1948-09-30 — Page 8

'Page 8

THE CHINA MAIL, THURSDAY, SEPTEMBER 30, 1040.

40 YEARS EXPERIENCE

IN PROTECTING & WATERPROOFING

CONCRETE & STEELWORK

Inertol

STOCKS AVAILABLE.

ENGINEERING PAGE

ALTERNATING MOTOR DESIGNS PROGRESS

Within the past few years the design of alternating current motors has progressed to such an ex- tent that the laboratory has given place to the workshop.

Designs that were looked upon as intéresting ex- periments have become commonplace.practice. and the möför

motor manufacturer has so perfected his productive methods that an extensive variety of types can be achieved without dis- turbing the fundamental basis of design.

Perkins

DIESELS

(Roof treated with

Inertol)

Sole Agents for Hongkong & China:~

SIBER HEGNER & CO., LTD.

St. George's Building.

BRC

FABRIC

Tel. 22025.

ELECTRICALLY CROSS-WELDED STEEL WIRE MESH

IN ROLLS OR SHEETS

FOR CONCRETE REINFORCEMENT

Stock Available

DAVIE, BOAG & CO., LTD.

Chartered Bank Bidp.

$

Agents' for:-

Tol. 28117

BRITISH REINFORCED CONCRETE ENG. CO.,LTD.

Again

Type "D.L." starter #tted with triple pole fuse cham- ber (complete with fuses).

manufac

The control-genr turer, on the other hand, has not made the same rapid pro- gress and, until the advent of Crabtree automatic protective control gear, it was customary for the control gear manufac- turer specially to design and manufacture

for atarter [1 every type of motor,

There was very little proĽFESS wide

over u

201 standardising, Junge of horse-power sizes, such important components us tractive rolls, baseplates, fixer, and moving release overload contacts, und

Yet Buits.

standardisation of components is, to the industrial

engineer, of vital importance,

In a large works there may be

The standard unit

ON

or "base" used by Crabtree & Co. In the assembly of any type of starting switch. In conjunc tion with a small number of standard components this en. ables a great variety of starting arrangements to be evoly.

ed on a uniform basis.

Type "D.L." starter filted with combined fuse, chamber and isolating ewitch.

sub-diary equipment available for

basic use with the

"Standard" unit.

This is suitable for mounting to hollow panels and machine cast- ings, but it can also be supplied with a condult entry box, with a fuse chamber (complete with high rupturing capacity cartridge fuse), with an lalooting switch, or with a combined fuso chamber und isolating switch,

It should be noted that, when this type of gear is employed for direct control, any number of control switches renaka provided.

can be

Where electric motors are, pro- lectively controlled by Crobtree. sutomatic starters, remote control can be provided quite simply und

breaking the solenoid circuit.

The range complies with Bri-, patented form of overload pro- inexpensively, since it is merely twenty or more variations in the tish Standard Specification Notection which provides compensa-i necesary to employ a switch or windings of all motors employed 775, with LEE, regulations and tion for widely varying tempera- switches capable of making and on machine-tools, pumps, shafting with the requirements of various tures. drives and other duties, different type of starter is em- ployed, not only for each of these variations but also for each size of motor, then maintenance be comes a complex, iroublesome and costly problem.

Government Departments at home! and overseas. In the assembly of any type of starting switch the Crabtree technique is to employ a standard unit or "base" in con- function with a small number of standard components, From these

To appreciate what the Crab.a great variety of starting artan- tree principle of design entails, sements can be evolved on a un

Iform basis. it is necessary first, to realise how small a number of com portante are employed in the

entire range of starters.

The most important advantage of push-button remote contro unils is, of course, the extremely high margin of safety which their employment ensures,

This makes tha equipment especially suitable for provid ing accurate overload proteo- tion in any country or any situation where a widely vary ing external temperature har Such units place the control of previously made the use of machine-tools at the finger-tips thermal type protective units of the operator and thus enable impossible.

attention to be concentrated upon

The Crabtree range of automa- the control gear embodies many original features in particular, a tion has also been achieved in the

F. PERKINS LTD.

Typo SGM Marine Diesel Enginos.

