June 2016, Vol. 243, No. 6
TechNotes
Ergo Tamp: A New Beat in the Street (Work) Scene
At Gas Technology Institute (GTI) in the Chicago northwest suburb of Des Plaines, IL, the ubiquitous task of cutting into street pavement to make various pipeline and utility repairs and then restoring the roadway is a complex effort that has spawned much attention and research over the years. Efforts by GTI researchers like Khalid Farag, a geophysicist, and Dennis Jarnecke, an engineer/project manager, have led to minimally invasive and more economical ways to get the job done.
Besides a lot of added costs, field work crews’ time and environmental impacts, too much of the street-breaking work historically has resulted in long-term pavement failure. In a nation where deteriorating road infrastructure is a $170 billion annual maintenance and repair challenge, the work of GTI and various equipment innovators is important stuff.
“When pavement cuts are not properly restored, they can lead to bumpy rides, a scarred and mismatched checkerboard streetscape, premature pavement failure and potholes,” Jarnecke wrote last year in a technical paper submitted to an industry conference, along with Marshall Pollock, with Utilicor Technologies Inc. in Toronto, Canada.
Concentrated in the distribution sector of the U.S. pipeline space, the broad swatch of maintenance/repair work in streets these days increasingly is done with smaller cuts to improve efficiency, cut costs, and minimize traffic/pedestrian impacts. It is what GTI and others in the industry have perfected into “keyhole” pavement cuts. The approach now widely applied has spawned related technology advances in tools and methods used.
Slinger, WI-based MBW Inc. is one of the innovators, developing a vibration-suppressed pneumatic tamping device that its creators say is aimed at “taming” one of the industry’s most disliked and physically abusive compaction tools. It is touted as having both operator and operations advantages. MBW has named its patent-pending device Ergo Tamp.
The increasing use of pneumatic tampers is coinciding with utilities and municipalities’ increased use of the keyhole approach, reducing excavation size to an average of 18-24-inch holes. Industry sources indicate that this practice has resulted in considerable savings in time and money. Traditional compactors, such as vibratory plates and rammers, are too large for the smaller excavation approach. Thus, the pneumatic tamper gets the nod.
“Smaller street cuts are definitely becoming more the norm, and this tool gives them greater mobility during compaction,” said Rick Gramoll, a MBW manager, noting that there is the possibility of new requirements for compaction around pipes – not just above them – that would further enhance the value of his company’s new tool. In any event, it is clear the name of the game moving ahead is being able to operate in a small footprint and still meet code and safety requirements.
Colorado Springs Utilities’ (CSU) Randy Pollette is familiar with Ergo Tamp from a tool maintenance standpoint, and said he likes what he sees. The small engine and lead mechanic at the tripartite (electric, gas and water/wastewater) municipal utility found a broken internal part in the device and reached out to MBW for a replacement. He received it quickly and got the wounded tamper quickly back in the field.
With traditional tampers that Pollette comes across in his Colorado shop, he often uses his left hand to operate, he said, because the older devices will invariably help wind his watch. Through a big grin Pollette adds: “The new ones don’t move very much, if at all.” In other words, forget them for watch-winding.
MBW in 2016 is developing a shorter model, which Pollette endorses because there isn’t enough room in a lot of the utility’s service trucks to store the long-handled model. “Looking at them, it’s a clumsy looking tool. I tell our guys to be careful how they store them in their truck beds, “he said.
The long-handled model is 74 inches in height, weighs 37.5 pounds (17kg) with a 6-inch diameter. Ergo Tamp operates at a recommended pressure of 100 psi. Air consumption is a minimum of 38 cf/m with up to 800 blows/m, but the operator advantage comes from its 70% reduction in vibration.
“This 70% reduction in hand/arm vibration assumes some variation with the changes in compaction conditions. “The vibration absorption system easily handles the range of amplitudes typical of pneumatic tampers and is cooled by a constant flow of compressed air through its working mechanism,” Gramoll said.
This is not anyone’s grandparents’ “polo tampers, pogo sticks, bouncing betties” or anything close, according to MBW’s description, or that of many of its customers in the energy sector.
At Milwaukee, WI-based WE Energies, the Waukesha Service Center started with one of the new MBW tampers and it has since added a second one, according to Matt LeDuc, gas operations supervisor, talking to P&GJ in mid-March. LeDuc notes that the general reaction among the users in his Midwest utility operations is “overwhelmingly favorable.”
