The Story of the Fire Pump
-Hale Fire Pump Company photo.
Part 3: Centrifugal pump era and advent of high pressure
Centrifugal-type fire pumps were not well adapted to use on either hand or steam fire engines. It was not until the invention of the modern form of high-lift centrifugal pump by Professor Osborne Reynolds in 1875 that a design basis for a centrifugal pump was established to provide satisfactory fire service. When the gasoline engine with its higher rotative speed was made available, the application of the centrifugal pump to the fire service was not long in developing.
In 1911 the Seagrave Corporation at Columbus, Ohio, built the first selfpropelled, gasoline-powered pumper with a centrifugal fire pump. The pump was a four-stage, diffusion-vane type. This was exhibited and tested in September 1911 at the 39th Annual Conference of the International Association of Fire Engineers (now the International Association of Fire Chiefs) in Milwaukee. The tests were supervised by engineers from the National Board of Fire Underwriters.
Following the Milwaukee Conference, certain standards of performance for the pumps were established to be effective at future conferences. The pump capacity rating was set at the next lower 50-gallon figure from the average pumped at 120 psi. This capacity test was established for 6 hours’ duration. It was to be followed immediately by a 3-hour test with the pump discharging one-half capacity at 200 psi and 3 more hours at a discharge of one-third the capacity at 250 psi. Tests were to be conducted with the pump operating at draft with a lift of approximately 10 feet.
These standards continued until 1919, when the National Board of Fire Underwriters decided to test at the factory instead of at the annual IAFC Conference.
Standards for pump capacity were also established. Standard pump capacities were 500, 600, 750 and 1000 gpm. A few years later the 1250-gpm rating was added.
Ahrens Fox uses motor
In 1912, the Ahrens Fox Fire Engine Company at Cincinnati built its first self-propelled, gasoline-powered piston fire pump. The design was characterized by the pump being mounted ahead of the gasoline engine, with a large nickel-plated air dome prominently at the very front of the apparatus.
The Waterous Company built the first gasoline-powered, self-propelled pumpers to go into service in several of the larger cities. One of the pumpers delivered to New York City was equipped with a rotary pump with a capacity of 900 gpm.
In 1913 American LaFrance built and delivered its first gasoline piston pumper.
In 1914, American LaFrance built the last steamer, which ended an era of steam power in the fire service covering 85 years. With the passing of the horse-drawn steamer went some of the glamour of the service that mechanized power never replaced.
In 1914 the Hale Fire Pump Company was organized at Conshohocken, Pa. The first fire engine built by Hale had a rotary pump on a Simplex chassis. Most fire pumps are tested by the manufacturer in a dull, routine procedure, but this new Hale pump got a real-life fire test. It had a sixhour continuous workout at the big Opera House fire at Wayne, Pa., in December 1914. As a result of this fine performance, the pumper was sold immediately to the George Clay Fire Company at West Conshohocken, Pa.
In 1914 American LaFrance built its first centrifugal fire pump, a fourstage, diffusion-vane type.
1914 also marked the beginning of the use of a commercial chassis for mounting a pump and fire fighting equipment. As noted, the Hale Fire Pump Company started by using the Simplex chassis. In 1914 the Waterous Company discontinued building its own chassis. From that time until 1929, when they discontinued building complete vehicles, Waterous concentrated on the design and manufacture of fire pumps.
Old equipment motorized
During the period of changeover from the horse-drawn steamer to the motorized pumper, many fire departments wished to quickly motorize the entire department and give up the horses. The steamers were in too good an operating condition to discard, and the cost of buying all motorized equipment at one time was prohibitive.
The solution was a two-wheel, front-drive, motorized tractor that could be attached to the front of horse-drawn apparatus. This was manufactured from about 1914 to 1936.
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In 1920, E. J. Wendell of the Hale Fire Pump Company developed the three-lobe (clover leaf) rotary pump. The first pump built had a rated capacity of 300 gpm.
In 1927, the Fire Engine Division of Mack Trucks, Inc., at Allentown, Pa., was the first to introduce the pressurevolume, or parallel-series, two-stage centrifugal fire pump. This type of centrifugal pump found favor with the fire service and continues to be the type most preferred.
In 1930, Seagrave replaced the four-stage diffusion-vane centrifugal pump with a parallel-series, two-stage volute-type centrifugal pump.
In 1930, American LaFrance discontinued the production of piston fire pumps.
Booster pumps developed
By 1930 the 30 and 40-gallon sodaacid chemical tanks were being superseded by water tanks, 100 gallons or larger, on new apparatus. This change brought into use a new class of small fire pumps called “booster” pumps.
The discharge rating of the booster pumps varied from 50 to 200 gpm at 120 psi. Since the booster pump was first introduced in 1930, the rated capacity has increased to a standard of 200 to 250 gpm. Generally, the maximum pressure for this class of pump is 200 to 250 psi. The booster pumps are either rotary or single-stage, volute centrifugal.
