Sand Etc,
Originally Posted by VinceS
G'day,
We have an application to lift sand at 2,640t/hr peak, 2,200t/hr nominal approx 10m vertical to take sand from a scalping grizzly discharge and run it over a 4m wide wet screen into a sump for pumping to downstream processing. This is a 24hr/day 10-15mtpa portable mining operation so reliability and robustness are key requirements.
I would appreciate comment on whether a bucket elevator or sidewall conveyor would be the most appropriate solution for this application. Given that the throughput rate is close to / just past the envelope for practical belt widths and speeds we are thinking a twin side by side belt with at least the head pulleys on a single shaft, probably with a center bearing, is the most likely configuration. This will also assist with distribution across the screen feed box.
The sand is 10% w/w water content (until discharged in the water filled feed box!). Density is 1.65 t/m3. Size is 98.5% 5mm or below with rogue lumps to 75mm.
Any suggestions in configuring the recommended mechanicals for minimum maintenance would be appreciated / a realistic guidance on what can be expected in this area. Thank you in advance.
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Based on what you have stated discussing this with the folks at conveyor dynamics Inc. and Dos Santos International are the folks you should contact on the board here.
As you stated it is vertical and problematic a bucket elevator will eventually be fighting to enter and exit the elevator pit due to spillage and clay.
Spillage will also effect a sandwich belt and its traction simply from slop just as a side wall belt would do so.
A pair of shallow flight augers 36-48 inches in diameter in a tube shell with a large diameter inner tube-24 inch to mount the narrow 2 inch flights would be a possibility with a pair of high torque gear boxes to power the upper and lower ends of the augers would work like water lifting auger used to raise river water to a water treatment plant.
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Seeing as you obviously have water to use-
The dumb as a rock approach involves less work and maintenance:
A pair of Gould, Wilfley, or Warman Rupp sand pumps with vertical discharge can do this as well.
these centrifugal pumps will either have inlets at the center line of the impeller the or bottom to pull and push the as long as there is adequate water.
The pumps are typically designed to be maintained in place with split cases to allow repairs, replacement and inspection of the pump impellers.
The pairing of 2 direct drive small dredge pumps in the 6 inch size probably would be the lesser problem as they are ment to move this type of solids laden water.
Using Victaulic piping and clamps speeds repair and maintenance as well. ■
Minimum Maintenance
I assume this is wet bank sand which has a high repose angle. If there will be sufficient moisture runoff that can destabilize the material on a 20 degree slope then the below concepts will need to be modified.
The lowest maintenance prone system would be a straight slope belt conveyor of ~ 30 m long x 10 m lift. It will take about 100 kW and 1500mm wide belt operating at 2m/s.
Other methods will also work such as: screw, bucket elevator, flexowall, et al. All of these products have the advantage of short length, exept flexowall.
Screw will be high maintenance with wear of flights and trough chute. Bucket will be difficult to clean and have carryback maintenance issues.
Flexowall must be loaded on an incline or you will not be able to clean it. Probably will not be able to clean it anyway.
Downside of belt conveyor is the added 20m length. It will pay big dividends with maintenance and spillage control provided you properly design the feed chute geometry to feed product at +/- belt speed. ■
Spread The Message.
Originally Posted by VinceSThe sand is 10% w/w water content (until discharged in the water filled feed box!).
Your thinking is quite productive. 
Distribution across a screen deck is an issue raised before.
I'd insert a dog coupling and have a dummy shaft ready. To get even better spread you could run a pair of wide cleated belts at a reasonably steep slope.
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Further Info
The key aspect here is that this plant will be relocated every three days so it needs to be big and boofy, with good tolerance for misallignment. We were originally asked to arrange a feeder from two dozers to run at 3,000t/hr up a 30m conveyor and over the wet screen. The gathering feeder to be used is a proven product for the application and will have a divergator at 75mm to pull out tree roots and rogue lumps from over excavation.
On a relocation the feeder will be set up first and a 0.5 - 1m deep trench cut up to it to give 2.5m working clearance. Then the screen / elevator / sump module pushed in and final aligned with Tirfors if required.
