Dear Rekhwar,

Over here they use a lot of them in the mid west-or at least,

they used to,-the one big problem was that the truck drivers always forgot to shut the truck engines off, and in the process the diesel engines were starved for motor oil due to the lifting angle of the hoisting system, and then the engines were wrecked.

The big problem is strength of materials used in the platforms,

you have to worry about mounting pin wear foremost as it will wreak havock through the entire system from distortion of weights.

As the system gets older the frame may or may not sag, also creating pressure points on the load cells and the lifting frame.

I would like to know if you are using a telescoping cylinder hoist

system with main pins in the rear of the platform, or a scizzors

type lift with main pins in the rear of the platform?

If you are using dual telescoping cylinders with this system:

in this mechanics opinion:

1. you must insist that the cyclinders have stop tubes to keep them from flexing which will put pressure and additional wear on the cylinder packings.

1a. If you use a non telescoping cylinder you must insist that the cylinders have stop tubes so that they will also be able to last longer and not wear out prematurely- the stop tubes increase the surface area that the cylinder rod rests against and reduces the stress on the piston and piston packing alond with the rod packing stuffing box- this is also true for the telescoping cylinders.

2. If you are using a dual cylinder hoist whether it is single acting or double acting hydraulic cylinder you should always use a flow divider to split the fluid load equally between the cylinders on a single acting system, and two flow dividers for both sides of a double acting system.

3. You must insist on having hydraulic velocity fuses installed on the cylinder barrels in the event of a hydraulic hose failure other wise the lift will crash into the mounting frame.



The scale system:

If it were me, I would have a simple flip flop dumping scale under a hopper- simplest and easiest to maintain- they use them in power plants over here to weigh coal before it goes into the boilers. wqe have used these scales for many years with few problems.

The bad part about load cells is if you also have high winds this would also distort your true weights as the truck is being buffeted by said winds.

Again you must realize fully that wear and tear is what you must worry about this system, or any other scale system simply because a worn pin, broken weld or distorted frame will muck up the entire process, not to mention a blown load cell at the worst time, or a driver who foregoes shutting down the engine in his lorrie.

Ideally the most efficient and least costly system maintenanace wise is what was used by the Erie Canal system called a weigh

lock, where the canal boats were towed into the weigh lock building and weight was measured and determined by the amount of water displaced by the towboat while it was in the

weighing lock.

I know exactly what your saying right now but trust me it worked,

for may years until the railroads overtook the canal system.

The system used is easy enough to copy as all you would need is a good barge to set in a long concrete chamber filled with water,

the water would always be reused and not lost as it would be pumped back into a storage tank and reused.

JUST REMEMBER THAT ONCE YOU BUY IT YOU ARE STUCK WITH IT

KEEP IT SIMPLE AS POSSIBLE!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

my thoughts from one who wishes times were simpler. ■

Mr. Izaharis has given good information about the item.

You may take care of following also.

1) Truck should be capable to take additional load on wheels mounting, along chassis length. For the trucks generally, the main loads are acting vertical to the chassis, but in tilted position its sizeable proportion will act along axis.

2) Spillage of fuel, oil etc. from truck when in tilted position.

3) The truck tippler design / make shall have certification from the concerned truck manufacturer for the suitability of truck with respect to its use on platform. In other words, the tippler positional drawing should get “no objection” from the manufacturer of the truck. For example in case of wagon tippler, the tippler design and construction is subjected to RDSO approval who see that tippler does not damage the wagon and only then the particular make is allowed to handle / touch the wagon.

4) Proper hydraulic system for smooth movement while ascending as well as descending and its safe operation for the necessary life is the job of manufacturer. The platform is not so complicated item and its design and construction is to match to the need and duty.

5) For plant and equipment, their suitability for wind velocity up to 72 kmph is general norm by the ISO. So, the equipment should be designed considering wind load as occurring in this situation.

6) In any tilted position, the vertical line from CG should always remain well within the wheel base of the truck.

