Overhead And Gantry Inspections : Learn The Basics

To ensure both the safety and the optimal functionality of an overhead or gantry crane, it is critical to inspect a variety of components and operating functions at specific intervals. As recommended by the Crane Manufacturers Association of America (CMAA) specification CMAA 78 – Standards and Guidelines for Professional Services Performed on Overhead Traveling Cranes and Associated Hoisting Equipment, there are four primary types of crane inspections: Initial, Pre-Shift, Frequent, and Periodic. Additionally, inspections should align with the safety recommendations in ASME B30.2 Standard for Overhead and Gantry Cranes (Top Running Bridge, Single or Multiple Girder, Top Running Trolley Hoist).

Here, an overview of what each type of inspection should include, how frequently they should occur, and what components should be examined during each assessment.

Initial Inspection: This occurs after a new crane has been installed or an existing crane has been modified or repaired. An initial inspection verifies that the crane is in working order prior to commissioning to ensure that all safety and operational functions perform as intended. These inspections are performed by the original equipment manufacturer (OEM), and look at items such as clearances, operating speeds, lubrication levels, control settings, safety devices, and more. Documentation of the inspection is provided to the crane’s owner to keep on file for the life of the equipment. Additionally, if the crane was repaired, modified or altered, an initial inspection report documenting the affected areas should also be kept on file.

Pre-Shift Inspection: Sometimes called a daily inspection or a pre-operational check, these visual and operational assessments are conducted at the start of each shift by the crane user. These inspections include a variety of items, including confirming that the crane or hoist has not been tagged with an out-of-order sign; that all motions align with control device markings; that the hook and latch are not damaged or deformed and work properly; that the wire rope is not broken, kinked, or improperly wound; that the load chain is not worn, stretched, twisted or distorted; that travel limits and hoist limit switches function properly; and that there are no unusual sounds detected. These inspections may or may not be documented on paper or electronically, although more operations are requiring their crane operators to document that the assessment has been performed.

Frequent Inspection: The scheduling of frequent inspections depends on multiple factors, including how often the crane is used across how many shifts, the operating conditions, and the types of loads handled and their average weight (duty cycles). ASME B30.2 defines this as three different service classes: normal (with inspections required semi-annually to semi-monthly), heavy (with inspections required monthly to weekly), and severe (with inspections required weekly to daily). These inspections can be performed by a trained in-house employee or by an outside expert (either the OEM or a third-party inspection firm). All the same elements are examined as in a pre-shift inspection, but in more detail. All items should be recorded as inspected with the report kept on file for three years. Specifically, the inspection of the hook, wire rope, and load chain must be documented with a certification record that includes the date, signature of the inspector, and serial number (or identifier) of each component. Any safety hazards should immediately be reported to the crane owner.

Periodic Inspection: Highly detailed and exceedingly thorough, these inspections occur annually, semi-annually, or quarterly depending on the crane’s frequency of use, handled load characteristics, and operating environment. These evaluations are typically performed by an OEM or third-party inspection firm. They include all the items assessed in pre-shift and frequent inspections, as well as a comprehensive examination of structural and mechanical components. Reviewed are all girders, end trucks, foot walks, handrails, trolley frames, and cabs. Further, inspection for wear, cracks, or other damage is performed on brakes, shafts, axles, wheels, couplings, sheaves and drums, transmission components, runway structures, and below-the-hook devices. The inspector examines electrical components, indicators, gages, connection points, the trolley and runway rail, bumpers and end stops, covers and guards, and all self-contained electric, hydraulic or gasoline powered generating units. Reports are kept on file both by the crane owner and the company that performed the inspection. These reports document all findings and identify safety hazards, maintenance issues, and code or standard violations, as well as make recommendations for corrective actions. If a repair is warranted, the owner may elect to request a second opinion (particularly if the repair is costly) and may choose whom they wish to perform the work.

In addition to identifying areas in need of service, the previous documentation collected from each of these four types of assessments is typically referred to by the inspector as a means to both pinpoint areas for additional review and determine trends in wear or usage. This information can be used to better develop a strategic maintenance and service plan to help prolong the life of the equipment and improve total cost of ownership.

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