Sound Off

A streamlined, sound-attenuated shell and a dual muffler enable the Warrior jetter from Spartan Tool to reduce operating noise

Waterjetters are indispensable tools for cleaning sewer lines. Manufacturers constantly make incremental improvement in this mature technology, and one of them is making them quieter, both to respect the neighborhoods where jetters work and to reduce workers’ exposure to noise.

Spartan Tool LLC has introduced the Warrior jetter, which has sound levels that fall below OSHA sound limits and so can be operated by employees without hearing protection. The machine uses the same engine and pump technologies as previous models but is sound-attenuated.

Tom Pranka, company president, and Brian Willis, territory sales manager, demonstrated the Warrior jetter for Darin Tracey of Frinks Sewer & Drain on June 9, 2008, at a strip mall in Rockford, Ill.

Walk-around

The Warrior jetter has a white, streamlined exterior. The trailer-mounted machine rests on two wheels and is 13 feet, 4 inches long, just over 6 feet high, and 6 feet wide. The machine’s molded fiberglass shell is lined with 2-inch-thick sound-insulating material. The shell splits along a lateral line — the front half tilts forward to allow access to the pump and engine compartment.

The muffler system further suppresses noise from the 83-hp diesel engine, which powers a triplex ceramic plunger pump that delivers 18 gpm at up to 4,000 psi. In addition to the conventional muffler, a secondary resonator further reduces noise. “It’s really like having a double muffler on your car,” Pranka says.

At the rear of the jetter under a horizontal cabinet door are the controls and hose reels. The unit includes a 500-foot, 1/2-inch pressure cleaning hose, a 100-foot, 5/8-inch supply hose for filling the 300-gallon water tank, and a 75-foot, 1/4-inch hose on a separate reel that can feed a pressure washer gun for cleaning or can be used for auxiliary jetting, such as inside a building.

The jetting hose reel can swivel out from the jetter to increase flexibility in feeding and rewinding the hose. Gauges measure water and antifreeze levels as well as engine fuel, oil, temperature and battery charge level. A four-position rotary switch sets the jetting pressure at 1,000 to 4,000 psi in 1,000 psi increments.

The jetter uses a clutch controlled by a toggle switch that can engage and disengage the pump instead of the pump running constantly, recirculating water when the jetter itself is not in use. The clutch configuration helps reduce wear on the pump.

“When you start up a jetter, you wear a pump over time if the pump is directly coupled to the engine,” Pranka says. “That pump starts turning immediately when the engine goes on. It will be cold, and the engine’s not terribly efficient. And the pump starts to wear. Instead, with this unit, you leave the clutch off, warm the engine up, and when you’re ready to jet you just put the clutch on.”

The sealed marine gauges are designed to keep out water. Toggle switches allow the operator to engage and disengage the pump, turn on and off an auxiliary light, and activate or deactivate a pulsing setting.

Operation

Pranka and Willis met Tracey behind the strip mall under an overcast sky with occasional rain. The block of buildings included operating and vacant establishments and offices. With Tracey’s assistance Willis filled the 300-gallon tank from a hose attached to the strip mall property, a 20-minute task. Pranka noted that the jetter can be filled from a fire hydrant in less than five minutes.

Tracey then opened a manhole, and Willis swiveled the jetter’s hose reel out, turning it 90 degrees from its resting place to enable easy feeding of the hose into the line. With the pump turned off, Willis turned on the jetter engine, then fed the jetter hose into the sewer line, flipped the toggle to engage the pump, and fed the hose upstream, running the jetter at the 3,000-psi setting. The hose traveled rapidly to 350 feet. Shortly before reaching the end of the run, the unit encountered a blockage that Tracey attributed to grease from a fast-food establishment.

Below in the manhole, the flow of wastewater had turned noticeably sluggish, emerging from the line as a dark, thick liquid. Willis flipped the toggle switch to engage the pulse control, a mode designed to break up blockages.

The toggle switch turns off the electronically controlled middle plunger of the triplex pump. This reduces the pressure but causes the hose and jetter to vibrate. “The vibration eliminates the friction between the pump and the hose by bouncing the hose as it moves down the pipe,” Pranka says. “It bounces forward against the blockage until it’s cleared.” After a few minutes, the character of the wastewater changed noticeably, running clear.

While the jetter was in operation, Pranka opened the cover to demonstrate the noticeable difference between the covered and uncovered jetter. When uncovered, he says, noise levels are about 92 to 94 decibels, which exceed the OSHA standard of 86 decibels, requiring hearing protection for the operator. Closed, noise is below 80. Throughout operation, the sound of the machine was a dull roar that was low enough to allow conversation. When Pranka raised the hood, the noise rose to a level where conversation could be heard only by shouting.

After reaching the end of the 350-foot sewer line run, Willis reversed course, engaging the reel rewind. In the process, he threaded the jetter hose through a pigtail- shaped guide built on to the reel to help lay the hose back evenly as it rewound. Because the guide is built in rather than a detachable component, Pranka says, there is no risk of it getting lost or left behind.

Willis flipped the pressure setting to the maximum of 4,000 psi for the return trip to complete the jetting procedure. In extending the hose into the line, Willis ran at a slower speed than normal, Tracey noted. As a consequence, the unit ran out of water before the jetter had completed its return trip.

After refilling the tank, the three proceeded to a second manhole, about 250 feet downstream from the first. After warming up the engine again, Willis engaged the pump, first at 2,000 psi, then clicked the pressure control to 3,000 psi. He sent the hose into the line up to the previous manhole, this time at a higher speed. Thejetter encountered no blockages and completed cleaning the line without incident.

Observer comments

The difference in sound between the jetter when muffled versus when unmuffled was pronounced. Tracey noted that compared to the other two Spartan jetters his business operates, the Warrior is “a lot quieter. It would be a lot easier on the guys.”

The look of the machine is simple and attractive. The instrumentation, relying on analog devices instead of electronic digital readouts, is easy to understand, and the labeling is easy to read. A streamlined body gives the unit a handsome look on the job and offers an inviting surface that the owning contractor or municipality can decorate with its logo.

Manufacturer comments

A wireless remote is available for the jetter, with a control circuit board that can be wired in plug-and-play fashion to the existing control electronics. Pranka says Spartan has seen little demand for the remote control. In addition to muffling the jetter’s sound, the streamlined cover makes it easy to lock the machine, safeguarding it from vandalism or tampering when unattended, Pranka notes.

The company chose marine analog instruments instead of digital readouts out of the desire for simplicity, durability and ease of repair. “This is out in the weather all the time,” Pranka says. “We wanted something we knew could take the constant water inundation. If you get too fancy with your controls, now your local guy five years from now can’t fix it.”



Discussion

Comments on this site are submitted by users and are not endorsed by nor do they reflect the views or opinions of COLE Publishing, Inc. Comments are moderated before being posted.