FEECO recommends keeping a number of bucket elevator parts on hand to facilitate a quick change out in the event of a failure. What follows is a summary of these parts, as well as helpful tips in minimizing downtime, and the information original equipment manufacturers (OEMs) will likely require in fulfilling spare parts requests.
The Importance of Having Bucket Elevator Parts On Hand
As with any industrial process equipment, keeping a spare parts inventory is a critical aspect of an effective preventive maintenance program. A vital piece of equipment in any handling system, the failure of a single bucket elevator component can keep an entire operation offline until the issue is resolved. As such, having the right spare parts on hand often means the difference between hours and weeks of downtime. This is especially true given the volatility of supply chains in recent years; a part may be unavailable or have weeks of lead time.
The result can be financially devastating; lost production, unfulfilled contracts, higher maintenance and labor costs, and more. The rush charges associated with emergency fulfillments further add to costs.
Wear-Critical Bucket Elevator Parts
The following components are considered wear-critical, meaning that a bucket elevator either cannot or should not be run without them. Some components may allow the elevator to continue operating, but risk potentially catastrophic consequences if allowed to do so.
Bearings
As bearings facilitate rotation of the belt or chain around the pulley or sprocket in the head and boot sections, a failed bearing will render the unit inoperable. As such, bearings should be replaced preventatively, before they have a chance to fail.
In addition to risking an unexpected shutdown, a worn bearing will put additional strain on the motor and other components as a result of increased friction.
Indications That a Bearing Needs Replacement
Bearing life can vary significantly depending on the unique operating conditions, with a service life anywhere between two and 20 years. Settings in which fugitive dust is a problem put bearings at greater risk, especially if the material is abrasive, as dust can infiltrate the unit and cause added friction.
FEECO recommends keeping an eye on bearings through regular inspections; if either heat or excessive vibration are present, it’s time to replace the bearing.
Data Required to Replace a Bucket Elevator Bearing
If enquiring with the OEM, the bearing part number is typically sufficient, barring any desired changes.
If soliciting new vendors, the following information will typically be required:
- Shaft size
- Housing bolt spacing
Chain/Belt
As with bearings, if the chain or belt fails, the bucket elevator will not be able to continue running. Unfortunately, belt and chain failure is not uncommon and when it does happen, it can take several days of down production to repair. The failure of a belt or chain can also result in damage to other components.
Here again, preventative replacement of any worn or damaged components is critical.
Indications That a Chain or Belt Needs Replacement
For both belts and chains, visual inspection is the only way to identify a potential problem. Regularly inspect the belt or chain for indications of visual wear; with belts, make sure the front and back cover, as well as any splices, are in good condition. Chain wear is often obvious, with what looks like a polished indentation where wear is occurring.
Check all hardware attaching buckets to the belt or chain as well. If a fastener fails and the bucket is allowed to hang on its remaining fastener(s), the elevator may become jammed, and failure of the remaining fastener could also occur, allowing the bucket to fall.
Data Required to Replace a Bucket Elevator Belt or Chain
Again, the OEM will be able to pull parts data based on the serial number.
A vendor other than the OEM may request the following data:
- Horsepower
- Elevator max load
- Material being processed
- Chain dimensions, if applicable
- Belt specifications, if applicable (width, thickness, covers used)
It’s important to note that if failure is occurring more frequently than it should, it may be time to upgrade to a more heavy-duty belt or chain, or have a qualified service technician inspect the unit to determine the root cause of the frequent failures.
Sprockets & Pulleys
Failure of sprockets and pulleys is unlikely, but these components can become worn.
Indications That a Sprocket or Pulley Needs Replacement
A worn sprocket is fairly obvious; in viewing the tooth profile from the side, a worn sprocket will exhibit teeth that are no longer symmetrical. Where the chain rides on the tooth, some concavity will be visible.
A slipping belt typically indicates a worn pulley.
