Please look at <www.Pnuetrans.net> and contact P. Brink Weaver via his web site -he also has a page where you can put all the relevent data relating to your project and he will give you a free quote for his system and you will save your self a lot of money,time and labor in addition to a system that carry both your coal and fly ash in return in addition to generating electricity by using synchronus motors.

To see a system in use daily in japan at a limestone quarry <www.capsu.org> the japanese built their system from the ground up replacing a railroad and utilising the old railroad right of way.

Your product volumes are well within the economical range for a capsule pipeline which to be economical require 100,000 tons per year at a minimum of product moved from point a to point b. ■

Dear sanjay

you intend to transport coal from mines to plant

incase coal size is more than 150 mm pipe conveyor is not recomended

rope way may be suitable in case capacity is less than 500 tph

why dont you consider Conventional belt conveyor

A R SINGH ■

I forgot to mention that the pnuetrans system,

creates very little noise or other pollution in my previous posting and it can be buried out of sight as well reducing tribal and village concerns. ■

Mr. Kumar,

If you wish a price comparison, request for a budgetary quote from designers of such systems.

CDI can offer a budgetary price for pipe and conventional belts as can FFE, Koch, Krupp and others with India representation.

Metso can offer the Cable Belt and your can obtain the name of the Ropeway supplier here for BSH.

Please advise on the issues of village concerns with conventional belts that are not a factor with pipe and ropeway.

As I have noted before in the forum, CDI designed a 7 km horizontally curved fully elevated overland conveyor. It is 5.5 m above the ground to minimize interference with animals, people, farm lands and roadways. Is this concept of interest?

As already stated by many, the conventional belt will be significantly lower in cost than the alternatives. Get the quotes and see. There are key design conditions that will allow you to make comparisons between the alternatives such as belt, idler, drive, structural costs and NPV operating costs. These I can provide and you can check to see why and where the differences are significant for these key components. You can also obtain the same from others. You will find the answer highly informative and necessary to argue for one system over another.

Send the particulars and I will respond on what added information is required free of charge. I have India representation that can help. ■

who mays send me tecnichal catalogue of pipe conveyors

thanks ■

Dear Mr.Sanjay,

I am sure our company will be provide a cost-effective solution to you in the form of pipe conveyors. Please forward your technical details along with contact details to my personal id raghavan1973@gmail.com. I am associated with an MNC operating in India and i will revert back to you with details.

regards,

Raghavan ■

This request is related to the question posted lately on how far we can go with pipe conveyors.

It is a clear concern that, at this time only 5km pipe conveyors have been built with an 8km unit in design. So to now suggest a 35km pipe conveyor is a little difficult to get passed the financiers and operators.

We have already done the analysis of this or a similar conveyor and because of the concern with the pipe belt design have tended to opt for the belt conveyor, however if we remove the rules and adopt a level playing field approach then the pipe conveyor could come into its own.

(Note I am deliberately ignoring a comment on the Cable Belt as passed postings confirm that it is not a real option).

Going back to the possibility of using a pipe conveyor for this application will relate to the routing, which translates into the number of transfer points especially when conveying in both directions.

Pipe conveyors can negotiate a more server route and to transfer a double carry strand system is very difficult therefore to eliminate transfer points will make the pipe conveyor a more suitable option.

However we can expect to draw more power with a pipe conveyor and although the pipe belt will be wider there is a real concern that the belt rating will be to high to allow the formation of the pipe.

Presently we are working with St 2600 and are investigating St 3150 at a width of 1650mm.

We test the belt carefully however we are all in the dark on how the belt formation will withstand the test of time.

However we are adopting the approach that using a good design team conducting all the possible tests and installing a very comprehensive condition monitoring system including belt deformation monitor, we will be able to extend the flight length in comparison to belt conveyors.

So to conclude, (considering the work we have done), we would state that on the basis of capital cost the belt conveyor will be at least 13% less than the pipe conveyor. The operating cost/ton km

of the pipe conveyor will be 7% less than a belt conveyor. ■

Dear Mr. Staples,

Did you do a typo error?

You claim the pipe conveyor will be 13% more expensive than the conventional belt. Then you claim the pipe will be 7% less costly to operate. Since this is counterintuitive, how do you do it?

Today, conventional conveyors can negotiate far greater curvature with far less power than even a few years ago. It will be far more cost competitive than the 13% savings claimed over the pipe.

Dear Mr. Kumar how did you determine that the conventional conveyor cannot offer the best solution? ■

Dear Mr. Kumar,

You state that the conveyor must travel near a village. I think you should explore the issue of noise. Make the provider of your system guaranty a minimum noise threshold that wll be acceptable to the local village.

