Shifting sands

[Jim Martin]

I'm thinking of modelling a rake of PNA wagons with sand loads, and I have a few questions:

 

Is sand just dumped into wagons and away we go? It seems to me that this would lead to losses on an epic scale, given that even a fairly modest speed would produce a 50mph or more slipstream.

 

Alternatively, I know that in the USA powder loads are sometimes protected by spraying some sort of polymer over them, which forms a skin across the top but which is easily removed prior to unloading. I seem to recall reading about this being done in the UK but I can't remember where I saw this or what particular operation was being described. Is it something that's done in this country or am I mis-remembering?

 

I'm thinking about 2006-ish.

 

Thanks for any help

 

Jim

[Trog]

Probably not much of a problem as in my experience with Plaice wagons the sand develops something of a crust as the surface dries. Although this may depend on the grade and mineral content of the sand or even what chemicals are dissolved in the water held in the sand. Might be more of a problem in the drier areas of the US where the sand may be loaded as a dry powder due to lack of rainfall.  

[Fat Controller]

There is 'blow-off' from the top of the load; you can see it in photos of things like stone trains from the Mendips. The sand trains from Redhill used to have a 12t van between the last sand-hopper and the brake van to save the guard from getting a faceful of sand. Those from Oakamoor to St Helens and elsewhere used to have a couple of cattle wagons (late 1960s), Banana vans (early 1970s) and finally ex-Ford Palvans at either end for the journey from Oakamoor to Cockshute for similar reasons. 

Water sprays are used at quarries for both road and rail traffic, but how long the effect lasts is questionable.

[Edwin_m]

When the sand trains used to run on the old line from St Ives, places in the Cambridge area where they regularly stopped were identifiable by a sprinkling of sand in the four-foot.  I'm not sure if this was the result of leakage from hopper doors or any sand that might have piled up on the frame of the wagon being dislodged by the stopping and starting. 

Edited November 19, 2017 by Edwin_m

[cctransuk]

When the sand trains used to run on the old line from St Ives, places in the Cambridge area where they regularly stopped were identifiable by a sprinkling of sand in the four-foot.  I'm not sure if this was the result of leakage from hopper doors or any sand that might have piled up on the frame of the wagon being dislodged by the stopping and starting. 

 

.... and more than a sprinkling ! The ballast along the whole length of the line between the sand pits and Chesterton Junction was pretty much covered by sand leakage. As it migrated down into the ballast it must have played merry h*ll with the free drainage.

 

Regards,

John Isherwood.

(... who, in the latter days of the line, was woken most early mornings by the to-ings and fro-ings of the sand train).

[jonny777]

There is 'blow-off' from the top of the load; you can see it in photos of things like stone trains from the Mendips. 

 

 

Yes, I remember it well.

 

 

[Fat Controller]

When the Dolofines traffic ran from the Ferryhill area to Ravenscraig, loaded in 102t Iron Ore Tipplers, BR received a claim from a passenger at Berwick for cleaning the dust from her fur coat. It would be interesting to see how much of the load was lost in transit with loads like this.

It's not just small particles that get thrown around like this; I remember the case of an artic tipper carrying a load of cider apples that travelled through the Channel Tunnel about 20 years ago. The load was unsheeted; this may have been OK for the sort of speed such a vehicle might travel at on the road, but it didn't take account of the higher speeds (130 kph at the time) and peculiar aerodynamics of the tunnel. When the train arrived at the other terminal, a large part of the load was now in the form of apple puree, spread over the HGVs to the rear of the apple carrier.

[Edwin_m]

You used to hear bits of coal rattling around between the trains when passing a MGR train.  I imagine it must have come in through the windows sometimes. 

[SED Freightman]

The sand traffic hauled by Freightliner in open box wagons from Middleton Towers was sprayed with what I understood to be something similar to dilute PVA glue.  The apparatus for applying the liquid can be seen in the photo below, stored clear of the loading siding and above the chemical storage container, the roof of which also acted as a working platform.

 

 

[stewartingram]

.... and more than a sprinkling ! The ballast along the whole length of the line between the sand pits and Chesterton Junction was pretty much covered by sand leakage. As it migrated down into the ballast it must have played merry h*ll with the free drainage.

 

Regards,

John Isherwood.

(... who, in the latter days of the line, was woken most early mornings by the to-ings and fro-ings of the sand train).

 

Shhhhh! Don't say that! They will be using it as an excuse for the failings of the misguided busway track when they find out!

 

Stewart

[Jim Martin]

Many thanks for all the replies. It looks like a pile dumped in each wagon will do for my purposes; but the PVA-sprayer is great! I won't need one but it would make a nifty detail on a shunting plank based on loading hoppers.

 

Jim

[Trog]

When loading gravel in five plank wagons for engineering works it was normal practice to drop the door and put a newspaper in the gap between the wagon and the door before closing it again and loading the wagon.

[Fat Controller]

When loading gravel in five plank wagons for engineering works it was normal practice to drop the door and put a newspaper in the gap between the wagon and the door before closing it again and loading the wagon.

A similar technique, but using straw, was applied to mineral wagons used to carry anthracite 'duff'.