Document: NUREG-0800
Document ID: 28a7b60c-ac66-4869-9189-83f494a5059d
Document Type: srp
Title: NUREG-0800
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0523/ML052350042.pdf
Revision Date: 2023-06
Chapter: 9
Section ID: 9
CFR Part: 
CFR Title: 

Content:
osed, or if entry is administratively controlled. e. The design contains an independent circulation loop to maintain the temperature of the crankcase oil above a minimum value during the standby mode. f. The system P&IDs indicate the temperature, pressure, and level sen- sors which alert the operator when these parameters exceed the ranges recommended by the engine manufacturer. g. The system has been designed to minimize the potential fire hazard from lube oil leaking and accumulating on the engine exhaust mani- fold and in the turbocharger housing as a result of excessively long prelubrication of the engine prior to starting. The prelube time interval prior to manual starting of the engine should be limited to 3 to 5 minutes unless otherwise recommended by the diesel engine manufacturer. h. The system has been designed to preclude dry starting of the diesel engine during emergency starts, that is, the momentary lack of lubri- cation at the various moving parts or bearing surfaces resulting from the tendency for the lube oil system to drain during long periods of standby. It is necessary for the system to establish as quickly as possible an oil film on the wearing parts of the diesel engine; otherwise, damage to the bearing surface will result causing unavail- ability-of the engine. To remedy this situation, any one of the following may be used and should be confirmed with the diesel engine manufacturer: (1) An electrically driven lubricating oil pump powered from a reli- able DC power supply, and installed to operate in parallel with the engine-driven main lube oil pump. The electric-driven prelube 9.5.7-5 Rev. 2 - July 1981 pump should operate only during the engine cranking cycle or until satisfactory lube oil pressure is established in the engine main lube oil distribution header. (2) Installation of a continuously operated prelube system which would provide lube oil to all moving parts and bearing surfaces during the standby condition of operation. Appropriate