I claim the pipe will close to double the noise of a conventional belt. The power increase is the key indicator of the difference in noise generated by the interface of the belt with the idlers.

Obtain an unbiased design power guaranty for the two systems from those that practice modern methods. ■

Read it again. Mr Staples claims 13% more investment & 7% less operating cost. It's like buying a good Japanese car against a run of the mill gas guzzler.

If noise is a problem, lag it! ■

Dear John,

I read it several times and am still puzzled. The pipe conveyor's greater expense is from its wider belt, greater number of idlers, and higher forming force (higher belt strength) to maintain its pipe configuration. These all equal higher power consumption as well as higher belt rating (total kN). So, where is the operating cost savings?

I don't care who answers as long as it is founded in accurate engineering.

I have more than a casual working knowledge of pipe conveyor engineering. For the benefit of all who seek knowledge from this forum, technocrats (me included) should not pontificate on possibilities unless they qualify that the claim is "opinion". If not an opinion, then the claim should be verifiable.

Is your claim verifiable Mr. Staples?

John, your noise reduction idea leaves something to be desired but not practical. ■

This thread has been with us for a while and we still do not have a lot of information Mr. Kumar.

Items such as the:

Hours of operation of the ropeway of pipe conveyor have not been addressed.

The desired size of belt conveyor or pipe conveyor.

Whether you expect to use the same unit for return of fly ash in the opposite direction on a bottom trough or an entirely different conveyor for fly ash return.

The terrain which it will encounter/be required to pass.

An average belt conveyor will require an idler every five feet and a support stand every ten feet plus training idlers every tenth idler for troughing and return.

An average belt conveyor will require a drive unit and transfer point every three thousand feet or less depending on terrain.

An aerial ropeway fitting your needs will require 2 inch seale wire rope @ 160 pounds per foot which amounts to 114829 feet of wire rope which amounts to 919 tons of wire rope for an aerial tramway of this length.

In order to meet your tonnage using gondolas you will need 303 one ton gondolas over the 35 kilometer distance 75 feet apart if and only if you expect to use every third gondola for fly ash on a continuos basis around the clock, you will probably have to put covers on them as well.

You have not even specified whether you will use a horizontal tram or a vertical tram to move the gondola cars through the towers or along the arms of the towers and at the unloading and loading points.

You will require a tower every 100 meters to carry the load of the ores/flyash and cables/gondola weight as well.

You have stated that you will move 13000 TPD of coal and 5000 TPD of fly ash, YOU HAVE NOT STATED

OPERATING HOURS DESIRED! let alone operating conditions terrain and weather encountered the year round.

The amount of time the fine members of this board have spent debating your questions with little input on your part leads me to believe that you have not done your home work as the information is readily available from many sources.

You seem to be trolling for answers and either intentionally pitting one board member against another with thier respective views regarding the methods of bulk material conveying.

PERHAPS YOU OR WE SHOULD ASK TO HAVE THIS THREAD REMOVED? ■

The detail I gave related to a study on a potential project and are based on factual information relating to the “True Operating Cost”, so what do I mean by this.

As system designers, we have been beaten about the head to get the project costs down by increasing belt speeds and reducing belt widths. Yes we all know how a reduction in belt mass can reduce capital cost, but we also know that a reduction in capital cost leads to an increase in operating costs.

Many projects become viable with the introduction of a low capital cost with both designers and operators HIDING the true cost of running the system in the long term, (we should not complain as it keeps us working I suppose).

However when one comes to the true cost of running a system the ITEMS that are hidden in the operating costs should be brought out into the open.

A straight belt conveyor against a straight pipe conveyor will be cheaper in capital and operating cost, No augment from any one, except if was to convey a material like Alumina where cleaning the belt is impossible, (I know someone will claim otherwise), then even a pipe conveyor will hold its own in operating costs.

So when introducing a transfer point into a system and comparing a single flight Pipe Conveyor with a horizontal curve and two belt conveyors, taking into account the cost of maintenance of the transfer point including, dust suppression, belt ware, chute and liner wear, spillage clean up, security, lighting, the additional pulleys, the list goes on and on.

Add all these items into your analysis and you too will arrive at the same conclusion as I have done so many times. A transfer point must be the final straw after all other options have been considered.

Yes I also know that there are magic designers out there who can eliminate all these issues but considering the number of conveyors in operation and the true costs of transfers, we as designers are negligent if we put in a transfer point just because! ■

Bang on right. It is a design duty to minimise transfers. tranfers are work we could do without most of the time.

