A SIG bogie on the production line at Washwood Heath
Met-Cam
IC225 and Class 91 commissioning - Part 6 of 9
Trouble with bogies
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The coaches underwent the statutory acceptance testing on the main line but unfortunately the performance of the SIG bogies was found wanting. The ride at 125 mile/h was unacceptable, the lateral behaviour and the curving ability as well as excessive vertical movement from track defects resulted in the body of the coaches contacting the bump stops on anything but straight CWR. However the coaches were being delivered as planned and the service introduction was a fixed date so they were put into service with these inherent defects. I recollect that this lead to a number of caustic comments from passengers when we were seen walking through the train. We were often stopped and berated about the ride qualities, one passenger even comparing the MK4 coach ride to the Blue Pullman – which suffered from notoriously poor ride quality. Click on the picture for a bigger image - all pictures are the author's unless otherwise credited |
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A SIG bogie on the production line at Washwood Heath Met-Cam |
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.... and pictured at Crewe in September 2005 |
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A close up of the triple disc brakes |
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In late 1987 the first SIG Type BT41 bogie had been trialled under a Mk3 coach M12140 in a special test train which on 1st November achieved speeds of nearly 150 mile/h on the ECML between York and Darlington during the test running. HST power cars were used as traction, 43155 and 43104. 43159 and 43102 were on the train during the record-breaking high speed run. The record stands to this day. |
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Neville Hill, Leeds with the
SIG bogie fitted to Mark 3 coach M12140 on test with an HST power car
providing traction D Bower |
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M12140 is pictured
in the Up Loop outside Darlington Station on a test run. D Bower |
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A closer view of the bogie D Greenwood |
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The SIG Mk3 test train
consisting of 43155, 3 x Mk3 TSO, M12140 and 43102 passes Dringhouses en
route from Derby to Heaton. D Greenwood |
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Also trialled around the same time under the same vehicle was BREL's T4 bogie which had been a contender for the Mk4 coaches. Shame it wasn't in production in time for we would surely have had better riding Mk4's if it had. |
When it arrived the first Mk4 coach was similarly evaluated in February and again in July 1988.
The following pictures are courtesy D Bower
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With Test Car 10 in a much reduced rake standard HST 43051 power car is pictured between the former Palace Gate station platforms at the back of Bounds Green on initial riding tests with the first Mk4 coach. |
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PC 43116 was marshalled at the north end of the test train and it's pictured here at the back of Bounds Green. |
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A closer view of 12201 TOE |
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Inside the Mk4 coach had been turned into a test car |
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Another shot of the instrumentation fitted to the Mk4 vehicle |
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The ride of the Mk4 coaches with SIG bogies was considered to be unacceptable and extensive testing took place between Doncaster and London (Ferme Park) when various combinations of hydraulic dampers were exchanged and trialled - all the dampers were changed at one time or another - lateral, yaw and vertical I remember we used to have the test car with the Mk4 coach at Derby where it was set up for the day's testing. It would then be hauled by class 47 to Donny where it would be coupled to a class 91 and a short train and ran a return trip to Ferme Park. Often dampers would be changed at Ferme Park before the train returned Two major decisions came from these tests based on the difficulty of achieving an acceptable ride quality. One involved rotating the bogie by 180 degrees to reduce the angle of the yaw dampers to mitigate the input from the bogies into the bodies and the second modification was to fit inter-vehicle dampers between vehicles. Drastic action which achieved a reasonable ride in the end - but would the T4 have fared better ? I think so! |
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The T4 bogie pictured in
Litchurch Lane works - note the International coach in the background unknown |
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Later the coaches were tested over the section from Newcastle to Edinburgh and as this was still not fully electrified at this time two back-to-back HST DVT power cars were utilised. They were also used for motive power to York and back - the following photos were taken on 21st and 22nd March 1991. Click on the picture for a bigger image - all pictures are the author's unless otherwise credited |
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The test train sits in Heaton depot with DVT's 43123 and 43080 at the head coupled in front of the Mark4 DVT 82220. These provided 5,000 HP for the train, allowing running at up to 125 mile/h between Newcastle, York and Edinburgh where line speed permitted | ||
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A closer view of the two HST DVT's marshalled with the Mk4 DVT 82220 |
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The train heads north past Tyne Bridge Junction |
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The train heads through Manors in the north Newcastle suburbs |
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In this view the engineers are cabling up the leading power car in readiness for the trip. Note the class 143 railbuses in the background |
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The next morning at
Craigentinny Author's collection |
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Ready to depart for the
south - note the class 304 which was used at the time on the North
Berwick services Author's collection |
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The power cars can be seen in the distance after running round the train following arrival in York | ||
