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Stainless Steel Bucket Conveyor (or tube chain) 1

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sewerguy

Chemical
Nov 6, 2002
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Hi, I am looking for vendors for a bucket elevator or tube chain conveyor of 316LSS construction (possibly 304SS), rising maybe 40 feet vertically within a plant. Material is somewhat like coal ash.

Other mitigating factor is it will be in Italy although US companies would be considered.

Grassroots applications - cost, delivery time (plus shipping time), ability to support application will all be factors considered.

Other info - I would be interested in any input on possible other types of conveyors to do this application, also why stainless steel makes it harder to find vendors.

Appreciate any responses - Sewerguy
 
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I have designed a number of similar applications using bucket elevators, en masse and full volume conveyors for coal ash and similar materials. Fabricating in 316/304 is normal for these applications and currently available.

kiwi98j@excite.com
 
if you want to solve your problem cheaply by finding a local italian supplier + installation contractor , search for 'WAM' on the internet. They are a major italian manufacturer of bulk handling equipment. I have worked a lot with the local country representatives of this multinational , their equipment is really great , but the after sales (project documentation , spare parts manuals) is usually shit. However , they are pro's on transporting all sort of materials with all sorts of equipment , using all sorts of techniques. I am sure they will be able to supply you various technical solutions to your simple problem , and be the cheapest due to local fabrication.

Otherwise , take a peek at , they also can help you solve your inquiry. They have sold SS screw conveyors for coal ash transport and are active all over europe.
 
One local vendor proposed a vertical screw conveyor, which may be appropriate if you have a well known and well behaved solid (like coal ash), but as a first of a kkind design our materials may come out with irregular sizing or possibly a bit wet/sticky. Am looking to be pretty conservative for first one of these.

Any experience with vertical screw conveyors to be shared? I am more familiar with inclined screws, generally kept at an incline < angle of repose. Vertical screw sounds problematic to me.

Note also temp may be 120 to 130 C, and even releasing some interstitial water or other vapors as it rises.

Really appreciate both your responses, and any further comments you may have.

Sewerguy

 
I never have engineered vertical screw for sticky powders , but I have seen a few of those working in a huge sludge treatment plant. That plant was developped for the evaporation of waste water out of mud residues coming from an adjacent major urban sewagewater treatment plant , to obtain dry organic balls fertiliser sold to the flower industry.

The screws were manufactured at Dinamec ( ), diameter 1000 mm , lenght 13 meter vertical , outlet on top , material SS304. Huge beasts. Tel. +32 9 367 94 94 , time GMT +1. Call them for advice , Mr Andre Geeroms , if he is still working there (was general manager).

WAM is also manufacturing those items.

The material was like wet compressed dirty mud , just as you would expect when having sewage residues scrapped from the bottom of the decanter tanks of a sewagewater treatment plant , residues being compressed in horizontal screws with rapidly decreasing thread step distance toward the outlet , for water removal thru top holes made in the tube around the screw , prior gravitary injection into the vertical screw conveyor.

They worked very well , although they told me that it was difficult to maintain them , given the specific mechanical construction and heavy loads applied to the bottom screw bearings , who had to support all the upwardly displaced product mass + screw mass itself. Given the dimensions of the beasts , the loads must have been impressive. They basically had two for each process line , who were put to work alternatively , the one on rest being 'maintenanced'.

I also would make sure there are easily accessible openings foreseen on top of your building roof , with permanent hoisting system foreseen on a steel structure above the outlet of the vertical screw systems , to be able to extract the screw from the screw tube or electrical motor gearbox + bearing housing for maintenance , or if something blocks inside it (sabotage by fired personel , have seen it on other occasions).

I personally would use only SS304 , because I deduce there is no salt or other aggressive caustic product in your mixture. If the SS304 is thoroughly welded and the welds properly passified and polished afterwards, it could go on for ages , given that you take precautions to keep your screw systems out of reach from rusting metallic parts or unprotected steel items during transport , installation and maintenance afterwards. It is not for fun that serious equipment manufacturers have completely separate SS and plain iron work shops , with separate non-mixable rollbanks and saw&cutting machinery for each steel type , and take care to very well wrap they SS equipment in protective bubble plastic sheets before calling in the careless transporters.

And finally , you can foresee a contract clause basically stating 'no cure , no pay' , and supply the italian supplier on your cost a few 2 ton closed big bags of your wet coal products to let him have the opportunity to make realistic inhouse tests on a scale model. They all have that somewhere stashed , a leftover model that was used to conduct test for other shit products , so you always can ask them to supply you a video tape with the proof that your product worked well in their 'labo' , that with the contractual clause should give you the confidence to go for it.

The alternative is probably not in bucket elevators, if your product is as sticky wet as your are stating. You only will have a clogged top outlet , recirculating continuously the same product that can't escape the bucket elevator due to continuous outlet clogging.

A closed chain conveyor would do the job perfectly , but will take much more place and I fear , cost a lot more than a duo vertical screw set. A belt conveyor is another solution , although the cleaning issue with your product makes it not advisable to use open belt conveying.

I personally would try the vertical screw model , if I had a space problem in my production room. Otherwise , I would go for an expensive chain conveyor for certain work reliability and take the arduous maintenance of such a system for granted.

However , it is your money and your time. :)
 
There just a hand full of conveyor manufacturers in the US that make sanitary or SS conveyors, bucket or otherwise. Two of the largest SS bucket elevator manufacturers are:

Meyer Machine
San Antonio, TX

Key Conveyors
Wala Wala, WA

Good luck,
Benni

 
Hi. I just happened to pick up this thread whilst I was checking our hit position in the search engines. We are UK based and have worked on a number of tube chain conveyor projects. I can confirm that there is a good chance that they would be able to elevate to your requirements (obviously we will need to know more about your product). We have direct experience of handling / elevating both dusts and wet products with these conveyors. Hope the response to your thread has not come too late!

 
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