AT THE HEART OF THE ROAD TRANSPORT INDUSTRY.

Call our Sales Team on 0208 912 2120

Leith's Certificate of Halley Fire-engines.

9th February 1911
Page 7
Page 7, 9th February 1911 — Leith's Certificate of Halley Fire-engines.
Close
Noticed an error?
If you've noticed an error in this article please click here to report it so we can fix it.

Which of the following most accurately describes the problem?

T. B. LA1No, Esq., Town Clerk, Leith.

Dear Sir,—In connection with the above, we have made several exhaustive tests to determine whether' the engines frilly comply with the conditions of the speeificatiou, and, dealing with these in the order of the tests, beg to report: 1) On the 3rd curt, a pumping test of both engines took place at the Public Baths in presence of members of the Town Council. The terms of the specification are " that the turbine pump would deliver 450 gallons per minute, at a pressure of 90 lb. per square inch." To fulfil this lest, the level of the water of the swimming bath was reduced, so that the quantity of water delivered by each engine, during tr spccitied time, could he easily ascertained, The dimensions of the swimming bath were also carefully measured, and it was found that each inch in the rise of the water was equivalent to 1396.17 gallons, or each feot to 16,754 gallons. The rise of water was mentioned in decimals.

Pump No. 4 was started in the forenoon, taking water from the collecting dam, and worked for an hour continuously at the specified pressure, when it, was found that the rise in the water was 1.98 feet. or equivalent to a delivered gallonage per hour of 33,172.92 gallons, or 552.9 gallons per minute ; as gainst 27,000 gallons per hour, or 450 gallons per tilimite, as per specification, an excess of 6,172.92 gallons per hour, or of 102,9 gallons per minute respectively over the speeification.

The pump was kept working after the measurements had been taken, at a similar pressure, for a further period of 14 hours; thus the pump had a continuous pumping test at 93 lb. pressure fur 24 hours.

The swimming bath was run off, and a similar test: tonk plauo with No. 3 pump in the afternoon, when it was found that. the rise in the water was 1.96 feet, or equivalent to a delivered gallonage per hour of 32,837.84 gallons. ur 547.3 gallons per minute, as against 27,000 gallons per hour, or 450 gallons per minute, as per specification. an excess of 5.837.84 gallorts per hour, or of 97.3 gallons per minute. over the

iecificat This pump was also kept working for 24 home continuously.

Thus the combined success beyond that of the specification tvas 12,010.76 gallons per hour, or an average of 6.005.38 gallons each, or a further average of 100 gallons per minute egch over the specification.

The consumption of petrol for each engine during the period of test was 14l, gallons, or 5.8 gallons per hour. (2) On Saturday the 5th inst. (Suction Test per S plc; flea

5 ft. lift,") in presence of the Town Council and several conveners and firemasters from other burghs, the following tests took place, viz.—A suction test at the Albert Uraving Dock, No. 4 engine, from the starting of the pumps, ofrtc Ming water, from a depth of 25 ft, from the plump, in al Hee., and throwing water at the jet in 40 sec. The pressure

the pump was 125 lb., with a vacuum of 13 lb. No 3 engine, at similar pressure and vacuum, obtained water in JO sec., and at the jet in 24 sec. The depth of the suction was previously accurately measured by us. Each pump was continued working for from 15 to 20 min., the effective distance ofthe water thrown, measuring from the point of the nozzle of the hose, being about 190 ft.

litter ist. —The specification provided that " with two 7, in. jets, the effective vertical stream will he about 100 ft. with the pressure at the pump about 120 lb.; and with a l in.

jet, the height, of the effective vertical stream will be about 90 ft., and the pressure at the pump will be about 120 lb." These tests, along with others, were similarly effected on the same day at the Links, and also a comparative test with that of the 600 gallon steam tire-engine, arid below is a tabulation of the results.

The heights to which the water reached were ascertained by Mr. Findlay, burgh surveyor, by means of the theodolite. The pumps were fed direct from Water Trust's 12 in, water main. Instead of obtaining accelerated pressure each pump indicated Irvin 2 to 4 lb. on the vacuum gauge.

(a) Off collecting dam throughout. The jets varied from 20 to 40 feet less in height in each test than those of the motor pumps.

(b) Pump working from collecting dams.

(3) " S' pest1.—To carry a load lof 3 tons at. a maximum speed of 30 miles per hour."

On the 7th curt., with No. 4 motor, speed and brake tests took place between Davidson's Mains and Queensferry, on the Queensferry Road, and also brake and hill-climbing tests at Hawe's Brae at Queensferry and at Corstorphine Hill, and the following is a tabulated statement of the result of the former :— • The variation in speed was due to the hilly natore of the read and slowing down when passing traffic. During the speed testa the governor was set to restrict the revolutions of the engine to 1,000 per minute, otherwise, had it not been so restricted, the speed would have been greater. With regard to the brake tests, the motor was drawn up twice in from one or two lengths of itself in going down Ilawe's Brae, and likewise going down the steep incline towards Corstorphine, on the Corstorphine Hill. and again two or three times on the incline from the head of the hill to Queensferry Road. The engine, in climbing, also took these hills readily on the second, or 1.8 miles per hour gear. The time occupied from opposite the Jetty at Queensferry

to the summit of Havve's Brae was 1 min. 13 sec. The length of Hawe's Brae is about 550 yards, and the incline is about 1 in 13. The length of Corstorphine Hill is 1 mile 660 yards, and of the steepest portion of the Brae going to and coming from Corstorphine, about 440 yards is 1 in 9.

All these tests clearly demonstrate that the petrol motor combined pump and fire-engines each exceed in every respect the specification.

With regard to the other conditions of the specification regarding seating, gearing, engines, governor, fuel, outfit, lamps, etc., these we 1-ave carefully examined, and we are satisfied that the petrol motor combined pump and fire. engines fully comply with the specification.

(Signed) GEORGE SIMPSON, Town Architect.

75 JOHN Y011c0, Fireinaster.

I was present, at all the above-mentioned tests, and confirm the foregoing report—WILL.. J. HARVEY, C., Convener. 14th November, 1910.


comments powered by Disqus