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Table 336. Effect of Pressure Upon Viscosity

Table 336. Effect of Pressure Upon Viscosity

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T A B L E 337.-LU



335



B R IC A N T S



With very few exceptions present-day lubricants are petroleum products or blends of

petroleum products with various compounding or addition agents such as fatty oils, diversified types of soap, and in rare instances solid materials such as graphite. Addition agents

are more costly than petroleum derivatives; hence they are used as sparingly as possible.

The addition agents are generally employed when conditions of use require greater “oiliness’’ (higher film strength) than is attainable with unblended petroleum oils. The latter

usually deteriorate more slowly in service than blended products, which is an advantage

supplementing that of low relative cost. There are a few jobs of lubrication for which

fatty oils have never been entirely supplanted, as for example the use of porpoise-jaw oil

in fine watches.



Lubricants for Cutting Tools



Various types of oils have been used as lubricants for cutting tools. These are fatty oils, kerosene, turpentitle, mineral oils and various blends of these oils. Sulfur has been combined with

some of these oils to increase the film strength. Such mixtures and blends are furnished by the

various manufacturers under their trade names such as Pennex, Dortan, Fanox, and Kutwell by

the Standard Oil Co. of New Jersey.

Ferrous

(more than

Severity

1 (greatest)

3

2

3

4

4



5



7

8

9



I9O



Type of operation

Broaching, internal

Tapping, plain

Threading pipe

Threading: plain

Gear shaving

Gear cutting

Driiling, deep

Boring, multiple head

Hiah-soeed. liahtfeed; automitic

screwmachines

Turning; singlepoint tool, form

tools



70%)



Ferrous



Ferrous

(less than



(50-65%)



Em Sulf

Sulf

Sulf

Sulf

Sulf L

Sulf M L E m

Em M L

Sulf Em



Sulf

Sulf

Sulf

Sulf

Sulf

Sulf

Sulf

Sulf



Sulf Em M L

Em Sulf M L



Em

ML



L



40%)



Sulf

Sulf

Sulf

Sulf

Sulf

Sulf

Sulf

Sulf



Em



L

ML



Nonferrous

(more than

100%)



MO Em

E m Dry



Em

-



Sulf



Nonferrous

(less than

100%)



Sulf MISulf M L

Sulf

Sulf



-



Em



MO M L E m

K Dry E m



Sulf M L

Sulf M L

Sulf Em



Sulf Em M L



Sulf M L E m



E m Dry M L



Sulf



E m Sulf M L



Em Sulf M L



Em Dry M L



Em Sulf



Em

Em



Metals Handbook, 1948 ed., p. 69, American Society for Metals, Cleveland.



Symbols: D i y = no cutting fluid, E m = soluble or emulsifiable oils and compounds, K

ML = mineral-lard oils, M O = mineral oils, Sxlf = sulfurired oils.



SMITHSONIAN PHYSICAL TABLES



= kerosene, L = lard



oil,



336



T A B L E 338.-FRICTION



The required force F necessary to just move an object along a horizontal plane = f N

where N is the normal pressure on the plane and .f the "coefficient of friction." The angle

of repose (tan = F / N ) is the angle at which the plane must be tilted before the object

will m6ve from its own weight . The following table of coefficients was compiled by Rankine

from the results of General Morin and other authorities and is sufficient for ordinary

purposes .



+



+



f



Material



Wood on

wood. dry .............................

I'

soapy. ...........................

Mepls o

; o:k. dry ..............................

wet ..............................

"

"

"

soapy ............................

"

"

elm. dry ..............................

Henip on oak. dry ...............................

I'

'1

wet ...............................

Leather on oak .................................

" metals. dry ..........................

"

wet ..........................

greasy .......................

"

oily ..........................

Metals

on

metals.

dry ...........................

"

"

"

wet ...........................

Smooth surfaces. occasionally greased .............

continually greased ..............

"

best results .....................

Stzel 9!1 a p e . dry ..............................

oiled .............................

Iron on stone ...................................

Wood on stone .................................

M a s y r y ?!I brkk w y k , dry .....................

damp mortar ............

"

"

dry clay ............................

"

I'

moist clay ..........................

Earth on earth .................................

dry sand. clay. and mixed earth ...

"

I'

"

damp clay ......................

"

"

81

wet clay ........................

'I

"

"

shingle and gravel ...............

'1



t'



'1



6

'



' I



'1



'I



.



......



SMITHSONIAN PHYSICAL TABLES



.25-. 50

.20

.50-. 60

.24-. 26

.20

.20-. 25

53

.33

.27-. 38

.56

.36

.23

.15

.15-. 20

.3

.07-. 08

.05

.03-. 036

.20

.107

.3&. 70

About .40

.60-. 70

.74

51

.33

.25- 1.00

.38-. 75

1.00

.31

31-1.11



.



.