MBW maintains that making the pneumatic tamper “tolerable from an operational point-of-view” makes users less prone to terminate a compaction effort before reaching a satisfactory geo-technical result.” When the compaction is improved, the incidence of pavement failure goes down markedly, according to industry sources. Further, the equipment puts less wear and tear on operators. A tradeoff is often longer compaction times for the added comfort and other operating benefits.
When he returned from assisting a crew at Baltimore Gas & Electric Co. (BGE), technical specialist Tim McMullen offered some other insights on the Ergo Tamp, for which BGE has invested in 10 devices, purchasing them late in 2015, and quickly getting used to the new tool. The utility demonstrated the tool for its workforce before making its commitment.
“The reports from the crews using Ergo Tamp have been positive with a noticeable vibration reduction to their wrists, elbows and shoulders,” McMullen said.
BGE is one of the customers requesting shorter versions of the device to ease storage in the beds of utility pickup trucks. McMullen indicates he is pleased with the responsiveness of the tool maker, and lauds the manufacturer for being “receptive to any further customization requests we might have, such as a kidney-shaped plate for better tamping around overhead poles.”
Although it is just one part of the keyhole approach to pavement cuts, the overall effort on a macro level is being addressed by organizations such as the Federal Highway Association (FHWA), which has commissioned past studies that demonstrated how pervasive road deterioration was from old pavement cutting/restoration methods. “Keyhole coring and reinstatement is just a better way,” GTI’s researchers maintain.
At CSU a gas crew supervisor was interested in the tool, so he arranged a demonstration in Pollette’s shop. “We ran the tamper on the floor on a horizontal rubber mat,” the chief mechanic remembered. The gas construction department was smitten. It purchased nine of them at over $1,300 each, according to company sources. “That response was just from the demonstration,” Pollette said. This was mid-2015.
Next, CSU’s directional boring supervisor ordered one for each of his five crews. He made this decision after using or seeing the instrument, Pollette said. More recently, one of the wastewater crews saw a tamper in action, and had Pollette purchase one for its operations at CSU. By Pollette’s count CSU was deploying 15 Ergo Tamps in early 2016.
One of the CSU crews uses keyhole technology for minimizing the holes it digs in the street. The crew bores 18-inch holes and then vacuums out all of the dirt down to a gas or water main to find an existing utility or add cathodic protection and then has to rebury everything.
This is a 6- to 8-foot-deep hole that they have to reach down into with a pogo-stick tamper. “They seem to think this one is going to do it for them,” said Pollette, noting he was still awaiting feedback on this application.
Overall, Pollette sticks to the facts as described by his coworkers. The tool is a taller tamper that takes some getting used to, he recognizes. “It is taller than most of the ones you see on the market. The trigger is around the same height and you don’t get the recoil from this tamper that you get from most.”
The taller profile offers two advantages, according to MBW officials, who stress them in their marketing literature:
- It is above the traditional chin-height, eliminating the possibility of the operator being hit in the jaw, which happens periodically with older types of tampers.
- With the Ergo Tamp, an operator doesn’t have to bend down, eliminating possible back problems.
“This does not reduce the time required for compaction, but it doesn’t lengthen it either,” according to Gramoll. “The goal we had when we developed this tool was to keep all the positives and get rid of the negatives.
He and others make the point that utilities typically doing compaction are going to make a tool like this standard on its distribution field trucks. Not all of them do compaction work, and that’s “a whole other story,” Gramoll said. For ones that do, the numbers vary. Usage by these companies is several times a day, he said.
Priced competitively with other comparable products ($1,300 range), MBW sees the Ergo Tamp fulfilling its expectations and goals from its design and development, offering major safety and ergonomic advantages compared to industry standards, as Gramoll described them.
GTI is now testing the device, and MBW engineers are waiting for some additional feedback. Since the research organization’s work over the years has helped nurture the keyhole pavement-breaking process that has now been widely verified and promoted for its effectiveness, it is fitting GTI should provide third-party input on the Ergo Tamp.
Excavation and pavement restoration costs can be reduced by as much as 87% when deploying new and safer construction techniques, such as the keyhole coring, and reinstatement approach that has been perfected and proven during the past 20 years, GTI’s Jarnecke wrote in his paper.
As far as MBW is concerned the Ergo Tamp can be counted as an extension of that success story.
Comments