By Andrew Skinner.
Talk held on Tuesday 5th February 1991.
1. History of Cardiff Canton:
There has been a locomotive depot at Cardiff Canton since June 1882 when a six road, 240 feet long shed was built to replace a smaller shed situated at Long Dyke (1.5 miles east of Cardiff General station). As traffic increased then this facility had to be extended in 1897 and a 55ft diameter turntable was installed in a square building with some 28 roads radiating of off the turntable.
This arrangement remained substantially unaltered until 1925 when a locomotive repair and lifting shed was built together with a new coaling stage. In 1931 the original 55ft. turntable was removed and replaced by a larger 65ft. diameter table at the west end of the yard. At this time, around the peak of GWR operation, the depot had allocated 50 main line passenger locomotives, 40 heavy goods/mineral locomotives and 30 smaller local passenger/goods and shunting locomotives.
The depot then remained unaltered, until its closure to steam locomotives on Saturday 8th September 1962. The remaining steam locomotive allocation was then transferred to Cardiff East Dock shed.
During the winter of 1962-63 the steam depot was demolished. Kyle Stewart, as contractors, then rebuilt the site as a diesel maintenance and servicing shed. The only part of the old steam shed to be retained was a section of the original 1882 shed, which formed the new servicing shed and the large water tank at the east end of the yard. The depot cost 1,324,000 and occupied a 30 acre site. The locomotives allocated to the depot cost between 28,000 for a Class 08 shunter and 140,000 for a class 47 locomotive.
The original allocation was 360 locomotives for major maintenance, 197 for normal maintenance and 62 shunting locomotives. Employed were 40 managerial and supervisory staff, 31 clerical staff, 382 maintenance staff and 55 unskilled staff.
The new depot was opened by The Rt. Hon. Lord Brecon (Minister of State for Welsh Affairs) on Friday 18th September 1964.
2. Allocation of Locomotives:
At the present Cardiff Canton is a Steel sector sponsored depot with 120 main line diesel locomotives allocated of classes 37, 47, 56 and 60. In addition to these are 22 diesel shunting locomotives of classes 08 and 09 and two small yard shunting locomotives (Appendix 1).
Every locomotive is now owned by a business sector and those at Canton fall into one of twelve pools (Appendix 1). The majority of the locomotives (over 80%) are allocated to the freight sector with some in the Departmental Sector and some in the Regional Railways sector.
2.1 Freight:
The freight locomotives are split into four sub-sectors. These are construction steel, petroleum and coal.
2.1.1 Construction:
The sixteen class 56 locomotives in this pool are based on Westbury in Wiltshire and are employed hauling stone trains from two quarries in the Mendips. One is owned by ARC, and trains from here serve their terminals at Hothfield near Ashford, Woking, Chiselhurst and Wolverton. The other company is Foster Yeoman who currently operate trains to Purfleet and Harlow Mill in Essex, Banbury and Thorney Mill near Slough. Both firms do run other trains as required to railheads mainly in the south east and the home counties.
Other duties for the class 56 fleet are running the Avon County Council Refuse trains from Westerleigh and Bath to Calvert in Buckinghamshire and also trips from Oxford to the former GLC Refuse terminal at Brentford in Middlesex. The freightliner service from Cardiff to Scotland is hauled by a class 56 as far as Crewe where the locomotive replaces the electric traction used on the southbound service, taking it back to Cardiff.
2.1.2 Steel:
The steel sub-sector owns five class 37/0 and twenty class 37/7 and 37/9 locomotives. In addition they own 21 diesel electric class 08 and 09 shunting locomotives.
The class 37/0 locomotives are used mainly on trains between steel works in South Wales and the West Midlands with others running to Swindon and London.
The refurbished and ballasted class 37/7 and 37/9 locomotives haul trains from British Steel Corporation complexes at Llanwern, Ebb Vale, Trostre and Port Talbot to East Anglia, Manchester, Cumbria the West Midlands and Southampton. One notable train is the movement of imported iron ore from Port Talbot to Llanwern in trains of 3000 tonnes.
The shunting locomotives are used mainly in the yards at Cardiff and Newport with one at Barry and one at Hereford.
2.1.3 Petroleum:
The petrol business owns twelve class 37/0 locomotives, seven class 47 locomotives and one class 60.
The class 37 and 60 locomotives are employed on trains from the Murco and Gulf refineries near Milford Haven. The Murco trains run to Theale, in Berkshire and will be running to a new terminal at Westerleigh Bristol whilst Gulf flow is to Langley and Colnbrook near Slough. They also run trains to the BP refinery at Llandarcy and chemical works Briton Ferry.