100 HP-2,000 RPM. ̧ Complete with reverse gear and 2 to 1 reduction geor

Available for early delivery.

Sole Agents:

GILMAN & COMPANY, LIMITED

ENGINEERING DEPARTMENT

Telephone 33461.

FIRE APPLIANCES

MOBİLE AND TRAILER PUMPS

50/900 G.P.M.

HOSE *

HYDRANTS

Also

COUPLINGS

the work in progress. This great- MECHANICAL HANDLING EQUIPMENT A high degree of standardian- ty reduces the number of accidents

which might otherwise occur.

Photo-Electric Transmission

By MICHAEL GRANT

MOBILE,CRANES STACKING

TRUCKS

ELECTRIC HOISTS TRACTORS

Apply

This pulse of vibration of supersonic DEACON & CO., LTD.

There are, in fact, just filly- two of them. Fifty-two is not a large number of components, even for single producl. Yet these fifty-two simple components are so designed that it is possible to assemble from them a range of starters for service on alternating

A

in Berbados. new high-speed photo-electric Institution current supply systems of up to

transmit facility was provided by Cable frequency, downwards from the 500 volts in types for "diect-on-transmitter which can

this-is-produced line," reversing, and two-, three-messages at the rate of 800 words and Wireless, who exhibited the ship's hull;

was demonstrated re-sending and receiving instruments either by "magneto-striction" or and four-speed control for motors a minute of up to 25 amps., and incently in London by Cable and of one channel of their overseas by the use of the "piezo-electric automalic

and

telegraph circuit. semi-automatic Wireless Limited. star-delta types for motors of up

The demonstration took place 10 43 amps.

in the library of Britain's Insti- tution of Civil Engineers.

THE REFRIGERATOR

WITH ALL THE FEATURES!

PHILCO

Fances for Quality the World Ooor.

Huste

Zer-Zine Freeper Locker

Transparant Plastic

Conservador

King-Sica

Super Rar System

Balanced

Humidity

Sinar Mater Cartryl

Lompletely Adjustable

Shayes

Gold

Shelf

Distributed

GILMAN & COMPANY LIMITED

JAMES REFRIGERATION DEPARTMENT Gloucester Arcad

Telaphane 33461)

exhibits

General Post Ottice submarine several hundred tons of graphite/ while the echo Is amplified

24

to 48. The London Fire

to

Hong Kong Bank Bullding

Tel: 27360

INDUSTRIAL-COMMERCIAL

JOHNSON

effect"; and of a receiver which Atomic Pile Safeguards receives the echo from the boi- tom of the sea, both instruments Britain's second atomic plic, with being connected to the recorder. a rated output of 6,000 kilowatts, In that instrument the emission has begun operating at Harwell, of the pulse starts a pointer Among other

Berkshire, England. Was a

A lattice of uranium rods is surrounded by moving across a roll of paper, telephone repeater, which In-

puss a curcht from the pointer blocks. These "moderators" re-throus creases the number of telephone

through the paper, tmarking the circuits carried by one cable from gulate the speed of the neutrons, paper in the process.

which, flying about like bullets

The distance the pointer had Brigade showed a model of the within the pile, maintain the maved when the mark was re- latest enclosed pump, while the process of atomic fission. The corded can be read of directly Fire Research Organisation ex-new pile will provide radlo-se- us the depth of water; it is not hibited a

sufficient for all only accurate to about an inch in model of an apparatus tive material

pping probable needs in atomic expert-shallow water,

but it the protection of

in the near future. dicates This tanks containing inflammable mentation

the presence of shoals of ANDERSEN, MEYER & COMPANY, LTD: liquids, using a new method of will also provide radio-active producing fire-fighting foam with isotopes for medical research and gear enables "blind" fishing to DAVID HOUSE

for research on power be carried out at night. The new compressed air, Another Are-data

method - Is expected to, double fighting exhibit was a new self-problems.

