friction clutches - Arten Freios e Embreagens Industriais

Table of Contents◗APPLICATION ENGINEERING DATA“Air Champ” ®◗ RESPONSE TIME DATAAll data obtained by using 8inch long 1/4 inch diameterhose, 1/8 inch NPT fittingsand quick exhaust valves.t v = Valve delay timetv = 5 msec for .062,3 way valvetv = 8 msec for 4 wayvalve, pilot operatedtv = 70 msec for 4 wayvalve, spring operatedt 1 = Time from start ofvalve open to start oftorque riset 290 = Time from start oftorque rise to 90%value of torquet 2100 = Time from start oftorque rise to 100%value or torquet 3 = Time from start ofvalve exhaust to startof torque decayt 410 = Time from start oftorque decay to 10%valve of torquet 40 = Time from start oftorque decay to 0%value of torque◗ TORQUE RISE RESPONSE% Value of Torque366Time (msec)◗ TORQUE DECAY RESPONSE% Value of TorqueTime (msec)For Clutches and Brakes using “Air Champ®” ValvesC R -Pressure FactorObtain CR values for units from table page 365 and366. Read times at 100 PSIG directly from CR vsResponse Time graphs below◗ 3-WAY VALVE RESPONSE TIMESC R -Pressure Factor1.0.5.2.1.05.03.02Response Time (msec)◗ 4-WAY VALVE RESPONSE TIMES1.0.5.2.1.05.03.02t 3t 2100t110 0t 4t 4t190t 2 10t 4010 20 30 50 100 200 500 1000Response Time (msec)t 290t 3t 2100010 20 30 50 100 200 500 1000t 40Correction factor for operating pressures lessthan 100 PSIG Use formula t p = C p (t) 100◗ 3-WAY CORRECTION FACTOR GRAPHC P -Pressure FactorOperating Pressure (psig)◗ 4-WAY CORRECTION FACTOR GRAPHC P -Pressure Factort p = Response time at pressure PC p = Response pressure factor atpressure P from graph.t 100 = Response time at 100 PSIGCorrection factor for hose lengths greater than 8inches (1-10 FT) Multiply all response times by C Lwhere C L = t 1 + .7 (L - .66)t 1 Found below at operating pressureL Length of hose in feet4.02.01.51.0.8.6.4.24.02.01.51.0.8.6.4.2t 110 20 30 40 50 60 70 80 90 100Operating Pressure (psig)EXAMPLE: Determine the various response times defined for a 625 Modular Brake operating at75 PSIG using a Nexen 4-way valve.SOLUTION: I. Determine the response times at 100 PSIG.1.) Obtain the response factor, C R , from the Clutch andBrake Data Table page 365 and 366 C R = .096.2.) Read the response times at 100 PSIG directly off the 4-wayC R vs. Response Time graph; t 1 = 14 msec, t 290 = 27 msec,t 3 = 14 msec, t 410 = 34 msec, t40 = 46 msec.II. Correct the response times for 75 PSIG.1.) Obtain the C p factor from the 4-way Correction Factor Graph.2.) Calculate the corrected response times using the formula (t) 75 = C P (t) 100 .i.e. (t 1 ) 75 = (1.25) (14 msec) = 17.5 msec(t 290) 75 = (1.08) (27 msec) = 29.2 mseclikewise the following are obtained: (t 2100) 75 = 46 msec, (t 3 ) 75 = 13.3 msec(t 410) 75 = 24 msec, (t 40) 75 = 36.8 msect1100t 290t 2t 3t 40t 410t1t 2100t 290t 3t 40t 41010 20 30 40 50 60 70 80 90 100