Izaharis is clearly a ropeway guru though; pleasure to read. I think the thread will soon run its course. The guy wanted opinions & got 'em. ■

Bulk-Offline; that's an inspired username. Anything to do with the spillage you mentioned? ■

No, no & no. What self respecting pipe conveyor manufacturer would let you open up his pipe for fun? You are not transforming the troughed conveyor into a pipe for part of its run: you are transforming an expensive worthy pipe conveyor to a simple lowly belt conveyor for part of ITS run. It has to be one or t'other. ■

Dear All and Mr Nordel

Again really a pipe conveyor not more noisy than a conventional conveyor.

At the ends drive and tail it is very much the same but between the ends the pipe conveyor is quieter and we have done tests many times and there are technical reasons for this.

In some cases and our customer comments that they dont know the pipe conveyor is running it is so quiet, only when you see the belt moving or hear a faulty idler do you know it is running.

To say pipe conveyors are more noisy is simply not correct.

Paul Holt

Dosco Overseas Eng Ltd ■

The pipe conveyor should be quieter according to analogy to Melde's spheres & reflected noise & all that.

But; to paraphrase the famous Rolls Royce gripe "We must do something about that idler."

(For the young ones. The Chief Engineer at Rolls Royce was reading the road test of one of their cars wherein the journalist wrote that at 100mph the only sound was the ticking of the clock in the dashboard. Shaking his head sadly he muttered "We must do something about that clock.")

Paul, thanks for the insight into transition lengths in the other thread. ■

Dear Paul,

I believe you have measured pipe noise and found it to be satifactory as did your client. This is not a scientific test.

Take a benchmark belt with product and tonnage. Will you bet your life on it being of less noise than a equivalent 3-roll trough conveyor using the same idler and belt manufacturer.

The engineering data does not support it no matter how many times you say it does. This can easily be put to the test.

Take a conventional belt and reduce its load (capacity) until the belt can be wrapped into a pipe to carry the crossection for maybe ten idler stands. Here no significant change in belt tension will occur. Yet, we will see double the idlers a rollin. We will hear the added bending force of the belt being piped as it squirms to unravel its shape. Then do the measurement on each set. Whadya wana bet? I got the conveyor. ■

Dear Mr Nordel

Yes I would, and there is some technical engineering aspects to support this.

One of the reasons that the pipe conveyor is quiet along its length is that when it is in its pipe form the tube is inherently stiff with very little deflection or sag so when it reaches an idler set the belt glides through rather than hurdling the idler, this also gives less local compression of the belt giving good life.

Also the idler spacing for the tube is greater than for conventional belts.

However the most important to us is that our customers tell us the pipe system is very quiet and generally quieter than similar conventional system.

Paul Holt

Dosco Overseas Engineering Ltd. ■

Dear Paul,

I grant you that the surrounding pipe mutes ore agitation. Ore agitation is typically a small contributor to noise.

We have measured conventional and pipe conveyors for noise. The squirm and echo of the belt to idler are the largest contributors. By our measurements, there is a 15% increase in the apparent noise.

When you state the pipe conveyor has a larger spacing, please quote a source of your claim. I think much is hyperbole. I have not seen or heard of any pipe conveyor that is equipped with a reputed "long" idler spacing.

Can you expalin further on the theory of "less compression"?

Since you said you are a betting man, what do you wager? I will endeavor to make the test where a conventional belt is wrapped into a pipe. The loser pays all expenses and salaries to make the test. Tell me the rules. Maybe we can do it in Australia. ■

From a lofty pedestal of Unit Responsibility for an 8MW propylene refrigeration plant, where one of my major concerns is the interaction between lighting, HVAC & flammable gas detection equipment in the acoustic enclosures, can I carefully suggest that quantitative evidence is presented or the arguments withdrawn. If I dared to suggest that my compressor vendors wagered on the outcome of arbitrary performance criteria.. I would have no vendors. There are quite straightforward acoustic criteria adhered to in other industries. In a lot of places they are legally binding. (Did I mention lagging earlier?)

Rules for the contest can be found in any good noise measurement instrumentation manual & the results of the (con?)test can be posted to Australia or anywhere else for that matter.

Regarding the issue of contact pressure; it is bound to be greater with a tube, on the lower rollers anyway, but hopefully this is countered by the absence of the annoying nip business in the corners of troughed belts.

If I ever bought a conveyor again I would be more interested in the relative stiffnesses of the tube & troughed configurations through horizontal curves. Tubes seem to win hands down & for vertical curves it is again a case of no contest.

