Prep to Solve Wear, Safety, Monitoring Issues during Production
In the October issue, a number of plant and plant component original equipment manufacturers (OEMs) shared tips for the upcoming winter maintenance season readers will experience in North America. Their advice is something asphalt mix producers can refer to at any time of year to do some pre-planning. Also take a look at the concepts coming to the forefront with the offerings OEMs have on the table in this month’s product gallery. For example, the folks at HammerTek Corporation, based in Bethlehem, Pennsylvania, have recently provided a wear solution to Plant Manager Curt Stein in Allentown, Pennsylvania. Let’s take a closer look at the project information they submitted:
Sealmaster is a global supplier of pavement maintenance products shipped to customers in over 50 countries through more than 100 distribution centers. The company’s Allentown, Pennsylvania, plant uses silica sand as a filler to improve durability and add skid resistance to its line of pavement sealers. The 60 mesh (250 micron) sand arrives by truck with a pneumatic trailer equipped with a 1,000 cfm (0.47 cu m/sec) blower. A length of 4-inch flexible hose connects the trailer to the 4-inch schedule 40 pipe of the silo, which is routed 20 feet vertically, 7 feet horizontally and then downward to feed the silo, requiring two elbows.
The company has been offloading sand at this location for about six years, but, according to Stein, “We had problems since day one. As soon as it began to turn, the sand would erode or eat through the sweep elbow and eventually just shoot out the side.
“We went to a heavier elbow, but that didn’t work. The sand just ate through it within weeks. Then we went to a concrete-reinforced elbow. Within a couple of months, it ate right through the inner steel lining, through the concrete, through the outer steel lining and shot out again.”
The recurring problem was frustrating, expensive and difficult, as the repairs had to be made 25 feet in the air. Because the elbows were welded in place, replacing them incurred significant labor and downtime.
“It took three people––somebody on the ground to monitor safety, somebody in the air, and someone operating a fork lift or a man truck. In the early days, because it was a direct replacement, we’d have to cut off the sweep elbow and weld in the replacement. The guy in the air would also have to handle the welding equipment,” Stein explained.
“Later, we used bolt-on flanges thinking if we’ve got to replace the elbow, let’s make it easier. We did that, but every couple of months we’d have to remove the elbow and bolt on a new one, which still incurred downtime and labor. That’s when I contacted HammerTek.”
Unlike conventional elbows that rely on material impact to change direction, the company’s Smart Elbow® design employs a spherical chamber that protrudes partially beyond the desired 90 degree or 45 degree pathway, causing a ball of material suspended in air to rotate. Since the ball of material rotates in the same direction as the airstream that powers it, incoming material is cushioned by the ball’s rotation, and is gently deflected around the bend.
The deflection elbows prevent sand from impacting the elbow wall, which has eliminated elbow failure. Blow-outs, which previously shut the conveying system down every few months, have not occurred in years.
“In terms of payback, you have the direct expense of materials, your labor and the downtime, but more importantly, you don’t have people working 25 feet off the ground handling heavy steel pipes,” Stein explained. “I have another pneumatic system for powdered clay, and if those elbows ever wear through, I will employ the same solution.”
Additional OEMs have solutions for increasing reclaimed asphalt pavement (RAP) percentages, shoring up components, increasing safety in operations and more. The next few pages give a sampling of what’s available and I encourage you to let these companies know you found them through AsphaltPro magazine. Also peruse the advertisers throughout this publication for additional products that are set firmly in your wheelhouse for the specific goal of enhancing your bottom line. Let these partners know you appreciate them supporting a publication that brings you new and focused information all year long. Dive in!