In 1931, the Hale Fire Pump Company announced the availability of a complete line of single-stage, volute centrifugal pumps to 750-gpm capacity and parallel-series, two-stage, volute centrifugal pumps to 1250-gpm capacity to supplement their line of rotary pumps.
In 1934, American LaFrance replaced the four-stage diffusion-vane centrifugal pump with a line of singlestage, volute, centrifugal pumps (rated capacity to 750 gpm), and parallel-series, two-stage, volute, centrifugal pumps with capacities of 1000 gpm and 1250 gpm.
In 1934, American LaFrance was the first to use the double-suction, single-stage, centrifugal fire pump to provide increased capacity. The pump was built in only one rated capacity, 1000 gpm.
In 1938, American LaFrance discontinued the use of the double-suction, single-stage, centrifugal pump in favor of the parallel-series, two-stage, centrifugal pump.
In 1938, the John Bean Division of the Food Machinery Corporation at Lansing, Mich., was the first to introduce a high-pressure booster pump. This high-pressure pump is a triplecylinder, single-acting piston type, with a rated capacity of 70 gpm at 850 psi.
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The Story of the Fire Pump
Continued from page 48
Other manufacturers, to provide a comparable performance, developed different designs. Hale and Waterous developed a power takeoff two-stage high-pressure centrifugal pump. American LaFrance, Byron Jackson, Seagrave and Van Pelt developed fourstage high-pressure centrifugal pumps.
The Waterous Company developed a third stage for the standard parallelseries centrifugal pump to provide the desired high pressure plus the ability to operate 1 1/2-inch lines simultaneously.
The Hale Fire Pump Company also produced a third stage for high pressures on the standard parallel-series, two-stage centrifugal pump.
In 1936 the Hale Fire Pump Company developed a trailer-mounted single-stage centrifugal pump with a gasoline engine. In 1938 the design was licensed to England and thousands were in service during the Blitz.
The design was also adopted by the Office of Civil Defense and many were used during World War II.
In 1943 the Hale Pump Company developed a portable fire pump that has become an essential in every fire department. Many changes and improvements have been made since its introduction. The general capacity rating, while varying with different manufacturers, is 160 gpm at 20 psi to 100 gpm at 90 psi.
Portable pumps are produced by several other manufacturers, including the Gorman-Rupp Company, American LaFrance, American Fire Pump Company, Pacific Pumpers and Bilgram Gear and Machine Works.
In 1949 the National Board of Fire Underwriters changed pump ratings to reflect a higher capacity test pressure and an increase in volumes at 200 and 250 psi. This change was requested by the fire pump manufacturers because improved pump efficiency and higher horse-power engines made it possible. The standard rating of capacity at 120 psi, one-half capacity at 200 psi and one-third capacity at 250 psi became a Class B rating. The new rating, Class A, requires capacity at 150 psi, 70 percent of capacity at 200 psi and 50 percent of capacity at 250 psi.
In 1953 the John Bean Division announced a parallel-series, two-stage centrifugal pump to permit meeting larger discharge capacities than could be obtained from the high-pressure pump. The addition of the larger pump with a Class A rating permitted insurance credit for the pumper equipped with the high-pressure pump.
While other manufacturers discontinued the manufacture of piston pumps (except for high pressure), the Howe Fire Apparatus Company continues to build a piston pump, usually for mounting on a commercial chassis. The pump has a rated capacity of 500 gpm.
Front-mount, single-stage centrifugal fire pumps, first introduced by The American Fire Pump Company in 1924, came into use particularly in rural areas where access to a water source was best with the pump mounted up front. Such pumps are produced and mounted by American Fire Pump and W. S. Darley. They are made by both Hale and Waterous for installation by apparatus builders.
Different pump design
A rather unusual design of centrifugal pump, the Duplex, is produced by the American Fire Pump Company at Battle Creek, Mich. Rated capacity is obtained by operating only the large impeller. The 70 percent of capacity rating at 200 psi is obtained by operating singly the smaller impeller. The one-half capacity rating at 250 psi is obtained by operating the impellers in series. A small two-stage unit is available for mounting on the side of the pump housing with suitable drive to provide four-stage high-pressure operation.
The Waterous Company has built the largest capacity centrifugal fire pumps to be mounted on a regular fire pumper chassis. The rated capacity is 2000 gpm at 150 psi. Several are in service at Los Angeles and Minneapolis, where the first went into service in 1947.
The largest fire pumps to be mounted on mobile equipment for fire service were delivered to New York City by Mack in 1965. The pump is a parallel-series, six-stage centrifugal pump with a capacity rating of 8800 gpm at 350 psi in parallel arrangement. It will discharge 4400 gpm at 700 psi in series. The engine, an 18-cylinder diesel of 2400 hp at 1800 rpm, and the pump are mounted on a trailer as a unit. The pump was built by DeLaval Turbine, Inc., and the engine is a Napier Deltic.