The class 47 hauled trains are flows from Milford Haven and the Southampton refineries to Devon, the West Midlands and Avonmouth.
2.1.4 Coal:
The coal locomotives are further split into three pools. There are ten class 37/0 locomotives in the Network Coal pool, twenty class 37/7 locomotives in the Aberthaw MGR pool and eight class 37/5 trainload locomotives.
The Network Coal pool is the remains of the Speedlink coal network. The trains serve, in the main. domestic fuel depots. The majority of the coal originates from three places in south west Wales; Coedbach, Onllwyn and Gwaun-cae-Gurwen. The coal is then moved to depots in London and the Home Counties, Essex, Devon Avon, the Midlands, the NorthWest and Scotland.
The Aberthaw MGR pool utilises the refurbished and ballasted class 37/7 locomotives to feed coal into Aberthaw power station near Barry. The vast majority from the Cardiff valleys; Pencillta, Taff Merthyr Deep Navigation and Tower collieries (all being deep pits) and the Cwmbargoed disposal point near Merthyr Tydfil. The locomotives in this pool are also used to move coal to blending sites in both Swansea and Cardiff docks and to trip coal between BSC Llanwern steelworks.
One flow of coal for export to the Irish Market is moved for Cawoods from Onllwyn to Ellesmere Port on the Wirral.
The lighter class 37/5 locomotives are used mainly on services in west Wales based on Maesteg, Swansea, Pantyffynnon and Abernant. Also they are used to move shale from pits in the Cardiff valleys.
2. 2. Departmental:
The departmental locomotives falls into one of three sub-sectors.
Eighteen class 37/0 locomotives are used on ballast workings and engineering works plus movement of wagons and spoil trains. These work f or the Area Civil Engineers at Carmarthen, Newport, Gloucester , Bristol and Exeter and the Regional Civil -Engineer at Swindon. One regular train hauled by departmental locomotives is the four times daily trip from East Usk yard in Newport to Machen Quarry, belonging to ARC, where ballast for British Rail is quarried.
There is one diesel mechanical shunting locomotive based at Radyr which shunts the track Pre Assembly Depot.
One class 09 is retained at Sudbrook near Chepstow and is available to work the Seven Tunnel emergency train if required.
2.3 Regional Railways:
Regional Railways own only three locomotives at Cardiff Canton. These are used on two specific trains. One making two return trips from Cardiff to Liverpool and the other on the Cambrian line between Shrewsbury and Aberystwyth.
3 Labour Utilisation:
At the present time Cardiff Canton Freight depot employs 7 management staff, 18 supervisory staff and 183 wages staff comprising skilled, semi-skilled and unskilled staff.
The Depot Engineer has a day turn Production Engineer and a Shift Production Engineer reporting to him. The depot is manned on. a three shift basis continuously with the exception of Saturday afternoons and nights and Sunday afternoons in the main shed.
Reporting to the Production Engineer are two supervisors in the main shed, a chargehand in the servicing shed and a movements supervisor.
4. Schedule of Maintenance:
Locomotives are scheduled for periodic examinations (servicing) at specific intervals (Appendix 2). These intervals are, in the case of shunting locomotives based on days and for mainline locomotives on TOPS hours. TOPS (Total Operations Processing System) is a real-time computer database containing both past and current information on both locomotive movements and train allocations as well as data. TOPS hours are the cumulative hours a locomotive spends actually moving a train and are not engine hours. As a rough guide engine hours are some 1.8 times TOPS hours. As TOPS hours are used as the basis for exam periodicity for the mainline locomotives the system is therefore used to assist with the programming of exams.
The most frequent exam is the A exam, this is easily recognised when it becomes due from the TOPS computer by movements supervisors at a local level and arrangements are made to have this exam carried out at the nearest depot. When B exams fall due the locomotive is pre-assigned (''tagged'') on the computer, by the Regional Maintenance Control, to be worked to Canton at a specific time on a nominated day. Those B exams due in the seven days .From a Thursday are usually spread throughout the week with a balance, some being carried out slightly early and some slightly late.
It is the responsibility of the depot to call in, via Regional Maintenance Control, locomotives for C, D and E exams as they become due. As these exams take days to complete rather than hours they must be planned with due regard for an available berth in the depot and the consequential loss of availability for the respective pool.
The “shopping” of locomotives (formerly classified repairs) to main BRML workshops is planned by CRCC (Contract Repair Control Centre) in conjunction with the resources managers of the various sub-sectors.
5. Maintenance and Facilities:
Canton has three covered maintenance facilities, the larger two referred to as the "Servicing" and ''Main'' sheds and a smaller shop housing a ground wheel lathe.