We had resisted the idea of an intermediate conveyor, whilst completely sound for the reasons outlined, as we have had experience with these in the past and find they are just not a long term viable answer in the field. Making a robust 30m long skid mounted conveyor to be pushed / pulled by dozers is still not a particularly appealing prospect. But it may yet be the best....!
We have been told today that flowability of the sand is not such a problem. We would need to see that quantified by the various acceptable methods to do this before relying on that statement. It is still not clear to me if the 10% moisture comes from wet bank or an arbitrary number to account for the fact that intermittently it will rain despite being in a dry area. Also we have been told that the addition of 20% to the nominal throughput was not really representative of what is needed, 2200t/hr is what they want it designed for.
I do appreciate the suggestions to just pump it in and will check that further. My initial reaction is that this is such an obvious thing to do that there will be a reason not to of which I am currently unaware. It has been said that they really don't want to pump it until it has passed over the screen. Nevertheless I would like to know what the percieved problems are as I think the issues of getting an adequate portable sump under the feeder could be overcome, maybe handling the mass flow of water within the required range could be problemmatic?
We do not have a lot of experience with bucket elevators but are very familiar with large conveyors. I am currently waiting for Braime to respond with technical recommendations for the application. The original purpose of this forum enquiry was to endeavour to fast track the decision process as we are being hassled for budget pricing next week to get to an order before Christmas if it comes together well. I had noted that the Flexowell (or more likely Pocket Lift) belt systems could do the job as well as a bucket elevator but really need to drive this thing to a definitive answer fairly quickly, but don't have sufficient direct knowledge of the issues with either of these methods to do so on solid experience!
I had ruled out the variants of sandwich conveyor as I really only think these are of merit for much higher lifts, but maybe should have another look at that. But really am looking for commentary that is based on a sound operational understanding of the compromises involved with the various technologies, if that is reasonable to ask. Thank you. ■
Re: High Capacity, Short Lift Steep Angle Convey
Everything can be measured and evaluated by degrees. Using a Sandwich Light conveyor can reduce the length to about 17 m.
Sandwich Light applies a very light low structure belt with high compliance on top of the product. It inhibits particle rotation and does apply some compressive strength from the top belt's weight. It can maintain stable inclines above 30 degrees. It can be cleated and will not increase residual spillage since it returns with the dirty side up. It will be the lowest cost solution.
Not a full Dos Santos Snake or HAC. It may be managable with the dozer. ■
Sand Etc.
Originally Posted by VinceSG'day,
We have an application to lift sand at 2,640t/hr peak, 2,200t/hr nominal approx 10m vertical to take sand from a scalping grizzly discharge and run it over a 4m wide wet screen into a sump for pumping to downstream processing. This is a 24hr/day 10-15mtpa portable mining operation so reliability and robustness are key requirements.
I would appreciate comment on whether a bucket elevator or sidewall conveyor would be the most appropriate solution for this application. Given that the throughput rate is close to / just past the envelope for practical belt widths and speeds we are thinking a twin side by side belt with at least the head pulleys on a single shaft, probably with a centre bearing, is the most likely configuration. This will also assist with distribution across the screen feed box.
The sand is 10% w/w water content (until discharged in the water filled feed box!). Density is 1.65 t/m3. Size is 98.5% 5mm or below with rogue lumps to 75mm.
Any suggestions in configuring the recommended mechanicals for minimum maintenance would be appreciated / a realistic guidance on what can be expected in this area. Thank you in advance.
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What Mr. Nordell and Mr. Panjang have said is very applicable to your situation-puzzle-hypothesis and the experiment and conclusion await.
Another option thinking out loud here is an old dredge scow-just bear with me; now-
1. You have X machinery that the client wants to move with earth movers.
a. you require a grizzly scalping screen, a much larger over size screen for the application would be advantageous simply from the point of less strain on the screen as it is of a larger capacity than required.
b. your pumping water anyway down stream after screening to move the sand to down stream processing.
C. The Victaulic brand fittings and piping are used for dredging around the globe and are very easy to use.
2. The semi mobile plant has to be strong enough to with stand movement and stress from pushing and or pulling by a wide blade dozer-assuming The D-11 size class of dozer.
3. The dredge barge would have a strengthened hull and, bow and transom
pusher blocks/chain anchorages for towing could be added on all four sides for the dozer blades.
