Pumps explosions

The convenience of the offered monitoring system consists in an opportunity fast adjustment in conditions of many nomenclature manufacture, reception of the protocol of the testing results, opportunity of use of the unskilled personnel. By an offered principle installations for the testing of welding by explosion of cases of plunger pumps, details of air engineering and other were developed. 

Chen S, Tolbert W A and DIott D D 1994 Direot measurement of ultrafast multiphonon up pumping in high explosives J. Phys. Chem. 98 7759-66... 

Control Room. The control room location can be critical to the efficient operation of a faciHty. One prime concern is to locate it the maximum distance from the most ha2ardous units. These units are usually the units where LPG or other flammables, eg, hydrocarbons that are heavier than air, can be released and accumulate at grade level. Deadly explosions can occur if a pump seal on a light-ends system fails and the heavier-than-air hydrocarbons coUect and are ignited by a flammable source. Also, the sulfur recovery unit area should be kept at a healthy distance away as an upset can cause deadly fumes to accumulate. 

Explosives. Sodium teUurite is used as a jelling promoter in explosive compositions that can be readily poured or pumped into drillholes (91)... 

Piping and pumps used for transfer of the butanols can be made of the same metal as tanks. Centrifugal pumps with explosion-proof electric motor drives are recommended (34). 

Cavitation Formation of transient voids or vacuum bubbles in a liquid stream passing over a surface is called cavitation. This is often encountered arouna propellers, rudders, and struts and in pumps. When these bubbles collapse on a metal surface, there is a severe impact or explosive effec t that can cause considerable mechanical damage, and corrosion can be greatly accelerated because of the destruction of protective films. Redesign or a more resistant metal is generally required to avoid this problem. 

When vapor bubbles eollapse inside the pump the liquid strikes the metal parts at the speed of sound. This is the elicking and popping noise we hear from outside the pump when we say that eavitation sounds like pumping marbles and roeks. Sound travels at 4,800 ft per second in water. The velocity head formula gives a elose approximation of the energy contained in an imploding cavitation bubble. Remember that implosion is an explosion in the opposite direction. 

The seal must also resist the vibrations from the explosions of internal combustion in the engine, chassis and wheel vibrations, and even potholes in the road. This seal must resist strong chemicals (anti freeze, anti-rust agents, radiator stop-leak and sealant chemicals, gasoline and lubricant residuals), and also solid particles (rust, iron slag, minerals, asbestos fibers, and silica from the engine casting mold). In spite of all this, the mechanical seal on the water pump of your car can run 7, 10, even 15 years without problems. 

This type of double seal (with back to back faces) is pressurized above the pressure inside the seal chamber (Figure 13-20). It is recommended for toxic, explosive, costly, dangerous, and volatile liquids. It is important to maintain the seal pressure above the pumped pressure inside the seal chamber. 

Information about the current generated and the resistivity of the particular hydrocarbon pumped is essential in order to calculate the voltage difference. This subsequently shows us whether the danger exists of selfignition or explosion in any particular case. 

In addition to the fluoroplastics and fluororubbers already described other fluoropolymers have been marketed. Polymers of hexafluoropropylene oxide are marketed by Du Pont (Krytox). These materials have a low molecular weight (2000-7000) and are either oils or greases. The oils are uses as lubricants, heat transfer fluids and non-flammable oils for diffusion pumps. The greases are also used as lubricants. They have good heat and oil resistance but it is said that explosions may result from contact with the surfaces aluminium or magnesium cuttings. 

Following some mtxiifications to a pump, an operator pressed the stop button on the control panel and saw that the pump running light went out hence closed a remotely operated valve in the pump delivery line. Several houi s later the high-temperature alarm on the pump sounded soon afterward there was an explosion in the pump... 

In 1984, an explosion in a water pumping station at Abbeystead, UK, killed 16 people, most of them local residents who were visiting the plant. Water was pumped from one river to another through a tunnel. When pumping was stopped, some water was allowed to drain out of the tunnel and leave a void. Methane from the rocks below accumulated in the void and, when pumping was restarted, was pushed through vent valves into a valvehouse, where it exploded [18J. 

The explosion was due to a failure to directly measure the property that we wish to know. The temperature point was not measuring the temperature in the reactor but the temperature near the pump. This got hot because the pump was running with a closed suction valve. Similarly, the trip initiator on J2 showed that its motor was energized. It did not prove that there was a flow. 

Several hours later, the high-temperature alarm on the pump sounded. Because the operator had stopped the pump and seen the Pump Running light go out, he assumed the alami was faulty and ignored it. Soon afterward an explosion occurred in the pump. 

When the pump was modified, an eiTor was introduced into the circuit. As a result, pressing the Stop button did not stop the pump but merely switched off the Pump Running light. The pump continued running against a closed delivery valve, overheated, and the material in it decomposed explosively. 

A more serious incident occurred at a plant in which ethylene oxide and aqueous ammonia were reacted to produce ethanolamine. Some ammonia got back into the ethylene oxide storage tank, past several check valves in series and a positive pump. It got past the pump through the relief valve, which discharged into the pump suction line. The ammonia reacted with 30 m of ethylene oxide in the storage tank. There w as a violent rupture of the tank, followed by an explosion of the vapor cloud, which caused damage and destruction over a wide area [4],... 

In 1966, a naphtha tanker, the Alva Cape, was involved in a collision near New York and was severely damaged. Some naphtha was spilled, and the rest was pumped out into another vessel. The owners wanted to move the ship to a shipyard where it could be gas-freed and the damage could be surveyed, but the New York Fire Department said that the ship s tanks should be inerted before it was moved. The salvage company, therefore, ordered some carbon dioxide cylinders and hoses. Two tanks were inerted without incident, but when carbon dioxide was discharged into a third tank, an explosion occurred, followed by a fire. Four men were killed, and further explosions occurred in other tanks when they were heated by the fire. 

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