April 15, 2002
This article tells the story of a specialty chemical company and how it handles cylinder-gas challenges.
As fabricators strive to increase production and control costs, new efficiencies are welcomed on the shop floor. One small item that can help improve results is the gas cylinder that is chosen.
Rhodia Inc., a specialty-chemical company serving the automotive, health care, fragrance, apparel, electronics, personal care, and environmental protection industries, was using a large number of argon cylinders and VGLs (liquid cylinders) in its fabrication and repair facility in Baton Rouge, La., for repair work and new construction and in its welding shop. The company employs about 30 pipefitter welders at this location.
Changing out the cylinders was time-consuming. Rejects, impurities, and product loss of up to 10 percent from the liquid cylinders venting during nights and weekends were causing the company to lose money. These problems, along with lost cylinders and caps, led Rhodia to look for another cylinder handling method.
As its argon consumption increased, Rhodia's options were to try 16-packs, minibulk, or bulk cylinders. Using minibulk or bulk cylinders would have resulted in product loss caused by venting cryogenic tanks. High-pressure cylinders would require half as many changeouts as standard-pressure cylinders. After looking at the alternatives, the company became one of the first to use ARCAL™ 16-packs, a method of packaging welding gas blends devised by Air Liquide America Corporation, Houston. Rhodia's previous gas supplier offered standard-pressure argon cylinders.
Air Liquide America Corporation's 16-pack is a galvanized steel frame that holds 16 cylinders. The cylinders are all manifolded, with two residual pressure valves coming off the manifold, where a regulator is attached. An ARCAL cylinder holds almost twice as much gas as a standard industrial argon cylinder.
Rhodia uses on-site contractors to perform turnarounds and major repairs on the facility. These contractors work at the plant on a permanent basis, keeping the plant operating. According to Brian Davies, compressed gas account manager for Air Liquide America Corporation, this packaging method keeps product available for the plant and helps on-site contractors perform repairs and scheduled maintenance on the plant's equipment.
Rhodia piped its fabrication facility and now supplies all welding stations from a 16-pack of high-pressure (4,500-pounds-per-square-inch [PSI]) argon. Air Liquide America Corporation assisted the company by making recommendations on how the piping should be installed, and Rhodia used in-house welders and fitters to install the piping. The packs are attached to the piping system to eliminate handling of individual cylinders, which can expose personnel to safety hazards.
The individual cylinders are about 4 inches taller and 15 pounds heavier than typical cylinders, but the 16-packs are located outside the building and are loaded by a delivery truck-mounted forklift. Welders no longer have to find a cart, replace the empty cylinder, and move the regulator. As Rhodia expands its use of the 16-packs, safety can improve.
"The less exposure you have to potential safety hazards, the safer you will be," said Jeremy Barr, program manager for welding gases at Air Liquide America Corporation. "By reducing cylinder handling throughout Rhodia's facility by 50 percent, we expect they will see a 50 percent decrease on that hazard exposure."
When the high-pressure cylinders must be handled, a safety cap protects the valve and does not need to be removed during filling or transport. In addition to safety improvements, no caps are lost; the valve is protected during shipping, handling, and when in use; and less time is needed to remove and replace caps.
"We have few rejects and we save time by not having to frequently change bottles," said Jim Guidry, maintenance coordinator in Rhodia's Baton Rouge sulfuric acid plant.
A residual pressure valve ensures that the cylinder has never been contaminated, a cause of rejects. A positive pressure is on the cylinder at all times and an automatic shutoff that closes the valve if it is left open. It shuts the valve off when it reaches 25 PSI.
The gas supplier performs a traceable batch analysis in which one cylinder from every batch of 15 is analyzed and the results recorded. Every cylinder has a sticker on the cylinder wall near the Department of Transportation sticker indicating the batch number and date it was filled.
Helen Gallagher is owner of Computer Clarity and a free-lance writer based in Glenview, Ill. ARCAL is a registered trademark of the L'Air Liquide, S.A.
For more information, contact Rhodia Inc., 1275 Airline Hwy., Baton Rouge, LA 70805, phone 225-356-7111, fax 225-359-3762, Web site www.rhodia.com. Rhodia is a specialty-chemical company with five divisions worldwide, employing about 30,000 people.
Air Liquide America Corporation., 2700 Post Oak Blvd., Houston, TX 77056, phone 713-624-8774, fax 713-402-2053, e-mail jeremy.barr @airliquide.com, Web site www.airliquide.com.
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