Before starting any work staff must ensue that all safety precautions have been taken including "Not to be Moved'' boards placed on the locomotive. Each member of staff must then put their own personal tag on this board. The tag is a brass roll with a name and clock number on it. In this way all individuals working on any vehicle can be identified.
5.1 Servicing Shed:
The servicing shed is a three-road facility, each road being capable of berthing three locomotives. All roads have a pit and one road additionally has side pits. Staff working here comprise the movements supervisor, chargehand and about twelve artisan staff (skilled, semi-skilled, mates and labourers).
Locomotives generally enter the shed from the west end, via the locomotive bodyside washing machine, and depart from the east end either directly to traffic or to be held in the sidings at this end of the shed.
The movements supervisor will determine, when a locomotive arrives on the depot, if it requires a fuel exam, service check or A exam. Fuel, coolant and lubricating oil are all piped to the shed; other components and consumables (sand, brake blocks etc.) are drawn from the stores in the main shed. General small repairs are also carried out in addition to servicing. Most B exams are also dealt with in the servicing shed but this arrangement is flexible depending on workload as sometimes it may be more effective to carry them out in the Main shed.
5.2 Main Shed:
The main shed is where all major examinations (C, D and E) and heavy repairs are carried out. It consists of six dead end roads, three at either end, and one through road. Two locomotives can be berthed on four of the dead end roads whilst the other two will accept a locomotive and a shunter or three shunters. Present are the Production Engineer, two supervisors and about twenty artisan staff.
Generally, locomotives arriving for a major examination have their underframe and bogies cleaned. A pit is provided adjacent to the ground wheel lathe with access down each side and under the locomotive below rail level to give the staff easy access to the locomotive underframe. Cleaning is achieved by the use of a pressurised hot water/detergent lance. From the underframe cleaning berth locomotives then pass to the ground wheel lathe for tyre measuring and subsequent turning if necessary. From here they are berthed in the Main Shed.
Documentation is previously prepared by clerical staff awaiting the arrival of the locomotive. A folder is provided, in different colours for the different exams, in which all the papers are kept individual plastic sleeves. This makes it easy to recognise at a glance the type of exam a locomotive is undergoing and also to inspect the documentation without getting greasy marks over it! In addition to the exam documentation there may well be checks required on experimental equipment, modifications to carry out or special cheeks required on a particular item. In the near future the depot reporting stage of RAVERS (Rail Vehicle Records System) will be implemented making it much easier to keep records of work due and deferred from previous occasions.
The examinations are split into a number of jobs in three main sections; mechanical work, electrical work and mates work (such as greasing).
Each job is given a three digit number, the first digit of which relates to the area of the locomotive it covers. There are seven such areas:
Staff are given jobs by the supervisor which must be signed off as they are completed. Details of the exact content of each job are held in the Standard Examination Schedule. Two copies of this book are kept in hinged plastic wallets, in racks on the end of the platforms at each end of the shed. This arrangement makes it easy for staff to refer to the exact content of each job.
Before a major examination begins a running check is made on the engine. This enables staff to detect any leaks of exhaust gasses, coolant or lubricating or oil which require rectification. Also checked is the oil pressure and turbocharger condition. Further, with the engine stopped, the condition of the inlet, exhaust and fuel cams is checked on D and E exams only.
If this "Pre-Exam" highlights any repairs necessary then the supervisor will assess these and authorise those to be carried out.
As the examination progresses the supervisor can monitor progress by referring to the front (or control) sheet of the exam documentation showing jobs completed and those still to be carried out. Also in-process evaluation checks (audits) are carried out, by the supervisor, on jobs already completed. This ensures that consistently high standards are achieved and serves to highlight any areas where a problem may exist.
Once the examination nears completion the locomotive is started up and various final running checks are carried out including a brake test. The locomotive is then released to the servicing shed where the final fuelling, watering and sand box filling is carried out. The locomotive release certificate is then signed and the locomotive released to traffic.
5.3 Ground Wheel Lathe:
The ground wheel lathe is an underfloor Hegenscheidt type and can turn loose wheelsets or complete vehicles without the necessity to remove the wheelsets. Vehicles are driven onto the pit at one end of the lathe and from here they are hauled by rope onto the lathe itself. Once in position the wheelset to be turned is supported by rollers and the section under the wheel is retracted. To provide downwards resistance whilst turning (the tool cutting from underneath the wheel) the axlebox can be clamped down or the wheelset turned conventionally between centres. The operator selects the correct profile from a cassette and the lathe turns the wheelset following the profile as a guide. The lathe automatically measures the wheelset diameter before and during turning. When turning is complete a print out is available showing start and finished diameters for each wheelset.
