67071_13.pdf

CHAPTER

13 RIVETED JOINTS

S Y M B O L S 2,3,4

d

Di e o r l F h

he, hi, h2 i

I J

F K ~

F '

m Mb P Pc Pd Pt el Z

o- o

aa O" c

T

~-a

~7 0

area of cross-section, m 2 (in 2) the cross-sectional area of rivet shank, m 2 (in 2) breadth of cover plates (also with suffixes), m (in) distance from the centroid of the rivet group to the critical rivet,

m (in) diameter of rivet, m (in) internal diameter of pressure vessel, m (mm) eccentricity of loading, m (in) force on plate or rivets (also with suffixes), kN (lbf) thickness of plate or shell, m (in) thickness of cover plate (butt strap), m (in) number of rivets in a pitch fine (also with suffixes 1 and 2,

respectively, for single shear and double shear rivets) moment of inertia, area, m 4, cm 4 (in 4) moment of inertia, polar, m 4, cm 4 (in 4)

coefficient (Table 13-11)

margin, m (in) bending moment, N m (lbf in) pitch on the gauge line or longitudinal pitch, m (in) pitch along the caulking edge, m (in) diagonal pitch, m (in) transverse pitch, m (in) intensity of fluid pressure, MPa (psi) section modulus of the angle section, m 3, cm 3 (in 3) hoop stress in pressure vessel or normal stress in plate, MPa

(psi) allowable normal stress, MPa (psi) crushing stress in rivets, MPa (psi) shear stress in rivet, MPa (psi) allowable shear stress, MPa (psi) efficiency of the riveted joint angle between a line drawn from the centroid of the rivet group to the critical rivet and the horizontal (Fig. 13-5)

13.1

13.2 CHAPTER THIRTEEN

Particular Formula

PRESSURE VESSELS

Thickness of main plates

The thickness of plate of the pressure vessel with longitudinal joint

For thickness of boiler plates and suggested types of joints

The thickness of plate of the pressure vessel with circumferential joint

For allowable stress and efficiency of joints

h - - - e f o i (13-1) 2r/cro

Refer to Tables 13-1 and 13-2.

h -- e f o i (13-2) 4r/o-o

Refer to Tables 13-3, 13-4, 13-5, and 13-6.

PITCHES

Lap joints

The diagonal pitch (staggered) (Fig. 13-1) for p, Pt, and Pa

The distance between rows or transverse pitch or back pitch (staggered)

The rivet diameter

i.,. FIGURE 13-1 Pitch relation

2p+d Pd = 3 (13-3)

Refer to Tables 13-7 and 13-8 for rivets for general purposes and boiler rivets.

pt=~(2pf d )2 _ (~p)'~2 (13-4)

d = O. 19x/h to 0 . 2 ~ SI (13-5a)

where h and d in m

d = 1.2x/-h to 1.4v/h USCS (13-5b)

where h and d in in

d - 6x/h to 6.3v/-h CM (13-5c)

where h and d on mm

T A B L E 13-1 Suggested types of joint

Diameter of shell, mm (in) Thickness of shell, mm (in) Type of joint

600-1800 (24-72) 900-2150 (36-84)

1500-2750 (60-108)

6-12 (0.25-0.5) 7.5-25 (0.31-1.0) 9.0-44 (0.375-1.75)

Double-riveted Triple-riveted Quadruple-riveted

RIVETED JOINTS 13.3

TABLE 13-2 Minimum thickness of boiler plates

Shell plates

Diameter of shell, mm (in)

Minimum thickness after flanging, mm (in)

Tube sheets of firetube boilers

Diameter of tube sheet, mm (in)

Minimum thickness, mm (in)

_<900 (36) 900-1350 (36-54) 1350-1800 (54-72) >IO,,,, _ our (72)

6.0 (0.25) 8.0 (0.3125) 9.5 (0.375)

12.5 (0.5)

_< 1050 (42) 1050-1350 (42-54) 1350-1800 (54-72)

< i800 (72)

9.5 (0.375) 11.5 (0.4375) 12.5 (0.50) i4.0 (0.5625)

T A B L E 13-3 Efficiency of riveted joints 0/)

% Efficiency, ~/

Normal Type of joint range Maximum

Lap joints Single-riveted 50-60 63 Double-riveted 60-72 77 Triple-riveted 72-80 86.6

Butt joints (with two cover plates) Single-riveted 55-60 63 Double-riveted 76-84 87 Triple-riveted 80-88 95 Quadruple-riveted 86-94 98

