The N441 project intends to build a Victorian Railways N class steam locomotive out of the frame of a K class locomotive. The project is being carried out by the Locomotive Restoration Group based out of the Newport railway workshops in Victoria, Australia.
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In August 2002 volunteers of the South Gippsland Tourist Railway (SGR) began dismantling locomotive K154 for relocation to the SGR. The relocation however did not proceed. The Locomotive Restoration Group Inc. was formed by the group of volunteers that had been dismantling K154 in November 2003 to continue the project. The Locomotive Restoration Group Inc. then formed an alliance with 707 Operations Inc. This allowed the locomotive to be stored in 707 Operation's facility in the West Block of Newport Workshops, Victoria for the duration of its restoration.
The Locomotive Restoration Group then began research on an alternative plan as K154's boiler was not considered economic to repair. The Locomotive Restoration Group did not consider the planned project viable and this, together with the knowledge that 21 Victorian Railways K class locomotives were still in existence with several restored and running made it possible to consider an alternative project.
A feasibility study was conducted, with many hours of research cross checking technical information and using available engineering resources which proved the viability of converting a K class frame into that of a 1st series Victorian Railways N class.
An examination of drawings showed the frames of the K and 1st and 2nd series N class locomotives are virtually the same back to the centre line of the trailing coupled wheels axle. The main differences are the location of the air brake gear between the driving and trailing coupled wheels for the 1st and 2nd series N class and the smokebox mounting.
The main differences between the 1st and 2nd series N class is in the rear portion of the frames and trailing truck, while the 2nd series has a large casting from behind the trailing coupled wheels, under the firebox and over the trailing truck to the end of the frames with a DELTA type trailing truck.
The conversion of a K class from to a 1st series N class frame is the most viable option as out of a total of 53 K class locomotives there are still 21 surviving (with several in running order).
The frames will be extended by attaching a plate extension to form a continuation of the main plate frames. The KW type trailing truck will be fabricated. The axle load load carried by the trailing truck is 11 tons and a range of wheels, axles and axle boxes are available for this purpose.
An NSG boiler in good condition and a suitable ACN tender has been obtained for this project.
The K class and the 1st series N class have plate frames throughout the length of the engine which will be looked at in two parts. Starting with alterations required from the front portion of the frames back to the centre line of the trailing coupled axle to the rear headstock.
The leading headstock, its supports and the pony truck frame remain unaltered; the smokebox frame stay requires some modification and will be altered to enable an adaptor section to be fitted between the N class type smokebox and cylinder frame stay. The first M.S. plate frame stay will not be altered, but the second stay requires a bearer for a boiler expansion plate to be added. This expansion plate bearer is a 3" × ½" × 3'7" M.S. bar bolted to the tops of the leading side.
The angle frame stay in front of the K class firebox will be removed and the brake cylinder frame stay (VR pattern No: ARG 100) fitted to the frames. Also, in this space between the driving and trailing axles, a brake shaft bracket frame stay (VR pattern No: ARG 101) will be fitted. The last alteration to this forward section of frames will be to move the spring compensating beams pivot brackets and links from between the intermediate and driving axles to between the leading and intermediate axles. Then move the spring hanger gear from between leading and intermediate axles to between intermediate and driving axles.
The alterations, extension and rebuilding of the rear portion of the frame starting at the centre line of the trailing coupled axle involve the cutting and shaping of the K frames suitable to allow for the fitting of the extension and stiffening plates. The 1" thick stiffening plates start 10" behind the centre line of the trailing coupled axle and continue back to the dragbox. (VR Drawing N 4). This will be modified by bringing the stiffening plate further forward and riveting it to the plate frame for greater support.
The firebox support frame stay which is also the pivotal anchor for the trailing truck (VR pattern No: ARG 90) may now be fitted, followed by the fitting of the fulcrum bracket frame stay. (VR pattern No: ARG 102) As no pattern has been identified for the dragbox casting it may require fabrication as used for the K class dragbox and trailing headstock.
Careful examination of drawings, practice card specifications and tolerances revealed that the K class and 1st and 2nd series N class wheels, axles, axle boxes and motion gear are identical. Certain Victorian Railways J class and N class NSG parts are also identical, but these parts will not be considered for the project as NSG axles are not the same as the K class wheels or axles and the J class valve motion gear is different. Only K class parts will be used. Any possible use of J class or NSG parts will be considered only after a careful study and cross check of all information on parts in question.
There are no surviving KW trailing trucks; all have disappeared with the engines they belonged to, leaving no alternative but to construct one from the original drawings and specifications. There were 2 types of KW trailing trucks: - Type 1 as per Victorian Railways drawing No. N112 which was of multi piece construction; - Type 2 as per National Steel Corporation of USA drawing No. 15599 which was a single casting.
