Savings; an Added Bonus from CBC.
Case Study - Power Transmissions by David Brown Industrial Gearbox
Author: Tony Voiklis Power Transmission Technical Specialist
specializes in designing and supplying Power Transmission Drives and industrial
gearboxes to a wide variety of industries. Not only have they successfully
offered industrial sites significant purchase cost over rebuild cost savings,
but they have also offered dramatic power saving costs through their ability to
redesign current industrial gearboxes to more efficient gearbox options.
provides an example from a South Australian mining site where significant
savings were realised and quantified for reduced downtime, purchase price over
rebuild costs, power saving, and environmental, Carbon Tax, saving.
Background on Industrial Gearbox Upgrade
advice from the customer that the main drive gearbox on the Number one Primary
Conveyor had catastrophically failed. The failure of this industrial gearbox
had completely stopped production at this particular facility. CBC was asked by
the client to find a replacement industrial gearbox.
gearbox was an outdated David Brown Radicon Worm Wheel type industrial gearbox.
This particular model of David Brown industrial gearbox was not popular in
modern drive designs due to its high cost and poor efficiency. The supply of
this same David Brown gearbox was not possible on a short lead time. The
following is a breakdown of the status of delivery and cost.
|Item||Delivery Time||Cost |
| New David Brown industrial gearbox || 15 weeks || AUD $85,000|
| Overhaul existing David Brown industrial gearbox || 15 weeks || AUD $65,000|
CBC Power Transmission technical specialists
undertook a full analysis of the drive and found that the industrial gearbox
was rated to a maximum of 37.1KW, despite it having a power input of 55KW.
While the gearbox had been in place for many years, in recent times a larger
motor had been installed to increase output. This had lead to the failure of
the drive, which included Worm Wheel gear destruction. Hence, should CBC have
been able to supply an identical replacement David Brown industrial gearbox,
failure would have reoccurred.
Industrial Gearbox Upgrade
CBC was able
to redesign the drive to accept a Rossi Bevel Helical gearbox. This particular
industrial gearbox was lower in cost, and greater in efficiency. More
importantly, this particular gearbox had the rated capacity to suit the drive
motor. To adapt this drive to the conveyor and expedite installation, CBC also
fabricated a drive base plate. The following is a summary of delivery and
costs. Summary of delivery and costs is as follows;
| Item ||Delivery Time||Cost |
| New industrial gearbox || 3 weeks || AUD $45,600|
| Adapter base plate || 3 weeks || AUD $5,813|
| || TOTAL || AUD $51,413|
offered twice the mechanical capacity of the previous industrial gearbox, 77KW
versus 37.1KW, greater power efficiency, and improved features, such as Air
Sentry desiccant breathers.
Summary of Cost of Industrial Gearbox Upgrade
In order to quantify production cost savings, a
cost of downtime was required. The only official production cost analysis
available for this site was undertaken in 1990. The following therefore, in
today’s terms, is considered to be conservative.
production at this facility was costed at $6 per tonne. It operates
24 hours a day, five days per week, producing 2000 tonnes per 24 hour day.
At $6 per
tonne x 2000 tonnes per day = AUD $12,000 per day The customer
was able to mitigate some of the downtime loss by having employees take
holidays during the period of lost production. In addition, some planned
electrical maintenance work, 10 days in total, was able to be brought forward.
providing a delivery improvement, this industrial gearbox redesign provided a
lead time of three weeks over the best possible alternative option of 15 weeks
to rebuild. The saving was: 50 days ( 10
weeks) x $12,000 per day = AUD
Calculations are based upon 10 weeks due to the fact that two weeks of
electrical planned work was undertaken during this period as mentioned above.
CBC was able to supply the upgraded solution at a lower cost of $51,400 versus the lowest cost alternative option of $65,000. Therefore the purchase
cost saving was $65,000 -
$51,400 = AUD $13,600
Further Potential Industrial Gearbox Upgrade Savings
the 15 week option to rebuild the existing industrial gearbox had been
undertaken, another catastrophic failure was highly likely, particularly in
line with a conveyor jam up, as there was no fail-safe device, such as a fluid
coupling, on this particular conveyor. Therefore, the rebuild cost of AUD
$65,000 had potentially been saved within the first 12 months.
Bevel Helical Gearbox upgrade CBC engineered had a power efficiency of 96.5%.
The Worm Wheel industrial gearbox that was originally in place had a power
efficiency of only 65% when new.
words, of the 55KW input power, 35% was being lost with the worm wheel gearing.
This meant that the motor had to draw 35% more amps. This was both an
additional cost in power consumption and an environment disadvantage via
additional green house gas generation.
approximation, to assume a conservative 25% of the 55KW input power was lost,
or 13.75KW at the sites average power cost of 0.165KWH, the potential ongoing
annual saving on power consumption would be:
0.165KWH x 24hrs x 5 days per week x 48 weeks per year = AUD $13,068 per
Summary of Industrial Gearbox Upgrade
savings of this particular industrial gearbox upgrade is summarized in the
|Savings || Savings Cost|
| Production downtime saved || $ 600,000|
| Purchase cost saved || $13,600|
| Potential saving via avoiding additional failure
(annualised) || $65,000|
| Potential power consumption saving (annualised
estimate) || $13,068|
| TOTAL || $ 691,668|
and upgrade services on Power Transmission Drives can provide significant
options for a variety of savings. CBC has supplied, redesigned, or refurbished
industrial gearboxes and other drive components, including brakes. As well as
performing redesign and refurbishment on David Brown industrial gearboxes, CBC
have also upgraded a wide variety of other brands of gearbox and various gear
reducer configurations, quantifying the savings to the customer. These include
Flender and Bauer industrial gearboxes, as well as planetary and variable speed
In addition, CBC
industrial gearbox refurbishment services include the following additions
and/or upgrades for all types of current gearboxes, offering improved longevity
and problem solving.
- Air Sentry desiccant breathers for dust or moisture/humidity
- Sensors/Accelerometers for vibration analysis, including cabling and junction boxes to suit site applications and conditions.
- One Eye magnetic filtration options for exclusion of ferrous particles.
- Route cause failure analysis reporting.
- Sealing upgrades for all environments.
- Thermal insulation options for protection in hostile environments and energy saving.
- Drive alignment options, including onsite service.
- Vibration dampening options, including Rosta tensioner.
- Lubrication upgrades, including premium options for extreme environments via Kluber Lubrication.
- Perosity sealing of gearbox castings.
- Oil cooling systems/heat exchangers.
- Soft start options via Inverters or Fluid Couplings.
- Lubrication systems, including recirculation and kidney loop.
- Oil sampling ports.
Author: Tony Voiklis Power
Transmission Technical Specialist