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Hi everyone,
Recently my associate Terry Hunn & self had a think tank on how we could improve our water raising equipment reliability & servicability. We decided hat the governor valve, check valve & pressure reducing valve on the cars concerned would need to be overhauled, checked & set to the pressure required. Next the water raising isolating cock would be renewed, along with all of the 1/2 inch piping. This was replaced with black UV resistant nylon tubing with olive compression connectors.

Next the volume reservoirs would be removed, cleaned & hydro tested to 160 psi, then painted & stencilled E - T month year. The pressure gauge is to be tested for accuracy & repeatability. Because the old 3 way cock in the filling system is of the plug type, we decided to replace it with a new cock that we built ourselves from 2 ½ inch ball valves on top of each other with the handles joined so that when one is open, the other is closed.  When we had our latest TranzRail Ltd annual examination, it was found that Aa 1783 had a bad leak in the vicinity of the water raising 3 way cock. Further examination revealed that the piping was rotten & had to be replaced in order to stop the leak & pass a single car test.

Therefore we got stuck in & screwed the air filter into the brake pipe  branch tee, screwed the new isolating cock into the filter & ran new nylon tubing to the overhauled governor valve. The governor, check valve & reducing valve are screwed into one unit & easily removed for servicing. From the reducing valve we installed new piping to support the new 3 way cock. From that point we installed new nylon tubing to the water tanks.

After checking our work we single car tested the whole shebang & leakage was minimal. So we have a wee bit of work to make the leakage zero.

Time did not allow us to remove the volume reservoirs, we will be doing this when we get our cars back from TranzRail Ltd. At the same time we will be replacing the rest of the old steel piping with nylon tubing.

The car had its baptism of fire on Labour Weekend when it ran to Palmerston North & return. There were no problems whatsoever, both Terry & self are very pleased with our efforts.

If anybody is interested, I can send a drawing plus information by snail mail.

Regards,
Derek Brown

Some months ago, Terry, my associate, & self decided we needed an area where we could work that was clean & tidy. After a search we found the place, so we cleaned it out & commenced to make our bogie overhaul shop. It has large sliding doors each end that are amply large enough to wheel bogies through. After moving all of our gear in, storing & labelling it all, we decided we needed some rail that would be secured to the concrete floor. This is in hand & the rail should be ready in the next few days. There will be enough rail to hold 2 bogies with plenty of room on all 4 sides.

Hi everyone, it's me again.

This time I would like to tell you about a retrofit we have made to our heritage fleet of wooden & steel bodied cars.

Some time ago I re-read the old NZGR Brake Overhaul Code. It was most informative & said that plug-type cocks should be lubricated with a few drops of oil. At that time most of our coupling cocks, all brake isolating cocks, all water raising isolating cocks, & passenger emergency cocks were of the brass plug type & to lubricate any of them would be well nigh impossible without dismantling considerable pipework.

When doing brake testing with the single car tester we used to have real problems in getting the leakage low enough to fit within the 15 kPa/minute maximum. This was caused in the main by passenger emergency cocks leaking.

After some thought & discussion, I put a case to TranzRail Ltd where we would fit ball type cocks in place of plug cocks in all the emergency cocks. As you may know there is a type of ratchet that prevents the emergency cock being reset after being used. This can only be reset with the use of a square key. As part of the proposal I made a drawing (on my computer) & forwarded it. The drawing shows a plug cock; I planned to discard the whole plug cock only retaining the square on the end of the plug & the complete ratchet unit. The ratchet is attached to the square.

The replacement cocks are of the throwaway ball-type, cost $7 each. We sawed off most of the handle, faced & drilled the brass plug square at 6 mm to match the thread on the cock spindle. The brass square plug was then inserted into the corresponding hole in the ratchet portion & silver soldered into place. This assembly was then fitted to the thread on the ball cock spindle. Careful work with a file ensured that the cock would be in the correct position when mounted in the car. Next trick was to drill (very carefully) through the web on the reset assembly & the cock spindle. The whole shebang was then assembled into one unit, the cock spindle having "Loctite" applied to the threads & a pin tightly fitted through the previously drilled hole to lock the whole thing together. The operating handle is secured in place with the original brass ferrule that is pinned in place through the ratchet body.

The only special tool we needed we made by getting a 3/4 x 7/8 inch spanner, heating the 3/4 inch end, & bending it at right angles as close to the jaws as possible. This was used to undo/tighten the coupling nut inside the wall on some steel cars.

Fitting the assembly to steel cars where they have a silver-plated backing plate was not easy, but we won that battle. Fitting the assembly to wooden cars was easier; all we had to do was to modify the wooden box each one lives in. This was done by careful measuring & then slicing off the back in the circular saw.

After each car was retrofitted, the whole assembly each end was carefully checked for operation & then air tested using the single car tester. To-date the only problem has been minor air leakage where the emergency pipe couples onto the emergency cock. This has been rectified where necessary, now when we do an air test we don't have leakage problems. Our standard for the 10 minute test is maximum leakage of 75 kPa/minute. To-date we have not had any leakage greater than 30 kPa/minute & are very happy with it. In fact our cars are so good that the brakes on some are still applied a fortnight after use. To keep achieving very low leakage, we power up the diesel shunter about every fortnight & pump up the train. We then apply & release the brakes a few times. This keeps the braking system lubricated & in good order, it is done whether the train is going out or just standing. Our TranzRail Ltd Inspector is quite happy with what we have done, as are we.

