New Milton Sand and Ballast is an independent aggregate producer and supplier offering a range of aggregate and concrete products; sporting and horticultural sands, soils and compost; merchanting supplies; and waste management services. Based in the United Kingdom, the company was started by a family of builders in the 1940s and has grown to become a large operation, now with three quarries, four sites/depots, one recycling center, four concrete plants and two builder’s merchants.
At its quarry in Christchurch, New Milton Sand and Ballast needed to replace a competitor’s primary rinsing screen that had reached the end of its usable life. The company’s biggest concern was retrofitting a new screen into the existing plant structure, as New Milton Sand and Ballast did not want to change the main frame on which the screen was installed.
New Milton Sand and Ballast also didn’t want to have a company try to sell it a whole new plant design since the rest of the equipment was still in good operating condition.
As the company began its search for a replacement screen, McLanahan reached out to offer a solution. This solution piqued New Milton Sand and Ballast’s interest, so representatives of the company went to see a similar McLanahan screen at a site on the Isle of Wight that has been in operation for more than 20 years.
“The comments that we got from the guys on site were great,” Paul Drayton, Production Director for New Milton Sand and Ballast, said about the visit. “They said dealing with McLanahan was second to none, on the end of the phone should you need them. The screen looked good, and the quality of the build.”
The feedback from the operators of the McLanahan screen on the Isle of Wight gave New Milton Sand and Ballast the confidence that McLanahan was the screen supplier to work with.
McLanahan engineers worked with New Milton Sand and Ballast to design an Inclined Screen that was tailored to fit into the existing plant structure. Besides taking measurements to ensure the perfect fit, McLanahan also interviewed New Milton Sand and Ballast about its pain points with the old screen to determine how to best design the screen to meet the company’s needs.
The solution was a 1.8m x 5m double-deck Inclined Screen outfitted with spray bars on the top and bottom decks that were tailored to alleviate challenges New Milton Sand and Ballast had with its old screen.
One of the challenges New Milton Sand and Ballast faced with the old screen was the clearance between the decks, which made changing the screen media a problematic endeavor. McLanahan increased the clearance between the top and bottom deck of its screen offering to improve maintenance for New Milton Sand and Ballast.
Through discussions with the New Milton Sand and Ballast team, McLanahan also learned that the old screen moved more violently at daily startup and shutdown, causing the screen to hit the discharge chute or the structure, which caused stress fractures and cracks in the screen. McLanahan designed the discharge lips of the new Inclined Screen so this wouldn’t happen in the future. It also allowed the screen to be a lot less noisier and move better than the old screen in that position.
Another issue the company had with the old screen was increased wear from the sand slurry mix hitting the first few panels of the screen media on the bottom deck. McLanahan decreased the aperture size in the first few panels to allow for even wear.
McLanahan also increased the aperture size of the spray nozzles so that they wouldn’t clog up from the grit and organic matter in the recycled water New Milton Sand and Ballast uses for rinsing the aggregate on the screen.
Other design updates McLanahan added to combat issues New Milton Sand and Ballast had with its old screen included ease of maintenance for the drive system, increased protection for the spray bars on the bottom deck to reduce wear, and extended bearing wear life.
New Milton Sand and Ballast was involved every step of the way, and when it was time to install the screen, Mr. Drayton said the downtime was minimal.
“It seemed very seamless the way they came in and they retrofitted this new screen for us,” Mr. Drayton said. “It sits in there and it’s chugging away quite happily.”
Although the screen was designed specifically for New Milton Sand and Ballast to alleviate the company’s pain points with its old screen, Mr. Drayton was most impressed with McLanahan’s customer service and willingness to work with New Milton Sand and Ballast to deliver a product that met its needs.
“The screen is a screen. It does its thing,” Mr. Drayton said, “however, I think the process that we had dealing with McLanahan from the inquiry through to getting the plans through, they came down and sat with us, made sure we were happy with the whole design, that we were kept up to date constantly with the whole process. It’s been a seamless installation.”
Even after installation, Mr. Drayton said McLanahan still makes a point to check in to see how the screen is operating, and they’ve had a great experience working with McLanahan.
“It’s always difficult to recommend companies, of course,” Mr. Drayton said, when asked about his experience with McLanahan. “Once we got in contact with them, we got the confidence right from the beginning of the design all the way through and even now.
“I think for us, we’ve got a lot of confidence there and we will be happy to use them again.”