Drilling Homework help

[cayita095]

Hi, I'm taking an introductory course on drilling and I'm stuck on some of the problems, I was wondering if anyone could help me with them. Thanks!

• Calculate the minimum time required to reel a 20,000 ft. cable weighing 1 lbf/ft to the surface using a 25 hp engine

• A drawworks drum has a diameter of 45 in., a width of 87.5 in., and contains 1.75 - in. drilling line. Calculate the approximate length of line to the first lap point
• Compute the tension in the fastline when lifting a 750,000 lbf load for 6, 8, 10, and 12 lines strung between the crown block and the traveling block

The following data are obtained on a gasoline engine:
Engine Speed, rpm
500
1,000
1,500
2,000

Torque, ft-lbf
2,000
1,850
1,700
1,550

Fuel Consumption Rate,gal /hr
10.1
16.7
22.3
26.8
a)Calculate the break HP at each engine speed.
b) Calculate the overall engine efficiency at each engine speed.
c)Calculate the fuel consumption in gallons per day for an average speed of 1000 rpm and a 12-hour work day

ps. the data goes together it just dont let me out it in a table here

Thanks again!

[rcer]

Calculate the minimum time required to reel a 20,000 ft. cable weighing 1 lbf/ft to the surface using a 25 hp engine
F = average weight to lift = (20000+1)/2=10000.5 lbs
S = 20000 ft
t=FxS/(550xhp) = 10000.5x20000/(550x25)= 14546 seconds or 242 minutes

A drawworks drum has a diameter of 45 in., a width of 87.5 in., and contains 1.75 - in. drilling line. Calculate the approximate length of line to the first lap point
First layer:
L1 = Phi/12(D+d)W/d (ft)
L1= 3.14/12(45+1.75)87.5/1.75= 612 ft

Compute the tension in the fastline when lifting a 750,000 lbf load for 6, 8, 10, and 12 lines strung between the crown block and the traveling block
Ff = Fh/(E*n)
Ff = fast line load
Fh= hook load
E = reeving efficiency ( for roller bearings and for 6, 8, 10, and 12 lines strung; E= respectively: 0.874, 0.842, 0.811, 0.782)
n= lines strung
Ff (6 lines) = 750000/(0.874*6) = 143020 lbs

[rcer]

Calculate the minimum time required to reel a 20,000 ft. cable weighing 1 lbf/ft to the surface using a 25 hp engine
F = average weight to lift = (20000+1)/2=10000.5 lbs
S = 20000 ft
t=FxS/(550xhp) = 10000.5x20000/(550x25)= 14546 seconds or 242 minutes

A drawworks drum has a diameter of 45 in., a width of 87.5 in., and contains 1.75 - in. drilling line. Calculate the approximate length of line to the first lap point
First layer:
L1 = Phi/12(D+d)W/d (ft)
L1= 3.14/12(45+1.75)87.5/1.75= 612 ft

Compute the tension in the fastline when lifting a 750,000 lbf load for 6, 8, 10, and 12 lines strung between the crown block and the traveling block
Ff = Fh/(E*n)
Ff = fast line load
Fh= hook load
E = reeving efficiency ( for roller bearings and for 6, 8, 10, and 12 lines strung; E= respectively: 0.874, 0.842, 0.811, 0.782)
n= lines strung
Ff (6 lines) = 750000/(0.874*6) = 143020 lbs

[cayita095]

Wow! thank you so much. I'm sort of familiar with the equations but I didn't really know what to plug in where. Thanks again