Holston Gases has been family owned and operated for well over 50 years, serving customers from 25 locations in four states. “Our mission is simple; To take care of our customers in the timeliest fashion possible,” stated Robert Parsons, Holston’s Operations Manager. “That strategy covers distribution in industrial, medical and specialty gases.”Automation Is The Future Standard
In 2012 the 25-branch distributorship moved its original Tennessee headquarters to a new state-of-the-art facility. Equipped with a new Weldcoa 82-ft.-long palletized, automated cylinder-fill island, the facility has become a show-case for Holston. The technology package includes audio and visual communication of fill status, along with web-based production reporting and 24/7 real time monitoring of their pumping facility via VPN support.
Before investing in the new automated fill island, the Knoxville facility had experienced significant overtime expense. Says Parsons: “We were averaging more than 20 hr. of overtime per week, supplying seven branches with our array of gas mixtures. To more efficiently service our customers and to allow for future growth, we had to look at automation, a less labor-intensive process."
That’s exactly what the facility has done, courtesy of its 24-bay fill island with 12 traversing fill heads--a two fill head per valve package that helped to minimize cost. The island has 3 individual bank manifolds to achieve increased bank production. Once operators call up the appropriate program, the rest of the fill process is automated, including vent, vacuum, and remote cooling and starting of the high-pressure pump. “Our operators set the process in motion, and then are free to walk away to service another bay,” Parsons says. “To monitor the process, all they have to do is listen to what the island is telling them,” he adds, noting the various alerts and alarms that the equipment provides.
“Automation has enabled us to save labor, increase quality and consistency, and preserve raw materials.”
Robert Parsons, Holston Gases< inc. Operations Manager
Preserving Valuable Raw Materials
Mixtures are filled by weight using a reference cylinder and scale tied in with each pallet mixture head manifold. This is just one feature specified by Parsons after examining best practices at other distributorships.
“When we visited other distributors to look at their use of automated fill islands, we asked if they would do anything differently. One ‘wish’ we heard repeatedly was the desire to automate their processes using liquid scales. So, we decided to invest in the scales. Our liquid business is fairly large, and that’s a valuable raw material. You don’t want to lose product into the atmosphere. Now, once the process meets the preset weight, the liquid flow from the bulk tanks shuts off and an alarm sounds to tell the operator that the process has completed. We don’t have to keep an operator there the entire time.” noted Parsons.
A key technology enabler to the process is Weldcoa’s use of variable-frequency drives on all of the island’s pumps. This allows the pumps to slow down toward the end of the fill process, when approaching the target weight. Accuracy is to within a few grams. Holston and Weldcoa personnel can monitor the pumps and fill automation remotely using a PC, smartphone or tablet computer. Alarm conditions are instantly e-mailed out, and parameters can be changed remotely. “In the past, we would try to predict when we were close to having the liquid filled,” recalls Parsons. “The operator might walk away to perform another task, and the liquid could possibly overfill. Now, we have saving on two fronts—we don’t have to monitor as closely, saving labor; and we’re preventing overfills.”
Optimized Product Flow
Parsons also redesigned product flow, starting where the empty cylinders are sorted. “We bring in the empty cylinders at night, and the next morning we have three people on the sorting island ready to go. They don’t just sort—they do all of the prefill inspections, including sniff tests, inspecting for arc burns and checking test dates. We no longer require the fillers to do this.
At the fill island, Parsons offsets his filler-crew start times. Four operators staff the fill island--some come in at 7 a.m., others a 9 a.m. That enables him to run his fill island from 7 a.m. to 6 p.m., uninterrupted, every day. That strategic move, combined with the island’s automation equipment, has completely eliminated overtime at Holston.
A New Door Opens: Laser Gases
Last but not least, Parsons learned from the benchmarks of others of a better way to analyze gas-mix accuracy. Rather than having to roll cylinders from the fill bays to the lab for analysis, each fill location on the new island includes a sampling port, to send product directly to the lab. “Once the cylinder is filled," says Parsons, “and while it’s still on the pallet, we put the cylinder on the line and draw off some product for analysis.”
The Precision Specialty Gas Products (Weldcoa) analytical lab tests and qualifies industrial, medical and specialty-grades of pure gases and laser-gas mixtures. “Laser mixes,” says Parsons, “is one area where the fill island and analytical lab have really helped, even though it was not our original intent with the investment. The technology has opened up a lot of new doors for us in laser applications, due to the precision of the fill and test process.”
“It’s really changed the way we test,” Parsons continues, “now we can do all of the tests at once—percentage, moisture, oxygen content, hydrocarbons...all at one time with the flip of a switch. It’s resulted in a huge time savings. What used to take 35 minutes now takes just 5 minutes.”
Holston based their investment decisions on a rigorous, industry wide, survey in which they collected the best practices, from many different sources, in order to raise the bar and create a new standard of excellence.
To learn more about Holston Gases, Inc., we welcome you to visit www.holstongases.com