A spreadsheet, metre by metre, comparison of tubes & troughs could be plotted for typical routes. I suspect they would indicate that the overland troughed belt has neared its sell by date. ■

Dear John & Paul,

A bit of background that I have written of in past responses:

1. CDI developed a full 3-D FEA model of all stress and pressure factors of a multi-variable, multi-composite pipe conveyor for Bridgestone. The development took one year. Many validations were completed at all phases of the development. The model took too long to make a typical analysis and was shelved as a commercial tool.

2. Then developed a second model based on fewer differential equations of belt construction and shape forming and reaction forces. This took about 3 months to install into BELTSTAT with our already developed polymer rheology power model. It can solve the interface pressures in a matter of minutes for a typical 3-5 km pipe overland with up to seven layers of rubber, fabric, and steel. All forming forces, vertical and horizontal curve forces are incorporated.

3. Analyzed 10 Bridgestone installation, that they had historical data on, for power and resulting belt tensions

4. Field strain gauge measured the pipe conveyor at Roberts Point in Hawaii for drive torque and various tension behaviors along with sound pressure readings that were above 100 dba at 1 meter.

5. Part of design team for Birla Copper, India along with Babcock, RSA and Naveen Ltd, India. Unfortunately, CDI did not commission this conveyor as it conflicted with another commissioning that could not be postponed. It was in our contract, and our then partner, Mr. P. Staples did accept the responsibility to commission the system.

6. Performed repeated field measurements of many overland using hand held dba reading over 1 meter to 100 meters and the resulting attenuating curves such as: a) 4 km Warkworth overland in Australia with belt speeds to 6.5 m/s and idler spacing at 4m on the carry and 8 m on the return, b) BHP Billiton CRUII 14 km overland in South Africa with 5 m/s and 4.5 m idler spacing on the carry side and 9 m on the return. We try to make a practice on recording results of various projects to check construction details against performance.

7. Witnessed Bridgestone testing of pipe belt construction forming forces in their lab in Yokohama.

The Rules I suggest be submitted include controls of testing, measurement equipment, where measurements are taken, recording wind direction, speed and temperature, taking care about hood covers, since the covers would need to be removed to form the pipe, et al. Certainly witnesses are required. ■

Dear Sirs

If I can clarify some points.

Regarding compression I an talking about the squeezing or compressing of the belt when it approaches the idler when a convetional belt is loaded this is greater due to the sag. With a pipe conveyor there is little sag due to the inherant rigidity of the tube. In the case of a diameter 400mm pipe the spacing would be 2 meters a convetional belt of 1600mm would be less. With a pipe conveyor there is little difference between loaded and unloaded again because of the tube rigigidity. Bridgestone have done many tests on this.

We have installed a diameter 400mm at a UK power station and noise was 71 dbA 1m from the conveyor and 60 dbA 2m from the conveyor.

In several of our installations the customer comments that it is very quiet, and less than other systems.

I believe it does depend on good alignment and good and none touching idlers and correctly specified belt.

However I do concede that if you dont have this and with the number of idlers you could have a noisy system.

Paul Holt

Dosco Overseas Eng Ltd ■

Dear Paul,

Please tell us the idler diameter, belt speed, width, and tonnage.

Typical conveyors have a noise index of 70-78 dba at one meter traveling at a speed of 4-6m/s respectively with 152 mm diameter rolls.

The noise level cannot decay from 71 to 60 dba in one meter unless you are passing through a bulkhead. The integration of adjacent rolls, top, bottom and sideways, add to the local noise as does wind. I have not looked up the formula for noise attenuation, but intuitively your 71 dba at one meter cannot drop to 60 in one additional meter, but maybe 65. ■

Dear Mr Nordel

Yes on this conveyor it was a diameter 400mm 1600mm belt width at 3.35m/s although rated at 1200 T/hr it normally runs at 800 T/hr although as I said with and without material is very little difference. The panel spacing is 2m and idler diameter 127mm (Rulmeca). The conveyor has top cover and mesh side guards.

With our other test site mining work we are experienced at taking noise readings, but the reason we specifically took them in this case was that we and the customer were surprised how quiet the system was, this was 13 years ago, I have been with pipe conveyors for 20 years and in the early projects we did have some systems which were more noisy due to poor tolerance and quality control on the idlers, but in recent years they have been much better giving a significant reduction in noise.

