Question

2. The weight of a rotary drilling bit on the formation is usually kept in the range of 200 pounds. If a well is being drilled using standard pipe, 2-7/8 inches OD and 2.1 inches ID, what is the weight of the 10,000 ft of pipe, and hence how much load does the rotary drill rig have to hold in order to limit the drill pressure on the formation to 200 pounds.

Answer 1

answer-

A).

w_p = ρ_m A_m

    = ρ_m π (d_o² - d_i²) / 4

= (π / 4) ρ_m (d_o² - d_i²)      (4)

where

w_p = weight of empty pipe per unit length (kg/m, lb/in)

ρ_m = density of pipe material (kg/m³, lb/in³)

A_m = cross-sectional wall area of pipe (m², in²)

d_o = outside diameter (m, in)

d_i = d_o - 2 t = inside diameter (m, in)

t = wall thickness (m, in)

so using the formula the weight of 10000 ft. of pipe is 1070 kg.

The load that the rotary drill rig is 5.33