SKF Roller Screws.pdf - E. Fox (Engineers)

Lead precision according to ISOLead precision is measured at 20°C on the useful stroke l u , which is the threaded length decreased, at each end, bythe length l e equal to the screw shaft diameter.G1 G3 G5V 300p, µm 6 12 23l u e p v up e p v up e p v upmm µm0 - 315 6 6 12 12 23 23(315) - 400 7 6 13 12 25 25(400) - 500 8 7 15 13 27 26(500) - 630 9 7 16 14 32 29(630) - 800 10 8 18 16 36 31(800) - 1000 11 9 21 17 40 34(1000) - 1250 13 10 24 19 47 39(1250) - 1600 15 11 29 22 55 44(1600) - 2000 35 25 65 51(2000) - 2500 41 29 78 59(2500) - 3150 96 69(3150) - 4000 115 82l eMean travel :the line which fitsthe curve best bymethod of leastsquares.v300aThreaded length300 mml uµm+l emml 0v up+ v ua-l mv 300pl u =l e =l o =l s =c =e p =useful travelexcess travel (no lead precision required)nominal travelspecified traveltravel compensation (difference between l s andl o to be defined by the customer, for instanceto compensate an expansion)tolerance over the specified travelV = travel variation (or permissible band width)V 300p = maximum permitted travel variation over 300 mmV up = maximum permitted travel variation over theuseful travel l uV 300a = measured travel variation over 300 mmV ua = measured travel variation over the useful travelCase with value of c specified by thecustomer.Case with c = 0 = standard version whenno value given by the customer.leThreaded lengthl uµm+l eThreaded lengthµm+mml 0l el ul ee p v upe pcl mv upe pl 0mme p-l s-15