GN3 OF3 MACHINE3 ELEMENTS
(First 3Revised 3Edition)
V.3B.3Bhandari3Fo
rmerly
Professor 3 &3 Head3of3 Mechanical3Engineering 3Vishw
akarma3 Institute3 of3 Technology,3 Pune.
McGraw-
Hill3Education 3(India)3Limited3 New3 Delhi
, 1
CHAPTER3 1
1.1 The3 series3 factor3 for3 R103 series3 is3 given3 by,
3103=1.2589
10
First3 number3 =3 1
Second3 number3 =3 13(1.2589)3=3 1.25893 =3 (1.25)
Third3number3=3(1.2589)(31.2589)3=3 (1.25893)323 =31.58483=3(1.6)
Fourth3 number3=3 (1.2589)2(1.2589)3=3 (1.25893) =31.99513 =3(2)
3
Fifth3 number3 =3 (1.2589)3(1.2589)3=3 (1.25893)343 =3 2.51173=3 (2.5)
Sixth3 number3 =3 (1.2589)4(1.2589)3=3 (1.25893)53 =3 3.16203 =3 (3.16)
Seventh3 number3=3 (1.2589)5(1.2589)3 =3 (1.25893)363 =33.98063 =3 (4)
Eighth3number3 =3(1.2589)6(1.2589)3=3 (1.25893)373 =35.01123 =3(5)
Ninth3 number3 =3 (1.2589)7(1.2589)3=3 (1.25893) =36.30863 =3(6.3)
8
Tenth3 number3 =3 (1.2589)8(1.2589)3 =3 (1.25893)93 =3 7.94183 =3 (8)
Eleventh3 number3=3 (1.2589)9(1.2589)3=3 (1.25893)1 =39.99803 =3(10)
0
In3 above3 calculations,3 the3 rounded3 numbers3 are3 shown3 in3 bracket.
1.2
The3 series3 factor3 for3 R203 series3 is3 given3 by,
3103=1.122
20
Since3every3third3term3of3 R203 series3 is3 selected,3the3 ratio3 factor3 (33)3is3 given3 by,
3 =3 (1.122)33 =31.4125
First3 number3=3200
Second3 number3 =3 2003(1.4125)3=3 282.53 =3 (280)
, 2
Third3 number3=3 200(1.4125)(3 1.4125)3 =3 2003(1.4125)23 =3 399.033 =3(400)
Fourth3 number3=3 200(1.4125)2(3 1.4125)3 =3 2003(1.4125)33 =3 563.633=3 (560)
Fifth3 number3 =3 200(1.4125)3(3 1.4125)3=3 2003(1.4125)43 =3 796.133 =3 (800)
Sixth3 number3 =3 200(1.4125)4(3 1.4125)3=3 2003(1.4125)53 =3 1124.533 =3(1120)
In3 above3 calculations,3 the3 rounded3 numbers3 are3 shown3 in3 bracket.3 The3 complete3 series3 is3
given3by,
200,3 280(282.5),3 400(399.03),3 560(563.63),3 800(796.13),3 1120(1124.53),3 …
1.3
Let3 us3 denote3 the3 ratio3 factor3 as3 (33).3 The3 derived3 series3 is3 based3 on3 geometric3 progression.
3The3power3rating3of3seven3models3will3as3follows,
(1)3403 ()03, (2)3 403 ()13, (3)3 403 ()23, 4)3403 ()33,
(5)3403()43, (6)3403()53, (7)3403()6
The3 maximum3 load3capacity3 is3 6303 kN.3 Therefore,
1/36
3 6303
403 ()63=3 630 or 3 = =31.5832
403
Load3capacity3 of3 first3 model3 =3 (40)3 kN
Load3capacity3of3 second3 model3 =3403(1.5832)3=363.333=3(63)3kN
Load3 capacity3 of3 third3 model3=3 403(1.5832)23=3 100.263 =3 (100)3 kN
Load3 capacity3 of3 fourth3model3 =3 403(1.5832)33=3 158.733=3 (160)3 kN
Load3 capacity3 of3 fifth3 model3=3 403(1.5832)43=3 251.313 =3 (250)3 kN
Load3 capacity3 of3 sixth3 model3=3 403(1.5832)53=3 397.873=3 (400)3 kN
Load3 capacity3 of3 seventh3 model3=3 403(1.5832)63=3 629.903=3 (630)3 kN
1.4
Let3 us3 denote3 the3 ratio3 factor3 as3 (33).3 The3 derived3 series3 is3 based3 on3 geometric3 progression.
3The3speeds3of3different3steps3will3as3follows,
, 3
(1)3723 ()03, (2)3 723 ()13, (3)3 72()23, (4)3723 ()33,
(5)3723()43, (6)3723()53, (7)3723()6 (8)3 723()7
(9) 723()8 (10) 723()9 (11) 723()10
The3 maximum3 speed3 is3 7203 r.p.m.3 Therefore,
1 3/310
3 7203
723 ()103=3 720 or 3 = =3 (10)1/103 =103103 =31.2589
723
Speed3 of3 first3 step3 =3723r.p.m.
Speed3of3 second3 step3=3723(1.2589)3=3 90.643 =3(91)3 r.p.m.
Speed3 of3 third3 step3=3 723(1.2589)23=3 114.113 =3 (114)3 r.p.m.
Speed3 of3 fourth3 step3 =3 723(1.2589)33=3 143.653=3 (144)3 r.p.m.
Speed3 of3 fifth3 step3=3 723(1.2589)43=3 180.843 =3 (181)3 r.p.m.
Speed3 of3 sixth3 step3 =3 723(1.2589)53=3 227.663=3 (228)3 r.p.m.
Speed3 of3 seventh3 step3 =3 723(1.2589)63=3 286.603=3 (287)3 r.p.m.
Speed3of3 eighth3 step3 =3 723(1.2589)73=3 360.803=3 (361)3 r.p.m.
Speed3of3 ninth3 step3=3 723(1.2589)83=3 454.223=3 (454)3 r.p.m.
Speed3 of3tenth3 step3 =3723(1.2589)93=3 571.813 =3 (572)3 r.p.m.
Speed3of3eleventh3 step3 =3 723(1.2589)103=3 719.853=3 (720)3 r.p.m.