Truck-mounted vacuum and jetting systems are essential tools in sewer maintenance and can be adapted with relative ease for hydroexcavation.
Yet for many smaller communities, an investment in a full-size combination unit is difficult. Furthermore, some work settings call for a smaller, lighter machine. Especially for those users, SRECO-Flexible Inc. has developed the Versa Vac 1000 PD, a trailer-mounted vacuum unit equipped with a water pump to power a jetter wand for hydroexcavating and power washing. (The machine is available without the water system).
SRECO-Flexible, with headquarters in El Segundo, Calif., and manu-facturing in Lima, Ohio, demonstrated the Versa Vac unit on Nov. 19 for public works employees of the City of Lima. Demonstrators were Jon Gotchis, director of international sales and marketing; and Eric Carlson, an assembler,
Walk-around
The Versa Vac unit is mounted on a two-axle trailer. It has a carbon-steel, two-part tank with an 800-gallon (4-cubic-yard) capacity for debris and a 200-gallon freshwater compartment. The model demonstrated had a hydraulic vacuum boom equipped with 40 feet of rigid vacuum tube (a manual boom is available). The inside of the tank has an epoxy-based coating that inhibits rust.
The nozzle pipe for the vacuum hose and a series of extension pipes are stored in brackets around the outside of the tank.
The vacuum system is powered by a 1,400-cfm Roots blower. The water pump is a triplex plunger system rated at 3,500 psi/4 gpm. Gotchis says it is designed strictly for hydroexcavating and power washing, not for sewer jetting. The machine also has a decanting system, powered by the same engine that drives the blower and the water pump. The decanting system allows water to be drained from the debris tank while the system is in use, reducing excess water weight and allowing more room for debris. The machine was powered by a 99-hp John Deere diesel engine at the front of the trailer.
A series of controls and meters are on the right side of the unit, secured behind a hinged metal door. Analog meters monitor the tank vacuum, pump pressure and water pressure. Switches control work lights, the boom, and the water and vacuum pumps. Levers enable the operator to open the hydraulically locked tank and to lower and set three hydraulic stabilizer feet.
Another lever allows the operator to shift the wheels under the trailer forward when the machine is empty and backward when it is full or filling. This allows users to distribute the weight evenly for more stability in towing, depending on whether the tank is full. A third lever allows the operator to engage a vibration system that loosens debris clinging to the inside of the tank to make it easier to empty.
A handheld control tethered to the Versa Vac with a wire cable can be used to control its operations in the field. A wireless remote control also is available.
Operation
The demonstration consisted of two parts: using hydroexcavation to dig a hole for access to a water line to diagnose a repair problem, and using vacuum to clean leaves and debris from a storm sewer catch basin.
Carlson towed the Versa Vac behind a Chevrolet Silverado pickup truck from the Lima factory to O’Connor Avenue and Northwold Street in a residential neighborhood.
Gotchis gave the city crew members observing a brief description of the unit’s features. Using one of the control levers on the side of the machine, he released the four hydraulic locks on the rear door of the debris tank. Once the locks were released, he used another lever to open the door at the tank’s rear and display its interior.
Crouching inside the tank he pointed out a hammer-like device that can be used to vibrate the tank and loosen debris clinging to its inside. He stepped back outside and returned to the control panel, where he moved the lever to operate the vibration hammer, which made a loud, staccato, banging noise.
A city crew member then outlined with white spray paint a 3-foot square surrounding a curb box. Gotchis used the wireless remote to swing the boom around to the rear of the truck from its forward-facing resting position. Carlson maneuvered the truck to better position the unit relative to the painted outline, and Gotchis used control levers to lower the two rear and one forward hydraulic stabilizing legs to secure the machine on the street.
Jack Huber, utility field services scheduler for the city, explained that a leak was suspected in the water line about 3 feet below the curb box. Digging around the curb box would allow the city crew to access the line and diagnose the problem without the risk of damage to the line that would go with mechanical excavation.
Carlson screwed the jetting wand, with a pistol grip handle and trigger along with a secondary side handle for the other hand, onto the water hose. He flipped a switch on the machine’s side control panel to engage the water pump.
Meanwhile, Gotchis removed the nozzle pipe from its storage bracket and attached it to the hose. Pressing buttons on the wireless remote he engaged the vacuum blower, and grass underneath it stood straight up as the suction began.
Carlson and Gotchis then set to work hydroexcavating the area inside the painted square. As Gotchis held the nozzle about an inch or two above the square, Carlson activated the jetter wand and pointed, aiming a stream of water at the soil. The water saturated the soil, and the vacuum nozzle began sucking up the wet crumbs of dirt. Over the next hour, Carlson held the jetter wand with both hands as he moved it from side to side, carving down into the earth. Gotchis followed close behind with the boom, holding it as it sucked up slurry from the hole.
Midway through the digging procedure, Gotchis switched from the remote control to the cable-tethered control unit to maneuver the boom. He later explained that the heavy clay soil and the cold temperatures combined to make the remote less responsive than it would be under warmer conditions or in sandier soil.
When the hole got deeper, Gotchis and Carlson stopped digging for a time, removed the nozzle, and added an extension pipe between the hose and the nozzle, latching them into place.
The vacuum unit efficiently removed the mud from the digging site. After about an hour and 15 minutes, they had dug to a depth of about 3 1/2 feet to clear the water line. Lima crew members removed the curb box pipe resting atop the line, then posted warning cones around the hole until workers could diagnose and repair the leaking valve.
When digging was complete, Carlson washed down the nozzle using the jetter wand. After stowing the extension pipe, nozzle, vacuum boom and hose, and placing the jetter hose and wand on the sides of the tank, he towed the unit around a corner to a catch basin filled with dead leaves. There he and Gotchis removed the grate from the basin.
Once Carlson had maneuvered the Versa Vac unit into place, Gotchis used the remote to bring the boom back around to the rear of the trailer and attached an extension pipe. Carlson latched the pipe in place and activated the vacuum pump again. He lowered the nozzle into the catch basin. As Gotchis engaged the blower with the remote, Carlson held the boom low over the leaves and debris as they flew up from the catch basin into the maw of the nozzle.
After a few moments Gotchis again substituted the tethered controller for the wireless remote unit. Once the basin was emptied, in less than 10 minutes, the components of the unit were stowed, and Carlson then towed it back to the SRECO-Flexible Lima factory.
Observer/user comments
It took the demonstrators about one hour and 15 minutes to hydro-excavate the hole in near-freezing temperatures. Between the cold weather and the heavy consistency of the soil, the wireless remote was less effective than it would be in sandier soil.
While the Versa Vac is described as relatively quiet, the machine demonstrated made sufficient noise to make hearing protection desirable. Jack Huber of the Lima public works department said he particularly liked the adjustable-axle feature. He noted that while the machine might be too small for his community’s needs, it looked well built and rugged and potentially useful for a small community for which a larger truck would be unaffordable. “It seemed like a good solid machine,” he said.
Manufacturer comments
The Versa Vac is designed as a low-maintenance machine, Gotchis says. For example, little mechanical lubrication is required except for grease points on the boom and on the door latches at the rear of the tank. Antifreeze can be injected into the pump at the end of a work day in cold weather to prevent it from seizing up.
SRECO-Flexible believes the Versa Vac fills a niche for customers who might not be in a position to invest in a combination truck or who have use for a smaller- footprint, less expensive supplemental machine. Feedback from customers is that the unit is “a very stout, very solidly built, well-put-together machine,” Gotchis says.
