Senin, 04 Maret 2013

casing

     
I.            Function of Casing
Following are the important function of casing.
  •   To prevent the caving of hole
  •   To prevent  contamination of fresh  water in upper sand
  •   To exclude watter from the producting formation
  •   To confine production to well bore
  •   To provide means of controlling pressures
  •   To facilitate installation of subsurface equipment
II.            Classification of casing
       the classification of casing is bassed on primary function of the casing string. there are four types of casing :
            a. conductor casing 
            b. surface casing
     c. intermediate casing
     d. production casing
        

                                                                                             
Production casing
      A.   Conductor Casing
  •   Diameter 16-48 inci
  •   Digunakan di offshore / di kondisi extra
  •   Kedalaman sampai 100-400 feet
  •   Ukuran lingkaran general dari 8 5/8 hingga 20 inci OD (out side Diameter)
  •   Mencegah underground blow out
B.      Intermediate Casing
  •   Ukuran lingkaran general dari 7 5/8 -13 3/8 inci OD (out side diameter)
  •   Untuk kedalaman 3000 s/d 8000 feet
  •   Fungsi = mengisolasi formasi yang lunak, supaya pemboran bisa di perdalam
C.      Production Casing
  •   Ukuran 4 ½ - 9 5/8 inci OD (out side diameter)
  •   Casing paling bawah
  •   Di pasang sampai zona produksi
D.      Production Tubing
  •   Berada di dalam pipa
  •   Ukuran 1 – 2 inci OD (out side diameter)