Perforated liner is a sand control screen widely used in the horizontal completion wells of SAGD and other thermal heavy oil recovery. It is made of stainless steel or galvanized steel pipes slotted with single, double line or staggered patterns. This metal tubing has excellent properties in withstanding installation loads and operation loads make it the premier choice for SAGD.
The perforating of liners are done with laser cutting process without contact operation. This process can effectively avoid undesirable factors which will cause the deformation of the base pipe. Laser cutting process uses windows interface for easy operation and accurate calculation.
Perforated liner geometry consists of stamped length, stamped width, line density and perforating distribution. All these parameters can be bespoken to achieve the required open area. For example, multiple staggered pattern or gang pattern significantly increases the open area compared with single cut pattern.
Staggered perforated liner, single line patterns
Three stamped liner patterns -straight, staggered and gang - are supplied. Each has its own characteristics.
Straight line pattern | Staggered pattern | Gang pattern |
Perforated Liner Geometry
Stamped line shapes are classified into two types: straight cut slot and keystone slot. Compared with straight slot, keystone slot has higher resistance against plugging for its inter size is larger than the surface size. Once the sand entering the keystone slot, the possibility of clogging will drop sharply.
Straight cut line | Keystone slot |
Features:
Moderate cost
Ease of installation
Sufficient operation load
Non-plugging
Laser cutting process
Product specification
Required slot per ft. for 3% open area |
|||||
Slot Width (mm) |
Slot Width (inch) |
3.5" Liner |
4.5" Liner |
5.5" Liner |
7" Liner |
0.38 |
0.015 |
176 |
228 |
276 |
352 |
0.45 |
0.018 |
148 |
188 |
232 |
296 |
0.5 |
0.020 |
132 |
172 |
208 |
264 |
0.63 |
0.025 |
108 |
136 |
168 |
212 |
0.7 |
0.028 |
96 |
124 |
148 |
188 |
1 |
0.038 |
52 |
68 |
84 |
104 |
1.5 |
0.058 |
36 |
44 |
56 |
68 |
3 |
0.125 |
16 |
24 |
28 |
32 |
6 |
0.250 |
8 |
12 |
16 |
16 |
Stainless Steel Perforated Liners for Sand Control