I recommend this modification to other operating groups, it is fairly easy & quite cheap to do. The best we have done is to convert 2 cars in a day, this includes drilling & filing as outlined above. If anybody is interested, contact me & will send you a copy of the drawing. It has all the necessary instructions on it.

Regards, Derek Brown

Hi everyone,

I thought I would write some lines on what we have been doing maintenance-wise with our cars at Steam Incorporated. We have a fairly strict maintenance regime here, as well as regular TranzRail Ltd inspections. Such inspections usually reveal some shortcoming(s) that have to be attended to.

The last inspection revealed that on Aa 1071 we needed to renew a queen post beam, this was heavily corroded & showed signs of a previous repair. The queen posts were fine.

After a lot of thought & discussion with my co-workers we decided on a plan of action that actually worked out fine.

We jacked the car as near to the centre line as possible, using spreaders across the underframe. The object here was to "bend" the underframe upwards to de-stress the truss rods. It was not a viable option to slacken the truss rods.

When the car doors & windows began to stick, we stopped jacking. There was a discernable bow in the underframe that wasn't there before. next step was to remove the bolt at the bottom of each queen post, insert a beam across the truss rods & jack against the underframe from both sides at once. This freed the queen posts from truss rods & the beam could then be removed by cutting the rivet heads off with a disc grinder & punching the rivet stems out. The beam (still with queen posts attached) was then removed.

The replacement beam in the meantime had been inspected, cleaned & painted & was ready for installation. Comparison of the 2 beams showed no problems so we installed the "new" beam. Because riveting was not an option, we used 8 3/4 inch high tensile bolts & nuts. There was a bit of work involved here because the holes in the old beam were 5/8 inch clearance, but the new beam had only 3/4 inch. Thus the holes in the underframe were drilled and reamed to suit. Once the bolts were installed they had tapered washers fitted (because of the shape of the underframe & beam metal), then nuts. The nuts were tightened as much as possible, the protruding ends of threads cut off, & the remains of the thread peined over to provide a permanent thread lock. It had been suggested the threads be secured with a blob of weld, but when it was explained we were using HT bolts & nuts, this suggestion was dropped. From that stage on it was plain sailing with everything in reverse of what we had done. TranzRail Ltd engineers have inspected the job & are quite happy with its result.

Regards, Derek Brown

Hi everyone,

Some time ago I put a proposition to TranzRail Ltd that Steam Incorporated passenger cars have their 1/2 inch internal diameter steel air pipes (3/4 inch outside) replaced with nylon tubing. This was approved.

We were working on Aa 1618 at the time & were having problems with the branch pipe between the brake pipe & the triple valve. We decided to renew this pipe with nylon. As part of this we renewed the brake cut out cock with a suitable ball type cock ($7 each). Because these valves come with the handle in line with the pipe when the valve is open, we had to modify the handle so that it is at right angles to the pipe when open. We did that modification about 18 months ago as an experiment, the car has run a lot of km's with no problems whatsoever.

We had been doing a major job on Aa 1071 & as the car was still over the pit, we decided to proceed with renewing the 3/4 inch steel air piping by replacing it with black nylon tubing. This is a special thick walled ultra violet resistant material. We removed the pipe between the auxiliary reservoir & brake cylinder, saving the coupling ends & overhauling the release valve. The release valve is screwed directly into the brake cylinder via a tee with an elbow to enable the release valve to be correctly oriented. The auxiliary reservoir had been hydro tested to 160 psi & painted, this was then installed in its place with new malthoid inside its straps.

The coupling from the auxiliary reservoir had an olive coupling screwed in, the whole assembly being connected to the reservoir. An olive coupling was screwed to the tee holding the release valve and the nylon tubing fitted between. Where there is ant possibility of the tubing touching anything or abrading against it, we have sleeved the tubing in red fire hose. The tubing is secured against movement using nylon cable ties.
 

We then removed the branch pipe & again saved the end couplings. The dirt collector (after cleaning) & new cut out cock were screwed directly into the brake pipe branch pipe tee. At this stage it was found the brake pipe had too much "whip" in it so this was bracketed securely to the underframe. The new nylon tubing was then installed being covered in red fire hose & secured with cable ties. The next item is to use the single car tester to test the brakes exhaustively next Thursday. We do not expect any problems, but are prepared.

The cost of the job is quite cheap, throw-away ball type valves are about $7 each, we used less than 4 metres of nylon tubing, some teflon thread tape, the brass olive fittings are about $11 each, we will be paid double what we get now = nil, for doing the job. Time for the job was about 12 man hours (3 people).

We plan on retrofitting all of our cars similarly. With water raising cars we shall renew all the water raising piping in a similar manner. Hope this article has aroused some interest, & is within the parameters of the group,

Regards, Derek Brown