Chain block
Manual chain hoists are commonly known as chain blocks and are designed for heavy duty lifting and materials handling operations. Chain blocks raise and lower loads by pulling on the hand chain. Chain blocks can be of single or double fall configurations depending on the capacity of the block.
Construction and warehouse workers use manual chain blocks to lift heavy loads manually. These pulleys, also called manual chain hoists, are capable of lifting varying weights, depending on the type and model chosen for the job. Manual chain blocks are designed with a thick steel hook at the top of a thick steel square. Wrapped around the square several times is a steel rope, which serves as the pulley chain for lifting the load. A second steel hook is attached to the end of the chain.
There are three main types of hand chain hoist available which are:
- Hook suspended which is a hoist with hooks top and bottom.
- The hoist unit fitted with a push travel trolley(manual trolley), which enables manual movement up and down a beam.
- A hoist with a geared trolley integrated in to the hoisting unit, which via the pulling of a chain drive the trolley can glide up and down a beam with the utmost ease.
We also offer a range of completely stainless steel hand chain blocks which are not presently advertised online though we will be adding them to our web site shortly.
When choosing a manual chain block model, workers must consider the size of the load they’ll be lifting. Since chain blocks are sold in different sizes, it may be advantageous to choose a size or two larger than what is needed for the immediate job. This will allow construction workers to accommodate larger loads if it becomes necessary in the future.
Inspection before use
Ensure that the chain block name plate and WLL is clearly visible and legible.
The pre-use inspection for a chain block should include the following:
Load chain
- Inspect chain for wear.
- Inspect chain for gouges, nicks, arc burns, twisted & bent links and corrosion.
- Inspect for correct reeving on multi-reeved units (3 and 5 tonne).
Lift wheels & Sheave wheels
- Inspect lift wheel for foreign material, wear and corrosion.
- Inspect dead end pins for wear, tightness and corrosion.
Hooks
- Inspect hooks for signs of opening, cracking, bending, arc burns and corrosion.
- Hooks should swivel freely.
- Inspect safety latches for condition & operation.
- Measure the hook throats for allowable service openings.
Hand chain
- Inspect chain for wear.
- Inspect chain for twisted or gouged links and corrosion.
- Inspect connecting link for signs of opening.
Miscellaneous
- Inspect frame and covers for distortion, cracks, gouges, corrosion & other damage.
- Inspect hangers (3 and 5 tonne) for cracks, gouges, corrosion & other damage.
- Inspect unit for clear WLL identity.
Crane during operation
The use of manual chain blocks calls for careful attention to safety precautions. As a general rule, warehouse workers are urged to use basic safety gear such as work boots and safety goggles when operating a manual chain block.
- The load chain must always mesh correctly with the load sheave. With multi fall chain blocks twists can arise by turning over the bottom hook through the load chain.
- Regularly lubricate the whole length of the load chain with machine or gear oil but be careful not to over lubricate as oil or grease on the brake discs can cause the brake to malfunction and slip.
- Confirm that the brake is functioning properly by hoisting the load 100mm and check the brake when lowering the load.
- Non-vertical (sideways pulling) of the hand chain is not recommended on our chain blocks.
- The hand chain is equipped with a safety link. When the safety link opens or deforms, stop at once and inspect for the cause.
- Confirm that the monorail beam or structure supporting the chain block is of sufficient strength to support the load to be lifted.
- Never lift loads in excess of the WLL of the chain block.
- Never walk or work under a hoisted load and never lift, support or transport people.
- Use chain blocks manually only.
- Do not permit more than one operator to pull on the hand chain at one time.
- Lift loads correctly with proper slings and attachments. Never lift with the point of the hook and never use the load chain as a sling by back hooking.
- Lifting a load with two chain blocks is not recommended. If the operation is unavoidable, hoist the load with utmost care, keeping the load balanced.
- Never run the load chain out too far. When operated beyond the range of lift, an excessive load that can cause damage will be imposed on the chain block.
- Chain blocks are designed for lifting loads vertically and should not be used for horizontal or angle hoisting.
- Extreme temperatures will reduce the durability of the hoist. Loads should be hoisted or lowered very slowly and carefully in extreme temperatures.
- In addition, operators should carefully inspect the chain block prior to each use.
- Workers should also inspect the hook to make certain that the hook is solidly fixed to the load before attempting to lift it.
- Most manual chain blocks are equipped with safety catches to prevent injury from chains slipping during use. If the chain block has this feature, the operator should make sure the catch is completely closed before using it. After use, workers should store the manual chain block according to the manufacturer’s instructions.
- Never leave a load hanging on the hoist.
- Never use the chain or hook as a ground for welding.
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