4. dredge barge's are self contained with fuel tanks engines, centrifugal pump, winches to move it forward and back, left and right, etc. and the pumps are sized for huge tonnages of semi solids.
a. The barge would have the ability to stack all the components vertically
consisting of the over sized grizzly screen, water pumps etc. The water filled feed box could placed on the bow of the barge to allow installation within sensible engineering guidelines to reduce the possibility of tipping over from being top heavy.
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Thinking out loud here.
5. The four wire rope winches on the barge could simply be used to pull the barge forward using the dozers as an anchor etc. to reduce damage from the dozer blades pushing it.
6. The water could be recirculated continually in a closed circuit system and contained to reduce the mess acting as a conveying medium for the material being mined.
7. a WR Stamler or Mclanahan feeder could be used to load the grizzly screen
from the ground with an extended flight conveyor chute assembly. These units are very well built and are skid mounted and able to be moved by dozers with cables or chains and are used in wet environments on the surface.
lzaharis ■
High Capacity, Short Lift Steep Angle Convey
Without a doubt, the DSI Snake would offer the best technical solution. The discouraging thing is that with only 10 meters of lift required and the radius of curvature constraints the profile would not achieve a very high net angle. If we load at 15 degrees then begin our ascent along the transition curve we will reach the 10 meter height pretty quickly then we discharge at what angle we achieve, 45 to 60 degrees, but the net angle, from loading to discharge may be in the 30 degrees range. Still this will be much better then a sandwich light which is described a lot like the RAHCO overlay conveyor of the 1970's. You should either do it right or not waste your time. I do agree with Larry that for economics and reliability the conventional conveyor will likely offer the best solution in this case.
Joe Dos Santos ■
Re: High Capacity, Short Lift Steep Angle Convey
Hi
I would not use a bucket elevator - if you need to move every 3 days - things are going to get out of whack and you will have issues. I am assuming that each of these items are going to be dragged around.
I am not familiair with what is proposed but i think that a plain old belt conveyor will go...but you need distance.
I used to work in a mine with stope back fill - used to drag the cement feed/water mixer and belt conveyor around to each hole.
I was wondering if jet slingers could be used at the site - throw material up to stockpile???
Cheers
James ■
Re: High Capacity, Short Lift Steep Angle Convey
Sandwich Light is a conventional old belt conveyor with a light tough on top.
Glad to see Joe in agreement after much agony. I too would like to see the Snake do its trick. Unfortunately, this is a little short. ■
Clarification And Appreciation
I really do appreciate the high value comments being made here, some excellent thinking and the foundation of the ways in which we grow / spread the knowledge in the "game".
I would also say I have long admired the solid work Joe DosSantos did to get a high angle conveyor concept practically working and commercially sucessful. Several times I have put these up at feasibility / concept stage but projects sadly never wound up going ahead, ultimately people always seem to find a way to keep on truckin than doing the job properly! Unless they have to.
I have also clarified what is going on with the subject material. Basically it is dry sand in an arid environment that needs to be moved at 2,200t/hr. On the very rare occasions it rains they will deal with it, but don't want specific features included to accommodate it. The original spec sheet was compiled by a junior engineer who didn't realise the consequences of some of the "seemed like a good idea at the time" conservativeness included in the original info.
It also appears that routinely they will be mining through light vegetation and the tree roots and very occasional rock will add up to a noticeable qty. 44t/hr will come off the top of the screen if you take the figures given literally - it may not be that much but it will be more than half that I am told.
I enquired more about the idea of pumping it up. There are two basic resistance points here. 1) Just plain inefficient from an energy perspective given more than double the mass has to be lifted and it will happen less efficiently than via mechanical conveying. 2) There are a lot of miscellaneous issues that would need to be solved, some of which are covered off nicely in Mr Izaharis' comments. But we won't be pumping it.
Isn't the jetslinger suggestion a cool idea! It would need a cleated flat belt on the bottom of the chute and still we may have problems burying it. there would be other issues needing careful exploration too. However we are in a situation where we need to be using highly reliable well understood technology to apply to this project, and that could only happen if we could show where a similar system was operating and then get an operational sign-off of that. I have put in a jetslinger once and looked at other applications for them over the years - I suspect we would be pushng it to get the tonnage reliably, but definitely a meritorious concept!
