Document: NRC Regulatory Guide
Document ID: 626cd346-6298-4966-a92d-c5d4b24bbc2b
Document Type: regulatory_guide
Title: Overhead Crane Handling Systems for Nuclear Power Plants
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1303/ML13038A096.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.104
CFR Part: 
CFR Title: 

Content:
ing some of the intended operating temperatures, so that testing of the material toughness becomes necessary. Specifically, the nil-ductility transition temperature (NDTT) should be determined. Safety Features General. Numerous applications have been reviewed by the staff, and the need for inclusion of certain safety features and the magnitudes of specific operational limits to provide adequate safety have been determined. It is. important to prevent the release of radio- activity in case of failure, inadvertent operation, mal- function, or loss of load, and it may be necessary to include special features and provisions to preclude system incidents that would result in release of radio- activity. A crane that has been immobilized because of mal- function or failure of controls or components while holding a critical load should be able to set the load down while repairs or adjustments are made. This can be accomplished by inclusion of features that will permit manual operation of the hoisting system and the bridge and trolley transfer mechanisms by means of ancillary, auxiliary, or emergency devices. A crane handling system includes all the structural, mechanical, and electrical components that are needed to lift and transfer a load from one location to another. Primary or principal load-bearing components, equip- ment, and subsystems such as the driving equipment, drum, rope reeving system, control systems, and braking means should receive special attention. All auxiliary hoisting systems of the main crane handling system that are employed to lift or assist in handling critical loads should be provided with the same safety features as the rest of the main crane handling system. Hoisting Machinery. Proper support of the rope drums is necessary to ensure that they would be retained and prevented from falling or disengaging from their 1.104-2 braking and control system in case of a shaft or bearing failure. Two mechanical holding brakes in the hoisting system (raising