Repair or Replace a Bucket Elevator?

If the buckets are on a chain verify the clearance in the bearings of the chain.

This is a belt bucket elevator.

In any case, if the chain of a bucket elevator had problems I would replace the chain. it doesn't give me arguments to advise on the purchase of a new elevator (or not)

Previous poster nailed the essential:

Do mechanical inspection of the components;

are the gears worn excessively,

are the buckets themselves work excessively

how many visual patches can you find

Apply these principles to the specifics of your equipment.

I agree, however, concerning bearings there are currently two trends in this kind of application: 1-Maintenance Free parts, i.e. ceramic solid lubricant bearings, 2-Sensor bearings, most of the time vibration controlled or alternatively temperature controlled.

There is another general trend which is accoustic monitoring (condition monitoring) of your production line. This means setting up a system to record the accoustic output of your production line and monitoring any change in the accoustic levels.

Try this link which may give you some insight:

http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V57-3YJYGS3-5&_user=94608&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000007138&_version=1&_urlVersion=0&_userid=94608&md5=1148f39417717ed79f66d8ea63322ee1

Maybe another article but free?

Does this mean you can not access it? If you want I can send you the article by e-mail if you are interested. It is in pdf format.

Dutchy

Sorry for the late reply, I have been computer deprived for a while.

If you have it available, yes, please send me a copy of that article. Thanks.

Availability of parts recently replaced two pieces of equipment. The manufacture was no longer in business. The cost of down time would have been more then the cost of replacements. Some of the parts that needed to be replace where linear rails. The equipment was manufactured before they set standards. Some of which was welded in to the structure.

Well, in South America there aren't any standards for material handling equipment. The thing we have closer to standards are the designs of Kepler Weber, which everyone has copied, but still we find differences.

In My Opinion, no matter it is a waste of time or something else, you need to do some inspection, based on your findings then decide the next step i.e. repair or replacement.

Do the inspection as others have stated. Does the company do its own maintenance work or is it jobbed out? Check with your employees and see what they can remember. If it has become routine to patch it back together to make it another day they can tell you. They can also tell you about the hidden patches holding the thing together that you cannot see from the outside. Sometimes the lines of communication breakdown between the workers and the management. Unless management has to sign off on expensive parts they tend to be unaware as to the increased "routine" work required to keep a machine running. At the same time remember when asking a mechanic (like me) about a whether a machine needs replaced they (me) are also thinking about how much less work it will be to keep a new machine running. A little adjustment and some oil once and a while and it's good to go. Not pulling a power head or drive unit and rebuilding it can start to sound pretty darn good.

They are not my employees. I am a distributor of material handling and grain processing equipment. This customer of mine called me to know what they can do about that elevator that keeps giving trouble. For start he asked me if I have used elevators to sell.

At first I thought to tell him I don't know a ***** of maintenance, but then I thought that there are so many of my colleagues doing the same stuff and getting away with it, that at least I am smart and honest and won't do any harm.

Getting from the mechanics a recommendation for a new elevator would help my business for sure, but I don't want to grow a reputation of manipulating my customers into buying new equipment. I want to be known as the guy to call for honest and real help.

The maintenance manager of the customer told me they do preventive maintenance. I can't say how much preventive it is if they just check everything before the season starts and then work until it breaks down.

I am very glad to see your straight forward good ethics.

I wish you luck in all of your endeavors.

Inspection is never a waste of time IMO. Even if I have maint. records I would hardly ever replace a good working part or piece of equipment without first doing an inspection and deciding if it is necessary. Maint. records are good to give indications that an inspection may be needed and to let you know when to buy replacement parts or which parts you should keep in stock. If you replace equipment based entirely on past history of failures you could be wasting allot money by disposing of good equipment. Now with this being said if you do have a large component fail or that you find is getting close to failing then it could be time to replace the other parts in the equipment while it is down just to prevent an equipment outage later. All of this should be decided by analyzing the data you get when you do your inspection, parts availability verses new equipment costs, down time costs, etc.

Hi Gussosa.