The robustness and alignment of the twin bucket elevator or Flexowell / Pocket Lift concept is not really an issue as it will be integral with the screen support and we are talking about heavy 750 I beams and the like. The only reall issue will be alignment at the feed point off the divergator and ensuring that works. I guess I am not a lot wiser about choosing between these technologies from an experiential perspective. But the well seasoned prospective client has certainly warmed to the idea of a compact integrated elevating system over the more unwieldy portable conveyor.
We have an excellent relationship with McLanahan and are working with them in the development of the system as they will be providing the feeder end of the equipment. ■
Re: High Capacity, Short Lift Steep Angle Convey
Hi
We have both belt and central chain type elevators on site.
If the whole game is integral - then an elevator would not be out of the question.
I would be looking at a central chain - friction drive if suitable (top wheel drive) - this is more robust and not prone to belt drift (downtime trips). Aumund or Beumer etc. Have heard bad stories about twin chain types...we have Aumund and Beumer on site.
If you have two - then consider capacity at 60% each say - note that the usual design criteria is 75% bucket fill . takes surges. It is important to size drives for max denisty x 100% bucket fill - so you can still have main drive start under a bogged situations. Also bear ion mind chance to still operate with one elevator online > if 60% of flow sheet > then make sure that the rest can operate at this turn down.
You will need to consider maintenance - chain replacement (should be at long intervals - ours have been going for over 15 years), bucket replacement/servicing.
I do not know much about the sand - your buckets may need digging teeth at set bucket spacings...consider that the boot section will fill up with sand and this will be deadbox...if it goes hard over time > then this can impact the chain stretch/take up ....we have used air blasters with digger teeth.
Note that most unit are self standing - so loads will report to the bottom...and only lateral guides required. Note that chain is less tolerant of alignment compared to belt (plan view looking down - cross alignment plus skew alignment esp with only 10m of lift). A belt will have drift issues if the alignment is not right. You could ask the suppliers if they could look at CAT type chains (SALT etc) for the chain - as the top suppliers are German and if chain wear becomes an issue - then getting them will be a bigger one. Note - as you only have 10m - the client could reverse engg the system with a CAT chain - this will prob. mean a whole new set of buckets.
I would make sure that the elevator system has worked somewhere else before signing up....
Cheers
James ■
Sandwich = Rahco Overlay Of The 70'S
As I said, the Sandwich Light is the RAHCO Overlay Conveyor of the 70's. You still have to load the material on the open trough before entering the sandwich. You cannot increase the angle abruptly after the sandwich is formed, hence the radius of curvature constraints. So how does the sandwich light solve the problem?
Joe Dos Santos ■
Re: High Capacity, Short Lift Steep Angle Convey
Having an odd 30 minutes I thought I'd think about a bucket elevator.
So it's now 2200 te/hr with a lift of 10 m.
So according to me that would be a 160 kW motor. Chunky!
2200 te/hr @ 1.65 te/m3 is 1333 m3/hr. Big, but only equivalent to 1000 te/hr of wheat.
So maybe a belt and bucket elevator, I prefer to keep things like sand away from chains. As the sand is dry and free flowing lets say a belt speed of 3 m/s and use the biggest "Jumbo Starco" at the closest pitch of 5/m with a water level filling. This would give 540 m3/hr so 3 rows would give 1620 m3/hr. Maybe lower the buckets/m and/or reduce the belt speed. Modify the standard buckets to have Hardox 500 wear banding added to the front and side lips, topped on the top edges with chrome carbide weld deposit to get the best life.
This would give a bucket elevator with a plan area of about 1.7 m square.
Of course this is just one of a myriad possibilities. 
■
Special Bucket Elevator Spells High Maintenance
Sand against steel, high speed, short cycle time. This spells high duty, wear, O&M disaster.
Joe Dos Santos ■
Re: High Capacity, Short Lift Steep Angle Convey
Originally Posted by Joseph A. Dos SantosWarranty excludes wear and tare to replaceable parts, so good for spares business!
And doesn't the sand just slide down an inlet chute, drop into the bucket, drop out of the bucket and slide down an outlet chute?
