Fire pump steam

Water pressure is a key consideration in terms of the adequacy of application and system operation and maintenance. While some domestic supplies have high pressure systems, most are in need of pressurization, as is water from bodies of water and tanks. Fire pumps are routinely used, most often in multiple installations with different means of power drive (e.g., electric, diesel, or steam). When fire pumps operate at high pressures, there is the potential for leaks and line fracture. Periodic maintenance, including hydrostatic testing, will help minimize the potential for such failures. 

The three drivers recognized by the NFPA code on fire pumps are diesel, electric and steam. The diesel fire pump is the preference of most insurance companies. They have a long history of satisfactory service. These units tend to be more expensive especially when they are used with vertical turbine pumps. With vertical turbine pumps, they require a right-angled drive which significantly increases the cost. They are self-contained and do not depend on outside utilities. 

Main fire pumps should be automatically controlled to start whenever there is a demand that reduces system pressure below a set point of say 7 barg. They should be large enough to keep the pressure above that set point at the most distant hydrant and at the system design flow rate. Spare pumps should be diesel engine driven with independent fuel tanks. Where steam is available, steam-driven pumps may be used to supplement the electric- and diesel-driven units. 

Hot process lines need to be able to handle thermal expansion even with lines expected to operate at normal temperatures it is desirable to provide sufficient flexibility for expansion and contraction caused by changes in atmospheric temperature, possible fire exposure, steam out, and pump out. Flexible couplings may fail rapidly under fire exposure and should be avoided wherever possible in systems handling hydrocarbons. The use of offsets in welded pipe is much safer. 

After the fire, the pump (and others) was relocated in the open air, under a canopy, so that small leaks would be dispersed by natural ventilation. It was surrounded by a steam curtain to disperse larger leaks. This would not have been necessary if the pump could have been located more than 150 m from sources of ignition. Gas detectors were installed to give early warning of any leaks. Emergency isolation valves (Section 7.2.1) were provided so that the pumps could be isolated safely from a distance [9]. What happened when another leak occurred is described in Section 7.2.1 (d). 

In subsequent years, Savery made important improvements that benefited future steam inventions. In June 1699 he demonstrated to the Royal Society a pump with two receivers, each with a separate, hand-controlled steam supply. This ensured improved continuity of operation, allowing one receiver tn operate in its vacuum stage and the other under steam pressure. In 1701, he added two more critical steps a second boiler, avoiding the need to shut down the fire and pump, between stages and he replaced the two interconnected steam cocks with a single valve, run with a manually operated long lever. This may have been the inspiration for the modern slide valve and his inventiveness created, in effect, the world s first feed-water heater. 

Savci"y appeared to he the first to take the huge step out of the lab and into the practical workshop. His equipment was made of brass and beaten copper, using firebrick furnaces. It was said that Salisbui y Court (extending from Fleet Street to the river Thames) was the site of the world s first steam pump factoi y, although there is evidence that Savery abandoned his project in 1705. The limitations of his progress became known, literally under fire. 

Power will be purchased from a nearby company. (One of the major reasons for locating here was the presence of low-cost, plentiful power.) A gas-fired plant for 125 psig steam will be built. This must be able to supply enough power to operate agitators and cooling-water pumps associated with the reactors when there is a power failure. Gas will be purchased from a local company. Drinking water will be purchased from the community of Martins Ferry, Ohio. Process and cooling water will be obtained from the Ohio River. Both will require treatment before they can be used in the plant. 

The Cheshire brines, which are of specific gravity l SOO, and contain about 24 per cent, cf common sail, are of so pure a quality that they require no preliminary fobruation. The brine is, therefore, at once run into the evaporating pans, which are of sizes varying with the source of heat, and evaporated by the direct action of the fire, or by the waste heat of the steam engine used to pump up the brine. 

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