STANDARD HANDBOOK OF PETROLEUM & NATURAL GAS ...

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CASE "0"
s-3
Drum
Hoisting System 587
CA S E "E"
Single Drum
Double Drum with Equalizer
L Load; S:NO. of Sheaves; N: No. of Rope Parts Supporting Load
(Not counting equalizer)
FAST LINE TENSION = FAST LINE FACTOR X LOAD
1 2 3 4 5 6 7 8 9
Plain Bearing Sheaves
Roller Bearing Sheaves
K = 1.09.' K = 1.04.
y r
Efficiency Fast Line Factor Efficiency Fast Line Factor
N CaseD CpseE CaseD CasoE CoseD CaseE CmeD CaseE
2 ,959 1 .Ooo .522 .500 981 1.000 ,510 .m
3 .920 .... ,362 .... .962 .... 2.46 ....
4 .a83 .959 283 ,261 944 .sa1 ,265 ,255
5 .848 .... 936 .... .926 .... 216 ....
6 ,815 .920 .204 .181 .909 2x2 ,183 ,173
7 ,784 .... .182 .... .892 .... ,160 ....
8 ,754 .883 ,166 ,141 A75 ,944 .143 ,132
9
,726 .... .153 .... ,859 .... .130 ....
10 ,700 ,848 .143 .118 .844 .926 .119 .IO8
11 ,674 .... .135 .... .828 .... .110 ....
12 ,650 ,815 .128 ,102 ,813 .909 .lo1 ,091
13 528 .... .122 .... ,799 .... .096 ....
14 .606 .784 .118 ,091 ,785 .a92 .os1 ,080
15 -586 .... .114 .... .771 .... .OS6 ....
CASE 'D EFFICIENCY
FAST LlNE FACTOR =
KSN (K-1)
1
N x EFFICIENCY
'UK? -1)
CASE "E EFFIClENCY =
K S N (K-1)
1
FAST LINE FACTOR =
N x EFFlClENCY
NOTE: The W e ases apPl9 also where the mp h dead ended or the equalizer is bated at the
lower or traveling block or derrick flmr after passing mer a dead shave in the mown.
*In theae tables. the K factor for sheave friction ii 1.09 for lain bearings and 1.04 for roller
bearinpn. Olher K factors can be used if recommended by the equipment manufacturer.
Figure 4-69. Efficiency of wire-rope reeving for multiple sheave biocks,
Cases D and E [ll].
2. Rotary drilling lines. Care should be taken to maintain proper winding of
rotary drilling lines on the drawworks drum to avoid excessive friction that
may result in the formation of martensite. Martensite may also be formed by
excessive friction in worn grooves of sheaves, slippage in sheaves, or excessive
friction resulting from rubbing against a derrick member. A line guide