Abstract: An improved particulate separator is made from a strainer mandrel disposed in a velocity tube. The velocity tube and strainer mandrel are hollow and tubularly shaped and positioned concentrically such that a small radial distance is left open between the interior of the velocity tube and the exterior of the strainer mandrel to create an annular, vertical fluid flow region. The velocity tube and the strainer mandrel are attached to each other at their respective top ends by a solid plug means that prohibits fluid flow into or out of the top end of the annular fluid flow region. The bottom end of the strainer mandrel is plugged while the bottom end of the annular fluid flow region is left open to create the main fluid flow inlet to the particulate separator. The preferred velocity tube is a unitary hollow cylinder with a substantially solid wall while the strainer mandrel is preferably a helical tension spring.

Abstract: A sand separator is used in a well from which particulate bearing liquids are extracted into tubing for transport up the tubing. The separator causes the fluid bearing particulate matter to be accelerated. This acceleration in turn causes the particulate matter to separate from the fluid because of the higher mass and greater inertia of the particulate matter. The fluid, after separation of the particulate matter, is drawn up through the pump. The particulates preferably accumulate within a sand trap which can be pulled from the well and emptied as desired. In the case wherein the particulate matter tends to float within the liquid part of the mixture, a strainer is added after the initial inertia separation of particles from the liquid. The strainer prevents the passage of particulate matter which would tend otherwise to float upward into the output port by which the liquid passes up the tube.