Download - Coeficientes de Perdidas Locales en Accesorios CRANE

8/20/2019 Coeficientes de Perdidas Locales en Accesorios CRANE

http://slidepdf.com/reader/full/coeficientes-de-perdidas-locales-en-accesorios-crane 1/4

A · 2 6 APPENDIX A PHYSICAL PROPERTIES OF FLUIDS AND FLOW CHARACTERISTICS OF VALVES, FITTINGS, AND PIPE CRA N E

K FACTOR TABLE-SHEET 1 of 4

Representative Resistance Coefficients (K) for Valves and Fittings( K is based on use o f schedule pipe as listed on page 2- 10)

PIPE FRICTION DATA FOR CLEAN COMMERCIAL STEel PIPEWITH FlOW IN ZONE OF COMPLETE TURBULENCE

Nominal Size Y2 711Friction .027 .025Factor (fT)

• Formula 1

• Formula 2

0, ; (I - (32) • Isin. ..1<2 = V 2

{34

1 1 ~ lY2 2 2Y2, 3 4 5

.023 .022 .021 .019 .018 .017 .016

FORMULAS FOR CALCULATING uK FACTORS·FOR VALVES AND FITTINGS WITH REDUCED PORT

(Ref: Pages 2-11 and 3-4)

• Formula 6

6 8-10

,015 .014

1<2 = ~ l+ Formula 2 -7- Formula ..J.

• Formul a 7

12-16

.013

18-24

.012

• Formula 3

2 6 ~ i n:1 1- (32)2 l

K = ~ 4+ { (Formula 2 + Formula..J.) when () = 180

K = {34 = {34

• Formula 4

• Formula 5

1<2 = ~ I+ Formula I + Formula 3

KI + i n ~ [ 0 8(r - (32) + 2,6 (I - (32)2]K2

= 2

SUDDEN AND GRADUAL CONTRACTION

9\

. I I

d, 1 a,\ \

If: < 45° K Formula I

45° < < r800 . • . K - Formula 2

{3 - ~- d

2

{32 = dl )2 = c: . .d2 a2

Subscript 1 defines dimensionsand coefficients with reference t othe smaller diameter.Subscript 2 refers to the largerdiameter

SUDDEN AND GRADUAL ENLARGEMENT

r;:\ I, I I ,

I I \I , ~ d, 9 d, I a, 1, I I / \ \ I, .-

L: 5

If: < 45°· , .1<2 = Formula 3

45° < < 180 0• • • 1<2 = Formula 4



C R A N E APPENDIX A - PHYSICAL PROPERTIES OF flUIDS AND FLOW CHARACTERISTICS OF VALVES. FITTING S. AND PIPE A-27


Representat ive Resistance Coefficients (K) for Valves and Fittings(for formulos and friction data. see poge A·26)

( K is based on use of schedule pipe as listed on page 2· 10)

GATE VALVES SWING CHECK VALVESWedge Disc, Double Disc, or Plug Type

If: {3 = I, j = 0 . 1< = 8fT

{3 < 1 and (j :( -1-5°. . . . . . . . . ~ = Formula 5{3 < 1 and 45° < j '< 180° . 1 -2 = Formula l1

GLOBE AND ANGLE VALVES

4 .../ .'

/ \ . . , ,-, ' , . .

~_ _ ij , , -a , d a 'I . : ~s z

If: {3=I I<'=55fT

All ~ I o b eand a n ~ l evalves,whether reduced scat or throttled,

[ f: :J < I . . . f{., = Formula 7

, ,a., ,

K=loofT

\'Iinimum pipe \'elocityfpS) for full ,--lise lift

I< = 50 fr

\Iinimum pipe \'elocityfpS) for full disc lift

=35 VV- =48 VV

~ ..------, ~

LIFT CHECK VALVES

I r: r = I ,K 1 = oeo fTr < I ,K 2 = Formula 7

lvlinimum pipe velocity (fps) for full disc lift/ - = -

= 40 t/2 V V

~ , Irr- . i

If: r3=I I<1=55h·r < I . . . K2 = Formula i

~ I i n i m u r npipe velocity Ups) for full disc lift= 140 (32 v'v

TILTING DISC CHECK V ALVES

0(. = 5° 01.= 15°

Sizes 2 to 8 , . . K = 40ft. 120frSizes 1 0 to 14 . . . K = 30 ft L)O /7 '