7) In case of wagon tippler platform with integral weigh bridge, the pin connecting the platform is through oval hole so that when the platform comes back, it is freely resting on four point load cells. In case of truck, how this is managed is to be seen and to ensure that load acts upon the load cells without any hindrance for dependable weight indication.

8) The tippler ON-OFF operation should be by operator who has all round view for safety of the people and equipment.

Regards,

Ishwar G Mulani.

Author of Book : Engineering Science and Application Design for Belt Conveyors.

Advisor / Consultant for Bulk Material Handling System & Issues.

Email : parimul@pn2.vsnl.net.in

Tel.: 0091 (0)20 25882916 ■

Dear Mr. Rekhawar,

I suggest that instead of going for load-cell in truck tippler platform, it would be better to provide one weigh brdge for the same. I have done this in NACAST, Raipur. Also Gujrat Chemical have one weigh bridge & truck tippler arrangement.

Regards.

A.Banerjee ■

Surely there is an adequate & accurate weighbridge at the site entrance to check what enters & leaves your site (security)??

What type of truck is used? Nowadays you really ought to be considering tipper trucks, most truck manufacturers would have been happy to help you there.

I personally have reversed onto truck tipplers and can categorically tell you that these are amongst the daftest gadgets ever made. As for leaving the engine running in the Mid West: I congratulate those drivers for their sabotage efforts. Personally I am amazed they are still used, let alone bought new! ■

DEAR SIR

WE HAVE INSTALLED TRUCKTIPPLER WITH LOAD CELLS AT ONE SPONGE IRON PLANT IN 1995 AND IS WORKING SATISFACTORYLY TILL DATE

THE SYSTEM WAS HAVING 2 TELESCOPIC HYDRAULIC CYLINDER WITH FLOW DEVIDER AND LOAD CELLS .COMPLETE SYSTEM WAS INSIDE STRUCTURAL SHED.

I FEEL IT IS BETTER TO PROVIDE LOAD CELLS BELOW PLATFORM ONLY SO THAT NET WEIGHT OF TRUCK CAN BE COMPUTED JUST AFTER UNLOADING OF TRUCK.

IN CASE YOU WANT TO PROVIDE WEIGH BRIGE TO WEIGH OTHER MATERIALS IN SAME PERMISES THAN COMBINED TRIPPLER WITH WEIGHER IS NOT NECESSARY

A R SINGH ■

Emsons thank you for your kind message to me this morning, and welcome to the bulk on line forum.

Please register with the forum so that we/I may

establish a line of cummunications if you wish or please use my email address, it is lzaharis@lightlink.com ■

Thank you Herr Wolbier for that information,

have you recieved any of the e-mails or private messages I have sent to you?

lzaharis ■

Thank you for your swift response,

I look forward to working with you

as I know I can offer many years of

valuable experience to the forum. ■

This has been done successfully in a few installations in North America. It is accurate enough if being used for material tracking; it may not retain it's accuracy sufficiently to meet `weights and measures' standards. Normally, weighscales are kept separate and they are very accurate if maintained properly.

The reason for combining them on a truck tipper platform is if a very high number of trucks are being processed and you want to minimize the truck's time required on site.

If you need further assistance, contact Mr. Peter Leekha at Sandwell Engineering in Mumbai, India, email: pleekha@sandwell.com.

Paul Janze

Sandwell Engineering

Vancouver, BC Canada ■

We are attempting to source a 60 mt hydraulic truck end dumper / unloader / tipper capable of pivoting so that the driver drives onto the dumper instead of backing on. Once on the platform it rotates and positions the truck for unloading by raising the platform using hydraulic cylinders. Is anyone familiar with this technique? Can you recommend a supplier? Thanks.

Don ■

Hello Don,

We have engineered the successful installation of several drive-over, end dumpers in various sizes and locations and there are a few qualified vendors. I would gladly recommend some suppliers if you would tell me:

- the region you are located in

- the material you are handling or the industry you are in

- the size and type of truck being emptied

A successful installation depends as much on good design and installation as it does on good equipment. Should you need any assistance ............!