But seriously,
1) the whole life cycle costing need consideration
Initial cost
Annual maintenance including bucket replacement
It can be that with planned maintenance and replacement of buckets it's not a financial disaster.
2) and the sand is lifted vertically in the minimum footprint, what else can do this? ■
Re: High Capacity, Short Lift Steep Angle Convey
I dunno about the "big-bucket" in the sky. Pencilling in the dimensions of this proposed big-bucket has to rank among the biggest around. Recall the volume spec'd is closer to 2600 t/h.
Dear Designer,
Do you have a bucket and flow rate in mind to tackle this project? A one second fill of the potential big-bucket at say 50% fill volume is quite impressive by my calculation.
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I contend a simple trough belt can do it with the blanket belt. I would almost be willing to offer it on consignment including the typical portable wheels with the guaranty of payment for performance. ■
Re: High Capacity, Short Lift Steep Angle Convey
25+ years ago we designed a range of bucket elevators for 250 - 1000 te/hr (330 - 1330 m3/hr), belt widths to 1.6 m wide, and which worked "off the drawing board", a very pleasing result. Even more pleasing when one 1000 te/hr unit actually passed 1200 te/hr when the feed control system went awry.
As to a design for this application, my first post (yesterday) gives one possible solution with the specification having been reduced back to 2200 te/hr of dry sand yesterday. Wet sand would be a different ball game! ■
Well, There Is An Answer!
I certainly have appreciated the debate surrounding this question. I have concluded that the answer to the original question as put is that neither would have been an answer!
Now that the clarification that nominal design rate is the actual design rate and, more importantly, that the sand is dry it seems the centre chain bucket answer is the most appropriate. I do not actually know if the flexowall / pocket belt configuration would work (I suspect they would), but it is plain that there is additional complexity and cost to deal with loading and discharge and we would only entertain that if the physical limitations forced it.
Thus we are now in the process of entering into an arrgt with Beumer to supply this equipment. Their initial recommendation is to use a twin 1m wide bucket, central chain configuration. Once we have final budget sign-off we will proceed with the details, indications are this will be later this month. ■
Re: High Capacity, Short Lift Steep Angle Convey
Originally Posted by VinceSTwin 1m wide buckets on central chains, that's not going to be cheap 
I wouldn't dismiss a belt and bucket on dry sand too quickly, as at least there are no chain joints for the sand to wear away at. ■
Well, There Is An Answer
I believe this forum would be interested in a report of success after one year of operation. I certainly would like to know how this turns out.
Joe Dos Santos ■
Belt / Chain For Elevators
As I would have mentioned earlier we have a lot of experience with conveyors. What that leads to is the knowledge that this game is 90% experience and 10% engineering - albeit that probably 50% of the 90% is knowing how to intelligently apply the engineering to work and having a clear sight of what the consequences are / might be in the varying operational and maintenance (and construction!) situations that will arise.
But in the elevator business, well, I did put a couple of small ones to fill batch mixing bins in Malaysia in the early 90's but that hardly qualifies me for much! Therefore I am really interested in what suppliers with deep experience are saying, as of course what practitioners that are well able to look beyond the occasionally blinkered views of suppliers. The key for me is to get to be playing in a paddock where all options are an answer, then we are just in the optimisation business where it is about criteria weighting and most probably a real mistake won't be made, subject to due care and attention of course.
Which is a long winded way of saying what Beumer's experience says is that the chain / belt decision is made firstly on heat then on material size. If there are lumps over 20mm they will recommend chain every time as they say these lumps will progressively damage the belts beyond an acceptable rate. We have lumps in the form of tree roots to 75mm - or whatever a divergator doesn't pull out and, despite that this is a relatively low quantity in the material stream, their strong advice is that this is an issue of consequence which drives adoption of chain over belt.
I do have open q's with Beumer re the operational wear life, maintenance requirements, and similar facilities in operation, but we will get to those in due course and I am not expecting any surprises. After all we are basically buying an "off the brochure" system as our application fits well within the experience base. We will also explore what other features may be prudent to simplify living with these things. I'm not sure what the choices will be but auto lube will go on, then it will be dealing with wear plate replacement, condition monitoring / whatever - I will be looking for their experience to lead us. As it happens the good Dr is in Australia at this very moment which will ensure our particular application gets properly looked at (not that I had a concern it wouldn't!)
