The lift of a large column might take an hour. Preparing for it can take months: selecting and booking the crane, preparing the ground, designing the rigging, checking the lifting lugs, planning the exclusion zone and agreeing a weather window. Get any of it wrong and the result is a delayed schedule at best and a serious incident at worst. Heavy lifting and rigging coordination for plant erection brings all of that together.
What are heavy and critical lifts?
A heavy lift involves a load that is large in weight or size relative to the lifting equipment. A critical lift is any lift where failure would have serious consequences, regardless of weight. Many companies define critical lifts using criteria such as the percentage of a crane’s rated capacity being used, lifts with two or more cranes, lifts over live equipment or occupied areas, and lifts of high-value or long-lead items. The exact thresholds come from the company’s or site’s lifting procedure.
Why heavy lifts deserve separate planning
Heavy lifts combine high consequences with long lead times. The crane may need months to book and weeks to assemble, the ground may need preparation, and the item being lifted may be irreplaceable. A lift that slips by a week can shift the erection sequence around it, so lift planning belongs on the critical path.
Lift categories
| Category | Typical examples | Planning level |
|---|---|---|
| Routine | Small loads well within crane capacity, in open areas | Standard procedure and pre-lift checks |
| Critical or engineered | Loads near crane capacity, over live plant, or with unusual rigging | Detailed lift plan, engineering review and formal approval |
| Heavy and tandem | Columns, reactors, large modules, two-crane lifts | Full engineering, ground studies, rehearsals and senior sign-off |
What a lift plan contains
- Load weight, dimensions and center of gravity, confirmed rather than assumed
- Lifting points and their certification
- Rigging arrangement: slings, shackles, spreader bars or lifting beams, with capacities
- Crane configuration, radius, boom length and capacity at each stage of the lift
- Ground bearing pressure and matting or ground preparation
- Exclusion zones and access control
- Weather and wind limits
- Communication method and signals
- Step-by-step lift sequence, including tailing for vertical items
- Contingency actions and approvals
Roles in a heavy lift
| Role | Responsibility |
|---|---|
| Lifting engineer | Designs and calculates the lift and rigging |
| Lift supervisor or appointed person | Plans and controls the lift on the day |
| Crane operator | Operates the crane within its limits |
| Riggers | Prepare and attach rigging, guide the load |
| Signaler | Directs the operator with agreed signals |
All need verified competence. Riggers and operators in particular should hold the certifications the site requires, which is part of the trade checks discussed in sourcing skilled trades for oil and gas construction.
Crane selection and logistics
Large crawler cranes need weeks to transport, assemble and test, plus space for assembly and boom laydown. Book them early and plan their positions in the erection sequence. Where several heavy lifts are planned, one large crane positioned to cover them all can be more economical than several mobilizations.
Ground preparation
A crane is only as stable as the ground beneath it. Ground studies, compacted crane pads, steel mats and checks for underground services and voids are essential, especially on reclaimed or sandy ground common in coastal Gulf sites.
Coordinating lifts with the schedule
Heavy lifts block areas for hours or days. Schedule them in the look-ahead, clear the area of other work, and coordinate with operations if lifts are near live equipment. Lifts in operating plants need the additional controls described in safety planning for work in operating facilities. The lift sequence must fit the overall plant erection plan.
Certification and documentation
Many sites require third-party inspection certificates for cranes and lifting gear, along with certified operators and riggers. Keep lift plans, certificates, inspection records and pre-lift checklists on file. After setting, the equipment moves into leveling and alignment, covered in mechanical equipment installation planning and alignment.
Apex Core Engineering supplies certified riggers, signalers and lifting supervisors through its skilled manpower supply service.
Frequently asked questions
What makes a lift critical?
Criteria vary by company, but commonly include a high percentage of rated crane capacity, tandem lifts, lifts over live equipment or occupied areas, and lifts of high-value items.
Who approves a critical lift plan?
Usually the lifting engineer and lift supervisor prepare it, and it is approved by the construction manager or a designated authority under the site’s lifting procedure.
Why is ground preparation so important for heavy lifts?
Because crane stability depends on the ground’s bearing capacity. Weak or uneven ground can cause a crane to tip under load.
Plan your heavy lifts with Apex Core Engineering.