Document: NUREG-0800
Document ID: 90f64116-09ca-459d-8277-ecf8fc888100
Document Type: srp
Title: EMERGENCY DIESEL ENGINE LUBRICATION SYSTEM
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0520/ML052070572.pdf
Revision Date: 2023-06
Chapter: 9
Section ID: 9.5.7
CFR Part: 
CFR Title: 

Content:
fe . The operating pressure, temperature differentials, flow rate, and heat removal rate 38 of the system external to the engine are in accordance with recommendations of the engine manufacturer. gf . The system has been provided with sufficient protective measures to maintain the 39 required quality of the oil during engine operation. hg . Protective measures (such as relief ports) have been taken to prevent unacceptable 40 crankcase explosions and to mitigate the consequences of such an event. ih . The temperature of the lubricating oil is automatically maintained above a 41 minimum value by means of an independent recirculation loop including its own pump and heater, to enhance the "first-try" starting reliability of the engine in the standby condition. ji . The diesel engine is provided with a dedicated lube oil system design which 42 includes measures to provide lubrication to the diesel engine wearing parts during standby conditions and/or normal and emergency starts. Plants that have emergency ac sources in excess of minimum redundancy requirements for loss-of-offsite-power conditions may use one of the existing emergency sources as an alternate ac (AAC) power source for the purposes of coping with a station blackout, provided it meets the applicable criteria for an AAC source. For a plant relying on an emergency diesel engine as an AAC power source, the design of the lubrication system for that engine is acceptable if it meets 10 CFR Part 50.63, "Loss of All Alternating Current Power," paragraph (a)(2), and Regulatory Guide 1.155, Position C.3.43 Technical Rationale:44 The technical rationale for application of the above acceptance criteria to the emergency diesel engine lubrication system is discussed in the following paragraphs. 1. GDC 2 requires that SSC important to safety be designed to withstand the effects of natural phenomena such as earthquakes, tornadoes, hurricanes, floods, tsunami, and seiches without loss of capability to perform the safety