1/ f

4.00-2.00

5.00

2.00-1.67

4.17-3.85

5.00

5.00-4.00

1.89

3.00

3.70-2.86

1.79

2.78

4.35

6.67

6.67-5.00

3.33

14.3-12.50

20.00

33.3-27.6

5.00

9.35

3.33-1.43

2.50

1.67-1.43

1.35

1.96

3.00

4.00-1 .00

2.63-1.33

1.00

3.23

1.23-.9



m



14.0-26.5

11.5

26.5-31.0

13.5-14.5

11.5

11.5-14.0

28.0

18.5

15.0-19.5

29.5

20.0

13.0

8.5

8.5-11.5

16.5

4.0-4.5

3.0

1.75-2.0

11.5

6.1

16.7-35.0

22.0

33.g35.0

36.5

27.0

18.25

14.0-45.0

21.0-37.0

45.0

17.0

39.0-48.0



TABLES 339-346A.-AERONAUTICS

TABLE 339.-DYNAMIC



*



337



PRESSURE A T DIFFERENT A I R SPEEDS



The force on a body moving through a fluid may be expressed in the form

F=Cpq A

where F is the force, CF a nondimensiona: force coefficient, q the dynamic pressure ( q =

jpV', definition), and A a n area. In general, the value of the coefficient CF is dependent

on several nondimensional parameters. When the medium is air, CF depends on the

VlP

V

Reynolds number -, the Mach number -' the body shape and attitude to the relative

r)

a

wind, the relative surface roughness, and the degree of turbulence of the air stream. The

quantity p denotes the fluid density, V the velocity of the body relative to the fluid, q the

coefficient of fluid viscosity, 1 a linear dimension of the body fixing the scale, and a the

speed of sound in the ambient fluid.

The table gives values of dynamic pressure q for a wide range of speeds. In conjunction

with the values of the force coefficient in subsequent tables, this table can be used for

computation of lift, drag, and moment under specified conditions. T h e values in the table

are computed for standard air density: dry air, normal CO, content, 15"C,one atmosslugs

metric slugs

or 0.002378 --.For

standard gravity,

phere. Standard air density is 0.12497

ft8

ma

the weight of one metric slug (MKS) is 9.807 kilograms and the weight of one slug is

32.174 pounds. For other densities the values must be multiplied by the ratio of the actual

density to the standard density.

Tables 339 to 346 and figures 6 to 1 5 were prepared under the direction of C. H. Helms, assistant

director of aeronautical research, National Advisory Committee for Aeronautics.



(continued)



SMITHSONIAN PHYSICAL TABLES



w

w



03



T A B L E 339.-DYNAMIC



PR ESSU R E A T D I F F E R E N T A I R SPEED S (concluded)



Dynamic

pressure, q

kg/m2



Air

speed

m/sec



Dynamic

pressure, q

Wm2



Air

speed

m/sec



D y n a m ic

pressure, q

kg/m2



Air

speed

m/sec



.0625

.2499

S624

.W8

1.562

2.249

3.062

3.999

5.061

6.248



12

14

16



35

4c

45

50



60

65

70

75

80



76.54

99.98

126.5

156.2

189.0

224.9

264.0

306.2

351.5

399.9



85

90

95



20

22

24

26

28

30



8.998

12.25

16.00

20.24

24.99

30.24

35.99

42.24

48.99

56.24



;2ir

speed

ft/sec



Dynamic

pressure, q

lb/W



Air

speed

ft/sec



Dynamic

pressure, q

Ib/ft*



Air

speed

ft/sec



1

2

3

4

5

6

7

8

8

10



.0012

.0048

.0107

.0190

.0297

.0428

.0583

,0761

.0963

.1189



20

30



,4756

1.0701



Air

speed

m/sec



1

2



18

.~



Dynamic

pressure, q

kg/m2



1no



1



4.280

5.826

7.610

9.631

11.890

14.39



Dynamic

pressure, q



kdm*



110

120

130

140

150

160



451.4

506.1

563.9

624.8

756.1

899.8

1056.0

1225

1406

1600



170

180

190

200

250

350

400

450

500



1806

2024

2256

2499

3905

5624

7654

9998

12653

15621



Dynamic

pressure, q

lb/ft2



Air

speed

ft/sec



Dynamic

pressure, q

lb/ft2



Air

speed

ft/sec



Dynamic

pressure, q

Ib/ft2



120

130

140



17.12

20.09

23.30



220

230

240



57.55

62.90

68.49



160

170

180

190

200

210



30.44

34.36

38.52

42.92

47.56

52.43



300

350

400



107.01

145.6190.2

240.8

297.2

359.7



600

650

700

750



428.0

502.4

582.6

668.8

761.0



5s

._



100



..



60

70

80

90



Air

speed

m/sec



.-"



AW



500

550



3nn

.__



800



1500



2675



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