Conventional Conveyor Versus Cable Belt
I'll make some loose comments which I hope will be helpfull. Hopefully others will contribute more substance.
The Cable Belt system separates the material carrying function from the tension and power function. The belt merely carries the material and is itself carried on parallel steel wire rope cables. All power and tension is transmitted through the cables. This should result in substantial reduction of belting costs and the cables have a very favorable unit cost for the strength provided. The cables are carried on Sheaves (wire rope pullies) of relatively large diameter (approx 280 mm typ.) and these sheaves are spaced far apart, along the length (6 to 12 meter centers). This results in very low travel resistance because of the large D/d ratio and the near elimination of the indentation resistance. Furthermore the material is cradled and not as agitated, thus substantially less energy required. This energy savings is especially significant where useful work (net lift) is minimal.
In actuality the belting is not so cheap because transverse strength, required to carry the material between the cables, is realized by special transverse straps (imbeded steel or fiber glass bars) or cross rigidizing wires. This cross-rigidizing will be significant for your proposed load of 4000 t/h. Full length parallel moulded grooves, two each at carrying and underside of the belt, position the belt onto the steel cables.
High wear, thus maintenance costs, has been experienced at the wire rope and carrying sheaves. Originally the wire ropes were subject to unacceptable wear. This was mitigated by lagging the sheaves with polyurethane. This resulted in high wear of the polyurethane lagging. Design of the sheaves was modularised to allow decoupling of the rim (called the polyrim) so it could be easily replaced or relagged. This has been a very costly problem. I have heard that advances have been made in this area by coating of the cables. I laso heard of advances using kevlar cables. There hasn't been much literature of late on the Cable belt system.
There is so much more to the Cable Belt system, and its comparison with conventional conveyors, than I can cover here.
Especially relavent to your requirements however is the story of the Selby project in the UK. At Selby parallel systems were installed, a cable belt system and a steel cord belt system. This was a proving ground where the two systems could be compared. The lifts were very significant possibly exceeding your requirements and the systems were longer than yours. The design rate was not as high. There were many articles written initially on this project and some after operation began. I hope that other forum participants will cite these articles.
I know this isn't much but I hope it is helpfull.
Joseph A. Dos Santos, PE ■
Cable Belt - Worsley
Worsley Alumina Pty Ltd in Western Australia
with a total length of 51km. Built in 1982/3 the cable belt is the lifeline of the mine.
OEM was called CABLE BELT UK. It holds the world record for the longest flight conveyor 31km centre to centre operating at 7.6m/sec @ a capacity of 2 750t/hr. Head end drives 2x3300kW and tail end 2 x 1700kW. They are reviewing the option to increase the tonnage to 3250t/hr - 14m/t/a.
The complete conveyor is made locally including the belt
Zip file containing 4 pictures of cable belt is attached.
A disadvantage of system is the huge drive stations required compared to the conventional conveyor drive stations.
Conventional conveyors with low friction idlers & low indentation
parameters is proven low maintenance & low risk technology.
In addition there are several holdback technologies available to prevent reverse belt run & cope with adverse conditions such as belt snap.
Regards
Hans Granig
Attachments
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Re: Conventional Conveyor Versus Cable Belt
Hello Mr Rosenthal,
I worked on the Selby Project and am able to comment on both the systems mentioned. Our contract was to receive, stockpile etc. r-o-m from the 2 drifts. Both the Cable Belt & the Stell Cord Belt were top of the range. Feelings on site were that the Cable Belt was installed because it was, at that time, a subsidiary of the National Coal Board.
All operating considerations apart, the complexity & size of the machinery inside the Cable Belt drive station buiding had to be seen to be believed. I compared the drive layout to a fairground where the Safety Officer had gone completely mad. Huge sheaves set horizontal and hauling great thick cables were just waiting to nip operating staff in half. Totally dangerous and wonderfully Victorian in its complexity.
In the other building the REI/Anderson Strathclyde SC belt was quite simple and ran very smoothly due to the high quality of the installation.
