Gas Filling achieves new highs for productivity and filling accuracy

For over 10 years Tungum Ltd has been the UK agent for CPV Manufacturing of Philadelphia, USA, promoting and selling their unique range of leading edge valves and fittings. More recently Tewkesbury-based Tungum has been awarded the opportunity represent CPV in France, Holland, Belgium and Luxemburg.

What follows is a case study of a recent installation carried out at Norco, Idaho.

At the Norco, Inc. gas filling plant located in Boise, gas filling has taken on a whole new meaning. This 53,000 sq. ft. automated facility employing nearly 50 people has been in operation now for about three and a half years. Built as a new facility in late 2008, the plant houses an automated gas fill system by Weldcoa, Inc., of Aurora, IL and a 1,250 sq. ft. research lab for Norco’s specialty gases line NorLab.

According to Ken Goicoechea, Boise Plant Manager, "Norco, Inc. is the largest independently owned Welding, Safety, Medical, and Industrial gas supplier in the United States, with over 50 branch offices in 7 western states."

The plant has been designed using hundreds of CPV Manufacturing, Inc. FloMasterTM Air-Operated Valves and CPV O-Seal Valves and fittings.

This plant fills cylinders with many different types of high pressure gases. CPV valves and fittings were specified due to their proven leak-proof performance and rock-solid operating reliability. "The valves," according to Weldcoa's Chief Engineer, Carl Schmidt, "were specified in the needle valve configuration because with high pressure gases, 3000 psi and above, valves need to be opened slowly in a controlled manner.”

A hybrid design improves plant productivity
Inside the Boise fill plant are two double-sided palletized fill islands designed, built, and installed by Weldcoa. The islands have 13 fill heads capable of handling as many as 8-10 cylinder pallets at one time depending on product needs. What makes this plant different is that one half of the fill islands are fully automated and the other half is manually operated. Medical grade gases like oxygen, air, and nitrogen at pressures up to 4500 psi are filled manually while large volume welding gas mixtures and pure industrial gases such as nitrogen, helium, industrial oxygen and argon are more efficiently filled automatically.

According to Goicoechea, "The entire plant is really a unique hybrid system."

Gases from the plant's main cryogenic tanks are pumped into cylinders directly and also transferred and pressurized continuously during the day into separate exterior ground storage tanks. This state of the art system was primarily designed to eliminate waiting for product availability throughout different fill areas in the plant. The Boise plant also does a lot of helium filling for use by labs and welding operations. To keep up with the volume, helium from tube trailers is transferred and pressurized to 3000 psi during the night when the plant is closed, and controlled by an automated Compressor Control Panel.

"FloMaster valves inside the plant, on the fill island, plus the FloMaster valves outside the plant on the ground storage tanks which are subjected to extreme Idaho winter weather conditions have all performed flawlessly since installation. We have many facilities using FloMaster valves that have hardly had any maintenance which have been operating for seven or eight years without problems.” says Goicoechea.

Precise accuracy of the fill assured Weldcoa's Sur-Fill automated software with its many PLCs assure gas mixtures are controlled, monitored, and safely filled to preset cylinder weights which are calibrated very precisely to within grams of their final assigned weight when compared to a Norco reference cylinder. The program also controls and monitors pure gases just as precisely, so they are filled to their preprogramed cylinder pressures in accordance to type of gas being filled.

Published: 16th September 2012