OVERHEAD CRANE SAFETY:
Safety Is In Your Hands
Cranes are useful and powerful tools that need to be treated with respect. Any mistake with a crane, even a small mistake, can have serious consequences, including property damage, injury or loss of life. That’s why knowing how to use the equipment properly and following established polices and procedure is so important.
That’s the purpose of this program, to illustrate the basics of crane safety, because with an overhead crane, safety is in your hands.
Topics include safe operating procedures, pre-operating inspection, proper rigging and lifting, moving and placing a load safely.
PERSONAL PROTECTIVE EQUIPMENT
- Proper attire for crane operation includes hard hat, safety glasses and gloves.
- Slings, chains and other things can be sharp or pinch and gloves will help protect your hands, but gloves should be removed before operating the pendant.
- For smooth operation, you’ll need to have a good feel of the controls.
Gloves may hinder this feel.
TRAINING & TERMINOLOGY
- Remember, when you operate a crane, you are responsible for safe operation. You must be trained and authorized before operating any type of crane.
- Next, know the capabilities and limitations of the crane; know the weight and characteristics of what you’ll be lifting; know the area in which the lift is to be performed.
- You’ll also need to be familiar with some crane-related terminology for two reasons. You’ll be able to discuss jobs with your co-workers and you’ll be able to effectively communicate to maintenance issues that need to be addressed.
- The bridge is the main structure which spans the crane’s work area. It also supports the trolley and hoists.
- The trolley is a carriage that contains the hoisting mechanism and moves from end to end on the bridge. The hoist is a mechanism used to raise or lower the load. The hoist and drum is a spool that winds or unwinds the hoist cable.
- The block is located at the end of the hoist cable with the load hook attached.
- The first step to ensure safe operation of all of these components is to perform a pre-operation inspection. This inspection should be performed at the beginning of each shift.
- First, move the crane to an area where the block will not hurt anyone or damage equipment should it happen to fail during the inspection.
- Conduct a visual walk around inspection of the crane. Check its general appearance.
- Inspect the alignment of the bridge, condition of the hoist cable, the hook and its safety latch, guards, lubrication and markings.
- Carefully check each function of the pendant control.
- Remember, the operator should be standing in the clear when all tests are performed.
- Move the bridge and trolley. Smooth? Any strange noises or indications of malfunctions or defects?
Screeching or squealing wheels may indicate a bridge that is not true.
- Raise and lower the hoist. Is everything operating smoothly?
- Check the limit switch. Remember, the limit switch is an emergency stopping device only. The limit switch should be tested with no attachments, if possible.
- Raise the block to a point just below the limit stop tripping weight. Slowly inch the block up by moving the control intermittently until the limit switch cutter weight has tripped the limit switch.
- If the hoist still moves at a point where no movement should be occurring, stop the hoist before the load block
is pulled into the hoist drum or hits the upper sheave unit.
- If at any time, you find a problem, defect or just something you think may be unsafe, don’t use the crane.
Notify your supervisor or maintenance so it can be repaired or corrected before an accident or injury occurs.
- If your company requires an inspection form, please be sure to fill it out completely and legibly.
- The proper selection and use of rigging is also important. The type of rigging used is determined by two things: the object being lifted and its weight.
- Check the load tag on the rigging to be sure it exceeds the capacity of the lift. Just like the components of the crane, all rigging should be inspected before use.
- Look for signs of wear, tear and other defects that could affect its capacity. Examples could include kinks, bird caging, cuts, fatigue, rot, aging, deterioration, holes and more.
- Inspect all sockets, chokers, handles and other connections. All defective slings must be repaired or removed from service.
PROPER SLING ATTACHMENT
- The sling should be attached to properly balance and lift the load without causing damage to it.
- Three key factors which can have a negative impact on the sling and affect its capacity include the load balance, angle and load movement.
- An unbalanced load can create a greater force on the sling than the actual weight of the load itself. The angle of the sling also reduces its capacity.
- The greater the sling angle, the less capacity. For example, a sling at a 10-degree angle may have a 5,000 pound capacity.
