Machine Design Databook Episode 2 part 5 docx

Max diam, head, of slot, of slot, head diam, head, of slot, of slot, Note: Radius of fillet at base of truss- and pan-head machine screws shall not exceed one-half the pitch of the screw

TABLE 18-35

Machine screw heads—pan, hexagon, truss, and 1008 Flat heads

Max diam, head, of slot, of slot, head diam, head, of slot, of slot,

TABLE 18-35

Machine screw heads—pan, hexagon, truss, and 1008 Flat heads (Cont.)

Max diam, head, of slot, of slot, head diam, head, of slot, of slot,

Note: Radius of fillet at base of truss- and pan-head machine screws shall not exceed one-half the pitch of the screw thread

Hexagon-head machine screws are usually not slotted; the slot is optional Also optional is an upset-head type for hexagon-head machine screws of

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TABLE 18-36

Machine-screw heads—binding head

Max diam, of head, of slot, of slot, of oval, undercut,a undercut,

Use of undercut is optional

Note: Binding-head machine screws may be furnished with cross-recessed heads

TABLE 18-37

Slotted-head cap screws28

Nominal

diam, slot diam, head, of head, slot, diam, head slot, diam, head, slot,

TABLE 18-38

Socket-head cap screws

TABLE 18-39

Square-head set screws28

flats corners Height of head neck relief head relief relief

16 0.3125 0.3125 0.302 0.415 15 0.245 0.224 0.240 0.225 25 0.036 0.111

3 0.3750 0.375 0.362 0.497 7

32 0.293 0.270 0.294 0.279 15 0.041 0.1257

TABLE 18-40

Square-head setscrew points28

Full-dog, half-dog, andpivot pointaOval

Pivot points are similar to full-dog point except that the point is rounded by a radius equal to J

Where usable length of thread is less than the nominal diameter, half-dog point shall be used

When length equals nominal diameter or less, Y ¼ 1188 28; when length exceeds nominal diameter, Y ¼ 908 28

Note: All dimensions are given in inches

TABLE 18-41

Slotted headless setscrews28

Radius of Width Depth Oval- Diam of cup and Diam of Length ofNominal headless of of points flat pointsC dog pointP dog pointa

16 0.3125 0.313 0.051 0.078 0.234 0.172 0.156 0.203 0.195 0.156 0.078

3 0.375 0.375 0.064 0.094 0.281 0.212 0.194 0.250 0.241 0.188 0.0947

16 0.4375 0.438 0.072 0.109 0.328 0.252 0.232 0.297 0.287 0.219 0.109

1 0.500 0.500 0.081 0.125 0.375 0.291 0.270 0.344 0.344 0.250 0.1359

16 0.5625 0.563 0.091 0.141 0.422 0.332 0.309 0.391 0.379 0.281 0.140

5 0.625 0.625 0.102 0.156 0.469 0.371 0.347 0.469 0.456 0.313 0.156

3 0.750 0.750 0.129 0.188 0.563 0.450 0.425 0.563 0.549 0.375 0.188

a

Where usable length thread is less than the nominal diameter, half-dog point shall be used

When L (length of screw) equals nominal diameter or less, Y ¼ 1188 28; when L exceeds nominal diameter, Y ¼ 908 28

TABLE 18-43

American National Standard metric hex cap screws (ANSI B18.2.3.1M-1979, R1989)

Width across Width across Head Wrenching Washer

All dimensions are in millimeters

furnished

purposes

For additional manufacturing and acceptance specifications, reference should be made to Standard

Courtesy: American National Standards Institution, New York, USA (ANSI B18.2.1M-1979, R1989)

TABLE 18-44

American National Standard metric formed hex screws (ANSI B18.2.3.2M-1979, R1989)

screw Body diam, flats, corners, height, height, face thickness, face diam,

All dimensions are in millimeters

Basic thread lengths, B are the same as given in Table 18-47

For additional manufacturing and acceptance specifications, reference should be made to the Standard

Courtesy: American National Standards Institution, New York, USA (ANSI B18.2.3.2M-1979, R1989)

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TABLE 18-45

American National Standard metric heavy hex screws (ANSI B18.2.3.3M-1979, R1989)

screw Body diam, flats, corners, height, height, face thickness, face diam,

and thread

M12 1:75 12.00 11.73 21.00 20.67 24.25 23.35 7.76 7.24 5.2 0.6 0.3 19.0M14 2 14.00 13.73 24.00 23.67 27.71 26.75 9.09 8.51 6.2 0.6 0.3 22.0M16 2 16.00 15.73 27.00 26.67 31.18 30.14 10.32 9.68 7.0 0.8 0.4 25.0M20 2:5 20.00 19.67 34.00 33.00 39.26 37.29 12.88 12.12 8.8 0.8 0.4 31.0M24 3 24.00 23.67 41.00 40.00 47.34 45.20 15.44 14.56 10.5 0.8 0.4 38.0M30 3:5 30.00 29.67 50.00 49.00 57.74 55.37 19.48 17.92 13.1 0.8 0.4 46.0M36 4 36.00 35.61 60.00 58.80 69.28 66.44 23.38 21.72 15.8 0.8 0.4 55.0