T A B L E 13-4 Allowable stresses in structural riveting (crb)

Rivet-driving Load-carrying member Type of stress method

Rivets acting in single shear Rivets acting in double shear

MPa kpsi MPa kpsi

Rolled steel SAE 1020

Rivets, SAE 1010

Tension Shear Power

Shear Hand Crushing Power Crushing Hand

124 18.0 124 18.0 93 13.5 93 13.5

68 10.0 68 10.0 165 24.0 206 30.0 110 16.0 137 20.0

13.4 C H A P T E R T H I R T E E N

T A B L E 13-5 Allowable stress for aluminum rivets, o" a

Rivet alloy Procedure of drawing

Allowable stress a, O" a

Shear Bearing

MPa kpsi MPa kpsi

2S (pure aluminum) Cold, as received 17S Cold, immediately after quenching 17S Hot, 500-510°C 615-T6 Cold, as received 53S Hot, 515-527°C

20 3.0 48 7.0 68 10.0 179 26.0 62 9.0 179 26.0 55 8.0 103 15.0 41 6.0 103 15.0

a Actual safety factor or reliability factor is 1.5.

T A B L E 13-6 Values of working stress a at elevated temperatures

Maximum Minimum of the specified range of tensile strength of the material, MPa (kpsi)

temperatures (45) 311 (50) 344 (55) 380 (60) 413 (75) 517

°F °C MPa kpsi MPa kpsi MPa kpsi MPa kpsi MPa kpsi

0-700 0-371 61 9.0 68 10.0 76 11.00 82 12.00 103 15.00 750 399 56 8.22 62 9.11 68 10.00 77 11.20 89 13.00 800 427 45 6.55 53 7.33 54 8.00 61 9.00 70 10.20 850 455 37 5.44 41 6.05 46 6.75 51 7.40 57 8.30 900 482 29 4.33 33 4.83 37 5.50 38 5.60 41 6.00 950 511 22 3.20 26 3.60 27 4.00 27 4.00 27 4.00

a Design stresses of pressure vessels are based on a safety factor of 5.

T A B L E 13-7 Pitch of butt joints

Type of joint Diameter of rivets, d, mm Pitch, p

Double-riveted Any use for h _< 12.5 mm (0.5 in)

5.5d (approx.)

Triple-riveted-- use for h < 25 mm (1 in) Quadruple-riveted use for h < 31.75mm (1.25in)

1.75-23.80 27.00 30.15-36.50 17.50-23.80 27.00 30.15 33.30-36.50

8d-8.5d 7.5d 6.5d-7d 16d-17d 15d (approx.) 14d (approx.) 13d-14d

RIVETED JOINTS 13.5

T A B L E 13-8 Transverse pi tch (Pt) as per A S M E Boi ler C o d e

Value of p/d 1 2 3 4 5 6 7

Value of Pt 2d 2d 2d 2d 2d 2.2d 2.3d

Particular Formula

Butt joint

The transverse pi tch

Fo r rivetS, rivet holes, and s t rap thick

T A B L E 13-9 Rivet hole d i a m e t e r s

Diameter of rivet, mm Rivet hole diameters, mm (min)

12 13 14 15 16 17 18 19 20 21 22 23 24 25 27 28.5 30 31.5 33 34.5 36 37.5 39 41.0 42 44 48 50

I~ .............. l .... r---7"

Pt : 2d to 2.5d

Pt >-- v/O.5p d + 0.25d 2

Refer to Tables 13-9, 13' 10, and Fig. 13-2.

T A B L E 13-10 Rivet hole d iameters and s trap t h i c k n e s s

(13-6a)

(13-6b)

Minimum Minimum Plate strap Hole Plate strap Hole thickness, thickness, diameter, thickness, thickness, diameter, h, mm hc mm d, mm h, mm h~ mm d, mm

6.25

7.20 6.25 17.50

8.00 8.75 20.50

9.50

10.30 8.00

11.10

12.00 9.50 24.00

12.50

13.50 11.10

14.25 11.10

27.0

15.90 12.50

19.00 30.15

22.25 15.90 33.30

25.00 12.50

28.50 19.00 36.50

31.75 22.25

83.10 25.00 39.70

FIGURE 13-2 Quadruple-riveted double-strap butt joint.


