MAC Advantage Brochure
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•MINIMAL FRICTION

HOW MAC'S PERFORMANCE ADVANTAGES HELP MAKE YOUR EQUIPMENT MORE RELIABLE - FASTER - MORE REPEATABLE. TLD/PLD The TLD function (Traveling Lab Demonstration) measures critical valve performance characteristics • Shifting forces, Response Time, Speed, Repeatability and Flow. The PLD function (Proportional Lab Demonstration) measures critical proportional regulation characteristics ■ Response Time, Accuracy, Hysterisis, Repeatability and Flow.

High SHIFTING FORCE (Energized) - SHORT STROKE- SHIFTING FORCES unaffected by changing air pressure (IN/EXH) SHIFTING FORCES virtually unaffected by typically contaminated air Low friction minimizes resistance to SHIFTING FORCES High SHIFTING FORCE (De-energized) - STRONG RETURN SPRING - Consult out monuol lot the use, instollotion ond mointenonte ol out Hot Volves (see genetol catalog).

(A) SOLENOID DE-ENERGIZED(B) SOLENOID ENERGIZED Sequence of events (A) • Solenoid is de-energized (B) - Solenoid is energized - Armature is attracted magnetically downwards, extending push pin which shifts poppet from upper to lower seat. - Movable pole piece is ottrocted magnetically upwards to meet the armature which compensates for difference between solenoid stroke and shorter valve stroke. Armature and pole piece therefore close regardless of valve position. • Short stroke solenoid produces high energization shifting force. • High force return spring due to high force solenoid,...

«= OVAL SHAPE ARMATURE Oval shape armature = Increased coil winding Oval shape armature = Increased coil iron volume Oval shape armature = Higher shifting forces Round armature = Less coil winding Round armature = Less coil iron volume Round armature = Lower shifting forces

typical UNBALANCED poppet 3-way air valve SKINNER TYPE ASCO TYPE Armature poppet seal Weak return spring UNBALANCED POPPET = INCONSISTENT LOW SHIFTING FORCES • Spring force (holding poppet on seat) is constant. • Inlet oir pressure acts upon a single sealing area. • Inlet pressure X sealing area creotes a force that opposes return spring shifting force. • Force created by inlet air pressure on inlet poppet seal varies as inlet air pressure varies. • Changing inlet pressures therefore affect energizing and de-energizing shifting forces. • Normal pressure fluctuations cause inconsistent...

BALANCED POPPET = CONSISTENT HIGH SHIFTING FORCES Exhaust Contaminants Isolated From Solenoid Parts = Clean Solenoid • Sealing areas ore equal • End seals balance poppet seals • Forces created by air pressure are equal in both directions • Changing pressure therefore has no effect on shifting forces • Valve shifting forces are consistent and independent of pressure fluctuations • High solenoid ond return spring forces ensure high speed and precise repeatability • Exhaust contaminants are isolated from the solenoid • Manual override - standard • Constant high flow maintained throughout the...

SMALL DIRECT SOLENOID POPPET VALVE |k ADVANTAGES • 4 balanced poppets on a one-piece valve stem • End poppets seal first on conicol seats ond cushion inlet poppet, eliminating cutting • Exhaust seals are not under inlet pressure thus reducing friction • Integral non-rising flow controls available • Short stroking balanced poppet allows for direct solenoid operation with high shifting forces, minimized friction, fast response and high flow in a small package

DIRECT OPERATED ADVANTAGE: No minimum operating pressure. ^et Energized DISADVANTAGE: Force Sticking due to low shifting forces F in both directions on long stroke valves. ADVANTAGE: High shifting force in one direction. DISADVANTAGE: Sticking due to low return shifting forte. Must be able to operate at low pressure. Therefore, return spring force is low. 3-WAY PILOT OPERATED (Air and ADVANTAGE: High shifting forces in both directions. DISADVANTAGE: Resistance to energizing shifting forces from air/spring return. ADVANTAGE: Highest shifting forces in both directions. No resistance...

Small direct 3-way solenoid operated valve SPRING ■ VALVE I SOLENOID t SHIFTING FORCES unaffected by changing air pressure (IN/EXH) HIGH SHIFTING FORCE SHIFTING FORCES virtually unaffected (De-energized) by typically contaminated air Low friction minimizes resistance to SHIFTING FORCES I AIR/SPRING ■ VALVE Solenoid pilot operated large valve I Valves that don't stick 10

Small direct 4-way solenoid operated valveSPRING VALVE SOLENOID SHIFTIHG FORCES unaffected by changing air pressure (IN/EXH) ■ nTTB HIGH SHIFTIHG FORCE (De-energized) SHIFTING FORCES virtually unaffected by typically contaminated air HIGH SHIFTIHG FORCE (Energized) Low friction minimizes resistance to SHIFTIHG FORCES

SPOOL & BORE ADVANTAGES SPOOL PLUS BORE = WIPING ACTION = VALVES THAT DON'T STICK MAXIMIZES ABILITY TO OPERATE UNDER CONTAMINATED CONDITIONS, WHILE MINIMIZING FRICTION • Large minimum piston area (3 cm') provides high shifting force even at minimum operating pressure • Air/Spring assures maximum return shifting force • Precision ground bonded spool controls compression - wipes contaminants away with minimum friction • Chemically hardened seals eliminate creep, reduce friction and increase life • Lubricant in rubber reduces friction - enhances nonlube service • Two seals each controlling a...

TYPICAL PILOT OPERATED 10 MM DESIGN MAC 44 SERIES DIRECT OPERATED 10 MM DESIGN • "U cup" plus 4 "0-rings" in the bore ot any one time - high friction • 0.5 watt limited volume magnet wire plus small core iron size • low shifting force • Unbalanced 3 way pilot - low shifting forces compromised by fluctuations in air pressure • Small piston area - low shifting force • Small orifice "0.0004 in'" (0,26 mm') - prone to doging • Air return only ■ insufficient shifting force at low pressure to permit mechanicol spring • Many parts-complicated design • Long stroke spool, unbonded seals can...