PNNL Hoisting and Rigging Manual
| Scope | New Hooks | Throat Latches | Inspection | Nondestructive Testing |
Hooks
Scope
This section applies to hooks installed on cranes or hoists and implements the requirements of ASME B30.10. For rigging hooks, see Rigging Hardware.
New Hooks
When new hooks are purchased, pertinent requirements of ASME B30.10 shall be specified in the procurement document.
Performance Tests
Performance testing of hooks shall not be required except where necessary to conform to the requirements for the equipment of which they are a part.
When tests are specified, documentation shall be uniquely identified to the hook, by serial number, or other identifier.
Throat Latches
A latch, or mousing, bridges the throat opening of the hook for the purpose of retaining slings, chains, or similar parts under slack conditions and is not intended to support the load. Mousing shall not be used to secure the hook throat in manlift operations.
Latch-equipped hooks shall be used for all hoisting and rigging operations unless the application makes use of the latch impractical, or unsafe. The absence of a hook throat latch is not indiscriminately allowed. Unless a specific impractical or unsafe situation can be substantiated, the hook latch is mandatory.
Questions concerning requirements for throat latches shall be resolved by the Hoisting and Rigging subject matter expert.
Inspection
Inspection Classification
- Initial Inspection. Before initial use, all new and repaired hooks shall be inspected to ensure compliance with the applicable provisions of ASME B30.10, Hooks.
- Daily Inspection. Hook visual inspection shall be conducted daily (before use) by the operator or other designated person to identify the following:
- cracks, nicks, gouges
- deformation
- damage from chemicals
- damage or malfunction of the throat latch, if provided.
- Classifications. There shall be two general inspection classifications based on intervals at which examination shall be performed. The classifications are designated frequent and periodic, with intervals between examinations as defined below.
Frequent Inspection Interval
Visual examinations by the operator or other designated person with records not required:
- Normal service - monthly.
- Heavy service - weekly to monthly.
- Severe service - daily to weekly.
Hook Service Classifications
Normal service: Service that involves operating at less than 85% of rated load except for isolated instances.
Heavy service: Service that involves operating at 85% to 100% of rated load as a regular specified procedure.
Severe service: Heavy service coupled with abnormal operating condition.
Periodic Inspection Interval
Visual inspections shall be performed by a qualified inspector who shall record apparent external conditions to provide the basis for continuing evaluation:
- Normal service - yearly, with equipment in place.
- Heavy service - semiannually, with equipment in place unless external conditions indicate that disassembly should be done to permit detailed inspection.
- Severe service - quarterly, as in heavy service, except that detailed inspection may show the need for nondestructive type testing.
Frequent Inspection
- Frequent inspection shall include observations during operation.
- A designated person shall determine whether conditions found during the inspection constitute a hazard and whether a more detailed inspection is required.
- Hooks shall be inspected for the following items and conditions:
- distortion, such as bending, twisting, or increased throat opening
- wear
- cracks, nicks, or gouges
- latch engagement, damaged or malfunctioning latch (if provided)
- hook attachment and securing means.
Monthly and Periodic Inspections (Records Required)
- Monthly and periodic inspections shall include the requirements of Frequent Inspection, shall be done by a qualified person, and shall be documented.
- A monthly documented hook inspection is required on overhead and gantry cranes. Monthly hook inspection is a visual inspection for deformation, throat opening, and wear. Measurements are only required if the inspector finds evidence of distortion or damage. Monthly hook inspections on such cranes should be done in conjunction with the monthly wire rope or chain inspection. On manually operated lever hoists, overhead (underhung) hoists, jibs, and monorail systems, periodic hook inspection is required, but monthly hook inspection is not required.
- When monthly and periodic inspection fall in the same month, only the periodic documented hook inspection is required that month.
- Hooks having any of the following conditions shall be discarded:
- Deformation. Any bending or twisting visible to the inspector.
- Throat Opening. Any distortion causing an increase in throat opening exceeding 5% or as otherwise directed by the hook manufacturer.
- Wear. Any wear exceeding 10% of the original section dimension of the hook or its load pin or as otherwise directed by the hook manufacturer.
- Cracks. Any visible crack.
Inspection Records
For documented inspections, inspection records shall include the date of inspection, the signature of the person who performed the inspection, and the serial number, or other identifier, of the hook inspected. The most recent inspection records shall be retained in the equipment maintenance file. The following is a summary of inspection record requirements:
- Initial Inspection. A record of the initial inspection shall be made.
- Pre-use and Frequent Inspection. No records are required.
- Monthly and Periodic Inspection. A record of monthly and/or periodic inspections shall be made.
Nondestructive Testing
New Hooks
New crane/hoist hooks that will be assigned to critical lift service should receive an nondestructive test by the hook manufacturer. New crane/hoist hooks that will be assigned to heavy or severe service should receive an nondestructive test by the hook manufacturer. The nondestructive test method, acceptance criteria, and documentation requirements should be determined before the hook is purchased and specified on the purchase requisition.
CAUTION: Hooks purchased without an acceptable nondestructive test may not pass applicable in-service nondestructive test requirements.
Existing Hooks
Existing crane/hoist hooks with a rated load greater than or equal to 10 tons and assigned to heavy or severe service shall receive an NDT by a qualified inspector at the following intervals:
- Heavy service - annually.
- Severe service - semi-annually (every 6 months).
Note: Hooks in normal service do not routinely require nondestructive test .
Hook Service Classifications
Normal service. Service that involves operating at less than 85% of rated load except for isolated instances.
Heavy service. Service that involves operating at 85% to 100% of rated load as a regular specified procedure.
Severe service. Heavy service coupled with abnormal operating conditions.
Hooks in Normal Service
Hooks in normal service shall receive NDT for site-specific reasons if deemed appropriate by facility management, the equipment custodian, a qualified inspector, or another designated person.
Hooks with Potential Defects
If visual examination reveals a surface intersecting discontinuity, twist, increased throat opening, or any other potential defect, nondestructive test shall be employed to further evaluate the hook, regardless of the hook's service classification or rated load.
Hook Nondestructive Test Records
Dated and signed nondestructive test records, traceable to the hook by serial number or other identifier, shall be kept on file as long as the hook remains in service or is accessible for service. Nondestructive test records shall be readily available to appointed personnel.
Hook Nondestructive Test Methods
Magnetic particle testing or liquid penetrant testing methods shall be utilized to inspect for surface intersecting discontinuities (i.e., stress or fatigue cracks).
- Nondestructive testing shall be done in accordance with the following ASTM standards:
- ASTM E-709, Standard Practice for Magnetic Particle Examination
- ASTM E-165, Standard Practice for Liquid Penetrant Inspection Method
- For magnetic particle testing, a coil, yoke, or wet technique should be used to eliminate the possibility of prod burns or arc strikes.
- Nondestructive testing should be done with the hook in place unless conditions indicate that disassembly for thread or shank inspection is necessary.
Nondestructive Testing Acceptance Criteria
The following relevant indications shall be documented and resolved by a designated person:
- arc strikes (welding/electrical)
- surface intersecting discontinuities 0.25 inch long or longer.