Certainly happy to log a bit more detail here re what we do in the first place, as it is at least handy for others searching for a reference point re how the related topics were handled by someone else who didn't really know what to do any more than I did. When it gets constructed a page of photos will turn up on www.calsun.com.au well before the operational feedback is available. We don't bother updating the photos there much these days, except for pet projects (and this will be one!) as the website has needed a complete make-over for a while - it was pretty cool 10 years ago but is now overdue for a re-write. But of course we also are very interested in the operational experience gained so we will be looking for that feedback ourselves. So, if the photos turn up but I don't get back here please feel free to hassle me for the answer! I do, however, hope I will manage to remember.....!
PS: Braime did get back to us and declined to provide a proposal for a belt elevator. No clear reason given but their engineer I spoke to earlier in the piece calculated a 3.5m diam head pulley would be required. Despite asking three times I never got clarity on why such a large pulley would be required, however that was plainly not going to be an answer for this sort of application. ■
Re: High Capacity, Short Lift Steep Angle Convey
I have also used chain and bucket elevators and if temperature is involved they become the option of choice as when the material is large and lumpy.
In the case of an occasional large lump the choice is less clear cut.
How large are the lumps?
What are the shape of the lumps?
and most importantly
How many lumps are there?
It is possible for quite large rounded lumps to pass through handling equipment without causing any problem if they come through singly. A length of tree root is another matter!
With your chain and bucket elevator will it have a friction drive wheel or a toothed sprocket at the head? 10m is not very tall for an elevator and there is a view that you are more likely to get drive slip with on friction drives on shart machines than on tall machines. But sprockets are not without their problems ( https://forum.bulk-online.com/showth...t=16711&page=5 )!
What is the order of cost for your chain elevator?
If I had to guess, I'd think a belt and bucket machine with wear resistant features might be about 150,000 euros (but it's just a guess)
As to a 3.5 m dia head pulley, . I wonder what the design basis was for that? Perhaps if Braime read this they may wish to clarify ■
Steep Angle Conveying
We have a vertical pipe conveyor, "patent pending", and are designing for higher tonnage and higher lift. This could be a nice pilot plant for us. We want to build a full size short lift model. Are you still interested to go ahead with this project? We want to go eventually to 8000t/h, 100m lift or more.
Let me know,
Ingolf ■
Re: High Capacity, Short Lift Steep Angle Convey
A vertical pipe conveyor, could be a neat solution. How could you load that with a free flowing material? I guess the q is so obvious you will have an answer! Which I expect means the pipe needs to be formed and held while close to horizontal before radiussing round and up - otherwise something that looked like a reverse rathole would make for some interesting backward spillage pulses!.
The problem we would have here is that this site needs a "bankable" solution. There can't be any risk associated with it. When they're a mature operation looking to expand its a different story, but it wouldn't happen up front unless the emerging technology gave a massive / enabling boost to the operation.
For our conventional solution we will pull up on the south side of 200k euro, just not exactly sure how far at this stage! ■
Re: High Capacity, Short Lift Steep Angle Convey
Hi Vince
An elevator will cost a lot more than this.
Ask Buemer or AUMUND (agent is Ammermans and Partners).
Heat and lump size is Ok for the decision tree. But we have both and you should consider chain for - life, resistance to damage and perhaps less mis tracking (but possible issue with wear from misalignment) if the whole machine is going to be moved around...this is IMHO. I would ask the 2 main Germans suppliers to look at your issue and put their pecker behind their words - 2000tph is a lot. A previos post had a belt speed of 3m/sec - this is fast for an elevator > need to have centifugal discharge.
Beumer and Aumund belts are very $$$ and long delivery periods,..this is why i suggested an option to use CAT SALT chain. The belts have a special splice that requires their German technician to come and do for you in order to keep warranty - this is the weak point in the system.....sometime you have to have 2 splices as a result of these issues - short 10m section
For the chain - 10m is not much head for a friction drive..may need toothed drive.
Note that you will get impulse loads at the discharge esp from the drop/throw height > need to watch for fatigue on load receival items.
The only other option I could suggest is an inclined apron feeder/drag chain arrangement............????
