Pump Leak Incidents

Pumps can overheat if they run with the delivery valve almost closed. In one incident a pump designed to deliver 10 tons/hr was required to deliver only 14 ton/hr. The delivery valve was gagged, the pump got too hot, the casing joint sprang, and the contents leaked out and caught fire. 

In another incident, a maintenance foreman was asked to look at a faulty cooling water pump. He decided that, to prevent damage to the machine, it was essential to reduce its speed immediately. He did so, but did not tell any of the operating team immediately. The cooling water rate fell, the process was upset and a leak developed in a cooler. 

The process involved in the incident is concerned with the separation of crude into three phases. The crude is pumped into a two stage separation process where it is divided into three phases oil, gas, and water. The water is cleaned up and dumped to drain. The remaining mixture of oil and gas is then pumped into the main oil line where it is metered and sent on for further processing. A simplified process diagram is shown in Figure 7.1. The case study described here is centered on a flange leak in one of the oil pipeline pumps (pump A) and its associated pressure relief valve piping. 

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 performance of sodium pumps has been very good. The only incident of concern has been oil leaks with a major incident occurring in PFR [4]. Other problems like excessive vibrations, seizure, malfunctioning of speed control etc have been understood. 

The primary area of protection should be centered on the fixed equipment at the produa transfer area, the highest probable leak, or the spillage location. These include loading arms, hoses, pipe connections, and transfer pumps. Protection of fixed equipment ensures rapid restart after the incident with... 

The reaction cell is evacuated by a 300 L/s turbo molecular pump and equipped with a sample manipulator with a cryostat, variable leak valves for gas introduction, and a vacuum gauge. The incident X-ray beam is introduced through a 100 nm thick silicon nitride film which separates the beam line and the reaction cell. The sample is irradiated by the X-ray beam with a grazing incidence angle of 15° and emitted photoelectrons travel approximately 1 mm to the entrance of an aperture under near ambient pressure gas and enter the first stage of the differential pumping system via a hole of 1 mm in diameter as illustrated in Fig. 9.9. The electrons further travel... 

While health hazards to personnel are the primary concern, damage to the facility is another serious problem. And while spills or leaks from failing pumps are costly enough because of the loss of material and the time needed to clean up, there is also the possibility of EPA or OSHA fines should these incidents need to be reported. 

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