Site visit: If you are very quick you could see the installations mentioned by other correspondents at Gacoigne Wood (Selby , North Yorkshire). The mine is scheduled for closure sometime soon.
Literature: Very little literature willl be available. As far as I remember Cable Belt finally got involved with with BRECO (British Ropes Engineering Company) who supply excellent aerial ropeways. I have always found them very helpful in all technical matters.
History: Original Cable Belts were made by a Scottish Miner who was tired of underground belt breakages. His solution was to reinforce the belt with cables along each edge and use conventional splicing clips to secure the ropes to the belt edges which he then supported on rope sheaves. Then he found he could dispense with the idlers and somebody saw the potential cost savings. Cable Belt came into existence and developed alongside similarly novel, at the time, Steel Cord belts. Not every good idea can be a roaring success (just ask me!!) and some of them have to be confined to history.
Design Criterion: As mentioned elsewhere in this thread the weft stiffness of the Cable Belt is a contentious cost issue. It also limits the carrying cross sectional area. Geometrically speaking the Cable Belt must whistle along faster to compensate for the fact that it is essentially a flat belt. If we accept a direct relationship between wear and speed then it loses anyway, whether there is additional complex machinery involved or not. Then ask yourself; how far would you go as a conveyor designer in this penny pinching world if you only proposed flat belts? ■
John Gateley johngateley@hotmail.com www.the-credible-bulk.com
Conventional Conveyor Versus Cable Belt/Hauled Conveyor
The Cable Hauled conveyor system is an ideal conveyor system for use in applications where you have a long lenght (+5km.), High lift or large capacity (+1500mtph). Once you have 2 of these parameters, the use of a Cable Hauled conveyor system is both technically and financially acceptable to the end user.
Your project/study would be an ideal Cable Hauled conveyor system application.
If you would supply me with your e-mail address, I will reply to you with the requested information you have asked for, on this type of conveyor system.
Regards,
Keith Milford
JLV Industries Pty Ltd.
South Africa ■
Re: Conventional Conveyor Versus Cable Belt
History :
Cable Belt Ltd. was formed in 1949. Cable Belt conveyor systems were frequently chosen by the National Coal Board and a total of 86 Cable Belt systems were installed at NCB mines. However, Cable Belt Ltd. was never a subsidiary of the NCB. Cable Belt Ltd. was purchased by the Laird Group who after many years of ownership sold it’s Cable Belt interests to Svedala in 1997 and in 2001 Svedala became part of Metso.
Operating Costs :
Traditionally the long term operating costs for Cable Belt systems have been lower than comparable Troughed Idler systems. Reference to this advantage was made in the 1998 SME short course entitled “ Moving Bulk Materials : Technical and Economic Considerations in the Design of Belt Conveyors” prepared Walter Kung (Materials Manager, Flour Daniel Inc) and Steve Casper (Consulting Engineer). With backing from Svedala and Metso, substantial effort has been committed to develop the Cable Belt system to further reduce operating costs and simplify maintenance. The Metso MRC Cable Belt system represents the latest generation of equipment, whilst it maintains the fundamental advantages that are inherent to the Cable Belt principle it includes a number of significant improvements that should yield significantly lower long term operating costs.
Material Disturbance :
A traditional Cable Belt advantage leading to low power consumption, minimal wear of the belt, minimal material degradation and very little flattening of the material surcharge angle. On Troughed Idler conveyors there is much agitation of the material as it rises and falls when passing over each idler and as the belts troughing angle opens up after passing each idler set. On Cable Belt conveyors the belting is continuously supported by the cables, the amount of troughing remains constant throughout giving the material a very smooth ride.
Indention losses.
A traditional Cable Belt advantage leading to low power consumption and was well described by Mr. Santos.
