Bài giảng Well drilling engineering - Chapter 9: Directional drilling - Đỗ Quang Khánh

1 Well Drilling Engineering  Directional Drilling Dr. DO QUANG KHANH 2 Directional Drilling When is it used? Type I Wells Type II Wells Type III Wells Directional Well Planning & Design Survey Calculation Methods I II III 3 Read ADE Ch.8 (Reference) 4 Inclination Angle q, a , I Direction Angle f, e , A 5 6 Max. Horiz. Depart. ? 7 8 9 10 11 12 Type I Type II Type III 13 D x D y I I r r D L 14 15 Fig. 8.11 16 17 N18E N55W S20W S23E Azimuth Angle 18 19 Example 1: Design of Directional Well Design a directional well with the following restrictions: Total horizontal departure = 4,500 ft True vertical depth (TVD) = 12,500 ft Depth to kickoff point (KOP) = 2,500 ft Rate of build of hole angle = 1.5 deg/100 ft Type I well (build and hold) 20 Example 1: Design of Directional Well (i) What is the maximum hole angle required. (ii) What is the total measured depth (MD)? (MD = well depth measured along the wellbore, not the vertical depth ) 21 * The actual well path hardly ever coincides with the planned trajectory * Important: Hit target within specified radius 22 What is known? I 1 , I 2 , A 1 , A 2 , D L = D MD 1-2 Calculate b = dogleg angle DLS = b*100/D L DLS = dogleg severity 23 24 (20)