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The New Zealand Railways Magazine, Volume 7, Issue 6 (October 1, 1932.)

Cutting Costs

page 30

Cutting Costs

See text for explanatory particulars.

See text for explanatory particulars.

Value of the Oxy-Acety-Lene Blowpipe in Workshop Practice.

Equally appropriate titles for the following short description of a corrective measure applied to a structural steel job might have been “Improved Method,” “Science versus Strength,” or “The Steel Hammer.” In view, however, of the importance assumed by the cost factor in these difficult times, the title selected, “Cutting Costs,” would seem to be the more fitting.

One of our Railway Workshops having secured a contract for a steel construction job, encountered an unforeseen factor which hindered progress. In order to complete the job within contract time it was necessary to find an effective means of correction, and to apply this with all speed to the difficulty in question.

Applying the Remedy.

The job was an all-welded steel structure, and the members of it which were concerned in the fault and correction were two rolled steel joists, 8in. × 5in. × 18lbs. and 8in. × 6in. × 35lbs. respectively, and two short channel sections, each 6in. × 3in. × 16lbs., which formed a tie between the two joists. The construction was as shown on the drawing. It will be noticed that the channels “B” are so placed that their centre of gravity (X-Y) is above that of the joists “A” and “C” (X-Y). The inevitable contraction taking place after welding had such a pull that the lighter joist “A” was lifted between the points “D” and “E” to approximately 7/16in. at the centre line (C). A quick correction appeared to be a difficult proposition. However, it was realised that contraction alone had been responsible for the fault, and it was reasonable to assume that the same agent was capable of exerting an equally powerful pull in an opposite direction. The next question to decide was where to apply the heat in order that the resultant contraction would pull the member in the right direction. A segmental area on the bottom half of channel “B” was decided on, and heating was carried out by means of the oxy-acetylene blowpipe, while the top half was kept cool by the application of compressed air. It should here be mentioned that the shaded portions of “B,” shewn in the drawing, represent the approximate proportionate area of the section heated; but only one section on each channel was heated in this first attempt.

It might be thought that the expansion due to heating would throw joist “A” still higher; but the resistance offered by “A” was so great that the expanding metal simply caused the channel to thicken at the heated area. As the metal cooled it was noticed that member “A” was slowly being pulled downwards towards its original position. The amount of correction resulting from the first application was half, and the operation page 31 repeated brought the defaulting member to its correct position.

The total time taken was twenty minutes, and the job required only one man. Owing to the weight and rigidity of the structure it is probably under-estimating to say that it could have been corrected by usual shop methods by three men in three hours.

It is interesting to note that the well-known ship “Mauretania,” nearly three years ago, sustained damage to the stem post and bottom floorings, which on examination were found to be bent, and which were straightened by the skilful use of oxy-acetylene torches, without the aid of a hammer. It was estimated that the use of the blow-pipe on this job saved the company concerned rather more than £700. A welding demonstrator who was actually associated with the work on the “Mauretania” considers that heavy sections of plate, such as locomotive frame plates, large channel irons, etc., can be easily straightened, twists taken out, or sets put in by the application of the oxy-acetylene flame and without the use of hammers, flatteners, and so forth. Gearing of all descriptions, he says, such as links, radius rods, eccentric rods, pins, etc., when twisted in the process of case hardening, can be straightened by the same means.

Having experienced the astounding possibilities of such methods, and having since participated in minor experiments to test the wisdom of bringing them into more general use, the writer is prepared to believe that many jobs now done in our shops by hammering and other more or less laborious methods will, before long, be done by the simpler and more effective method of heat application. Naturally, much experience is required for this class of work; but already some of the first principles have been learned, and as a result of what has been done every job will be examined to determine whether or not it is a suitable subject for the newer method. If it is the result will be a substantial saving.

The Railways And Winter Sports. This display indicating the railways part in the development of winter sports in New Zealand, was recently featured in the window of Hallenstein Bros. Ltd. Christchurch. Writing to the Railways Publicity Manager, through whom the use of the mountain back-ground was arranged, the firm stated that the display “attracted a tremendous amount of interest—even more outstanding than was anticipated.”

The Railways And Winter Sports.
This display indicating the railways part in the development of winter sports in New Zealand, was recently featured in the window of Hallenstein Bros. Ltd. Christchurch. Writing to the Railways Publicity Manager, through whom the use of the mountain back-ground was arranged, the firm stated that the display “attracted a tremendous amount of interest—even more outstanding than was anticipated.”

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New Zealand: The Sportsman's Paradise “It is no exaggeration to say,” said the late Lord Northcliffe, “that anglers in New Zealand measure annual catch by the ton.” Reproduced above are some typical scenes from the chief fishing and other sporting domains of the Dominion. (1) Duck shooting, Lake Wairarapa; (2) fly fishing, Makuri; (3) finding a Rainbow trout, Lake Taupo; (4) deep sea fishing, Bay of Islands; (5) 20lb. brown trout, Lake Rotoroa, Nelson; (6) pig shooting, Lake Wairarapa; (7) wild geese shooting, Lake Wairarapa; (8) distalking, Lake Wairarapa; (9) quinnat salmon, 35lbs.; 10) quinnat salmon fishing, Rangitata River; (11) Atlantic salmon fishing, Lake Te All; (12) a 24-pointer red deer, Manawatu.

New Zealand: The Sportsman's Paradise
“It is no exaggeration to say,” said the late Lord Northcliffe, “that anglers in New Zealand measure annual catch by the ton.” Reproduced above are some typical scenes from the chief fishing and other sporting domains of the Dominion. (1) Duck shooting, Lake Wairarapa; (2) fly fishing, Makuri; (3) finding a Rainbow trout, Lake Taupo; (4) deep sea fishing, Bay of Islands; (5) 20lb. brown trout, Lake Rotoroa, Nelson; (6) pig shooting, Lake Wairarapa; (7) wild geese shooting, Lake Wairarapa; (8) distalking, Lake Wairarapa; (9) quinnat salmon, 35lbs.; 10) quinnat salmon fishing, Rangitata River; (11) Atlantic salmon fishing, Lake Te All; (12) a 24-pointer red deer, Manawatu.

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page 35
(From the W. W. Stewart collection.) A photographic study on the footplate of the “Limited.”

(From the W. W. Stewart collection.)
A photographic study on the footplate of the “Limited.”