Belting Costs :
A quoted conveyor system price should include the cost of belting and estimates for long term operating costs should include the cost of replacement belting. Typically only the life expectancy for normal wear is considered, but accidental damage can add to the long term cost. A steel bar accidentally loaded with the material could puncture the belt and become jammed against supporting structure and this could lead to destruction of long lengths of belt. This is typically a problem for Troughed Idler conveyors, but not for the Cable Belt where the belt’s tensile characteristics ensure that it will break if it becomes jammed. The break can be repaired within a few hours using mechanical fasteners with very little loss of belt or down time. I believe 3-4 km of belting on the Selby, Troughed Idler conveyor was destroyed by this sort of accident. The amount of spare belting available on site should reflect the risk of damaging and be included in the capital and operating cost estimates.
Drive Cable / Pulley Wear:
Troughed idler replacement and refurbishment of cable support pulleys are the primary routine maintenance tasks on the two systems. Many of the Cable Belt developments have been focused on reducing the support pulley maintenance. The TRITON cable was introduced by Cable Belt in 1991 to reduce pulley wear. Each individual strand had it’s own plastic cover. The plastic covers separated the individual steel strands to prevent inter strand friction and the outer part of the strand covers were shaped to produce a completely cylindrical outer cable surface that was a lot kinder to the pulleys. However, the outer cover of the TRITON cable was susceptible to damage and wear and the ZEBRA cable has been introduced to improve this feature. Compared to a standard steel cable, laboratory tests have shown that an improvement in the cable’s fatigue life of x12 is possible and operators are experiencing improvements in pulley life that are in excess of x2 after changing to ZEBRA cables. The steel strands are separated by hour glass shaped plastic inserts that prevent inter-strand friction and generate a smooth outer surface for good pulley wear. Part of the steel strand is still exposed and this makes the ZEBRA cable a lot less susceptible to wear /damage. Pulley wear is also significantly improved by good alignment and recent developments have been focused on making alignment easier to achieve and maintain.
Other Maintenance Items :
Long term costs of belt replacement and drive cable replacement should be considered. Components that transmit the drive will be subject to wear over extended periods and should also be considered. The Cable Belt friction drive wheels, which transmit the power to the drive cables, are fitted with replaceable linings, but the wheels them selves seldom require replacement. On Troughed Idler conveyors the driving drums may have a replaceable lining but the drums too may have a finite life. Cable Belt “cable deflection sheaves” and the Troughed Idler “belt deflection drums”, will be subject to wear. On older Cable Belt systems the deflection sheaves were hardened steel and required removal for re-machining and re-hardening when worn, but replaceable linings are now offered and these can be changed without removing the sheaves. I think that most operators would agree that transfer points require a significant amount of maintenance and are potentially a source of down time and belt damage. Loading frame seal plates and belt cleaner blades are typical wear items. The life of all components will be a function of design considerations and operating conditions and should be evaluated for the specific application. Power consumption is usually a significant cost consideration as will be the labor requirement to carry out operation and maintenance tasks.
Belt Capacity is a function of the material cross section, belt speed and material density. Unit loading is derived from material cross section and density. For Cable Belt conveyors the unit load requirement relative to the spacing of the drive cable supports determines how much cross stiffness is required and this can easily be adjusted at the design stage by making changes to the belts core thickness or stiffening elements. Cable Belt belting is designed to trough under load and in 1988 Cable Belt introduced the PVL belt, which included a 6 degree empty pre trough to increase the total loaded troughing angle from 9 to 12 degrees. Since then Cable Belt has also developed a belt with a 12 degree pre trough. The belt is positively located on the steel cables by molded projections and this effectively eliminates the possibility for belt wander. Belting used on Troughed Idler conveyors does not include this positive location and it’s potential capacity is reduced by the need for a substantial edge distance to compensate for the wander. Also the minimal material disturbance that occurs on a Cable Belt system allows steeper surcharge angles to be achieved and this increases the belt’s volumetric capacity. After considering the above the capacity of Cable Belt and Troughed Idler belts are quite similar. However, if a curved conveyor route is required the Troughed Idler systems generally negotiate the curves by tilting the belt and this substantially reduces their volumetric capacity, but with a Cable Belt system the belt remains effectively flat and suffers very little loss in capacity. Current Cable Belt installations negotiate routes with curve radii as small as 400m in this way. The Cable Belt system is very well suited to higher speeds and it is often possible to carry the same load with a significantly narrower belt. I have attached some photographs to demonstrate the carrying capacity of the Cable Belt system for various materials.
