whether it’s powered or not. If a worker loses control of the chain hoist controls or if the chain fails, he or she could get crushed. It’s also important that other workers stay clear of a load being hoisted.
Proper training for the specific hoist is critical. It should include information about inspections and maintenance, lift capacity, braking mechanisms, slip clutches and wear limits. Training should also cover safe rigging practices, such as making sure the hoist’s hook is properly seated in the load sheave and that slings are well-balanced. Also, operators should understand the importance of a tag line.
Maintenance
One of the most important things to remember about any piece of equipment is that it must be properly maintained to ensure that it functions correctly and safely. This is especially true for equipment as powerful and dangerous as a chain hoist. Performing regular maintenance procedures can help prevent costly repairs and ensure that the device is functioning as it should.
Inspect the load chain daily for signs of wear and tear, such as stretching or nicks. Replace the chain if you notice these problems. Also, use a pair of calipers to measure the chain’s dimensions and compare them with the manufacturer’s specifications. Replace the chain if it’s excessively worn or heavily rusted.
In addition to examining the chain, you should inspect the sheave wheel and the bolts and nuts on both the sheave axle and the dead end block and clevis pin. Make sure they are tight and that there is no debris or foreign material in the sheave wheel or brake drum. Also, check that the maximum rated capacity is stenciled on the support and beam and that the warning label is attached and clearly legible.
Lastly, you should regularly clean the hoist to remove any dirt, dust, or debris that might be in the area. This can help prevent the accumulation of grit and rust that can damage parts of the system and cause it to malfunction or work improperly. You should also periodically lubricate the system’s components to ensure that they are working smoothly. A professional can recommend the right type of lubricant for your particular machine.