Paul Janz

Sandwell Engineering Inc.

Atlanta, Vancouver, Montreal, Burlington, Mumbai

604-684-9311

www.sandwell.com ■

Thanks for your reply but there is no room to do a drive thru end dumper. It definitely needs to be a drive on / drive off but driving off in the same direction one came from. Sort of like when a the San Francisco cable car gets to the end of the line. It is spun around on it axis and it goes back the same way it came. I need a end dumper that can let me do the same. Surely this challenge has been met before. ■

In Goa many barge loading facilities have load-cell type weigh-bridge at the truck tipping location. The weight records are used for creating record for how much ore is handled by each truck (generation of truck log-sheets for payment to transport contractor.

The trucks are unloaded into barges. For material moved by a barge draft survey before loading and after loading is the only acceptable weight. Aggregate of truck weight record is only used as a cross-check. ■

Don,

Wow! A swivelling end truck dumper; that's a new one. I don't believe I've heard of that being done before. However, that's not to say that one could not be designed, but it would be a custom piece of equipment.

We often come up with new innovations; for instance a side-tipping dumper for Super B-Train trucks. This required a special 90' long side-dumper and special trailers. The dumper was the easy part. The key was to get a trailer that could open on the side, have sufficient strength and have the same carrying capacity as a standard Super B. We found a vendor who was willing to build both the side dumper and the special trailers and provide performance guarantees. The project was a great success.

So, if you were to give me a bit more information, I would put my thinking cap on and see what I could come up with.

- what size and type of truck are you using

- what is the material you are handling

- what region are you located in

Would you be the end-user or are you in engineering or a manufacturer?

Paul Janz

Sandwell Engineering Inc.

Atlanta, Vancouver, Montreal, Burlington, Mumbai

604-684-9311

www.sandwell.com ■

Paul;

The platform needs to be 8.5m long and 3 m wide.

The product to be unloader is sugarcane.

Maximum angle neded for total discharge is 45 degrees.

The total cycle time is 300 seconds.

We would be the customer (Houston, Texas) but the final destination would be Pakistan.

Regards,

Don ■

Don,

Thanks for the information. This dumper is quite small and I don't think that the technical problems of designing and building such a dumper would be insurmountable. In fact, from a technical perspective it sounds quite intriguing.

The problem I see is that I doubt there would be a market for such a dumper, and you will have trouble getting the interest of a competent dumper manufacturer willing to develop such an idea. This would be a one-off piece of equipment and I suspect you will have to pay for someone to custom design and fabricate it. And being custom built, it won't be low cost. Also, I doubt you will get the builder to provide any kind of a guarantee that you could afford.

On another note. I am all for technology transfer and helping one another out with technical problems. However, I like to know who I am dealing with. I don't know if you are an entrepreneur, an equipment supplier / integrator, a manufacturer or a competitor. You have not identified yourself, in spite of my hints. I checked your profile and you give no clues there either.

Therefore, I think this will be my last post on this topic.

Paul Janz

Sandwell Engineering Inc.

Atlanta, Vancouver, Montreal, Burlington, Mumbai

604-684-9311

www.sandwell.com ■

Paul;

You posts have been very helpful and informative. Thanks!

I failed to mention in my previous post that the quantity is four dumpers.

I am not sure what technology you think would need to be transfered. We are not expecting nor asking for your technology.

I didn't pick up any "hints" about my indentity but why hint around. Straight talk is what I like. Furthermore I thought I answered all your questions.

We are an equipment supplier / integrator but why should that matter to you? I intentionally have left off my employer's name and worldwide locations to keep the forum non-commercial but I will be happy to share that with you if that would be helpful. Just send me a private message.

Is Sandwell interested in receiving a RFQ for the four end dumpers we have been discussing? If so to whom should we send it to?

Best regards,

Don West ■