Drive Unit Size :
The older designs could be very large but in 1991 Cable Belt adopted a totally new style of drive unit that used separate reducers fitted with hardened and ground gears and a custom low speed differential. This drive unit was much smaller than the original design and separating the reducer and differential functions made it easier to maintain. Also smaller intermediate booster drives may now be used instead of one big one and this allows much smaller cable diameters and deflection sheaves can be used. Intermediate tripper drives are also used on modern Troughed Idler conveyors, but these require that a belt loop be incorporated and this introduces a material transfer point. An intermediate drive can be introduced on the Cable Belt system with out disturbing the material as it is possible to locally withdraw the drive cables from the belt line to insert a booster drive.
Conveyor Length :
Cable Belt has a history of leading the way with respect to long distance conveyor applications. Numerous distance records have been broken and the two conveyors supplied by Cable Belt to Worsley Alumina
are still the #1and #2 longest conveyors in the world (30.4km and 20.7 km). Cable Belt also sold a 14.5 km conveyor to Peabody coal in Kentucky in 1969 and at that time it was the longest conveyor in the world (it is still running today). In 1984 Cable Belt sold the longest curved conveyor in the world (18.1 km) to Dead Sea Works in Israel (also still running today) and there are other record breakers.
I trust that this has helped clarify the status of the modern MRC Cable Belt system that can be supplied by Metso. I am having difficulty attaching photos, but I will try again later. Let me know if you need help arranging site visits.
Alan ■
Cabel Belt Vs Conventional Trough Belt
Dear Sr. Rosenthal,
We meet again.
Conveyor Dynamics, Inc. has unique experience and understanding of the Cable Belt concept obtained from court council for Cable Belt's defense in two court cases:
1. Cable Belt vs UK operator about to shutdown
2. Cable Belt vs Canada
CDI argued for the defense. We had to become informed of the special design, construction, and operating conditions. Site visits and a litany of court documents give us special perspective and the does and don'ts.
There are serious design issues which I cannot elaborate in this forum.
A number of the earlier comments made by forum participants are not correct. I suggest two public domain articles:
1. Worsley Aluminum 1983 (designed by Kaiser Engineers) in Australia - It cost the client another 40 million to get the conveyor into operation after they spent 60 milion to purchase. Many design flaws were discovered and to this day have not been corrected. The operating cost is extreme. Every day repairs need to be made.
2. Selby UK, Mr. Ian Dixon published a gentle but scathing article on the cost to operate. It is many fold the cost to operate the standard trough belt. It also has a speed limit of 6.5 m/s as did Worsley.
I can say more in private if you wish.
Lawrence Nordell
Conveyor Dynamics, Inc. ■
Re: Conventional Conveyor Versus Cable Belt
Cable Belt vs Conventional Trough Belt
In response to Mr. Allen George, who is an advocate for Cable Belt, I ask him to back up these suspect claims:
1. Lower rolling resistance:
Mr. George please document the new generation of low rolling resistance measured on Cable Belt. I claim it is not as you claim, as experience has shown, and as the physics demonstrates. The cables puts a much higher localized pressure on the polymer inserts thereby increasing the polymer hysteresis which equates to higher power loss and which also leads to their greater wear. Todays conventional trough belts have a net rolling loss, per DIN 22101
f < 0.0085 as has been published about the Channar 20 km overland.
I do not think Mr. Barfoot and Kung are to be given due respect, because of their involvement with Fluor and Fluor's recommendation for the Line Creek Cable Belt. I do respect them as capable engineers. I do not think they have thought this problem through or know of the present status of Line Creek and its missgivings.