All dimensions are in millimeters

Basic thread lengths, B, are the same as given in Table 18-47

Transition thread length, X, includes the length of incomplete threads and tolerances on the grip gaging length and body length It is intended forcalculation purposes

For additional manufacturing and acceptance specifications, reference should be made to the Standard

TABLE 18-46

American National Standard metric hex flange screws (ANSI/ASME B18.2.3.4M-1984)

Nominal

All dimensions are in millimeters

Basic thread lengths, B, are the same as given in Table 18-47

Transition thread length, X, includes the length of incomplete threads and tolerances on grip gaging length and body length

This dimension is intended for calculation purposes only

For additional manufacturing and acceptance specifications, reference should be made to the Standard

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Lengths in parentheses are not recommended Recommended lengths of formed Hex Screws, Hex Flange Screws and Heavy Hex Flange Screws

do not extend above 150 mm Recommended lengths of Heavy Hex Screws do not extend below 20 mm Standard sizes for government use

b

Does not apply to Hex Flange Screws and Heavy Hex Flange Screws

For available diameters of each type of screw, see respective dimensional table

TABLE 18-48

American National Standard Metric Hex Bolts (ANSI B18.2.3.5M-1979, R1989)

All dimensions are in millimeters

a

This size with width across flats of 15 mm is not standard Unless specifically ordered, M10 set bolts with 16 mmm width across flats will befurnished

b

Basic thread length, B, is a reference dimension

For additional manufacturing and acceptance specifications, reference should be made to the Standard

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TABLE 18-49

American National Standard Heavy Hex Bolts (ANSI B18.2.3.6M-1979, R1989)

Nominal Body diam, Width across flats, Width across corners, Head height, Wrenching

All dimensions are in millimeters

For additional manufacturing and acceptance specifications, reference should be made to the Standard

TABLE 18-50

Recommended clearance holes for metric hex screws and boltsa

Nominal Clearance hole diam, basic,Dh Nominal Clearance hole diam, basic,Dh

thread pitch Close Normal, preferred Loose thread pitch Close Normal, preferred Loose

All dimensions are in millimeters

Normal Clearance: This is preferred for general purpose applications and should be specified unless special design considerations dictate the needfor either a close or loose clearance hole

Close Clearance: This should be specified only where conditions such as critical alignment of assembled parts, wall thickness or other limitationsnecessitate use of a minimum hole When close clearance holes are specified, special provision (e.g countersinking) must be made at the screw usedbolt entry side to permit proper seating of the screw or bolt head

Loose Clearance: This should be specified only for applications where maximum adjustment capability between components being assembled isnecessary

Recommended Tolerances: The clearance hole diameters given in this table are minimum Recommended tolerances are: for screw or bolt diameter

þ0:6 mm

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TABLE 18-51

American National Standard metric hex screws and bolts—reduced body diameters

Metric Formed Hex Screws (ANSI B18.2.3.2M-1979, R1989)M5 0:8 5.00 4.82 4.46 4.36 3.5 2.5 M14 2 14.00 13.73 12.77 12.50 8.0 7.0M6 1 6.00 5.82 5.39 5.21 4.0 3.0 M16 2 16.00 15.73 14.77 14.50 9.0 8.0M8 1:25 8.00 7.78 7.26 5.04 5.0 4.0 M20 2:5 20.00 19.67 18.49 18.16 11.0 10.0M10 1:5 10.00 9.78 9.08 8.86 6.0 5.0 M24 3 24.00 23.67 22.13 21.80 13.0 12.0

Metric Hex Flange Screws (ANSI B18.2.3.4M-1984)M5 0:8 5.00 4.82 4.46 4.36 3.5 2.5 M12 1:75 12.00 11.73 10.95 10.68 7.0 6.0M6 1 6.00 5.82 5.39 5.21 4.0 3.0 M14 2 14.00 13.73 12.77 12.50 8.0 7.0M8 1:25 8.00 7.78 7.26 7.04 5.0 4.0 M16 2 16.00 15.73 14.77 14.50 9.0 8.0

