There are several advantages to be taken into account during the analysis of the payback time related to the acquisition of new gas mixing equipment. Many are directly correlated to the existing gas mixing equipment used.
Reduced cost :
Gas mixtures are often purchased in pre-mixed cylinders; gas distributor then passes the blending costs to the user. Pre-mix gas pricing is often based on the price of the most expensive gas in the mix bringing the lower cost gas at the high price. For example, in a mixture of SF6 and CO2, the price of lower cost CO2 can equal the SF6 higher price.
In cases where a diecaster buys pure gases and does its own mixture, the concentrations are sometimes based on a fixed-orifice calculation sizing producing only one non adjustable concentration. In real life, the mixture concentration can be optimized with an adjustable gas mixer and large quantities of expensive gases can be saved. The quantity of SF6 has been considerably reduced in many diecasting plants after optimization of mixture concentration with an adjustable gas mixer.
Optimized process:
Fixed-orifice and volumetric mixers are very sensitive to process variations. Based on massic-measurement technology, gas mixers are insensitive to gas density, pressure and temperature variations. This " fit-and-forget " technology provides accuracy, repeatability and immunity against process interferences. Gas mixers using massic technology provide a precision ten times superior and a greater flow turndown than all fixed-orifice gas mixers.
Optimized mixture:
With pre-mixed cylinders, gases may separate or even stratify when using fixed-orifice and volumetric mixers equipped with a surge tank. This may considerably alter the quality of your product. On-line gas mixers will eliminate that problem by ensuring constant correct mixture.
Plant installations for harsh gases:
Many processes require the use of harsh gases. For example, a process may require a mix of SO2 and other gases. Instead of running pure SO2 throughout the plant to the point of mix, it is safer and cost-effective to mix gases in an enclosed plant-wide gas mixer with cylinder(s), and then run a less toxic, less corrosive and phase change sensitive mixed gas through standard piping.
Ease of operation and maintenance procedures:
A process demanding frequent flow, pressure or gas concentration adjustments, such as laser applications and shield gas, will be more effective if the gas mixing is automated. Usage of only flow controllers, valves or pressure regulators to obtain the proper gas mix is subject to large unwanted variations and increases manual handling.
Higher quality products:
The use of only flow controllers, valves or pressure regulators in a process demanding frequent flow, pressure or mixture adjustments, may cause serious quality issues if all variables are not regulated properly.
Reduced handling time:
Changing cylinders, with their flow meters and regulators, can be fastidious when you need to change your mix or even your gases. You will reduce setup time by using proper adjustable equipment with automatic bottle changeover.
Allowing training and better supervision in welding applications:
Gas mixers are ideal for training in welding applications because you can see the effect of different shielded gas mixtures on weld quality, the product appearance and other properties.
Avoids fines and penalties
New gas mixing techniques allow the reduction of GWP and greenhouse gas emissions by u sing new alternative cover gases and reducing the use of ozone depleting chemicals. Gas mixers offer convenient data collection software to ease your environmental reporting task. |
