Spotlight On Wire Sawing
Method(s) Used: Diamond Wire Saw with Hydraulic Actuated Rotation
Location: Detroit, MI
Detroit’s wastewater collection system and the main treatment plant serves more than 3 million people in 78 communities, making it the third-largest utility in the United States. The main wastewater treatment plant processes an average of 723 million gallons of sewage per day, with peak flows exceeding 1.2 billion gallons per day.
Wire Sawing Opens Up Wastewater Facility to Increased Flow
A recent project involved connecting new primary clarifiers, numbers 17 and 18, to an existing part of the wastewater treatment facility. To allow wastewater flow between an existing shaft (tank) and a newly constructed shaft, a 14-foot-diameter opening with tapered sides needed to be cut in a 5-foot-thick concave shaft wall. This opening would create a passageway between Shaft 4 and a tunnel leading to the new Shaft 6. With this modification, wastewater would flow from Shaft 4 through the tunnel to Shaft 6 and then on to the new primary clarifiers numbers 17 and 18. These new clarifiers had been constructed to increase the plant’s wastewater filtering abilities.
IPM began work in September 2003. Before customizing a wire saw for the job, IPM reviewed the job conditions. An existing 9-foot, 6-inch-diameter concrete bulkhead formed a portion of the 14-foot-diameter plug to be removed in Shaft 4 and the connecting tunnel. Access to both sides of the plug was limited. Operators would have access on the cutting side of Shaft 4 through an 8 1/2-foot opening in the roof slab and could gain access relatively easily in a normal cage. However, in the new Shaft 6, the only opening was 3 1/2 feet wide.
In-Place Machining team finished the job on time and within budget. “We were very satisfied, especially when considering the excess heavy steel encountered and the difficult work environment,” said Tim Beckman, Sr. VP of Diamond Wire Cutting Services at In-Place Machining Company. “There was not a single failure or disruption of the special wire saw rig.” Beckman attributed a few factors to being awarded the job. Specialty wire sawing is a major scope of In-Place Machining Company, and the price was below the originally specified method of water jet cutting.