Three-Tube Pump

This type of pump is illustrated in Fig. 8.8 and gets its name from the three tubes used in its construction. Technical Data used in the field explained in petroleum courses in Rawalpindi. The complete pump assembly is lowered into the well on the sucker-rod string and is positioned in the well by contacting either a cup-seating assembly or a mechanical lock hold down.

 The middle tube of the pump is stationary, attached to the hold down. The other two tubes attached to the sucker-rod string move over the middle stationary  tube, one on the outside and one on the inside. The tubes used in this pump are relatively long and have a relatively large operating clearance in comparison with the usual pump plunger. The resistance to flow between the tubes is adequate to create the seal necessary to displace the fluid past the standing valve and through the traveling valve against the tubing pressure. Some more details of petroleum courses in rawalpindi are as under.

This pump is designed primarily to clean out wells after work over operations or formation-fracturing operations, which may make the well produce large quantities of sand for a considerable time. It is also used in wells producing from loose-sand formations that consistently produce quantities of fine floating sand.

Where conditions are such that there is considerable free gas in the well fluid at the pump intake, it is desirable to prevent as much gas as possible from entering the pump and permit the gas to rise to the surface through the casing annulus rather than through the tubing. Numerous so-called gas anchors are in use that are designed to separate the free gas and deflect it up the casing annulus.

Fig. 8.9 illustrates a common type of gas-anchor arrangement in which the well fluid must enter the perforated nipple and circulate downward at a low velocity before entering the gas-anchor tube, which is attached to the pump intake. This gives the free gas an opportunity to separate and rise to the uppermost ports in the perforated nipple where it may return to the casing. A large portion of the gas will rise through the casing before passing through the perforated nipple. TSK Training for Skills and Knowledge is the best institute in Rawalpindi Islamabad for Pakistani Students who wants to join oil field after petroleum courses in rawalpindi