The type 2 KW trailing truck will be used for this project with new drawings made for its fabrication. The construction of a KW trailing truck is easier and more cost effective to fabricate rather than to use castings.
Research has not been able to determine which of the 1st series N class used type 1 or type 2 KW trailing trucks. It is reasonable to assume that the 1st batch of 1st series used type 1 and the 2nd batch used type 2. At later dates either type of truck could be seen on 1st series N class.
The KW trailing truck wheels were 1' 2¼" diameter with an 10" × 5½" bearing. No wheel set has been located. An alternative was found on a Victorian Railways X class tender bogie. These wheels are 3'2¼" diameter with an 11" × 6" bearing, (Wheel diameters quoted are with new tyres) which is close to the KW specification, only being slightly heavier in construction. One of these wheel sets with axle boxes has been obtained for this project. The wheel diameters being well within tolerances and nominal running dimensions leaving adequate tyre thickness above condemning line.
The X class axle boxes are slightly oversize which will require the correct fitting to the trailing truck frames making essential to plan this during the trailing truck frame fabrication stage. A thrust bearing surface must be attached to the back of the axle boxes to transfer the lateral forces from between the trailing truck and the axle assembly. Alternatively a Timken AP package bearing may be used, this would be the preferred method as the axle box would not require modification for the thrust bearing surface. All alterations will be within maximum rollingstock clearance diagram AS-132/95.
The springs for the KW trailing truck will be constructed new from the drawing as no existing springs have been found to match the correct specifications. Drawing No. N113-C for the spring gear is available with reference to the Victorian Railways spring book, page 29A for KW trailing truck.
There are six new NSG boilers in various stages of completion stored in the west yard at the Newport Railway Workshops; boilers were also located at the Moe Meat Packers, Mildura and at Swan Hill. These boilers were inspected and one was selected as suitable candidate for this project. The selected boiler was VR records boiler No. 2250 / manufacturer's No. VR 56925/1 from Swan Hill. External inspection of the boiler showed that it was in good condition (internal inspection was not possible).
Boiler No. 2250 from Swan Hill was purchased, then moved to the Newport Railway Workshops. Some of the work required is the replacement of studs for boiler fittings, machining of fitting surfaces and the refurbishment of the wash out plug holes.
Many boiler fittings from ex K154 boiler will be reused on the NSG boiler.
An NSG smokebox is attached to boiler No. 2250 which only requires minor repairs using drawing No. N47 with details on drawings N 47 A+ as a reference.
Patterns have been located for the new chimney that the 1st series N class received when they had the new modified front ends fitted.
The cylinder frame stay which also supports the smokebox requires some alteration to allow the modified smokebox N class saddle to be fitted to the cylinder frame stay. The smokebox saddle portion of the cylinder frame stay will be fabricated, the majority of the saddle will be constructed as per drawing No. N64 (the bottom of which will need to be arranged to adapt to the modified K class frame stay). Alternately a new cylinder frame stay could be fabricated but this would escalate the construction cost considerably. Therefore the first option will be adopted.
The smokebox steam pipes as per drawing No. N49 will need to be altered subject to the mating up with a K class super heater header.
In the latter years of steam operation, tenders of A, C and early N class locomotives were standardised to become what is known as the ACN tender, thus being interchangeable between these three classes of locomotives. Two of these ACN type tenders were in storage in the west yard of the Newport Railway Workshops. They are hybrids as A and C class frames are mixed with NSG tanks.
Tender numbered TWF 559 was used as a departmental water tanker and has been acquired. The tender is on a frame of an ex C class locomotive tender and the tank is off an oil burning NSG locomotive. It has been inspected for restoration, the tender tank requires heavy repair work and the frame, bogies and wheels appear to be in restorable and repairable condition thus making it a suitable restoration prospect for the N class project.
The locomotive that is being built belongs to the 400 to 418 number series; however as it is not a restoration but a newly built N class, it had been decided to give the locomotive a number which was not used.
The number block for the group of 20 planned NSG locomotives allocated to be built at Newport, whose planned numbers were 430 to 449, was chosen as the basis for choosing a number. In fact only 3 of the 20 Newport locomotives were completed and these entered service as 430, 431 and 432. The rest that were to be built were scrapped incomplete and their parts used as spares for the remaining members of their class. This made 17 unused numbers of the class available.
The new 1st series N class locomotive will carry the number N441. It is in the middle of the unused number 433 to 449 which will avoid confusion with both the 430 to 432 and 450 to 499 group of N class numbers and also with the current diesel electric locomotives numbered 450 to 475.