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Volume 7   Issue 3               March 2006

Winning at Losing
Stop Being a Gas-Fill Loser 

by Tom Gallagher

There is an art to losing. It takes a special person of unusually bad habits to achieve the highest ranks in this art. Sad to say, the older I get, the closer these loftier ranks become. First it was my head that started to grow a “sunroof,” and I definitely did not like the loss of hair. Then it was my teeth but I have a good dentist so no one will ever know. I still do not like losing anything but now I must accept it and/or try to find ways to avoid it. Losing is only good for debt, weight and corrupt politicians. 

Now what does losing have to do with windows?

Have you ever walked through a window factory and seen a clean floor? Usually there is debris of some sort from vinyl scraps to broken glass to discarded aluminum pieces. When I see this I see dollar signs and wasted money. There may never be a window factory that uses 100 percent of every piece of material that it purchases with zero waste, but every door and window manufacturer must strive daily to reduce expensive material shrinkage. If not then they are accomplishing the art of losing through complacency. This is called complacency losing. 

This is also true of the inert gas used to fill insulating glass units (IGUs). If an IGU manufacturer puts argon or krypton in its door or window via a hand-filled system then, on average, there is approximately 30- to 40-percent gas waste per window. Only 60-70 percent of the gas will end up in any IGU. I hate this! I see dollar signs being sent into the air. Now there are many good reasons for this waste of gas starting with “speeding up” the filling time per window to reduce labor. However this only causes turbulent flow within the IGU and sends more expensive gas into the atmosphere (see graphic page 29). It is very important to always follow the recommended gas-filling procedures provided by the equipment manufacturer. Trying to “speed up” IGU manufacturing by reducing the gas fill time causes a greater loss of gas then needed and therefore decreases productivity. This is called “shooting yourself in the foot losing” and it hurts.

IGU Gas Volume Formula

The formula to determine the amount of gas, at one atmosphere, in each IGU is:

Length x width x inner diameter x 0.01639 = number of liters of gas at one atmosphere in each IGU.

Lets take a sample IGU with the dimensions of:

• Height: 24 inches 
• Width: 24 inches 
• Inner Dimension: 0.5 inches

Multiply 24 x 24 x 0.5 = 288 cubic inches.

Then multiply 288 cubic inches by 0.01639 liters per cubic inch to obtain 4.72 liters of gas at one atmosphere (14.7 psig) in this size IGU.

In this sample size IGU, approximately two liters will be wasted during the normal filling process and sent back into the atmosphere. By “speeding up” production this could increase to 4 to 5 liters due to turbulent flow. Each IGU manufacturer should strive for laminar flow during the IGU gas filling process to increase productivity.

Check and Balance Gas Audit

IG manufacturers having a hand-held gas filling system or automatic IG gas filling processing equipment should perform a weekly or monthly check and balance audit of how many cubic feet of IGU gas chamber space they produce versus the quantity of gas purchased. This would show the percentage of productivity achieved with gas filling. 

The most critical aspect of IGU gas filling is the person doing the filling. If this individual forgets to close the gas cylinder valve when he goes home at night, there is the possibility of gas leakage through a loose connection. Always close the gas cylinder off at the cylinder valve. Do not use the gas regulators as a replacement for a cylinder valve. Gas regulators were never designed as cylinder valves. This could be called “big time losing.” I often get telephone calls on Monday mornings asking me to rush out a cylinder of gas because of a “slight” oversight in the plant. 

The IGU gas filler also must always take proper care of the gas-filling equipment. Too many times I have seen sensitive gas filling nozzles thrown on the floor and stepped on, causing unnecessary damage. In addition I have often heard the lunch bell ring and seen the person doing the gas filling leave a partially gas-filled IGU to go on break. Of course the gas escapes from the window when this happens. Pride in work equates to a quality product!

Gas Recovery Systems

New technology is now here to help larger IGU manufacturers from losing expensive krypton gas. Gas recovery systems used in the lighting and detector industries for decades have reached the fenestration industry in the form of the R-20 Krypton Gas Recovery System. (The R-20 is exclusively made by Advanced Photonics Inc. for our company.)

The R-20 is designed to interface with fill/ purge hand-held gas filling systems gas, and helps IG manufacturers to improve gas utilization efficiency through recycling. 

A 15 to 20 percent annual krypton gas recovery rate can be achieved by following proper recovery procedures. This is called “winning” not “losing.”
There are many ways to lose in an IG manufacturing facility. You can lose material through complacency and this will lead to losing at the bottom line which leads to losing your patience. All this losing is not good. One can grow a “sunroof” overnight!

Seek ways to avoid losses. What was done in the past and overlooked because of inexpensive material costs should be reviewed on a regular basis to achieve maximum profit returns. 

Tom Gallagher is vice president of Spectra Gases in Branchburg, N.J.

© Copyright 2006 Key Communications Inc. All rights reserved. No reproduction of any type without expressed written permission.