For elevators that are not extremely critical the preventative maintenance would be based on inspection. For an elevator that is very critical there are some items you might replace even before the visual inspection shows they should be replaced. Without maintenance and inspection records, manufacturers data for individual component life is your best bet. Two items that fall into this critical category, may be the belt and the wheel bearings (head and tail). I consider these items critical in a critical elevator because (1) when the belt breaks it takes some time to get the old one spliced and pulled back in or even more time for a new belt and (2) when a head or tail pulley bearing goes out often times the elevator will keep running, the wheel will tilt running the belt over to the side which may cause it to catch and break.

For all elevators (critical and non-critical) the things you would routinely inspect are: head and tail wheel bearing condition, gearbox condition (are all the oil seals still good), feed plate/dump plate condition, belt condition (are the bucket bolts pulling thru and is the "rubber" showing small splits), bucket wear, drive belt/sheave condition (if this type), is the belt running in the center of both wheels, and head/tail wheel condition.

Inspection records over time can often tell you when to do shut down repairs before a catastrophic failure.

I haven't been able to find any information on the expected life time of the components. The manuals of the manufacturer just say general things about maintenance, when they bother to say anything. The advice usually is lubricate, lubricate, lubricate... but not excessively.

Your advice is the most informative piece of text I have ever seen in this industry.

My first idea, before going to the site to look at the elevator on next Tuesday, is to check if it still aligned perfectly vertical and the condition of the pulleys. If my customer needs to replace the leg sections because of misalignment (which causes early deterioration of the buckets and the belt) and the pulleys, then it is probably cheaper to buy a brand new elevator. There isn't any discount for buying the whole package (I simply sum the prices of the leg sections, the tail and the head) but freight and taxes can make the package deal cheaper.

I am not sure how big this elevator is but I have been in charge of rebuilding many in the 100' to 150' lengths at the mill work in. These are hot lime bucket elevators and they utilize a chain system instead of a belt because of the temp. they run at and because of the caustic environment. They consist of a few major parts" motor, gearbox, chain and sprockets, buckets and housings. While it is true that these chain elevators need to be aligned correctly they have a huge tolerance in all areas except the motor/chain/sprockets area. What I am saying is that they can wear a huge amount and still be in good working order as long as the lubrication is done. I have many times changed out the buckets and not do anything to the chains/sprockets or visa versa and they will run for years with no other repairs if lubricated correctly. I think after you do your inspection then you will find some components worn and in need of replacement but many others that are fine to run. I also think you will find doing a total replacement will be more expensive than completely rebuilding the old one. When repairing bucket elevators you need a crew of strong hard working mechanics with common sense, maybe one good millwright to watch over the line up of the motor/gearbox and chain and a leader to do an inspection and determine, plan and manage the course of work. I also usually use a small crane to pull the chain out or feed in a new chain and try to do the assembling or disassembling on the ground. Although bucket elevators are pretty easy mechanically to fix they can be real nasty projects because they are usually very filthy and greasy pieces of equipment IMO

Thank you for the kind words.

Much of what we are all saying here sounds a little "doom and gloom" but on the positive side, I have seen elevators that are lightly loaded for their size (moving low density and low abrasion material) that have ran for many years with no repairs other that head and tail shaft bearings.

Your coming inspection should be very telling, especially if you can estimate the total run hours or at least the date it was put in service.

If you want to ascertain the estimated service life of the belt but the manufacturer isn't available, you may try to find other belt manufacturer or distributors and determine the service life of their comparable belts. Many belts are specified by the number of plies of material, the thickness, the material type (rubber, PVC, urethane, etc) and the durometer of the elastomer.

IMHO you should inspect to see if the repairs can be made to your equipment to get it back into production. Making repairs to keep using a piece of equipment is not a waste of time and most anything that is replaced with new parts is not going to give you a problem for awhile. Then, you should use maintenance tracking software to keep records from here on out. These records are more useful for preventive maintenance than determining whether to replace a piece of equipment or not. If management wants a new shiny bucket elevator, well, that is a different matter. If you are dealing with corrosive materials or acid and are having a lot of wear then it may be cheaper in the long run to replace your equipment but this is more of a time sensitive thing as to the projected lifespan of the equipment and whether it is leaking like a strainer and straining like the Grinch's mutt or not. Having repair records will still not assure the amount of time your equipment will run before repairs will be needed. I have seen some pretty awful looking bucket elevators, mixers and automated equipment continue to trudge right along productively for years with a little TLC.