Carstensen Contracting using its Allu screener crusher bucket to help lower the pipe into the trench for placement.
In late summer 2012, Carstensen Contracting Inc., located in Pipestone, Minn., learned of an opportunity to bid on a pipe-laying project in Oklahoma. Prior to bidding the project, Carstensen Contracting searched for a screener crusher bucket that would work in the rocky terrain and allow it to reuse the material on site, thus allowing it to underbid other contractors who would have had to haul in bedding material.
“We install 200 to 400 miles of water line annually,” said Ricky Carstensen, company president. “Last year, in a push to keep key employees busier in the winter, we started bidding jobs in Nebraska, Kansas and Oklahoma.”
Carstensen did some research and talked to contractors who owned different types of buckets. Two of the contractors told him they had tried several buckets, but the only one they had any success with, and the only one they would buy in the future, was the Allu screener crusher bucket. Satisfied with the other contractors’ first-hand reports of success with Allu’s bucket, Carstensen contacted Allu Group and purchased one. Carstensen Contracting successfully bid the Oklahoma job in September 2012 and began work on the project in the spring of 2013.
“We were significantly cheaper than the other bidders because of that one particular bidding spec,” Carstensen said. “You could either import bedding from a source about 30 miles away, or you could screen and use the existing material by taking the rock out of it. We were the only one that bid with that thought process. It virtually saved the project for us, because we didn’t have the added expense of using dump trucks to haul in the bedding.”
Allu makes more than 100 models to fit any size excavator, loader, backhoe or skid steer ranging from 1 to 5 yd. (.7 to 3.8 cu m) bucket capacity. For this particular job, Carstensen purchased an Allu DH 3-12-25 screener crusher processing bucket and mounted the processor on a Komatsu 210 excavator.
“The bucket works extremely well in dry material, but after the tremendous amount of rain that fell in Oklahoma this spring, it proved to work just as well in wet material,” said Carstensen.
The Oklahoma project involved the placement of water lines ranging in size from 10 in. (25.4 cm) in diameter to 2 in. (5 cm) in diameter buried at a depth of about 36 in. (91 cm). To make sure the pipe was protected from any damage once it was buried, the trench was dug to a depth of 40 in. (101.6 cm) and a width of 24 in. (61 cm).
Carstensen Contracting brought in a dozer equipped with 66-in. (167 cm) teeth to rip up the rocky ground, followed by a backhoe, which dug out the actual trench. The Allu screener crusher bucket followed to screen and crush the existing soil and place it back into the bottom of the trench as bedding on which to lay the pipe. The pipe was then set in place by a loader and covered with an additional 8 to 10 in. (20 to 25.4 cm) of existing material that also had been screened and crushed. Though the screener crusher bucket didn’t get rid of the rock completely, it produced a smaller gradation so that none of the pieces were large enough to harm the pipe. The existing material left over was then used for the backfill, with the larger pieces being placed on top.
Carstensen Contracting originally purchased only one bucket, but while working on the Oklahoma project it was so impressed with the first one that it bought two more, and a subcontractor rented another one for a total of four on site.
“Allu’s customer service has been incredible,” Carstensen said. “The integrity of the company and its representatives is what sold us on the bucket. They are there to take care of us — the customer. A representative was on site for four or five days making sure the bucket was going to work for us. We never had a glitch. It worked exactly the way the company said it would and has kept going to this day.
“This project will be completed by early fall 2013, but we plan to use the buckets in future applications,” Carstensen said. “Our production is better than anticipated because of the buckets, which is great. They have been performing well; absolutely no problems. Everyone who watches them work is amazed. Even the engineers and inspectors are impressed with the way the buckets are performing.
“When we bid the project,” Carstensen added, “one of our competitors asked me to share the information I had given the engineer about the Allu bucket. I did, and a couple days later he had one. The Allu bucket has made quite an impact in Broken Bow, Oklahoma.”