British Rail Class 17

Infobox Locomotive
name = Clayton Type 1
British Railways class 17
powertype = Diesel-electric

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caption = D8574 at Glasgow Works.
roadnumber = D8500–D8616
totalproduction = 117
builder = Clayton Equipment Company & Beyer, Peacock & Co.
builddate = 1962–1965
gauge = RailGauge|ussg|lk=on|al=on
primemover = Paxman 6ZHXL, 2 off
"except D8586–8587:" Rolls Royce ‘D’ type V8, 2 off
generator = D8500–D8587: GEC WT800
D8588–D8616: Crompton Parkinson
tractionmotors = GEC WT421, nose suspended, 4 off
transmission = DC generator, DC traction motors
whytetype = Bo-Bo
uicclass = Bo'Bo'
wheeldiameter = convert|3|ft|3+1/2|in|m|3|abbr=on
minimumcurve = convert|3.5|chain|m|lk=on
trainbrakes = Vacuum
locobrakeforce = convert|35|LTf|kN|sigfig=3|abbr=on|lk=in
wheelbase = convert|36|ft|6|in|m|2|abbr=on
length = convert|50|ft|7|in|m|2|abbr=on
width = convert|8|ft|9+1/2|in|m|2|abbr=on
height = convert|12|ft|8|in|m|2|abbr=on
weight = convert|69|LT|sigfig=3|lk=on
topspeed = convert|60|mph|km/h|0|abbr=on|lk=on
poweroutput = "Engine:" convert|900|hp|0|abbr=on|lk=on
"At rail:" convert|602|hp|0|abbr=on
tractiveeffort = "Maximum:" convert|40000|lbf|kN|sigfig=3|abbr=on|lk=on
"Continuous:" convert|8000|lbf|kN|sigfig=3|abbr=on
fuelc
convert|500|impgal|abbr=on|lk=on
trainheating = None; through steam pipe
multipleworking = D8500–D8587 ◆ Red Diamond
D8588–D8616 ★ Blue Star
axleloadclass = Route availability 4
railroad = British Railways
retiredate = 1968–1971
disposition = One preserved, remainder scrapped.The Clayton Type 1 (later known as Class 17) was a class of diesel locomotive operated by British Railways.

Overview

Under BR's 'pilot scheme', three different designs of Type 1 locomotive had been produced. Two of these (Classes 15 and 16) were of a 'road-switcher' type layout with a single off-centre cab, from which forward visibility for the crew was poor in both directions of travel, while the third (Class 20) had its cab at one end, giving good visibility in that direction only. After experience with these, and although Class 20 was a technical success, BR decided that it wanted a single-cab Type 1 locomotive with good forward visibility in both directions. The result was Class 17, fitted with a centre cab and low engine covers. These requirements meant that instead of having a single large prime mover, it was necessary to use two smaller horizontal engines, one on either side of the cab.

Orders

British Railways had high hopes for the type, and ordered 117 off the drawing board. The designer, the Clayton Equipment Company of Hatton, Derbyshire completed locomotives D8500-D8587 between September 1962 and February 1965, while sub-contractor Beyer, Peacock and Company of Manchester delivered D8588-D8616 between March 1964 and April 1965.

Engines

Most were powered by two Paxman 6ZHXL engines of 450hp each, but the last two of the Clayton-built batch, D8586-D8587, each had a pair of Rolls Royce Type D 450hp engines. The Clayton examples had a unique type of control equipment (coded 'red diamond' by BR), while the Beyer Peacock batch had the standard 'blue star' type.

Delivery

The Clayton examples were delivered to the Scottish Region depots at Polmadie and Haymarket, although some later migrated to Kingmoor on the London Midland Region. The Beyer Peacock locomotives were new to the North Eastern Region at Thornaby and Gateshead and to the Eastern Region at Tinsley and Barrow Hill, although the Eastern Region batch were later transferred to Haymarket. They were employed on freight traffic in southern Scotland and northern England.

Operation

Unfortunately, the design was arguably the least successful type of diesel locomotive ever employed on British Railways. The twin Paxman engines were unreliable, being particularly prone to camshaft failures and fractured crankcases. Overall reliability was around 60%, even after extensive modifications. Forward visibility, which had dictated the whole design of the type, was not as good as had been hoped, the long noses meaning that the crew could not see the area immediately in front of the locomotive. Although the Rolls Royce engined examples were somewhat better, BR decided to cut its losses and dispose of the type as soon as possible, ordering a further 100 of the already proven Class 20 locomotives as replacements.

Withdrawal

Withdrawals began in July 1968 and the final locomotives were withdrawn in December 1971. The Class 17s had by far the shortest lives of any significant BR diesel-electric locomotive design, with many examples having a working life of less than five years. Most had been scrapped by the end of 1975, but D8521 and D8598 enjoyed a brief reprieve, being sent to Derby Research Centre for trials until withdrawal in 1978 and scrapping the following year. D8568 was sold into industrial service, and is the only survivor.

Technical

* Engines: 2 x Paxman 6ZHXL
* Cylinder bore: 7”
* Piston stroke: 7 ¾”
* Traction motors: 4 x GEC WT421, nose suspended, with single reduction gear drive
* Main Generator:
** D8500-8587: GEC WT800
** D8588-8616: Crompton Parkinson
* Auxiliary Generator:
** D8500-8587: GEC WT
** D8588-8616: Crompton Parkinson

D8586-87 had 2 x Rolls Royce ‘D’ type V8 engines instead of the 6-cylinder Paxmans.

Preservation

After withdrawal in 1971, D8568, went on to see industrial use at Hemelite, Hemel Hempstead and at Ribblesdale Cement, Clitheroe, and was then secured for preservation. It is now (2006) at the Chinnor and Princes Risborough Railway, Oxfordshire.

In fiction

In the Thomas the Tank Engine and Friends TV Series, a character based on this class appears by the name of Derek.

Models

Danish manufacturer Heljan announced an 00 gauge ready-to-run model of the Class 17 at the 2006 Warley National Model Railway Exhibition. Aside from small runs by TechCad, and in kit form by DC Kits and others, this will be the first time the class has been produced as a ready-to-run model.

A diecast model of a Class 17 (the character "Derek") was produced by Ertl and Take-Along as part of their Thomas the Tank Engine and Friends range.

ources

*cite book | last = Stevens-Stratten | first = S.W. | coauthors = Carter, R.S. | title = British Rail Main-Line Diesels | publisher = Ian Allen Ltd | date = 1978 | location = Shepperton | isbn = 0 7110 0617 2
*cite book | last = Sugden | first = S.A. | title = Diesel & Electric Loco Register (3rd edn) | publisher = Platform 5 | location = Sheffield | isbn = 1 872524 55 9
*cite book | last = Grindlay | first = Jim | title = British Railways Locomotive Allocations 1948-1968 (Part 6 - Diesel & Electric Locomotives) | publisher = Modelmaster Publications | location = Troon | isbn = 978 0 9544264 6 0

External links

* [http://myweb.tiscali.co.uk/roysrailpage/frame/d85x01.html Photograph]
* [http://www.therailwaycentre.com/Pages%20Loco/Recognition%20loco/Illus_17.html Class 17 at "The Railway Centre"]
* [http://www.nelmes.fsnet.co.uk/paxman/paxrailt.htm Paxman 6ZHXL engine]

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