Sizes I l) to -18 . . . K = 20/-1 bo fT\ linirnurn pipe velocity

80 VV 30 VVCps) for full disc lift =



A - 28 APPENDIX A - PHYSICAL PROPERTIES OF FLUIDS AND f l O W CHARACTERISTICS OF VALVES, FITTINGS, AND PIPE C R A N


Representative Resistance Coefficients (K) for Valves and FittingsFor formulas and friction data, see page A-26J

( K is based on use of scheduled pipe as listed on page 2- 10)

STOP-CHECK V ALVES

(Globe and Angle Types)

If:i = I, , ,1<1 = 40 0 fr{3

< I ,:1<2 = Formula 7

Minimum pipe velocityfor full disc Ii ft

= 55 {32 v'V

If:{3 = 1 - , 1<1 = JOO iT{3 < I , 1<.2 = Formula 7

If:{3 = I , I<I = 2 0 0 iT

{3 < I , , 1<2 = Formula ;

Minimum pipe velocityfor full disc lift

= 75 {32 VV

If:{3 = I , ,1<1 = 35 0 fr{3 < I , 1<.2 = Formula 7

ivlinimum pipe velocity (fps) for full disc lift

= 60 {32 VV

If: If:{3 = I , - ,K 1 = 55 iT{ J< I 1<.2 = Formula 7

{3 = I. I < I = 55 iT{ J< I 1<2 = Formula ;

Nlinimum pipe velocity (fps) for full disc lift

= 140 {32 V V

FOOT VALVES WITH STRAINER

Poppet Disc Hinged Disc

t--d--i

, I:;- . - . - - - z j

\ linimum pipe \'ciocity(fps) for full disc lift

\Iinimum pipe \'clocity(fps) for full disc. ift

= 15 VV =

= 35 V V

BALL VALVES

vJ;4 tIf: p = I . = 0 , , , , , , , , , , , I < I = J 1.

p < 1 and 0 <: 45° , , , , , , , , ,1\.2 = rormula 5{3 < I and 45° < 0 < 180°, , ,1\.2 = r:-ormula 6

UTTERFLY VALVES

Sizes 2 to 8 K = 45 r

Sizes 10 to 14" K = 35 r

Sizes 16 to 24" K = 25 iT



CRANE APPENDIX A - PHYSICAL PROPERTIES OF FLUIDS AND FLOW CHARACTERISTICS OF VALVES. FlnINGS. AND PIPE A-29

UK FACTOR TABLE- SHEET 4 of 4

Representative Resistance Coefficients (K) for Valves and Fittings(for formulas and friction dota, ee page A-26)

( K is based on use of schedule pipe as listed on page 2- 10)

PLUG VALVES AND COCKS

Straight-Way 3-Way

If: t = I .

1<\ = IS T

I f :

If: p = I If: j3 = I

I \ = 30 T 1<\ = ClOiT

11 < I < ~ = Formula 6

MITRE BENDS

0(.

O· 2 frIS· 4 fr30 8 fr45· 15 fr60· 25 fr75· 40 fr90· 60 fr

- - - - - - - - - - ~ - - - - - - - .

90° PIPE BENDS AND

FLANGED OR BUTT-WELDING 90° ELBOWS

rid rid

1 20 fr 8 24 fr1.5 14 fr 10 30 fr2 12 fr 12 34 fr3 12 fr 14 38 fr4 14 fr 16 42 fr6 17 fr 20 50 fr

The resista nce coefficient, K/I, for pipe bends otherthan qoo may he determined as follows:

[ 11= 11 - I) 0.25 7r fr J+ 0.5 K + I

n = number ofquo

bt:nds= rt:sistunec coefficient for one l}O° ocnd (per tuble)

-- , ----- , ---------- , -- ,CLOSE PATTERN RETURN BENDS

STANDARD ELBOWS

90°

~I

K = 30 iT I = l T

STANDARD TEES

. J - L

low thru run = 2 0 T

FIO\\ t hru branch I = 60 T

InwardProjecting

PIPE ENTRANCE

rid

0.00* 0.50.02 0.280.04 0.240.06 0.150.10 0.09

0.15 & up 0.04Sharp-edged

Flush

For I<,see table

------------------._--------.---Projecting

K = 1.0

PIPE EXI r

Sharp-Edged Rounded

I

---K = 1 0

Download - Coeficientes de Perdidas Locales en Accesorios CRANE

Top Related