For nearly three centuries, Colchester, Conn., has been a market center for the region. Located between the industrial, commercial center of Greater Hartford and the burgeoning recreational centers of Southeastern Connecticut, the city is one of the fastest growing communities in the state. Today, its population stands at more than 14,000 people.
Like many growing communities in the U.S., Colchester faces challenges with a water system that was installed in the early 1900s. While considerable progress has been made by the city’s water department, there are no valves in key areas of the city, such as a busy business district with restaurants and retail stores.
To help address this problem, Water Superintendent Steve Klobukowski contacted the Jack Farrelly Co. of Bloomfield, Conn. Bob Farrelly, vice president of services for the company, is a specialist in line stopping and installing valves while the water system is “under pressure.” The Jack Farrelly Co. uses several methods of flow control, line stopping, valve insertion, pressure tapping, etc.
Advanced Valve Technologies (AVT) presented the company with the EZ Valve system, which is a technology developed specifically for under pressure valve installations. The system’s easy installation allows for strategic resilient valve installation in less than one hour, using a minimal hole entry size. This makes the system ideal for traffic-sensitive streets and highways, and emergency situations. The valve uses an all ductile iron body, which conforms to AWWA spec. C509, and has the same number of turns as a standard AWWA valve. Unlike most AWWA valves, however, the valve actually expands when compressed into the main, which allows for bubble-tight sealing.
Farrelly thought this technology could provide a solution to many problems created by the other methods employed by his company. To give Farrelly a chance to evaluate the EZ Valve system under actual “live” field conditions, AVT was contracted to install one 8-in. EZ Valve in the Colchester water system in conjunction with the Jack Farrelly Co.
Installation overview
A typical EZ Valve installation includes the following steps:
- A technician cleans the pipe surface and coats the pipe with a food-grade lubricant for gaskets to ride on without tearing the sealing surface;
- The valve assembly (a precision machined ductile iron casting) is installed around the pipe;
- After the valve body is bolted to the main, the resilient wedge gate is inserted into the valve body;
- Once the valve is assembled, the power feed drive unit is installed to the valve and the pipe;
- The valve assembly is filled with water for hydrostatic pressure testing;
- Technicians install a temporary valve to allow an EM cutting system and mill cutting unit to be installed and removed while under pressure;
- The EM cutting system cuts a slot 120 degrees across the top of the pipe, which allows the resilient wedge gate to be inserted into the pipe;
- The chips created from the cutting are removed from the inside of the pipe through an exit hose attached to the valve body, so they do not clog downstream equipment;
- The cutting unit is removed, and a threading completion plug is screwed into the valve body through the temporary valve, allowing the temporary valve to be removed; and
- The valve is then rotated into the upright position, and the thrust restraint bolts are installed to prevent movement. The resilient wedge is automatically aligned to the milled slot created by the cutting unit on the top of the pipe.
After installation, the valve is ready for use. The entire process takes an average of less than 45 minutes. The EZ Valve operates exactly the same as an AWWA valve from street level, with the same number of turns and the same feel as other valves.
Satisfactory results
The Colchester installation was performed in one hour with no disruption of the city’s water service. In fact, the job took place on South Main St. (Rt. 85), in front of a major fast food restaurant chain, during the busy lunch hour, with no complaints.
Phil Gaudette, chief operator of the Colchester Water Department, said, “The EZ Valve is a ‘true valve,’ and with just the small slot cut into the top, it does not weaken the pipe. In fact, with the valve body being made of ductile iron, it actually strengthens it.”
“The EZ Valve is simply a great product, and we will be specifying it for future work here in Colchester,” Klobukowski said. “I particularly like the fact that no chips are left in the pipe after the tapping [slotting] operation; they are all flushed out during the operation. No other system does that. My crew couldn’t believe how quickly the installation was done, and they are also very impressed with the end product.”
“Less time, less work for my employees and less excavations are required, not to mention that a better end product is left for our customer,” Farrelly said.
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