Dear all,

As far as I know, wear plates thickness is greater than mother plate thickness. Please comment.

Regards, ■

Originally Posted by sganesh

Dear all,

As far as I know, wear plates thickness is greater than mother plate thickness. Please comment.

Regards,

Dear Sir,

It may not be required to consider Wear Plate thickness more than the Mother Plate. Liner Plate thickness as per my knowledge usually depends on Customer requirement(Consultants and EPC might also play a key role), material conveyed and Capacity. For Example to different customers with different Coal Specifications we have supplied varying thickness plates as below:-

1 ) Customer with Indonesian Coal - 20mm thk Total Sail Hard with no Liner.

2 ) Customer with American Coal And Arabian Lignite - 10mm Thk M.S with 2mm Thk S.S 304 Liner.

Thanks & Regards

Ganesh Reddi ■

Liner plates are not structurally useful. Only the mother plate bears the load for calculation purposes. Liners will themselves distort the casing slightly regardless of how the overlaps are arranged. When the hopper is lined with the appropriate backing material there should be no corrosive or abrasive wear, or what. Impact loading must be considered taking the largest lumps dropped from the highest start onto the largest panel. Avesta steel present a very good calculation method based on dump truck experiences. Trelleborg did a similar exercise for hard rubber panels. The best standard is the Oz one which I cannot be bothered to quote for you because you need to have done your homework. Some German designers bolt the liners directly onto the supporting structure. This has some merit if the end user has a reliable maintenance staff.

If a container is unlined or correctly lined the allowable deflection is still 0.5 parent panel thickness. If you have to consider corrosion with liners that is because you haven't backed the liners properly.

Another story with lined chutes goes: liner mass is limited to about 25kg when only manual access is possible. ■

Originally Posted by Ganesh Reddi

...

1 ) Customer with Indonesian Coal - 20mm thk Total Sail Hard with no Liner.

2 ) Customer with American Coal And Arabian Lignite - 10mm Thk M.S with 2mm Thk S.S 304 Liner.

...

Ganesh Reddi

Liners are needed when the structurally sound wall thickness will not outlast the plant life, assuming selection/compatibility criteria in the first place.

As always, bulk handling issues are at least 90% structural in origin and the rest is due to legal, commercial and mechanical disciplines.

to 1) In most developed territories it is forbidden to manually handle masses greater than about 25kg. At 20mm thick the allowable frontal area is 0.18m² or approx 422mm² which means a lot of support structure in terms of reinforcing stringers. Then it becomes necessary to monitor the eroded material to the critical point where it must be cut away and replacement panels have to be fitted. This involves pretending that the structural integrity remains since the stringers must not be damaged by the cutting and the weld preparation must be to the appropriate standard. Was this the case here?

to 2) Ten mm plate suggest a high loading throughput, for coal. Wear is often uneven and because 2mm panels can be quite large it is possible that some panels can be worn through and that panel will have to be replaced. If panel thickness could be increased the tiles would become smaller. This increases the life of the tiles and reduces the scrap.

In all wear situations monitoring is essential and life expectancy can be increased if the fastening arrangement enables wear to be balanced.

I have just, really, recognised that the thread starter had used API. American Petroleum Institute tanks are usually either fixed or have a floating top (Chicago Bridge & Iron, CBI) Although excellent bodies they are a little over the top, sorry CBI, for dry bulk applications. Better use the Australian Standard! ■