Cement materials are very hard on valves, requiring them to be replaced at an unusually fast pace. This can get expensive. Manufacturers demand the availability of many types of diverters to address different material handling situations, especially those addressing abrasion.
A manufacturer of concrete mix and repair products in the United States approached Vortex Valves and Loading Solutions with a problem it was experiencing. Bucket diverters that were being supplied by a local fabrication shop to route gravel, dryer fines, and sand from a belt conveyor into individual product bins were not standing up to the extreme abrasion of the material passing through the diverter.
The diverters were expected to handle 60 t of material, 24 hours a day, five days a week, plus two 12-hour shifts during the weekend. Soon after installation, it was experiencing wear to internal parts, leakage of material to the off leg, and difficulty in shifting the bucket to divert flow. The diverters had to be removed and serviced on a monthly basis (sometimes in the middle of a product run). The wear was so severe that diverters were completely replaced every three to four months. Not only was it expensive to replace or rebuild the diverters, there were additional costs incurred from renting a boom lift to access the area of installation.
Upon assessing the application and the materials handled, Vortex began development of a bucket-style diverter that included key design features to address wear issues created from the abrasiveness of the materials handled. The diverters used at this facility experienced wear on the bucket, inlet, or body. They were also difficult to rebuild and maintain, as moving wear parts are not easily replaced in-line. Sealing fine particles from leakage to the closed leg was also a prevalent issue, due to reliance on a metal to metal seal design.
To assist the customer with its problem, Vortex created the Vortex Aggregate Diverter to overcome the common issues with bucket-style diverter designs and meet the demand of handling material such as sand, gravel, whole grains, and coal in gravity flow applications.
One of the main features of the Aggregate Diverter is its wear resistant bucket, which is constructed from durable AR steel. Since cross contamination of material was not an issue, Vortex pointed out the advantages of creating an additional honeycomb ‘rock box’ liner on the interior bucket and throughout the diverter. A rock box was designed to trap material so that subsequent material impacts on itself rather than creating wear and abrasion to internal parts. A ‘dead pocket’ deflector was suggested for the inlet to help minimise the wear on the inlet. Vortex also suggested that the bucket and chute leg liners be dead pocketed as well so the material would abrade against itself instead of the diverter legs.
The ability to perform maintenance on the valve while in service was a significant benefit, leading to the company selecting the diverter. Vortex made the customer aware that a side access panel is standard with its diverters. Internal inspection, maintenance, or replacement of the bucket or chute liners can be made through this access panel without having to take the diverter out of service, saving maintenance costs and production downtime.
The Vortex Aggregate Diverter was priced higher than the local fabricated diverters. However, the concrete company admitted that if this diverter could give it a life expectancy of six months without the constant repair issues, it would be worth it. Vortex also agreed to sell a diverter with a 90-day deferred billing to prove the diverter would work in the facility.
Ninety days after installation, the diverter was inspected. There was no significant wear and there had been no maintenance issues during the trial period. Eighteen months after installation, minor maintenance was performed on the original Vortex Aggregate Diverter. Additional diverters were ordered and the company subsequently standardised its valves to Vortex Aggregate Diverters.
This is part one of a two-part article written for World Cement’s May issue and abridged for the website. Subscribers can read the full May issue by signing in, and can also catch up on-the-go via our new app for Apple and Android. Non-subscribers can access a preview of the May 2016 issue here.
Read the article online at: https://www.worldcement.com/special-reports/30052016/new-solution-part-one-vortex/