Cheers
James ■
Agents Down Under
Well there you go. Aumund (www.aumund.com) state their closest agent is in Hong Kong, whereas it is really about 80km down the road from us (www.ammermann.com.au).
Beumer do list their local agent (http://www.beumer.com/htcms/en/about...sidiaries.html) whom is 160km south. We have submitted our budget based on Beumer's initial response but are awaiting details for confirmation purposes.
I am not too worried about discharge impact as it will be a tiled feed box set up with a weir on the discharge and an approx 1:1 by volume make-up of water which will cushion it well. We need to ensure relatively even feed to the 4m wide screen which should just be a matter of thinking through the correct water injection sizing and placement. ■
Re: High Capacity, Short Lift Steep Angle Convey
Hi
could you please let me know if a self-locking worm gear could be used for lifting??
Actually I want to make a goods lift for elevating to first floor. I have the self-locking gear box but think it won't work as it will lock itself in one position and will not reverse.
What should I do??
thanks a lot ■
Re: High Capacity, Short Lift Steep Angle Convey
Originally Posted by mazhurcould you please let me know if a self-locking worm gear could be used for lifting??
Actually I want to make a goods lift for elevating to first floor. I have the self-locking gear box but think it won't work as it will lock itself in one position and will not reverse.
What should I do??
thanks a lot
It would be more dangerous than its worth. if you are only moving goods from floor to floor it would be more cost effective to use a lifting table sized for a forkift and pallet.
a spiral conveyor needs lots of floor space and height to work. where a lifting table is much much simpler.
google (southworth lifting tables) ■
Re: High Capacity, Short Lift Steep Angle Convey
I have just read through all the suggestions offered and I would throw in a simple robust and sound method to achieve the requirements that is relatively maintenance free. Presuming there is ample water, then it would work well and not weigh greatly in mass. Gravel pumps and other types were mentioned but they are all prone to severe wear and require large horsepower. I have used both water and/or air jetting systems to pump over 1400 t/h using simple jet systems which were used to lift 30+ metres and gravel over 100mm lump size in 150mm bore case piping. The only wear is minimal in the vertical casing and the discharge hood plate was of Bisalloy and pocketed to keep some product so wear was mainly between product and not bare steel. If you have the bore casing laying on an angle, then wall wear does become prominent and cyclical rotation of the casing as the wall wears to get longetivity of the bore casing without holing.
At a local coal mine, they used 'Super Sucker' to bring minus 250mm rock up from the underground at 300 metres depth during the development of high methane coal bed 'grunging development' and did so successfully. Their power consumption at this site was horrendous but was necessary.
Hope this helps. ■
How To Publish A New Thread
dear all:
does anyone can tell me how to make a new thread here?
thanks ■
Re: High Capacity, Short Lift Steep Angle Convey
Did you not like the answer I gave you in May?
https://forum.bulk-online.com/showth...t=20160&page=2 ■
Gary Blenkhorn
President - Bulk Handlng Technology Inc.
Email: garyblenkhorn@gmail.com
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Offering Conveyor Design Services, Conveyor Transfer Design Services and SolidWorks Design Services for equipment layouts.
High Capacity, Short Lift Steep Angle Convey
Most appropriate high t, short lift steep angle conveying process
G'day,
We have an application to lift sand at 2,640t/hr peak, 2,200t/hr nominal approx 10m vertical to take sand from a scalping grizzly discharge and run it over a 4m wide wet screen into a sump for pumping to downstream processing. This is a 24hr/day 10-15mtpa portable mining operation so reliability and robustness are key requirements.
I would appreciate comment on whether a bucket elevator or sidewall conveyor would be the most appropriate solution for this application. Given that the throughput rate is close to / just past the envelope for practical belt widths and speeds we are thinking a twin side by side belt with at least the head pulleys on a single shaft, probably with a centre bearing, is the most likely configuration. This will also assist with distribution across the screen feed box.
The sand is 10% w/w water content (until discharged in the water filled feed box!). Density is 1.65 t/m3. Size is 98.5% 5mm or below with rogue lumps to 75mm.
Any suggestions in configuring the recommended mechanicals for minimum maintenance would be appreciated / a realistic guidance on what can be expected in this area. Thank you in advance. ■