Mr. De Santos is incorrect in his assumption of the low rolling resistance assessment. There is a polymer (insert or cable poly covering) interaction with steel. The poly rim is a high hysteresis loss compound (ie. plastic) and the steel cable (aka idler roll) produces a higher pressure and has, in addition, a sliding loss component not commented on by the senseis. The idler sheave cheeks have a differential speed that produces a sliding action that is a principle cause of their wear.
2. Wear and Replacement Rate of Poly Rims or their latest adaptation:
I request you document the New Generation of Poly Rim to demonstrate the improvement with associated references. There is an inherent flaw in the past designs that caused the excessive wear. The sheave design continues to be a work in progress. I am not aware of significant improvements. Look at Line Creek for among the latest poor performance indices.
I believe wear may also be linked to heat generation. The plastic's hysteresis, causes significant heat that cannot be easily disipated. Even on large pulley lagging, heat build up is measurable and agrees with the theory on the same. We measured the heat buildup on Palabora during normal running. If my memory serves me correctly there is a 35C buildup on the 4700 kW head drive lagging. This is a 2m diameter drive pulley and has about 88 cables, in the ST-6600 N/mm belt, each at 12.4 mm diameter with 34mm of rubber foundation. Compare it to the poly rim pressure and potential for heat buildup. The polymer will begin to degrade as the temperature exceeds 65C when under high stress.
3. Lower Operating Costs:
Give the community a documented cost breakdown that can be reasonably assessed. I bet it will not happen in any public forum.
The only public published accounting for the operating costs came from Mr. Ian Dixon, the operating engineer for Selby. He compared the Cable Belts against the REI/Anderson Strathclyde. The Cable Belt came in a very poor second.
4. Wear & Tear:
Visit Selby an other installations. Look at the pile of galvaninzing being stripped of the tension calbes that lays about the hugh bend sheaves. Feel the floor vibrations and observe the cable resonance. Look at the replacement record of cables. A conventional overland, designed today. will last +20 years without replacement.
5. Summary
Maintenance cost and dedicated personnel are greater with the cable belt.
Power is not reduced.
The cable belt uses a lower safety fact = 4:1 vs conventional belts using 5.5:1. Is this an advantage or higher risk?
Conventional belts have been designed down below 4:1. These levels should not be tried without full knowledge of how to do it. The expertise of conventional designs is tested on adaily basis by many enginners and academics around the world. Cable Belt is tested by few, in secrecy, and with biases. Can you get an impartial judgement on it effacy?
Lawrence Nordell
Conveyor Dynamics, Inc.
www.conveyor-dynamics.com ■
Conv.conveyor Versus Cable Belt
Dear Sr Rosenthal,
We have been working with the Cable Belt Conveyor
since 1987.
Our Conveyor: 18 km length, 800 m lift, up to
800 tph, 4000 kW.
Material - bulk potash, four grades.
On the initial stage of the project we met the same
problem as you are now.
We carried out the profound comparison between
the Cable Belt Conveyor and the REI/Andersen
Strathclyde Steel Cord belt Conveyor.
We had chosen the Cable Belt Conveyor.
Our arguments:
1. The energy consumption is slightly lower for the
Cable belt Conveyor ( see para 5 ).
2. Practically the same drive unit for two cases.
So, if it is a "huge" drive station, it is in two
cases.
3 The same material surcharge angle for two
conveyors.If somebody tells you that the
angles are different, do not believe.
Cable Belt pre-trough belting eliminates
spillage.
4. About 15 % of poly-pulleys should be replaced
during one year.
5. Safety factors for cables:
our Cable Belt Conveyor 3:1 ( no problems!),
REI/A.S. 5:1 ( the NCB requirement ).
6. The advantage of the Cable Belt principle:
the belting does not run away from the
cables.
The belt adjustment is not required!
7. The service life for the Cable Belt:
cables 5-6 years ( very corrosive environment
in our case ),
belting : up to 15 years.