Particular Formula

Minimum transverse pitch as per A S M E Boiler Code

For transverse pitches

Haven and Swett formula for permissible pitches along the caulking edge of the outside cover plate

Diagonal pitch, Pd, is calculated from the relation

M A R G I N

Margin for longitudinal seams of all pressure vessels and girth seams of power boiler having unsupported heads

Margin for girth seams of power boilers having supported heads and all unfired pressure vessels

C O V E R P L A T E S

The thickness of cover plate

Pt -- 1.75d if p ~___4

Pt = 1.75d + 0 . 0 0 1 ( p - d) if p ~ > 4

where Pt, P, and d in m

p t = l . 7 5 d + O . l ( p - d ) if p~>4

where Pt, d, and p in in

Refer to Table 13-8.

14 4 h/-~[3 p c - d - f - ~ f

where Pc, d, hc in cm, and PI in kgf/cm 2

4N Pc - d = 2 1 . 3 8 g ~ f

where Pc, d, hc in in, and Pf in psi r - - - - -

P c - d = 77.8 4/h3 Vg

where Pc, d, hc in m, and Pf in N/m 2

2(pd - d) >_ ( p - d)

(13-7a)

SI (13-8a)

USCS (13-8b)

CM (13-9a)

USCS (13-9b)

SI (13-9c)

(13-10)

m = 1.5d to 1.75d (13-11a)

m > 1.25d n (13-11b)

h c = 0 . 6 h + 0 . 0 0 2 5 if h _< 0.038 m

where hc and h in m

h c = 0 . 6 h + 0 . 1 if h<_ 1.5in

where hc and h in in

hc -- 0.67h if h > 0.038m

where hc and h in m

hc=O.67h if h > 1.5in

where hc and h in in

SI (13-12a)

USCS (13-12b)

SI (13-12c)

USCS (13-12d)

R I V E T E D J O I N T S 13.7

T A B L E 13-11 R i v e t g r o u p s u n d e r e c c e n t r i c l o a d i n g v a l u e o f c o e f f i c i e n t K

,,,P,ig2 1 Case 1

- o - , o ~11, ~P~ _~.~_ -e-,,

t "-( . ) - - I - - ~ -

~' t - ( ")-- "1-- " l~-

(--- P--~I

Case 3

Case 4

_ .1_ pt

Case 5

| I

Case 6

K = - -

K =

K -

K -

K =

tp 1 k

p2 + p 2 4

2--7- + -SY + 1

H.'

Case 2

l ( r t - 1 ) p t 2 112 + ½ (n 2 - 1)p 2 +

p~+½(~ 1)p, ~ + _ p2

tp 1] 2

+ ½ (~ - 1)p, ~ + 5

l(n - 1)pt )2 (p~ +p2 +Z(nZ_ l)p2 + (p2 + p2 + 2 (n 2 _ 1)p2 +

K = (I 6, ]2 (n + 1)pt

+ 1

Key: n = total number of rivets in a column F = permissible load, acting with lever arm, l, kN (lbf) F' -- permissible load on one rivet, kN (lbf) K = F/F', coefficient Source: K. Lingaiah and B. R. Narayana Iyengar, Machine Design Data Handbook (fps Units), Engineering College Cooperative Society, Bangalore, India, 1962; K. Lingaiah and B. R. Narayana Iyengar, Machine Design Data Handbook, Vol. I (SI and Customary Metric Units), Suma Publishers, Bangalore, India, 1983; and K. Lingaiah, Machine Design Data Handbook, Vol. II (SI and Customary Metric Units), Suma Publishers, Bangalore, India, 1986.


Particular Formula

Thickness of the cover plate according to Indian Boiler Code

Thickness of single-butt cover plate

Thickness of single-butt cover plate omitting alternate rivet in the over rows

Thickness of double-butt cover plates of equal width

Thickness of double-butt cover plates of equal width omitting alternate rivet in the outer rows

Thickness of the double-butt cover plates of unequal width

For thickness of cover plates

The width of upper cover plate (narrow strap)

The width of lower cover plate (wide strap)

h 1 = 1 . 1 2 5 h

h 2 -- 1.25h p - d p - 2d

hc = hi = h2 = 0.625h

hc = hi = h2 -- 0.625h p - d p - 2d

h 1 : 0.625h for narrow strap

h2 --0.750h for wide strap


bl = 4m + 2p t I

b2 -- bl + 2pt2 "a t- 4m

(13-13)

(13-14)

(13-15)

(13-16)

(13-17a)

(13-17b)

(13-18)

(13-19)

S T R E N G T H A N A L Y S I S O F T Y P I C A L R I V E T E D J O I N T ( F i g . 13-2)