Metric Hex Bolts (ANSI B18.2.3.5M-1979, R1989)M5 0:8 5.48 4.52 4.46 4.36 3.5 2.5 M14 2 14.70 13.30 12.77 12.50 8.0 7.0M6 1 6.48 5.52 5.39 5.21 4.0 3.0 M16 2 16.70 15.30 14.77 14.50 9.0 8.0M8 1:25 8.58 7.42 7.26 7.04 5.0 4.0 M20 2:5 20.84 19.16 18.49 18.16 11.0 10.0M10 1:5 10.58 9.42 9.08 8.86 6.0 5.0 M24 3 24.84 23.16 22.13 21.80 13.0 12.0

Metric Heavy Hex Bolts (ANSI B18.2.3.6M-1979, R1989)M12 1:75 12.70 11.30 10.95 10.68 7.0 6.0 M20 2:5 20.84 19.16 18.49 18.16 11.0 10.0M14 2 14.70 13.30 12.77 12.50 8.0 7.0 M24 3 24.84 23.16 22.13 21.80 13.0 12.0

Metric Heavy Hex Flange Screws (ANSI B18.2.3.9M- 1984)M10 1:5 10.00 9.78 9.08 8.86 6.0 5.0 M16 2 16.00 15.73 14.77 14.50 9.0 8.0M12 1:75 12.00 11.73 10.95 10.68 7.0 6.0 M20 2:5 20.00 19.67 18.49 18.16 11.0 10.0

TABLE 18-53

Recommended diameter-length combinations for metric heavy hex structural bolts

All dimensions are in millimeters

Bolts with lengths above the heavy cross lines are threaded full length

TABLE 18-54

American National Standard metric hex nuts, Styles 1 and 2 (ANSI B18.2.4.1M and B18.2.4.2M-1979, R1989)

and thread

Metric Hex Nuts—Style 1

All dimensions are in millimeters

18.74

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TABLE 18-55

American National Standard metric slotted hex nuts (ANSI B18.2.4.3M-1979, R1989)

Nominal nut flats, corners, Thickness, face diam, thickness, of slot, face thickness,

All dimensions are in millimeters

furnished

3 Black, P H., and O E Adams, Jr., Machine Design, McGraw-Hill Publishing Company, New York, 1955.

4 Baumeister, T., ed., Marks’ Standard Handbook for Mechanical Engineers, 8th ed., McGraw-Hill Publishing Company, New York, 1978.

5 Lingaiah, K., and B R Narayana Iyengar, Machine Design Data Handbook, Engineering College Cooperative Society, Bangalore, India, 1962.

6 Lingaiah, K., and B R Narayana Iyengar, Machine Design Data Handbook, Vol I (SI and Customary Metric Units), Suma Publishers, Bangalore, India, 1986.

7 Lingaiah, K., Machine Design Data Handbook, Vol II (SI and Customary Metric Units), Suma Publishers, Bangalore, India, 1986.

8 Bureau of Indian Standards.

16 Little, R E., Bolted Joints: How Much Give? Machine Design, Nov 9, 1967.

17 Osgood, C C., Saving Weight on Bolted Joints, Machine Design, Oct 25, 1979.

18 Bowman Distribution-Barnes Group, Fastener Facts, Cleveland, Ohio, 1985, p 90.

19 American National Standards, ANSI B18.2.3.5M-1979, R1989.

20 British Standards Institution, 2 Park Street, London, 1986.

21 Machinery Handbook, 20th ed., 1999, Industrial Press, U.S.A.

22 Shigley J E., and C R Mischke, Standard Handbook of Machine Design, McGraw-Hill Publishing Company New York, 1996.

23 Lingaiah, K., Machine Design Data Handbook, McGraw-Hill Publishing Company, New York, USA, 1994.

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external area, m2(in2)

Ar radiating surface required, m2(in2)

Ac contact area of friction surface, m2(in2)

width of shoe, m (in)

width of inclined face in grooved rim clutch, m (in)

width of spring in centrifugal clutch, m (in)

width of wheel, m (in)

width of operating lever (Fig 19-16), m (in)

c heat transfer coefficient, kJ/m2K h (kcal/m2/8C/h)

c1 specific heat of material, kJ/kg K (kcal/kg/ 8C)

c2 radiating factor for brakes, kJ/m2K s (kcal/m2/min/ 8C)

d diameter of shaft, m (in)

diameter of pin, roller pin, m (in)

d1 diameter of bolt, m (in)

diameter of pin at neck in the flexible coupling, m (in)

d2 diameter of hole for bolt, m (in)

d0 outside diameter of bush, m (in)

D diameter of wheel, m (in)

diameter of sheave, m (in)

outside diameter of flange coupling, m (in)

D1 inside diameter of disk of friction material in disk clutches and

brakes, m (in)