8. Summary: good luck!
Michael Rivkin
7
4, ■
Re: Conventional Conveyor Versus Cable Belt
Advocate for fair analysis:
Sr. Rosenthal,
To provide counterpoint to Mr. Rivkin's 18 km with 800m lift, and 800 t/h of potash to claim virtues of the conventional conveyor, I offer the following conventiional conveyor specifications that would be built today for comparisons:
1. Belt width = 900 mm
2. Belt speed = 4 m/s
3. Belt Strength = ST-5000 N/mm @ SF = 4.8:1 @ 10 deg C.
4. Power Required = 3000kW nameplate @ 2800 kW demand
Thus, power demand is less for modern standard trough belts than for the Cable Belt system.
I feel qualified to set these specifications having experience in association with Krupp, Canada in Chile and for other long distance systems:
1. Collahuasi, in design, transporting up to 10,300 t/h, with horiz curve, 8.2 km long, rise =266 m and drop =383 m, speed =6m/s, 16,400 kW, ST-6300 N/mm
2. Los Pelambres, commissioned 2000, transporting up to 8700 t/h, 12 km long x 1300 m drop, 8700 t/h, speed = 6m/s 25000 kW, ST-7800 N/mm
3. ZISCO, Zimbabwe @ 16 km long, 1995-1996 w/ horiz curve
4. Indo Cement, Indonesia @ 24 km long, 1998
5. Muja/Collie, Australia @ 14 km long 1998 w/ horiz. curves
6. BHP Billiton, RSA Ingwe CRU-II, 14 km long 2000 w/ horiz curve
7. Channar, Australia 20 km long 1989 w/ horiz curve
Idler repair 1-2 % per year
Belt replacement + 14 year to +20 years
Horizintal curve technology is well proven and maintenance free.
No tracking problems or belt adjustments(??)
Lawrence Nordell
Conveyor Dynamics, Inc.
www.conveyor-dynamics.com ■
Conventional Conveyor Vs Cable Belt
Mr Nordell,
Speaking about your alternative proposal for the
potash conveyor, would you advise
the weight of the belt (empty) per meter ?
Thank you,
Michael Rivkin ■
Re: Conventional Conveyor Versus Cable Belt
Yes Michael,
The belt mass I used was 41 kg/m.
What is the low temperature design criteria?
I assume you are doing a calculation. I am interested in your comments and anticipate you will have more questions.
Regards,
Lawrence Nordell
Conveyor Dynamics, Inc. ■
Re: Conventional Conveyor Versus Cable Belt
As I know, one Aluminum company (NALCO) in eastern part of India has a long cable belt conveyor, installed possibly two decades ago. As I know, possibly it has not worked satisfactorily. Hence, this equipment has not become popular in India. Interested parties may check and find out the facts.
Regards,
Ishwar G Mulani.
Author of Book : Engineering Science and Application Design for Belt Conveyors.
Email : parimul@pn2.vsnl.net.in ■
Re: Conventional Conveyor Versus Cable Belt
Sr. Rosenthal:
A possible benchmark solution, using a conventional conveyor, might have the following specifications:
1. capacity = 4000 t/h
2. belt width = 1200 mm
3. strength = ST-6500 N/mm @ SF = 5:1
4. speed = 7.5 m/s
5. motor power = 10500 kW (nameplate)
All of these specifications are in the working spectrum.
There are better / more economical solutions which ca be explored once you feel the interest is strong enough.
Lawrence Nordell
Conveyor Dynamics, Inc. ■
Conventional Conveyor Vs Cable Belt
Mr Nordell,
1.The weight of our belt is 21 kgf/m, plus weight of
2 ropes ( 52 mm dia) x 10 kgf/m and we have
got the same 41 kgf/m.
2.We have the same lift power consumption
(qm x H).
3. Each our linestand supports 4 polypulleys or
8 bearings - on the carrying run and the
distance between polypulleys is 7 m.
