BAKER HUGHES - Drilling Fluids Reference Manual

HYDRAULICS
4. Calculate hydraulic horsepower and impact force.
QP (
HHP n )
-------------- = ( 375
------------------------------ ) 1799
= - ( ) = 394 hp
1714 1714
1.2732
--------------------------------- ( )( 394
HHP/in. 2 1.2732
= ( )HHP
= ---------------------------------- ) = 5.14 hp/in. 2
D 2 ( 9.875) 2
F ( 15.3) ( 375) 363
i = ------------------------------------------- ( ) = 1078 lb
1932
f
5. Calculate total nozzle area to maximize HHP or Impact Force. For maximum HHP, C = 0.65.
A t
= -------------------------------------------------------------
Q
2.96 ( 1238.5 )( C ) ( P
--------------------------------------- ) 1/2
ρ
For maximum impact, C = 0.48
=
-------------------------------------------------------------------------
375
2.96 ( 1238.5
= 0.2952 i n. 2
)(.65) ( 3500
------------------------------------------------- ) 1/2
15.3
6. Select jet sizes.
375
A t = -------------------------------------------------------------------------
2.96 ( 1238.5
= 0.3435 in. 2
-------------------------------------------------- )(.48) ( 3500 ) 1/2
15.3
For 3 jets, N = 3; maximum HHP
1
1303.797
⁄ 2
1
1303.797
⁄ 2
J 1 = ---------------------A
N t = ---------------------0.2952 ( ) = 11 .3 → 11
3
⎛
2
1303.797
( J
------------------ A 1
)
1/2 ⎜ t
– -----------------
N – 1 ⎜ 1303.797⎟ ⎟⎞ = ------------------ 1303.797
3 – 1
0 .295 2 – -----------------
11 2
⎝
⎛ 1303.797⎠
⎞ 1/2 = 11.49 → 11
⎝
⎠
2
⎛
1303.797
( J
---------------- A 1
) + ( J 2
) 2 ⎞ 1/2
⎜ – -------------------------⎟
1303.797
N – 2 ⎜ t 1303.797 ⎟
---------------- ⎛
3 – 2
0.2 952 –
11
----- 2 ---
+
--------
11 2
-⎞ 1/2 =
= 11.59 → 12
⎝ 1303.797 ⎠
⎝
⎠
J 2 =
J 3
=
For jets, N = 2; maximum HHP
J 1
Therefore, for maximum HHP with 3500 psi on the standpipe, we would choose 3 jets of 11, 11, and
12.
J
2
=
=
1/2
1303.797 1303.797
---------------------A t = --------------------- ( 0.2952 ) 1/2 = 13.87 → 14
N
2
2
(J 1 )
t ---------------------
N–
1 ⎝
⎜ 1303.797⎠
⎟ ⎞ 1/2
1303.797⎛
--------------------- A –
=
1303.797 --------------------- ⎛
2–
1
A – ---------------------
142
⎞ 1/2 = 13.74 14
⎝ t 1303.797⎠
→
Therefore, for maximum HHP with 3500 psi on the standpipe, we would choose 2 jets of 14 and
14.
BAKER HUGHES DRILLING FLUIDS
REFERENCE MANUAL
REVISION 2006 9-35