GB 50484-2019 Lifting Equipment Installation Standard Explained
GB 50484-2019, the Code for Construction of Lifting Appliances Installation Engineering, is a national mandatory standard governing the installation of lifting appliances. It specifies the installation workmanship requirements, quality acceptance criteria, and safety production requirements for various types of lifting appliances, including overhead cranes, gantry cranes, tower cranes, and mobile cranes. The code applies to the installation of lifting appliances in new, renovated, and expanded projects.
GB 50484-2019 is the national mandatory code for lifting appliance installation works, covering the full range of technical requirements from incoming inspection and crane rail installation to complete machine testing. Strict compliance with this code is the fundamental prerequisite for ensuring that cranes are safely put into operation.
Pre-Installation Preparation and Site Requirements
GB 50484-2019 sets out systematic requirements for the preparatory work before installation begins: Construction organization design — the installation contractor shall prepare a dedicated construction organization design or installation scheme covering the project overview, installation process flow chart, equipment and tool lists, personnel organization, quality requirements, and safety technical measures. The scheme shall be approved by the technical director; for medium and large cranes, the installation scheme must also undergo expert review. Foundation acceptance — the crane rail foundation or tower crane foundation shall be inspected and accepted prior to installation.
The concrete strength of the rail foundation shall reach at least 80% of the design strength, and the geometric dimensional deviations of the foundation shall comply with the following requirements: rail foundation centerline deviation ≤3mm, foundation elevation deviation ±5mm, and track gauge deviation between the two rail foundations ±5mm. For tower cranes, the foundation concrete strength must reach 100% of the design value before installation may proceed. Equipment inspection — prior to installation, all crane components shall be unpacked and inspected, verifying the accompanying documentation (Certificate of Conformity, Operation Manual, Installation Drawing) and Spare Parts List, and checking each component for transit damage, corrosion, and deformation.
Installation tools — all tools required for the lifting appliance installation, including mobile cranes, jacks, torque wrenches, spirit levels, and theodolites, shall be made available on site in advance and verified as calibrated.
Overhead and Gantry Crane Installation
The code specifies the key workmanship requirements for overhead and gantry crane installation: Crane rail installation — before laying the rails, the straightness of the rails (straightness deviation ≤2mm over any 5m length across the full span), track gauge deviation (≤±3mm, checked every 5m), and rail joint gap (≤5mm) shall be verified. The vertical difference and lateral misalignment at rail joints shall each be ≤1mm. The height difference between the two rails at the same cross-section shall be ≤5mm for spans under 30m, ≤7mm for spans between 30m and 50m, and ≤10mm for spans exceeding 50m. Main girder assembly — for overhead cranes, the camber of the main girder shall be measured before the end carriages are connected. The code requires a mid-span camber of 0.9/1000 to 1.4/1000 of the span under no-load conditions (e.g., for a 25m span, the camber shall be 22.5–35mm). Insufficient camber compromises the load-carrying stiffness of the crane. Crane travel mechanism installation — the horizontal skew of the crane bridge wheels shall be ≤0.4mm/m and the vertical skew ≤0.2mm/m. The alignment difference between the two wheels on the same end carriage shall be ≤2mm. Electrical installation — the installation of conductor rails or cable reels shall comply with the design requirements. The current collectors shall maintain good contact with the conductor rails, and the straightness deviation of the conductor rails over their full length shall be ≤3mm.
Kelude Heavy Industry provides installation guidance services for overhead and gantry cranes, ensuring that installation quality meets the acceptance standards of GB 50484.
Tower Crane Installation and Commissioning
The code specifies the following requirements for tower crane installation: Foundation construction — the tower crane foundation may be a concrete isolated foundation or a cross-shaped foundation (constructed in accordance with the Operation Manual or design requirements). The position deviation of the embedded anchor bolts shall be ≤2mm, and the levelness deviation of the foundation surface shall be ≤1/1000. Foundation settlement observation after installation — observations shall be taken daily for the first week after installation, then weekly until settlement stabilizes (defined as settlement ≤2mm over two consecutive weeks). Tower mast installation — the pre-tightening torque of the connection bolts for each mast section shall comply with the Operation Manual (typically approximately 1200N·m for M30 bolts and 2000N·m for M36 bolts). Bolts shall be tightened symmetrically in two passes (50% preload on the first pass, 100% on the final pass).
The verticality deviation of the tower mast shall not exceed 4/1000 of the total tower height in the free-standing configuration, or 2/1000 in the tied-in configuration. Jib installation — the jib shall be assembled on the ground and lifted as a complete unit. The lateral deflection of the boom shall not exceed 1/1000 of the jib length. Counterweight installation — the weight and quantity of the counterweights shall comply with the Operation Manual and shall not be altered arbitrarily.