4. Max measured power consumption for our
conveyor is about 3200 kW, the same result
you can get from your calculation, if you put
a real ( no theoretical) line bearing friction
coefficient.
5. I don't think that the power consumption is
the key factor to choose the type of Overland
Conveyor.
The key factors:
- reliability of the equipment,
- operating costs.
Michael Rivkin. ■
Re: Conventional Conveyor Versus Cable Belt
Michael,
I agree that power, by it self, should not be the sole criteria for judging a design concept. However, you did make it a point of adjudication.
To belabor the point of conventional (2800kW) verses Cable Belt (3200kW) yields the following cost difference in 15 years NPV:
400 kW difference = $2.3 million dollars in Net Present Value at:
$0.10 /kw-hr., 6000 hours /year, 6% money over 15 years is a 9.71 multiplier
I did use a realistic bearing and seal friction from test work of used idlers.
You note key factors are:
a) equipment reliabilility
b) operating costs
A. Equipment Reliability:
I referenced the report of a client who published actual performance figures. You furthered the issue by noting the idlers need a 15% poly-rim inspection and replacement rate per year, verses 1-1.5% per year for conventional trough idler rolls.
You also note the 6-7 year rope life replacement cycle. A well designed 18 km conventional troughed overland conveyor should not need a belt replacement for +20 years which includes the steel ropes.
B. Operating Costs exclusive of operating crew:
These consist of;
a) power
b) maintenance crew required on daily or weekly
c) belt replacement due to wear or rubber degradation
d) idler replacement - bearing failure, roll shell or poly-rim wear
e) chute and skirt liners - metal and ruber consumables
f) instrumentation failure and replacement
g) pulley lagging
Probably close to this order for dollar magnitude.
I believe, from the available information provided by both sets of operators, the conventional belt operating cost (includes maintenance costs) will be considerably lower than the cable belt.
Regards,
Lawrence Nordell
Conveyor Dynamics, Inc. ■
Conventional Conveyor Vs Cable Belt
Mr Nordell,
First of all, I am not an advocate for the Cable Belt,
I am a user, so the subject presents only a
technical interest for me.Our choice was made
20 years ago.
By the way, the calculations carried out 20 years
ago by REI/CC showed that the weight of the
belting and power consumption to be 10 %
higher than the same for the Cable Belt.
In addition, you do not know and did not take
into account the real route of our Conveyor
( horizontal curves, browses, etc ), so your
calculated cost difference could be a source
of confusion to other potential clients.
Michael Rivkin ■
Re: Conventional Conveyor Versus Cable Belt
Michael,
Why would you compare 20 year old technology with now? Surely, you believe some progress is at work. This includes Cable belt systems such as Ropecon.
I try to be an advocate of the owner. I do not lose sight of who pays the bills.
I came into this business in 1966. I thought this will not last. In 15-20 years, New technologies would replace belt conveyors. I now know, as reasoable advancements are made, that follow the same economic curves (laws) of competition for all products, if you do not advance the product, it will lose to competition. So, the obvious question is: what has Cable Belt advanced to stay in competiton?
Conventional troughed belts can claim 20 year advancements in:
1. power reduction on the order of 20-50%
2. strength increase on the order of 30-40%
3. life increases on the order of 100-1000%
4. reliablility and maintainablility > 99%
5. dynamic analysis and control - minimizes extreme risk
6. flexibility in use of horizontal curves > 100%
7. speed increases to over 12 m/s in tests
8. fewer components - idlers and pulleys
9. less noise; dust - environmental awareness
10. power strip booster belt - on strength fits all
11. light weight elevated structures
12. automated maintenance on the horizon
on and on.......
Keep the faith.
On thing is certain - in chaos there is opportunity.
Lawrence Nordell
Conveyor Dynamics, Inc.
www.conveyor-dynamics.com ■
Cable Belt V's Conventional Velt
As an ex Cable belt employee for approx 4 years and now a maintainer of approx 36 km's + of conventional belts (30 conveyors up to 3km's long and rated up to 10500 tph.) for approx 6 years I feel I should offer my comments on the subject above.
