Emergency Diesel Generator Testing

Only available on StudyMode
  • Download(s) : 1355
  • Published : October 16, 2008
Open Document
Text Preview
EMERGENCY DIESEL GENERATOR HEAT EXCHANGER TESTING
C. M. D’Angelo
M. E. Kerst
Proto-Power Corporation
591 Poquonnock Road
Groton, CT 06340

and

S. M. Ingalls
Northeast Nuclear Energy Company
Rope Ferry Road
Waterford, CT 06385

EMERGENCY DIESEL GENERATOR HEAT EXCHANGER TESTING
C. M. D’Angelo
M. E. Kerst
Proto-Power Corporation
591 Poquonnock Road
Groton, CT 06340

and

S. M. Ingalls
Northeast Nuclear Energy Company
Rope Ferry Road
Waterford, CT 06385
Abstract
Nuclear Regulatory Commission (NRC) Generic Letter 89-13 requires periodic testing of all raw-water-cooled safety-related heat exchangers to ensure that the General Design Criteria of 10 CFR Part 50 are being met. Specifically, GL 89-13 addresses the requirements of GDC 44--Cooling Water, GDC 45--Inspection of Cooling Water System, and GDC 46--Testing of Cooling Water System. The heat exchangers associated with the Emergency Diesel Generators (EDG) at most nuclear power plants are raw-water cooled and safety-related, and therefore, fall under the requirements of GL 89-13. Whereas most of the larger safety-related heat exchangers can be tested and the resulting data reduced to an easily understood baseline value such as fouling factor, the EDG heat exchangers usually can not be tested in this manner due to lack of instrumentation, complex piping configurations, and automatic temperature-sensing flow control valves. The operational questions posed by GL 89-13 could be resolved readily if the EDG heat exchangers could be tested exactly at the conditions required or postulated by the most limiting accident scenario. Some of these parameters, such as kilowatt loading, can be easily attained; however, certain parameters such as the cooling water inlet temperature, or the external ambient air temperature may not be controllable. Such is the case with the Emergency Diesel Generator heat exchangers at Millstone Point Unit 1 (MP1). This paper details a test procedure that determined the operability of the MP1 EDG heat exchangers using test results with inference rather than absolute means. The procedure was used to determine the operability of the EDG heat exchangers during August 1995, and will again be used during August of 1996. Although the procedure detailed here is specific to that used at MP1 and which will be used at Millstone Point Unit 2 (MP2), the concepts can be applied to heat exchangers that pose similar testing restrictions. Background

The Millstone Point Unit 1 Emergency Diesel Generator is equipped with a heat exchanger assembly consisting of an Intercooler Water (IW) Cooler, Lube Oil (LO) Cooler and Jacket Water (JW) Cooler, that provides cooling for the respective EDG operating fluids. These three heat exchangers are installed in series and are cooled by the plant Service Water System (SWS). This paper details the theory and methods applied to evaluate the Emergency Diesel Generator (EDG) test data gathered during the August 1995 test. The August 1995 test served as the initial evaluation to verify that the EDG heat exchangers have sufficient heat transfer capacity to perform their safety related functions at design basis accident conditions, and to provide baseline data for future test comparison.

In accordance with the Reference (1) requirements regarding performance testing and evaluation of safety-related, open-water-system cooled heat exchangers, Northeast Nuclear Energy Company (NNECO) used special instrumentation to gather test data on the EDG heat exchangers operating under controlled conditions which simulated, as close as was practical, the design basis accident conditions for the EDG heat exchangers. The design accident conditions and the test conditions are shown in Table 1.

Table 1: DESIGN ACCIDENT vs. TEST CONDITIONS
ParameterDesign Accident ConditionDesign Accident Ref.Test Value SWS Flow (GPM)340Reference (2)369.568
Kilowatt Load26652665
SWS Temp. (F)75 (77)Reference (3)72.16...
tracking img