Slotted downhole filters Slide (SDF)

Field of application

Advantages

• Sustained full-cycle throughput with self-purification capability.
• Stable operation of downhole pumping equipment due to increased filtration surface.
• Low clogging of the filtering element due to the unstable position of mechanical particles on the filtering surface and the cleanliness of the wedge profile surface.
• High axial and radial structural capability (up to 1,918 lbsfft) due to the increased number of bearing elements.
• High corrosion resistance and resistance to aggressive action of acidalkali agents.

Principle of operation

• The fluid coming to the pump intake from the well is purified from mechanical particles, passing through the filter element made of stainless-steel wedge profile of AISI 304, AISI 316 grade, which is spirally wound with a certain pitch on bearing elements to provide a rigid screen with longitudinal slots of strictly defined clearance. Sharp edges create an arch (sand bridge) over certain slot sections, thus maintaining the permeability over these sections.
• In the lower part of the filter, in the filter housing recess, there is a spool piece, which comes into operation in case of total clogging of the filter element. Due to the pressure difference inside the filter housing and in the plug under the spool piece, the spool piece moves upward until the hole is aligned with the slot in the spool piece. The reciprocation of the spool piece, caused by the movement of the produced fluid, ensures the filter self-purification of foreign matter.