Exchanger tube leaks

GHXTLK Glycol heat exchanger tube leak... 

Greater Fluid Density - Exchanger Tube Leaks... 

Effects of heat exchanger tube leaks into the column include off-spec products and/or undesirable chemical reactions. In some cases, this reaction may lead to rapid corrosion or plugging. It is important to realize that material leaking at the condenser or at an intermediate exchanger may travel to the column base and decompose there. In one vacuum column, water leaking at the condenser reached the reboiler and caused a pressure surge and tray damage (358). 

Effects of heat exchanger tube leaks out of the column include inability to maintain column pressiure, erratic performance of reboiler or condenser, and erratic performance in other units because of contamination of the heat transfer medium. One classic experience (239) of an extremely sick column performance caused by a leaking reboiler was described in Sec. 1.2. 

Steam Generator Tube Rupture SCS Heat Exchanger Tube Leak Total Loss of FW Flow... 

In selecting modification options, practical constraints were considered. For example, the reaction effluent stream was not used for MP steam generation. This constraint was to protect the steam system because in case of exchanger tube leaks, reaction effluent could leak into the steam system. 

Heat exchanger tube leak moisture ingress, reactivity insertion... 

Heat exchanger valve Mures or heat exchanger tube leaks (20 gpm)... 

About 15 years before the explosion, corrosion of the condenser tubes had caused a series of exchanger tube leaks. The cause of failure was thought by Shell to be due to acidic components (HCN, CO2, HjS) in the vapor phase. To combat the tube failures, two changes were made ... 

Equipment Failure pumps, tubes in heat exchangers and furnaces, turbine drivers and governor, compressor cylinder valves are examples of equipment which might fail and cause overpressure in the process. If an exchanger tube splits or develops a leak, high pressure fluid will enter the low side, overpressuring either the shell or the channels and associated system as the case may be. 

Failure of Heat Exchanger Tubes If a heat exchanger shell rating is less than the pressure level of the circulating medium and an internal heat exchanging tube ruptures or leaks it will overpressure the vessel. 

Heat exchangers that can be blocked in or where the shell of the exchanger may be subject to high pressure if an internal tube leak occurs. 

TEMPERATURE HIGH Ambient Conditions Fouled or Failed Exchanger Tubes Fire Situation Cooling Water Failure Defective Control Valve Heater Control Failure Internal Fires Reaction Control Failures Heating Medium Leak into Process Faulty Instrumentation and Control... 

Tube leaks may occur in the reboiler, condenser, preheater, precooler, or any other heat exchanger linked with the column. Several experiences where leakage caused poor performance have been reported (71, 238, 239). The effect of a leaking heat exchanger tube depends on the magnitude, the direction, and the location of the leak. 

Using the preliminary test run, perform material balances on the unit and each column Ensure that these close within 5 percent. Do not proceed with the performance test if the closure is worse than 10 percent (118). Leaking valves and exchanger tubes will affect the material balance, and these leaks need to be identified prior to the final test. Meters have happened to read incorrectly even at times when the instrument people were sure they were... 

The commissioning and operation of sodium systems and components have been smooth and performance of major components, viz., sodium pumps, intermediate heat exchangers and once through sodium heated steam generators (SG) have been excellent. There have been three minor incidents of Na/NaK leaks during the past 14 years, which are described in the paper. There have been no incident of a tube leak in SG. However, three incidents of water leaks from water / steam headers have been detailed. 

The other aspect of noble metal plate out is the fact that heat exchangers will be substantially activated, which greatly complicates service and/or repair. The design philosophy of early developers was to strive for the highest quality of construction, and if tube leaks or other defects did arise, to shutdown and swap out the entire tube bundle. Only after years in shielded storage would a decision be made on tube bundle repair. 

Design thermal capacity - the maximum thermal power that may be transferred from the primary to secondary circuit by one steam generator. It is approximately equal to the rated reactor thermal power divided by the number of steam generators. The actual SG capacity may be lower due to plugged heat exchanging tubes that had been leaking. The original (as manufactured) value should be entered in MW. 

Design heat transfer snrface - the total surface of all the heat exchanging tubes in one steam generator. It is the product of the total number of tubes in a new SG and the lateral area of a tube (cylinder). The actual value may decrease during plant service as a result of successive plugging of leaking tubes. The original (as manufactured) value should be entered in m. ... 

The condensate polishing system chemically cleans up the condensate by passing it through ion exchange resins to remove corrosion products and ionic impurities. It is required during start-up, imtil the desired water quality is attained, but during power operation would be used only when abnormal secondary conditions exist, such as a continuous condenser tube leak. 

The potential design improvement proposed system is intended to enhance its capability so that it could intervene following a small or intermediate loss of coolant accident (LOCA), such as would result from a reactor coolant system leak or a tube leak within the passive residual heat removal heat exchanger, to keep the core covered during such LOCAs. This increase in capability would be achieved by means of the following severe accident mitigation design alternatives (SAMOA) enhancements ... 

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