Page 61 - HUB-4 Magazine Issue 82

Quarrying News
The CleanScrape® forms a 3-D curve beneath the discharge that conforms to the pulley’s shape. Copyright © Martin Engineering 2023
Low-Bid Process and Life Cycle Cost
Although the policy is generally not explicitly stated by companies, the “Low-Bid Process” is usually an implied rule that is baked into a company’s culture. It encourages bidders to follow a belt conveyor design methodology that gets the maximum load on the conveyor belt with the minimum compliance to regulations using the lowest price materials, components and manufacturing processes available.
When companies buy on price, the benefits are often short-lived, and costs increase over time, eventually resulting in losses. In contrast, when purchases are made based on the lowest long-term cost (life-cycle cost), benefits usually continue to accrue and costs are lower, resulting in a net savings over time.
ProSpare improves
performance of belt
conveyors at one of the UK’s
largest Limestone Quarries
The quarry’s network of 100+ belt conveyors are critical to the success of the plant. Conveyors are known to be a hotspot for maintenance teams, with frequent maintenance and daily housekeeping commonplace.
The maintenance team recognised that further improving performance of these conveyors would provide significant payback, both in terms of improved efficiency and reduced maintenance spend.
ProSpare was invited to site to see if they could help with two troublesome conveyors:
1. A conveyor carrying <100mm aggregate suffered from excessive carryback. The build-up of material overwhelmed the undertrays and required clean-up several times a week.
2. A conveyor carrying fines experienced severe premature wear to the conveyor belt. Build-up in and around an under-performing sealing system would cut into the belt itself, resulting in replacement of the belt every 3 months.
To solve the problems, ProSpare installed a number of new components.
The belt with the carryback problem was fitted with Starclean PU pre-cleaner and tungsten secondary scraper. After 12 months operation the carryback problem has all but been eliminated, with little clean-up required from site operatives.
On the fines belt, the team upgraded the transfer point sealing system to Spill-Ex and installed a Starclean secondary scraper. 9 months on, the belt is still in good working order, tripling the life of the belt so far.
These successes led to the creation of a program of conveyor improvements. The ProSpare engineer devised the program for conveyors in target areas to solve specific conveyor issues. It included training for site maintenance staff and site vulcanisers in best practice operation and maintenance procedures.
In this period, the client has seen a vast reduction in carryback and spillage, reducing clean-up requirements and keeping more of the product within the process.
For more information visit www.prospare.co.uk
Conclusion
Engineering safer conveyors is a long-term strategy. Although design absorbs less than 10 percent of the total budget of a project, Engineering / Procurement / Construction Management (EPCM) services can be as much a 15 percent of the installed cost of a major project, additional upfront engineering and applying a life cycle-cost methodology to the selection and purchase of conveyor components proves beneficial.
Safety-minded design at the planning stage reduces injuries by engineering hazards out of the system. The system will likely meet or exceed the demands of modern production and safety regulations, with a longer operational life, fewer stoppages and a lower cost of operation.
www.hub-4.com September/October - Issue 82
| p61 |