New designed BPE keystone slotted liner

The straight slot is the first basic type of slot manufactured. It has straight sides, equal width throughout the wall of the casing, and is more easily clogged by sand grains from the formation. As more and more slots became plugged with sand, a decreasing quantity of oil is obtained until finally a fraction of the oil available is produced. So the keystone slot is designed.

The angle of the keystone slot is usual 6⁰--15^0.

Trapezoidal cross-section of the seam is an isosceles trapezoid opening, which outer surface of the pipe is narrower than that of inner surface. Keystone seam has a strong "self-cleaning" effect, after the grit chamber into the seam; it is easy to be swept away by the oil, and not easy to form a sand plug. The pressure between tube inside and outside drops, could raise high oil recovery efficiency and good prevent-sand effect.

Keystone slotted liner has superior performance than the straight slotted liner, which can greatly improve the oil recovery rate and the daily output, greatly reducing the risk of clogging the screen. Also wide application in water wells, coal flotation, chemical and paper filters, textile and other industries.

Keystone slotted liner Features:

1. keystone slot (outer narrow, inner wide) with good self-cleaning function;

2. High-precision, slit width ≧ 0.1mm, tolerance ± 0.03mm;

3. High strength, seam-cavity surface-hardened layer of corrosion is about 0.1-0.2mm, triple strength than the base tube;

4. The slot is smooth, surface roughness is low, up to Ra1.6um;

5. Good sand prevent effect, cost-effective.