Paul Holt

Dosco Overseas Eng Ltd ■

Paul,

I assume the Rulmeca are plastic rolls. This can lower the noise by 25%. Also note the sound pressure is a logarithmic scale

I do believe that the normal troughed belt will be in the low 60's dba if we apply the plastic roll, reduced speed to 3.35 m/s with a 1050 wide belt, ore agitation and all.

Note, your specifications for the pipe are extreme. In order for it to work at all, it has a loading of 79.2% at a bulk density of 1000kg/cm. Most coal placed in pipes are designed at 850 kg/cm. It cannot transport a product with particle size greater than 50 mm dia. The belt overlap is 343 mm.

This is not a typical pipe conveyor design. I would expect the noisier following design:

1. belt width ............... 1500 mm vs. 1050 mm trough

2. speed ..................... 4.2 m/s 4.2/3.35= 25% higher speed

3. idler speed ............... 528 rpm 528 vs. 427 rpm

4. x-sectional loading ... 71. %

5. belt overlap ............. 212 mm

All of this is conjecture. I continue to elaborate hoping you can see the philosophical design will favor the trough belt. ■

An epiphany:

I have seen specifications for conventional conveyor designs with speeds over 4 m/s which had a guaranteed noise specification of 55 dba do to the conveyor proximity to dwellings. This could only be achieved with plastic , polymer coating or aluminum rolls.

Test specimens were lab analyzed before the rolls were installed.

I must assume the speicifcation was met. I believe Prok and others quoted the project. ■

Mr Nordell

No the idlers were normal commercially available steel ones.

The pipe conveyor diameter 400mm (belt width 1600mm) at 3.35 m/s.

Handling conditioned ash at 1 T/m3.

Length 1100m lift 9m with 450 kW installed.

At 800 t/hr pipe is 46% full at this fill we would accept lump size of 240mm

At 1200 t/hr pipe is 68% full without problem, At this fill rate we would accept lump size of 133mm.

Paul Holt

Dosco Overseas Eng Ltd. ■

Paul:

Help me. How did you arrive at 68% loading?

Based on your numbers, and what I used to claim a 79.2% loading are as follows:

Needed Area = (1200 t/h)(h/3600sec)(cm/1t)(s/3.35m) = .099502

Available Area = (pi)(diameter)^2/4 = (3.14159)(.4^2)/4 = .12566

Percent filled=Needed/Available(100) =.0995/.12566(100)= 79.2%

Place a 133 lump on this needed area and you push the lump through the roof. At 15 deg. surcharge, the lump protrudes through the pipe diameter by about 60 mm.

I will say no more. ■

Mr Nordell

Here is the reason.

Pipe dias are nominal 300, 350, 400 etc.

For a diameter 400mm

Actual pipe bore dia is 428.6mm, Belt width 1600mm, belt thickness 14mm, Pipe core dia 442.6mm, belt overlap is 54 deg or 210mm, inner length between idlers 456.6 Available CSA = 0.1443 m2

At 1200 t/hr or 1200 m3/hr and 3.35 m/s material CSA = .0995 m2

68.9% fill.

Paul Holt

Dosco Overseas Eng Ltd ■

Mr Nordell

Sorry further regarding lump size. It depends how many lumps are at the max size but generally for diameter 400mm at 75% fill we accept a max lump size of 133mm or at 50% fill a max lump of 240mm. This does not cause a problem but of coarse it is better to be on the conservative side.

Paul Holt

Dosco Overseas Eng Ltd. ■

You should be looking at a third alternative.

You will be pulverising the coal for using in the boilers. You can consider pulverising the coal at mine site and consider slurry transport of coal fines to power plant.

Pipe-line will run buried in ground or can be laid like any other oil or natural gas line. Pipe-line act will enable you to get right of way. 35 km is a small distance for a slurry pipe line.

A second pipe laid alongside can transport fly ash in slurry form to mines for back filing.

Vinayak Sathe ■

The energy loss from latent heat conversion will cost far more than any differential cost saving between slurry and belt conveyor transport.

Drying of the ash is no easy task. Whereas fly ash has significant benefits as a binder in cement, fillers in many compounds such as plastics, polymers, et al.

The power plant industry should study better ways of precipitating the ash gas to control the shape, size, and other beneficial properties that increase flyash particle value. ■

Dear Sirs

Further on pipe conveyor and noise for additional information.

I have just returned from our latest installation at UK power station.

Conveyor diameter =300mm idler diameter = 89mm speed =170m/min installed power 110kw.

I have today measured Noise 1m from conveyor 68 dbA and also it was 68 dbA 2m from conveyor. So in this case background noise has greater influence.

Paul Holt

Dosco Overseas Eng Ltd. ■