casing design - theory and practice

[...]... weight 1lTt, is fxpressed as: lVt, = 1 { ( Upr [2O - ( L , ?.J)/?JJ \\.eight of coupliiig 20 Weight removed in threading two pipe endh } - ~ where: + + ( 13 ) 14 F-e+' ~~ENTER O F ~ ' I-~ , L 4 - - - - I' = Lc -~ +d ? q -7 COUPLING 7 L2 - C~ N _( ~ E R ~ TRIANGLE STAMP E7 L r- A1 - - - - - - Lc L1 P I P E END TO HAND TIGHT PLANE E1 PITCH DIAMETER AT HAND TIGHT PLANE L2 MINIMUM LENGTH, FULL CRESTED... for ljc = 21, 30 and 40 - assumed average lengths of R1 R2 and R3 casing available Solution: For a casing complete with couplings, the length lj,: is the distance measured fronl the uncoupled end of the pipe to the outer face of the coupling at the opposite end, with the coupling made-up power-tight (API Spec 5CT) 3 From Table 1.4, L c - 7a in and J - 0.500-in Thus, Ll = = @- J 3.87 5- 0.500 3.375 in... t h r casing w i t h coupliiig L , = length of t h e coupling 11 L~ 2 d lj - - length of pipe "1 ILl L Ij , t lj= = length of casing with coupling d - distance between end of casing in power tight position and the center of the coupling L l = makeup loss Lc = length of the coupling Fig 1.5" Makeup loss per joint of casing J - Ll - distance between the casing end in the power tight position and the... COMPUTER AIDED CASING DESIGN 5.1 ‘2X 259 OPTIMIZING T H E COST OF T H E CASING DESIGS 25!) 5.1.1 Concept of the Minimum Cost Combination Casing String ‘260 5.1.2 Graphical Approach to Casing Design: Quick Design Charts 261 5.1.3 Casing Design Optimization in Vertical b’ells 5.1.4 General Theory of Casing optimization 286 5.1.5 Casing Cost Optimization in Directional... ft from the casing shoe and hung onto the surface casing Longer cement columns are sometimes necessary to prevent casing buckling 1.2.5 P r o d u c t i o n Casing Production casing is set through the prospective productive zones except in the case of open-hole completions It is usually designed to hold the maximal shut-in pressure of the producing formations and may be designed to withstand stimulating... drift m a n d r e l s Casing and liner Length Diameter (ID) (in.) (in.) (After (in.) 5 G 8~ 5 3 9g - 13g 6 12 ID ID > 16 12 ID 1 8 5 32 3 16 The difference between the inside diaineter and the drift diameter can be explained by considering a 7-in., 20 lb/ft casing, with a wall thickness, t, of 0.272-in Inside diameter - = - 2t 7 - 0.544 6.4,56 in OD 10 Drift diameter = = ID - G.4SG 0.125 = 6.331 in... 2.i , -. - CEMENT SURFACE CASING g , + r al PRODUCTION CASING PRODUCTION TUBING INTERMEDIATE CASING iiiiiiiii:i i LINER :.:.:.:.:.:.:.:.: :':' :-: ~R ES E RVOIR~Z-:'Z'Z' :-. v.'.' "~.":: 9 v.v.".v.'Z"Z" (O) HYDRO-PRESSURED WELLS v:.v:.'~ ~,.'.,.o.'.'.'.'.'.'.'.' 9 ~: :-: ::::::::::::: %~176176176 ~ o .~176176176 ~176 ~ " '.'.'.'.'.'.'.'.'.'.'.'.'." (b) GEO-PRESSURED... 1.6: Strengths of API steel grades ( A P I Spec 5CT, 1992.) API Grade H-40 J-55 K-5.i Yield Strength (Psi) Minimum hlaxiniurn 40,000 80:000 55,OO0 80,000 55,000 80,000 80,000 L-80 N-80 80,000 C-90 C-95 T-95 P-110 Q-125 90,000 95,000 95,000 110,000 125,000 * 1.4 95,000 110,000 105,000 110.000 110,000 110.000 150.000 Mini I nu 111 I-It ima t e Tensile Strength (psi) 60,000 75.000 95.000 95,000 100.000... cent for a test specimen with an area 2 0.7.5 in' CASING COUPLINGS AND THREAD ELEMENTS X coupling is a short piece of pipe used to ronnert the two end\ pin a i i d Ixm of the casing Casing couplings are designed to \ustitin high ten+ load wliilp 16 Table 1.7: Strengths of non-API steel grades hlinimal 1 t imat c 1 Non-AP I Grade S-80 Mod N-80 c-90 ss-95 Manufacturer Lone Star Steel hlannesmann 1,laiinesinann... (in.) (in.) 1 1 "0 5 - 3 7 4-5 1 32 q-~ 1 5 5 ~ - 8g ~9g q 3 32 "7 5 0.75 ~ OD 1 t s 0.75 ~2~ OD 5 0.75 ~ OD } 32 casing pipes are found to be within -1 -0 .75 % of the tolerance and are slightly oversized Inside diameter (ID) is specified in terms of wall thickness and drift diameter The maximal inside diameter is, therefore, controlled by the combined tolerances for the outside diameter and the wall thickness . fuiidarrieiitals of casing design and is intended as an introduction to casing design. Chapter 2 describes the casing loads experienced during drilling and running casing and in- cludes the. Combination Casing String ‘260 5.1.2 Graphical Approach to Casing Design: Quick Design Charts 261 5.1.3 Casing Design Optimization in Vertical b’ells 261 5.1.4 General Theory of Casing optimization. open-hole completions. It is usually designed to hold the maximal shut-in pressure of the producing formations and may be designed to withstand stim- ulating pressures during completion and