The tensile strength of the solid plate

The tensile strength of the perforated strip along the outer gauge line

The general expression for the resistance to shear of all the rivets in one pitch length

The general expression for the resistance to crushing of the rivets

The resistance against failure of the plate through the second row and simultaneous shearing of the rivets in the first row

The resistance against failure of the plate through the second row and simultaneous crushing of the rivets in the first row

The resistance against shearing of the rivets in the outer row and simultaneous crushing of the rivets in the two inner rows

Fo = phao

Fo = ( p - d)hcro

7rd 2 F~ = (2i 2 + il) - ~ r

F c = (i2h + ilh2)dcrc

7cd 2 F~I = ( p - 2d)hcro + ~ "1-

Fcl + ( p - 2d)hao + dhac

7r Fro = -~ d2"r + idhcr c

(13-20)

(13-21)

(13-22)

(13-23)

(13-24)

(13-25)

(13-26)

RIVETED JOINTS 13.9

Particular Formula

E F F I C I E N C Y O F T H E R I V E T E D J O I N T

The efficiency of plate

The efficiency of rivet in general case

For efficiency of joints

The diameter of the rivet in general case

The pitch in general case

For pitch of joint

p - d

P

7rd 2 7-(il 4- 2/2)

4phao

h2 (i2+/1 ( ha)

i 24- i l -ff Crc4-Cr 0


d ..__ 4hi2 + i 1 h2o" c

7r(il 4- 2/2)~-

Note: for lap joint/2 = 0 for butt joint il = 0

(2i2 + il )Trd 27- + d

p = 4her °


(13-27)

(13-28)

(13-29)

(13-30)

T H E L E N G T H O F T H E S H A N K O F R I V E T (Fig. 13-3)

X Y

I

"-I

0.5D

/" 5 diameters long and under

FIGURE 13-3

t D

L -- h + hi 4- h2 4- (1.5 to 1.7)D

L -- h + hc + (1.5 to 1.7)D

for butt joint with single cover plate

L --- 2h 4- (1.5 to 1.7)D

for lap joint

where D - diameter of rivet

(13-31a)

(13-31b)

(13-31c)


Particular Formula

S T R U C T U R A L J O I N T

R i v e t i n g of an ang le to a g u s s e t plate (F ig . 13-4)

The resultant normal stress

g

,,,.a IF --H~

! ~ ~ ~ - , _ - 1 ~_~

g e (a)

F

a , i

FIGURE 13-4 Riveting of an angle to a gusset plate.

Fe

Z

i F

(13-32)

R I V E T E D B R A C K E T (Fig. 13-5)

The resultant load on the farthest rivet whose distance is c from the center of gravity of a group of rivets (Fig. 13-5)

FR = ~ -+- E x 2 .+. E y 2

nn--5 ~ X 2 + ~ y2 COS 0

, jF

~,, Z , - ~

, ,4, 1 , 4 , ' / '+'-I ' f

J

Axial load -x~ F I j F MbC At,

F + ""1~ / oment an' ~ ? / ~ c o u p l e , o

i

F~_.._ Moment couple

FIGURE 13-5 Riveted bracket. (Bureau of Indian Standards.)

(13-33)

RIVETED JOINTS 13.11

Particular Formula

For rivet groups under eccentric loading value of coefficient K

For preferred length and diameter of rivets

For collected formulas of riveted joints

where

n = number of rivets in one column n' number of rivets in one row x, y have the meaning as shown in Fig. 13-5


Refer to Figs. 13-6 to 13-8 and Tables 13-12 to 13-13.


R r V r R r N C r S

1. Maleev, V. L., and J. B. Hartmen, Machine Design, International Textbook Company, Scranton, Pennsylvania, 1954. ~

2. Lingaiah, K., and B. R. Narayana Iyengar, Machine Design Data Handbook (fps Units), Engineering College Cooperative Society, Bangalore, India, 1962..~

3. Lingaiah, K., and B. R. Narayana Iyengar, Machine Design Data Handbook, Vol. I (SI and Customary Metric Units), Suma Publishers, Bangalore, India, i983. ~

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

5. Bureau of Indian Standards. ~ 6. Lingaiah, K., Machine Design Data Handbook, McGraw-Hill Publishing Company, New York, 1994.