It is true that the vast majority of people are daunted when they first see a Cable belt system. I main reason I believe is that it is different to that of conventional belts and do not understand the requirements to operate it. It does not help when the major project managers of the world do not select a Cable belt for commercial reasons (most can design their own conventional system therefore eliminating Cable belt designers who are single purpose companies - 2 only I believe) However when both systems are broken down for the purposes of maintenance the systems are only a machine consisting of drives , rubber and cables. The main issue in my opinion therefore with relation to cost for maintenance is the leadership of the maintenance crews and the ability of the maintainers.
How ever Cable belt's require different maintenance !!!(as does any machine)
I have visited sites both here in AUS and overseas and have seen both Cable belt's and conventional belts in a poor maintained state with high maintenance costs.
My personnel view on selection of a Cable belt v's a conventional system is that of application. ie where the resource is located and where do I want to convey it.
Mr Rivkin's application for a Cable belt is a perfect example of application (I worked on this installation during my Cable belt years and is a credit to his team). However a particular Cable belt installation in the Phillipines would have in my opinion been more suited to a conventional design.(Again I worked on this installation and the maintainers battle conditions that have to be seen to be believed)
Cable belt's do have a place in this world as long as the application suits and people understand the maintenance requirements.
Stephen Rigby
srigby
Registered: May 03
Location: Newcastle AUS
Posts: 1 ■
Worsley Alumina Cable Belt
All,
A question about the Worsley Alumina Cable Belts.
What is the drive configuration of this system?
I understand there are two flights, (20.4 km and 30.4 km). How
much power is installed at both flights?
Is the 2*3300 kW and the 2*1700 kW powering both flights?
Kind regards,
Steven Moerman ■
Conveyor Convensional V/S Cable Belt
I appreciate very much the discussions you made in relation to the above mentioned subject.
I learned there are differences between the technology 20 years ago and the actual technology, but also the technical aspects mainly related to the type of cables (kevlars and others).
My main concern is related to the capacity, because that means wider conveyor belt and also very big bending moment in the center of the belt. For counterbalancing that high bending moment it is necessary a harder belt and probablly a very flat belt. What about capacity? at a maximum speed taken in account that also horizontal curves are needed.
I really think that the actual technology for cable belts are limited in capacity, let say less than or close to 4,000 mtph ???.
I will appreciate any futher comment in relation to this concepts direct to my e-mail if any. grosenth@codelco.cl
best regards to anybody and your interested comments.
Thank you very much ■
Worsley Pictures
Thank you dear Hans for your pictures.
regards ■
Re: Conventional Conveyor Versus Cable Belt
I am amazed that this thread is still running.
The last post, almost, mentions horizontal curvature along a cable belt. To develop curvature would probably introduce closer pitched linestand sheaves to maintain reasonable fleeting angles. Exit cost effectiveness!
Cable Belt used to propose directional changes using a single ropeway diverting around a horizontal sheave (or vertical axes if we prefer) system. A new belt then sat on the section of redirected rope. It was a drive free transfer tower: which sort of mitigates against the overhead expense of designing & building the transfer tower in the first place. ■
John Gateley johngateley@hotmail.com www.the-credible-bulk.com
Conventional Conveyor versus Cable Belt
Dear sir;
I will appreciate information regarding the Cable Belt system (high capacity, 4,000 mtph) and which are the main factors to be considered in making a comparisson between both systems, in addition to the known features and benefits named by Cable Belt such as: conveyor lengts, horizontal curve radii, reversibility, easily extension, environmentally friendly, etc.
Some info about maintenance, operating costs and capital cost?.
We are developing a conceptual study comparission for a length of 9,650 meters and total lift of 573 meters.
We have no experience specially in normal failures or operational and maintenance problems. Any comments will be appreciate, site to visit?.
Regards ■