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Nitrogen Tire Inflation Membrane vs. PSA. Parker Hannifin PSA. We make PSA units in Baltimore Typically for high flow, high purity applications Do not believe it meshes w/ auto market due to increased attention required. PSA System Operation. The Case for PSA . Touted as new technology
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Parker Hannifin PSA • We make PSA units in Baltimore • Typically for high flow, high purity applications • Do not believe it meshes w/ auto market due to increased attention required
The Case for PSA • Touted as new technology • NOTE: It is an old technology that is well known outside Autos • Price per scfm • Fuzzy math on the flow rate • Lower price, lower quality from China • NOTE: Nearly equivalent price, or higher in USA • Air Factor • Much better at higher purities • NOTE: Relatively close at lower purities • Dewpoint • Will approach -70F vs. -40F for membranes vs. +45F for dry air • NOTE: 11ppm vs. 79 ppm vs. 6500 ppm @ atmosphere • Purity • 99.99% is possible, usually touted at 99% • NOTE: Need about 97%+ in the tank to get 95% in the tire
PSA Facts – Carbon Molecular Sieve • CMS • Adsorbs oxygen under high pressure, desorbs at atmosperic pressure • Controlled by valve cycling • High grade CMS vs. low grade CMS • Has a finite life significantly hampered by contamination • Water or oil or oil vapor
PSA Facts – Contamination • CMS behaves just like a carbon filter • Releases adsorbed oxygen and water vapor • Oil, water and hydrocarbon vapor attach, plug up the pores and compromise life and performance.
PSA Facts – Proprietary Fill Technique • Ensures long term performance • Eliminates ratholing, channeling, dusting, etc. • Hampers long term performance & life of unit • Buffer differential pressure • Fluidization • Carbon integrity • Vessel Sizing • Gas velocity
PSA Facts - Portability • If towers are not packed properly, carbon will shift as moved • As carbon shifts, ratholing, channeling and dusting will occur • Units life & performance is compromised • Very heavy and difficult to move around, especially on casters
PSA Facts – Maintenance • Membrane: passive vs. PSA: active • Membrane is more trouble free • Solenoid Valves • Frequent cycling - wear • Maintenance team • Stock replacements • Controllers • Valve timing
PSA Facts - Pressure • No benefit from higher pressure found in most auto shops • One mfg advertises 8 scfm equivalent membrane flow. • True flow is 6 scfm • At what purity? • 40% drop 95% - 98% • Say flow in equivalent membrane is 8 scfm
PSA Fill Times – No Tank • N2 fill cycle: 8 mins • Purge time: 6 mins • Fill time: 2 mins • Without tank, no N2 produced during long purge cycle • Compare membrane vs. PSA in 10 cf tire (40 cf tot) • 5.1 scfm membrane w/ tank: • Makes N2 during purge • Cycle = 40/5.1 = 7.84 mins • 6 scfm psa, no tank • No N2 during purge • 7 mins fill time • Cycle: 7 mins + 6 mins = 13 mins
Built in China Quality? Issues? For sale? Ownership? Membrane & steel price increase What’s best for customer? Deceptive flow Deceptive price What is true price? Long term focus? Serviceability is now their responsibility Reports of other Chinese PSA providing 81% N2 Tank often an option Membranes for stationary units Couldn’t compete w/ portable PSA for Tire Inflation
Take a Look Inside • This is a picture of a PSA unit designed for tire inflation • Compare w/ membrane • Too many chances for critical failures • Not making money when nitrogen is down • Is this, coupled with all of the other factors, truly worth the savings?