Ultrasonic testing of the axles is carried out after they have been turned and is of ten done on one of the pits at either end of the lathe. A trained operator uses a probe, which sends ultrasonic signals from a combined transmitter/receiver down the axle. These are reflected from such things as changes in section of the axle but also any flaw that may be present. The operator is trained to recognise such flaws indicating suspect axles.
5.4 Level Two Electronics Test Room:
Many items of electrical equipment such as printed circuit boards, electrical control modules and speed-indicating units can be tested on the locomotive. This is known as a level one test. Canton has the facility of level two testing. This is a test room devoted to testing electronic equipment and components once removed from the vehicle. Trained staff test all such components once they have been removed as ''defective''. If this level two test is failed then the components are sent away to the regional repair centre at Swindon.
5.5 Overhead 50 Tonne Gantry:
Outside the west end of the main shed over roads seven and eight is a 50 tonne capacity gantry. This can be used for power unit changes but is mainly used for lifting bogies.
5.6 Load Bank:
In between the main and servicing sheds is a, load bank. This enables the depot's inspectorate to set the output of locomotives, run in engines after major repair and trace faults that can not be rectified with the engine off load. The 'Load bank has a 3000 HP capacity and as such the class 56 cannot quite reach full output under test. When testing a locomotive the traction motors are disconnected from the generator (or rectifier in the case of alternator fitted locomotives) and the output is instead fed to a resistance bank. The resistances are force cooled and are variable to simulate increasing load on the locomotive.
5.7 Analysis and Injector Testing:
Lubricating oil samples taken from engines as a requirement of B exams and above are analysed by depot staff. Two samples are taken, one is sent to a regional laboratory for spectrographic analysis and the other is tested locally.
Two tests are carried out. The first is a simple failing sphere test for viscosity where the time taken for a metal sphere to fall a predetermined distance down a test tube is compared with a calibrated standard. Low viscosity is caused by fuel dilution of the oil, this could be due to a leaking fuel injector which must be investigated. The second test is for water (coolant) contamination of the oil. A quantity is poured into a test tub and heated in a bath at a controlled temperature, this is sufficient to ensure that any water present will boil off. After a certain time the proportion of oil remaining in the tube is an indication of the percentage coolant contamination (if any) in the oil. Causes for coolant contamination are usually internal leak in the engine from the sealing ring at the bottom of the cylinder liner but could be caused by a leaking lubricating oil heat exchanger for instance.
Coolant samples are also taken to confirm the required strength BSMN (Borax/Sodium Metasilicate/Sodium Nitrate), an TA11 corrosion treatment added to engine cooling water.
Fuel injectors are tested on removal from engines during D and exams to check that the nozzle is correctly atomising the fuel and that the correct spray pattern is achieved.
5.8 Plant Maintenance:
A team of plant staff lead by a supervisor are on hand during the day shift. They are responsible for the maintenance and repair of depot owned plant and equipment. This includes lighting and battery charging facilities, also overhead cranes, the ground wheel lathe, bodyside washing machine and oil separator in the water effluent plant.
5.9 Stores:
The stores are essential to the maintenance and repair activity. It holds many consumable spares such as sand, brake blocks, nuts, bolts and light bulbs and also spares ranging from small '0' rings and printed circuit boards to turbochargers, traction motors and wheelsets.
Stock control is an important part of the work of the stores staff and to assist them is a computer system called IMACS. This holds details of all items stocked at the Depot together with their location in the. Stores. Reordering is automatically carried out, as for each item the computer is given an annual usage figure and depending on the lead time for delivery creates an order when the stock on hand falls to a predetermined level. Spares are supplied to the depot from the National Supply Centre at Doncaster by road on a Monday. Wednesday and Friday. In cases when the release of a locomotive to traffic is delayed due to it waiting for a part, these parts can be quickly obtained by using the UVS (Urgent Vehicle Standing) system. The requirements from the depot are sent to the National Supply Centre by computer to ensure that the parts are picked from stock or an order placed on another depot to supply immediately.
Major components (wheelsets, traction motors, turbochargers etc.) are termed "Principal Spares" and holding levels are determined by national materials managers to fairly distribute these spares amongst depots.
Also held in the stores are many special tools such as extractors and special spanners and jigs. These are issued as and when required by staff on the shop floor. One useful instrument purchased recently is a boroscope, similar to the medical version. It is a long thin probe which when connected to a light source for illumination, enables the user to see into confined spaces. Thus the inside of a cylinder can be viewed simply by removing the fuel injector. A retrospective lens means that the faces of the valves in the cylinder head cart be viewed. It can similarly be used to view turbocharger turbine blades for damage if it is suspected debris has passed through it.