B I B L I O G R A P H Y

Faires, V. M., Design of Machine Elements, The Macmillafi Company, New York, 1965. Norman, C. A., E. S. Ault, and I. F. Zarobsky, Fundamentals of Machine Design, The Macmillan Company, New

York, 1951. Vallance, A., and V. L. Doughtie, Design of Machine Members, McGraw-HiU Publishing Company, New York,

1951.


i-" 1"6d--'~ i-" 1"6d"~1 O~d ~ ~ , O'{Td J ~ d - ~ O'}d

2.25d -' ;-<1 1 "5~6d

~ d

Snap Head Pan Head Mushroom Head Countersunk Head

O" 3d • 0"25d ) : - t oo ~ t t C

t "

Flat Countersunk Flat Countersunk Round Countersunk Flat Head Head 90 ° Head 60 ° Head 60 °

FIGURE 13-6 Rivets for general purposes (less than 12 mm diameter). For preferred length and diameter combination, refer to Table 13-12.

Snap Head Pan Head

• - 1.5D -'

¢--

i -

_ J

Rounded Countersunk Head

U 1 . 5 D "~i

¢-.

¢.-

_ J

Flat Countersunk Head

r t '1 0"7D k

t t,' ~.6o_~0-,o g

_ J

t Pan Head with Tapered Neck

2D

¢-. (33 ¢- ._J

Flat Head FIGURE 13-7 Rivets for general purposes (12 to 48 mm diameter). For preferred length and diameter combination, refer to Table 13-13.

RIVETED JOINTS 13.13

=-! I

!-- o ;I SNAP HEAD

/ / ~ 1 " 6 t -,- 1.7 D ,q D 4.1m~ 0"6D i

I 0. D

i ELLIPSOID HEAD

i ~ D

/ o.7 ' I c'- r,

,_J

PAN HEAD, TYPE 1

f D

1

t-0.125D

I-" D--~ f

'

E

" I~11 "4D AN D_.LJ i L 13D~e.~T'

] .4D For Rivets under 24 mm 1.3D For Rivets 24 mm and over

PAN HEAD, TYPE 2 t

COUNTERSUNK HEAD

_1 ).125D ~'

{33 ,- 60

/ - r = 0.063 D ~

: t - - I - ' k ~6o l . I ~, ' - ~ - ' t

r- D ~i 1 t ~ o . ~ s D

0.7D

4 ( ~ - ~ ~ '~2 ° 0.5D + ' !: ~, 1-6D 7-~i [0.~25D

I: o ~! , ;~6o/ PAN HEAD, WITH

TAPERED NECK CONICAL HEAD

t-

t-

J

1 SEETPLE HEAD

i

Round Countersunk Head

FIGURE 13-8 Boiler rivets (12 to 48mm diameter). For preferred length and diameter combination, refer to Table 13-13.

13.14 C H A P T E R T H I R T E E N

T A B L E 1 3 - 1 2

Preferred length ( x ) and diameter combinations for rivets (Fig. 13-6)

Diameter, mm

Length, mm 1.6 2 2.5 3 4 5 6 8 10

5 X - -

6 x x x x

7 x x x x

8 x x x x x

9 x x x x x

10 x x x x x

12 ~ x x x x

14 ~ x x x

16 ~ ~ x x x

18 ~ ~ -- x x

20 - - - - -- x x

2 2 ~ - - - - x x

2 4 ~ x x

26 -- ~ ~ x x

28 x x

30 x x

35 -- -- x x

40 x

45 -- x

50 ~ --

55

60 -- -- --

65 . . . . .

70

Source: Bureau of Indian Standards, IS: 2155, 1962.

X

X

X

X

X

X

X

X

X

X

X

X

X

X

X

R I V E T E D J O I N T S 13 .15

T A B L E 1 3 - 1 3

Preferred lengths ( x ) and diameter combinations of rivets (Fig. 13-7)

Diameter, mm

Length, mm 12 14 16 18 20 22 24 27 30 33 36 39 42 48

2 8 x

3 1 . 5 x x

3 5 . 5 x x x

4 0 x x x x

4 5 x x x x x

5 0 x x x x x x - - - -

5 6 x x x x x x x

63 x x x x x x x x

71 x x x x x x x x x

8 0 x x x x x x x x x


9 0 x x x x x x x x x - -

95 x x x x x x x x x x

1 0 0 x x x x x x x x x


1 1 2 x x x x x x x x x x



1 3 2 x x x x x x x x

1 4 0 -- ~ x x x x x x x x

1 5 0 x x x x x x x

1 6 0 -- x x x x x x x

1 8 0 - - x x x x x x

2 0 0 x x x x x

2 2 4 - - x x x x

2 5 0 . . . . x

Source: B u r e a u o f I n d i a n S t a n d a r d s , IS: 1929, 1961.

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