Safety device commissioning — after installation is complete, each safety device shall be commissioned and verified individually: the load moment limiter (LML), load limiter, radius limit switch, height limit switch, slewing limit switch, and anemometer, ensuring that all protective functions operate accurately and reliably.
Quality Acceptance and Testing Procedures
The code specifies the following installation quality acceptance and testing requirements: No-Load Test — the first test performed after installation is the no-load test. Each mechanism (hoisting, travel, slewing, and luffing) shall be operated at low, medium, and high speeds for no less than 10 minutes each, verifying smooth operation of the mechanisms, reliable braking action, and proper functioning of the electrical system. Static Load Test — a load equal to 1.25 times the rated load shall be lifted at mid-span (or at the most unfavorable working radius for tower cranes), raised 100–200mm above the ground, and held stationary for 10 minutes while the deformation of the main girder (or tower mast) is observed. After unloading, the structure shall be checked for permanent deformation and structural damage.
Dynamic Load Test — a load equal to 1.1 times the rated load shall be lifted, and all mechanisms shall be operated in combination for no fewer than 3 complete cycles, verifying the reliability of the brakes, limit switches, and safety devices. During the test, no component of the crane shall exhibit cracks, permanent deformation, loosening of connections, or abnormal noise. Acceptance documentation — upon completion of the installation acceptance, an Installation Acceptance Report shall be issued, including the installation process records, precision measurement data, safety device commissioning records, and Test Report.
| Test Item | Load Coefficient | test method | Acceptance Standard |
|---|---|---|---|
| No-Load Test | 0%rated load | Full-range operation of all mechanisms≥10min | Steady operation without Abnormal noise |
| Static load test | 1.25multiples of rated load | Off-ground100mm Hovering10min | Nopermanent deformation No Crack |
| Dynamic Load Test | 1.1multiples of rated load | Combined cycle≥3Times | reliable braking No abnormality |
| safety device Commissioning | Eachrated capacity | Item-by-item trigger verification | Accurate actuation without malfunction |
Frequently Asked Questions
Q: What is the relationship between GB 50484-2019 and GB 50278-2010?
A: GB 50484-2019 is a mandatory national code governing the installation of lifting appliances, while GB 50278-2010 is the Acceptance Specification for Lifting Equipment Installation Works. The two differ fundamentally: GB 50484 is a compulsory engineering code (all clauses are enforceable) with a broader scope of application—covering installation and construction of all types of lifting appliances. GB 50278, by contrast, is a recommended acceptance specification focused on installation accuracy and acceptance standards. In practice, both codes are used in conjunction: construction work follows GB 50484, while installation accuracy acceptance references GB 50278.
Q: What preparations are required before crane installation?
A: The standard specifies the following pre-installation preparations: 1) Prepare a dedicated construction plan signed off by both the contractor's technical manager and the supervising engineer; 2) Perform incoming inspection of equipment and components, verifying model numbers, specifications, and accompanying documentation; 3) Inspect and accept the rail foundation or traveling foundation—concrete strength must reach at least 75% of the design value before equipment installation may proceed; 4) Verify the safety condition of installation tools and rigging, with all slings maintaining a safety factor of no less than 5; 5) Conduct a pre-work safety briefing for all installation personnel. Each preparation step must be documented in writing.
Q: What are the permissible deviations for crane rail installation?
A: The standard specifies the following permissible deviations for rail installation: longitudinal straightness—deviation ≤ ±3 mm per 10 m of measured length, and ≤ ±10 mm over the full rail length; lateral levelness—inclination of each rail top surface relative to the horizontal plane ≤ 1/1000; track gauge deviation—≤ ±5 mm for spans up to 30 m, and ≤ ±7 mm for spans exceeding 30 m; at rail joints, vertical misalignment ≤ 1 mm and lateral offset ≤ 1 mm; rail joint gap (thermal expansion gap)—4 to 6 mm in winter and 6 to 8 mm in summer. These deviation limits directly affect crane operating stability and the service life of the wheel blocks.
Q: What tests must be completed before the crane can be put into operation?
A: The standard requires the following tests to be performed sequentially after installation: 1) No-load test—each mechanism operates under no-load conditions for no less than 30 minutes to verify operating stability, brake response, and limit switch functionality; 2) Rated load test—lift the rated load and perform hoisting, traveling, and slewing operations while measuring deformation of primary load-bearing structural components; 3) Static load test—apply 1.25 times the rated load and hold for no less than 10 minutes, then inspect structural components for permanent deformation after unloading; 4) Dynamic load test—operate all mechanisms in combination under 1.1 times the rated load for no less than 1 hour. Only after all tests pass may the acceptance procedure be completed and the crane be put into operation.