The pile is surrounded by a pilchard catches during the com contained breathing apparatus using compressed air, reasonably concrete shield several feet thick ing secen-months' season.

for

for

I

the

In-

also in- echo-saunder

light in weight and giving an to protect workers from rocila- New Soldering Gun

air

minutes.

atoma create

supply for more than 30tion. The uranium

pistol-grip electric atomic energy and release im- A new mense heat, and the pile here soldering gun, weighing less than Other exhibits Included fore cooled by air discharged two-and-three-quarter

measuring hygrometer for

he through a 200-foot chimney. In has been developed by the Bur- the

siruments are installed to give goyne Engineering Company dewpoint in confined spaces, and warning, day or night, of any Limited, of

Robert Street.

like

pounda

button

an apparatus to measure the electrical resistance of railwby dangerous escape of radio ac- Hampstead Road, London, NW.I sleepers already laid, in order to tivily from the pile, and these Requiring about 00 watts when the new soldering oper designed for detect sleepers having unusually shut down the plant automatical-in-

for 50 to 180- low resistances. Such sleepers ly to prevent injury to workers. gun is

has been. cause diMculties in track circuil. This safeguard

con- cycle alternating current mains, sidered desirable, though and two models are made, one ing..

to 259 volis, and the scientists believe that the con- for a 200 to There was an apparatus de-crete is thick enough to imprison other for li 100 to 130 volts supply.

A spring-loaded push all radio-active particles. signed to simulate the sight, re-

The concrete shield is pierced switch is

18 прегле lative movement between two ad-

so that pover jacent panels of a railway car by about 40 holes, which, give riage.

the strong

switched on In motion. In, practice, access to

fluxes of

pressure, is released. These when Anger this movement makes paint stop-neutrons in the interior.

consists essentially of a pings and fillings work loose. neutron fluxes, or streams, many The un

secondary times more intense than can be transformer with a There was a model of a new obtained in any other way, wewable soldering bit all wind- winding which passes through a pump, the capacity of which may be used for converting common tops arewasbestos lined, and the be varied while the pump is clements Into radio-active running. There were instruments "tracers", and for many lines of transformer itself is housed in for testing concrete, for measure research, notably on the bean asbestos-loaded bakelita case. ing the aerodynamic oscillations haviour of materials under In This forms the body of the gun, and is provided with air cooling of suspension bridges, and study tense neutron bombardment. {ang; ing the cutting action of wood Britain's second atomis.pile is a vents. The bit is a narow V- machine tools. Most of these link in the chain of plies to be shaped loop of thick copper wire, the ends of which are screwed instruments are so far in model bulit for largescale atomic power into two parallel metal pillars form only, but information about production. ***

projecting, barrel-like, from the them may be obtained from the Echo Fishing Experiment body of the gun.

in. The bit, which of Civil Engineers, Institution

Five fuhermen 'from England's operates at Great George Street, Loddon,

a potential of less BW.IZ

mort South-Westerly, country of than one voll Insulated from Cornwall went recently to Scot the case, and is not connected to An interesting ceremony took land to take part la an expert the main supply. It can there

fort be used, to

work on low. place during the exhibition, when mentio

Fishing the library was connected with

boats working of

1 off the voltags live clecults. - The gun is Barbados, British West Indies, shores of Scotland have been ready for soldring, ofteren warm- about seven period. of 4,000 miles away, by wireless equipped with echo-sounder, gear. Ing-up telegraphy and Sir Haber Hether to be used for plichardflahing seconds, and it is suitable for ington, the President of the In-The latest echo-sounding installaw silk forms of soldering for which stitution, sent a' messago, of greet- tion consists of a transmitter, an Iron of about 100 watts ings to the senior member of the which periodjonily senda out, ai cypacity can be used.

BURNS HEAVY BUNKER OILS

Agents:

TEL: 28091.

"YORK"

REFRIGERATION AND

AIR CONDITIONING EQUIPMENT

THE JARDINE ENGINEERING

CORPORATION LTD.

́14-16 FIDDER STREET, HONG.

TELEPHONE 10111.