- The same sling at a 70-degree angle may have a reduced capacity of 1,700 pounds. Quite a difference and a difference you need to be aware of before you lift anything.
- Never tie knots in slings. It can also reduce the capacity by up to 80 percent. Never attach one sling to another sling to lengthen its capacity.
- Slings should always be attached in a manner that provides control of the load. Never place your hands between the load and the sling while it is being lifted.
- Make sure you and your co-workers are properly positioned when lifting or moving a load to avoid being struck by the load.
SAFE LIFTING OF THE LOAD
- A safe lift takes proper planning and careful execution.
- Aisle ways between equipment and stock must be a minimum three feet wide and should be kept clear so you can move freely about.
- Before a load is lifted, make sure it is within the capacity of the crane and all sling devices being used.
- Position the bridge directly over the load. Next, position the trolley over the load. The hoist line should be vertical when lifting.
- Lower the hook to a level that the sling can easily be attached with the safety clasp engaged. Never use a hammer or other means of force to attach a sling to a hook.
- After the slings are in place, slowly raise the hook until all slack has been removed from the sling and then stopped.
- A final inspection of the sling should be conducted. Make sure the sling is sitting in the center of the hook.
- Notify all co-workers in the area exposed to the lift. Always position yourself for the best view of the load as
possible without putting yourself in potential pinch points. Remember, an experienced operator is a smooth one.
- The pendant control moves the load in three directions: forward and backward, side to side and up and down.
- Avoid sudden starts and stops. This not only causes the load to swing, but places unnecessary stress on the
slings and the crane. This can lead to potential injury, property damage and increased maintenance for the crane.
- Maintain both hands on the pendant control. When you release the control button, the electric brake will automatically set.
- In order to drift into position, it is necessary to hold the device in the first position.
- Always lift the load straight up. Do not proceed to travel with the load until you have raised it to the
appropriate height to clear all potential obstacles.
MOVING & PLACING THE LOAD SAFELY
- Once again, notify all-co-workers in the area before moving the load.
- Good housekeeping procedures are important in areas where pendant-controlled cranes are used.
- The operator’s attention is focused on the load. Check your intended path before moving the load.
- Keep a firm grip on the pendant control. Even though the dead-man switches stop the flow of energy to the
bridge and trolley should the pendant slip out of your hands, the load can still drift a short distance and endanger a co-worker or equipment.
- When traveling with a load, maintain a smooth, steady pace. Anticipate your stops and slow down gradually.
- Always face the load when traveling. Be aware of the pendant control wire getting caught on other objects too.
- The more experienced an operator you are, the smoother you operate the crane. The smoother the crane is, the safer it is.
- Whenever a load is picked up, stopped or moved or swung, there is an increased force placed on the sling and crane components.
- The more rapidly or suddenly these types of actions occur, the greater the force will be, as much as three times the normal load force. Be smooth; don’t swing the load and go slowly.
- Never carry the load over co-workers. Allow them time to move out of the way.
- Place the bridge and trolley directly over the position you will set the load. Do not swing it into place.
- Slowly set the load down. Lower the hook to a height that the slings can be safely and easily removed from the hook.
STORING SLINGS & THE CRANE
- Remember to properly store all slings not being used. Do not swing or toss the pendant control out of your way when you are finished with it. Walk it back directly under the bridge.
- When the crane is not being used, it should be moved to a designated area or safely out of the way. Raise all hooks to an intermediate position. Place all controls in the off position.
- Know the capabilities and the limitations of the equipment used. Inspect the crane and slings before you use them.
- Carefully plan each lift and perform it smoothly. Avoid sudden starts and stops.
- Always place the bridge and trolley directly over the load when raising or lowering it.
- Notify all co-workers in the area when making a lift.
- Properly store the crane and rigging when not in use.
- You’ve been entrusted with a serious responsibility: yes, operating a crane, but more than that, the safety of your co-workers.
- Operating a crane is a serious business and we expect you to treat it as such. Understand and respect the potential hazards.
- Always operate your equipment professionally and safely. If you’re unsure about the safety of a particular task, stop and ask.
- Safety is in your hands.