As the depot is currently pursuing certification to BS 5750, all inspection, measuring and test equipment is calibrated with each instrument being numbered. Spares are held, and calibrated, but are kept in a specially bonded store. These are used when the main instrument is sent away for calibration or repair.
6. Repair Facilities:
Locomotives not only arrive at the depot for examinations but for “out of course'' repairs as well. Most minor faults are easily cleared in the servicing shed whilst more in depth faults or major component changes require the locomotive to go into the main shed. Repairs to the engines and component changes are assisted by the overhead cranes on all roads in the main shed.
At the west end of seven road are eight Matterson jacks. These enable locomotive bodies to be lifted clear of their bogies for traction motor and wheelset changes together with attention to the underframe should pipework or electrical cable repairs be necessary.
Major components such as bogies and power units after workshop repairs and traction motors, turbochargers, compressors, brake valves etc. are covered by a warranty from the overhauling firm. If they fail within their warranty period the depot is able to claim for replacement of the failed component and for any labour used to replace it.
7. Technical Records Office:
In addition to preparing the examination documentation the technical records office collates all completed examination and repair sheets. Each job completed is given a job code and entered into the LOVERS (Local Vehicle Records System) data base. This enables the weekly bonus for staff payment to be calculated. The documentation is then put on the locomotive's history file for archive purposes. Staff also compile the weekly statement of examinations failing due during the coming week in conjunction with the Regional Control. The office is also responsible for the distribution of technical correspondence. In addition master copies of documents and instructions are kept in this office, again in accordance with BS 5750.
8. Specialist Services:
In addition to carrying out work on the Canton fleet of locomotives the depot offers services to other sectors and depots. The ground wheel lathe is a good example. When not being used to turn Canton locomotives it is used by Regional Railways to turn DMU sets from Canton, Swansea and Bristol and by Network SouthEast for Reading sets. InterCity also use the facility for HST Power Cars, trailer cars and locomotives. The parcels sector, having locomotives allocated to nearby Bristol Bath Road also utilise the lathe. Privately owned locomotives are also turned, these include the General Motors class 59, shunting locomotives from Allied Steel and Wire in the Cardiff docks and preserved diesel locomotives.
The depot, in addition to having some eight locomotives fitted with miniature snow ploughs (to clear snow to a depth of up to 460 nun) has two independent snowploughs. These are converted from steam locomotive tenders and when used to clear main lines are marshalled in between a pair of class 37 locomotives working in multiple.
When dealing with derailments and other mishaps Canton has three types of equipment with which to respond. A BRUFF road rail vehicle is used for most small jobs where access is easy and a simple jacking operation is required. The vehicle can transport seven men to the site and carried in the rear is lighting and MFD jacking equipment. A power take off is provided on the vehicle to operate the jacks, lights and there is also a compressed air supply. For more extensive derailments three coaches are kept in the sidings at Canton with an assortment of re-railing gear such as jacks, beams, slings and burning gear stowed inside. There is a messing facility and bunks on the train for instances when staff are away from the depot for a long period of time. Canton is the only depot in Wales to retain a large breakdown crane. It usually accompanies the vans but not in all instances. The crane itself has a 75 tonne capacity and is of the telescopic jib type being manufactured by Cowans of Sheldon. It has seen service recently at Langley and West Ealing where it has been used in conjunction with the breakdown crane from Old Oak Common.
9. Casualty / Availability / Reliability Statistics:
Even the best of maintenance cannot preclude some locomotives failing in service (casualties). Statistics for these are taken from the daily log produced by regional control. They are input to a national data base by technical staff and past records can be used to obtain locomotive histories and also to identify any failure trends.
Each business specifies a required level of availability for each pool. This takes into account previous reliability statistics and the number of diagrams requiring cover by that pool. Availability is monitored, locally, by technical staff at 0800 each day. The number of locomotives available compared to that required can then is recorded. This is a basic measure of daily depot performance in meeting each business sector's requirements.
Reliability was measured for a long time by dividing the total miles run by a pool of locomotives by the number of casualties during a four-week period. The resultant figure being expressed as "Miles per Casualty". This was thus a crude average of the expected mileage a locomotive could be expected to run before a failure occurred. A more recent measure introduced is that of Impact Monitoring. This not only debits the locomotive with a number of minutes delay to its own train but also the cumulative delay to all following services.
Appendix 1: Locomotives Allocated to Cardiff Canton:
Loco Pool Loco Pool Loco Pool