D2 outside diameter of disk of friction material in disk clutches and

brakes, m (in)

Di inside diameter of hollow rigid type of coupling, m (in)

Do outside diameter of hollow rigid type of coupling, m (in)

Dm mean diameter, m (in)

e1, e2, e3 dimensions shown in Fig 19-16, m (in)

E energy (also with suffixes), N m (lbf in)

Young’s modulus of elasticity, GPa (Mpsi)

F operating force on block brakes, kN (lbf ); force at each pin in

the flexible bush coupling, kN (lbf ) total pressure, kN (lbf )

force (also with suffixes), kN (lbf )

actuating force, kN (lbf )

F1 tension on tight side of band, kN (lbf )

the force acting on disks of one operating lever of the clutch

(Fig 19-16), kN (lbf )

F2 tension on slack side of band, kN (lbf )

Fa0 total axial force on i number of clutch disks, kN (lbf )

Fb tension load in each bolt, kN (lbf )

Fc centrifugal force, kN (lbf )

Fn total normal force, kN (lbf )

Fx, Fy components of actuating force F acting at a distance c from the

hinge pin (Figs 19-25 and 19-26), kN (lbf )

F
tangential force at rim of brake wheel, kN (lbf )

tangential friction force, kN (lbf )

g acceleration due to gravity, 9.8066 m/s2(9806.6 mm/s2)

(32.2 ft/s2)

h thickness of key, m (in)

thickness of central disk in Oldham’s coupling, m (in)

thickness of operating lever (Fig 19-16), m (in)

depth of spring in centrifugal clutch, m (mm)

H rate of heat to be radiated, J (kcal)

Hg heat generated, J (kcal)

Hd the rate of dissipation, J (kcal)

number of bolts,

number of rollers,

pairs of friction surfaces

number of shoes in centrifugal clutch

number of times the fluid circulates through the torus in one

second

i1 number of driving disks

i2 number of driven disks

i0 number of operating lever of clutch

I moment of inertia, area, m4, cm4(in4)

kl load factor or the ratio of the actual brake operating time to the

total cycle of operation

l length (also with suffixes), m (in)

length of spring in centrifugal clutch measured along arc,

m (in) length of bush, m (in)

L dimension of operating lever as shown in Fig 19-16

Mt torque to be transmitted, N m (lbf in)

Mta allowable torque, N m (lbf in)

N normal force (Figs 19-25 and 19-26), kN (lbf )

N frictional force (Figs 19-25 and 19-26), kN (lbf )

p unit pressure, MPa (psi)

19.2 CHAPTER NINETEEN

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p unit pressure acting upon an element of area of the frictional

material located at an angle
from the hinge pin (Figs 19-25 and 19-26), MPa (psi)

maximum pressure between the fabric and the inside of the rim,

MPa (psi)

pa allowable pressure, MPa (psi)

maximum pressure located at an angle
afrom the hinge pin

(Figs 19-25 and 19-26), MPa (psi)

pb bearing pressure, MPa (psi)

P total force acting from the side of the bush on operating lever

rm mean radius, m (in)

rmi mean radius of inner passage of hydraulic coupling, m (in)

rmo mean radius of outer passage in hydraulic coupling, m (in)

R reaction (also with suffixes), kN (lbf )

Rc radius of curvature of the ramp at the point of contact

(Fig 19-21), m (in)

Rd radius of the contact surface on the driven member (Fig 19-21),

m (in)

Rr radius of the roller (Fig 19-21), m (in)

Rx, Ry hinge pin reactions (Figs 19-25 and 19-26), kN (lbf )

t time of single clutching or braking operation (Eq 19-198), s

Ta ambient or initial temperature, 8C (8F)

Tav average equilibrium temperature, 8C (8F)

T rise in temperature of the brake drum, 8C (8F)

tc cooling time, s (min)

v1, v2 speed of the live load before and after the brake is applied,

respectively, m/s

w axial width in cone brake, m (in)

width of band, m (in)

weight of the fluid flowing in the torus, kN (lbf )

weight lowered, kN (lbf )

weight of parts in Eq (19-136), kN (lbf )

weight of shoe, kN (lbf )

 stress (also with suffixes), MPa (psi)

b allowable or design stress in bolts, MPa (psi)

0

b design bearing stress for keys, MPa (psi)

db design bending stress, MPa (psi)

 shear stress, MPa (psi)

b allowable or design stress in bolts, MPa (psi)

d1 design shear stress in sleeve, MPa (psi)

d2 design shear stress in key, MPa (psi)

f design shear stress in flange at the outside hub diameter, MPa (psi)

s design shear stress in shaft, MPa (psi)

 one-half the cone angle, deg

pressure angle, deg