Data Required to Replace a Bucket Elevator Belt or Chain
To replace a sprocket, the vendor needs to know the following information:
- Number of teeth
- Bore diameter
- Type of chain in use
To replace a pulley, the vendor will likely request the following:
- Pulley diameter
- Belt width
- Pulley “style”
- Shaft diameter
- Bushings
Drive Components
If either the motor or the reducer fails, the bucket elevator will be rendered inoperable. As substantial (and costly) components of the unit, regular maintenance as recommended by the manufacturer should be a top priority; neglected oil changes and poor housekeeping can allow fugitive material to infiltrate and damage the drive assembly.
Failure or damage may also be the result of an under-powered design, in which case the design should be re-evaluated prior to replacement.
Indications That Drive Components Need Replacement
Inconsistent or irregular operation, as well as auditory abnormalities, could be indications that the motor or reducer are in danger of failing.
Problems are particularly likely if maintenance has been overlooked or proper lubrication neglected, both of which increase the potential for failure in these components.
Data Required to Replace a Bucket Elevator Motor or Reducer
If the serial number is not sufficient, the nameplate can typically supply the model information.
Shafts
The head shaft serves as the drive shaft, while the boot shaft is typically mounted on a gravity take-up, tensioning the chain/belt while the head shaft turns the elevator.
Inferior material selection or defective fabrication of either shaft may result in inadequate strength for bearing the load of the bucket and chain/belt assembly. Regularly operating at overloaded conditions can also put stress on the shafts, causing failure.
A shaft failure prevents the unit from operating and can result in significant damage to other parts of the elevator.
Indications That the Shaft Needs Replacement
Unfortunately, shaft wear leading up to a failure is not overtly obvious, though some wear may be visible; typically in the event of a failure, operators will hear a loud noise and the elevator will likely stop turning.
Data Required to Replace a Bucket Elevator Shaft
Manufacturers are likely to require a shaft drawing in order to quote a proper replacement.
Buckets
While elevator buckets are often not considered wear-critical, they do merit mention. Damaged or worn buckets are not likely to be problematic, but will eventually cause an issue if not addressed. Similarly, operating without the full amount of buckets can have real consequences.
An elevator with missing buckets reduces efficiency and if severe enough, could cause a major bottleneck in the process. This is particularly true of centrifugal elevators, which are automatically fed through a feed chute.
In the absence of a bucket, material will still be fed into the unit, with the bucket following the absence picking up most of the feed. However, some material will inevitably end up falling into the boot and could build up and impede bucket rotation around the boot pulley if not continually cleaned out.
Tips for Managing A Spare Parts Inventory
Managing a spare parts inventory can be tricky and unreliable without the right systems in place. FEECO recommends the following tips as a way to streamline inventory management.
Consistently Keep Records
Documentation is often half the battle when it comes to a solid parts inventory program. Whether through an inventory system or a spreadsheet, keep detailed records of parts on hand, as well as their corresponding serial numbers and critical specs, preferred vendor, and any other critical information. The associated Bill of Materials (BOM) is an essential reference for such data.
It is also helpful to keep a record of order history, frequency of replacement, any maintenance work conducted, and the like, as this can help in maintenance and inventory planning.
Partner With a Reliable Spare Parts Provider
Establishing a good working relationship with a reliable vendor can make all the difference in requesting and obtaining parts on a timely basis. If not working with the OEM, be sure to carefully vet potential vendors for reliability, timeliness, and ease of working with.
Have a System in Place
A standardized process followed by all personnel is essential for streamlining inventory management. This typically includes a work order process for requesting and obtaining parts, as well as a system that provides transparency over this process to avoid duplicate work.
Conclusion
Having the right bucket elevator parts on hand often means the difference between hours and weeks of downtime. Conduct regular inspections and train all personnel on what to look for in recognizing potential problems. Develop a solid inventory management program to keep wear-critical parts such as chains/belts, pulleys, drive components, and more on hand and standardize the ordering process.
In addition to being the industry leader in manufacturing heavy-duty, custom bucket elevators, FEECO offers a comprehensive spare parts and service program to keep your bucket elevator running efficiently and reliably. For more information, or to request a quote, contact us today!