Crane lift planning is an essential component of the pre-construction process to put in another layer of safety while reducing costs and increasing efficiency of field operation. Extreme planning as well as supervision are required to avoid crane accidents. If anything goes wrong, a disaster can take place, like severe harm to property along with injury or even death. Perfect planning gives protection to cranes and persons working with or around them.
A crane is one of the most versatile types of machine working on a number of highway and other heavy construction sites. If used appropriately with a competent and trained crew, a crane is one of the most secure pieces of equipment.
When separated into various stages, the planning for a safe crane lifting plan, regardless of its complexity level, can be simplified to a great extent.
Understand Your Limits
Once you decide that you need a crane, you should first decide whether you will rent a crane or use a company-owned machine. The first and foremost factor to ponder upon should be: do you have the perfect equipment and efficient employees in-house to compose a plan and a team required to perform a safe lift? If the answer to this question is “no”, or if the answer is conditional, better you seek a third-party rental company that can provide the required planning and efficient people to carry out a secure lift for you. Importantly you should remember that hiring a third-party rental company does not lighten your share of responsibility for safety all through the lifting procedure.
In either of the cases, a single proficient person should be employed to have total responsibility and full control of the planned crane lift. A “proficient person” is an individual with thorough technical expertise, training and experience to create a safe plan of work for crane lifting procedures, so as to fulfill the requirements of the contractor.
Visiting the Site
In general it is seen that enough time is never given to visiting the site. In several cases, it is only assumed about the evaluating process for site conditions. The person in charge of developing the lifting plan must manage to visit the site to collect all the information required to ensure that the lift can be carried out from a particular position and that the ground conditions are favorable for supporting the heaviness of the crane and the materials it is going to lift. The person must also do the planning for the most favorable access and outlet to the assembly and disassembly for both – the crane and the materials. Existing closeness to dangers and any current construction work which may take place during the phase of planning should be especially focused upon while creating the lifting plan.
Once a rough drawing of the area is made and some essential details taken down, the person in charge can commence thinking about other facets of the lifting process.
Detailed documented information about the load or loads should be collected. This information must have items like:
Description: The kind of load you will be lifting – bridge deck girders, forms, precast deck panels?
Weight: Is there any idea given of the net and gross weights of load? Did you recollect to factorize in the crane load block weight, jib, hook, ball, rigging, swivel, all cables down boom point and other components?
Ingredients: Are there any hidden ingredients that could impact stability and load weight, or that could be dangerous if dropped? Is the center of gravity on the load notified?
Proximal Collision Hazards: Is there any haul road nearby? Will the superstructure of the crane be able to rotate in 360° without touching any object in its course forming a trapping point between the fixed object and the counterweight? Will you be able to assemble and disassemble the crane with crawlers or outriggers fully extended exactly as per the manufacturer’s specified requirements?
Ground Status: Is the ground whereupon the crane is to stand solid and level? Can it withstand the ground-bearing pressure that will be applied by a crawler crane or an outrigger jack with the load hanging over the corner of the outrigger or track? Does the crane pad have any hollow components under it? Will you need crane mats to even out soft ground conditions? Information about ground-bearing pressures can be collected from the crane manufacturer and supplier.
Once the crane’s loads and location are taken into consideration, the person in charge should select a crane. E.g. if you require the crane for a prolonged time and ground is too soft to operate a mobile truck crane, you may go for a crawler crane. The person in charge should have a great knowledge of cranes, specifically about:
- The strong points and limitations of each type of crane
- The way the crane works
- The safe working load of the crane from the load chart
- Crane’s weight and dimensions, both in transportation and after being set up fully
- If required, the crawler or outrigger crane track
- The person in charge should also inquire with local authorities whether there are any limitations or restrictions on operating cranes in that area
- If the crane is taken on rental basis, the certificate of crane’s annual inspection and maintenance details should be requested.
In the course of time, cranes have become increasingly complex and sophisticated. Today even an anti-collision system has been created for tower cranes. You can go through the operator’s manual, and contact the manufacturer or supplier for technology-related questions.
Choosing Right Accessories
This is as important for perfect crane lift plans as is the visit to the site, calculating load and choosing the crane. The accessories that are most commonly used include single chain slings, wire rope slings, manmade flat fiber belts, pin shackles, endless round slings, multiple leg slings and eyebolts. All the accessories should be in good shape and should not have any common, discernible defects and faults. The person in charge is responsible for choosing lifting accessories too, which should be most suitable to the procedure. This choice may taken by consulting with others and trusting the manufacturer’s guidance and instructions. While choosing the lifting accessories, you should pay special attention to:
- Working load limits or safe working loads of the accessories
- The type and quantity required
- The number of legs needed
- The suitability and compatibility of accessories with each other and their lifting points
- Most importantly, calculating the angles between accessory legs and slings
Manufacturers of lifting accessories provide a great amount of technical information about their correct usage, to the user. Much of this information is designed so as to be useful to the user; so it is simplified to make sure that the user can understand it fully for their efficient and safe use.
The person in charge should also visually examine all the accessories before using them. Such an examination can bring the commonest faults to notice that may create problems during use. Examples of these are:
- Tears and cuts
- Distortion, stretching and elongation of components and links
- Soft and hard areas on man-made slings
- Corrosion and rust
- Missing components like pins and safety catches
- Missing markings like markings of working load limits and identity numbers
Handling the Job to Others
The person in charge may in specific situations hand over tasks to an equally competent crane operator or superintendant. The crane operator or superintendant’s role is same as that of the person in charge but is more concrete: following the instructions of the person in charge instead of issuing them. The superintendant, certified signal person, qualified rigger and the crane operator’s major role is to bring the lift to a halt, if:
- S/He cannot understand what is to be done
- There are abrupt changes in the lifting operation
- S/He is doubtful about the safety of the team or lift
- The person in charge will direct the lift with the help of the crane operator, qualified rigger and certified signal person and will be responsible for attachment and detachment of lifting accessories.
Last but the most important thing that should be remembered is all people involved in crane operation should be extremely competent and should be very good as a team. Every one of them is responsible for the safety and health of others.