US3272145A - Bore pumps - Google Patents

Description

Sept 13, 1966 G. L. TOWNER 3,272,45

Borm PUMPS Filed oct. z2, 1964 United States Patent O 3,272,145 BORE PUMPS Gresley Lukin Towner, Tooloon, Charleville, Queensland, Australia Filed Oct. 22, 1964, Ser. No. 405,768 2 Claims. (Cl. 10S-224) This invention relates to reciprocating bore pumps, whether driven by wind power or by la motor.

Bore pumps are generally operated by a long rod to the lower end of which the pump plunger is attached, the rod being reciprocated by the power source to drive the pump.

On the up-stroke the pump has to lift a column of water the depth of the bore with consequent stress on the rod and power source.

As -will be appreciated, this stress is periodic in nature and its onset is sudden on each occurrence with consequent strain and danger of breakage of the parts. This effect is accentuated by lwater hammer in the bore, caused mainly by resonance surges of pressure in the water column.

As a result, bore pumps are subject to breakdown and need constant repairs and inspections, which, particularly in remote bores, involves large expenditure.

An'object of this invention is to reduce the stresses above referred to, and therefore reduce breakdowns.

A further object is to obtain .a more even flow from the pump.

In order that the invention may be better understood, one particular embodiment will now be described by way of example with reference to the single figure of the drawings, which shows in section a bore pump according to the invention.

In general the bore is defined by a bore casing 10, in which a pump rod of jointed form reciprocates to drive a pump plunger, generally indicated at 11, up and down to lift the water in the casing on the up-stroke. Pumps of this general type are well-known.

In this embodiment of the inventi-on, the sections 12, 13, 14 of the pump rod are of special form to be described below, and are coupled between a reciprocating power source (not shown) and plunger 11.

Each section 12, 13 and 14 is formed of a hollow tube of high-strength material such as high-tensile steel or fibre-glass. A threaded socket 15 is secured in the upper part of each section and an externally threaded plug 16 in the lower part of sections 12, 13, the lower part of section 14 being open, the plugs 16 and sockets 15 being screwed together to join the sections, and a resilient washer 17 being provided to seal each joint.

Sockets 15 and plugs 16 are each provided with a t central aperture 18 leading to the interior of the section.

The aperture 18 of socket 15 in the upper section 12 is closed by =a non-return air valve 19 having means at its upper end to attach it to a compressor or air pump.

With the pump rod jointed together, there will be a continuous air space along its length, open at the bottom of section 14, and sealed by valve 19 at the top of section 12.

The lbottom of section 14 is attached by suitable means, shown as a t-ubular member 20, to the pump plunger 11.

The member 20 serves to connect section 14 mechanically to plunger 11, while providing apertures 20A, through which the water pressure within the casing 10 has access to the lower open end of the section 14 and therekfore to the total air-space within the series of sections 14, 13, 12.

A reduced diameter part 21 of member 20 passes Patented Sept. 13, 1966 ICC through an upper bucket washer 22, a spacer 23 and a lower bucket Iwasher 24 and is secured by a nut 25 thereon.

The plunger 11 as is well-understood will allow water to pass the washers 22, 24 on the down-stroke but not on the up-stroke. The air space within the pump rod acts as a shock absorber, for sudden changes of water pressure whether caused by the reciprocation of plunger 11 or by water hammer.

In use, the plunger 11 or its pump rod is lowered down casing 10 and, as the `water head increases, the air in the interior of the rod is compressed, water therefore rising some distance into the air space. As the pressure of W-ater changes on reciprocation of plunger 11, the volume of air changes inversely and pressure shocks are minimized.

The practical effect of this cushioning is to reduce stresses on the working parts of the pump and prevent water hammer, so making for much longer life of the pump.

The narrower parts of the air space, such as the apertures 18 tend to slow down the movement of air or water within the pump rod and further resist sud-den changes of pressure.

In addition, it is found that with the air space the flow from the pump is almost constant instead of being of intermittent or stop-start type as in prior pumps.

After long use, the air is found to be gradually reduced by solution in the water. The air-space may be re-charged by passing air from an air-pump or compressor through the non-return valve 19 into the air-space.

Similarly for deeper bores, it is an advantage to increase lthe pressure of air in the space, and this again may be achieved via valve 19.

For shallower bores, up to 40 `or 50 feet deep, it is possible to -make the pump r-od of a single section of t-ubular form with a non-return valve equivalent to valve 19 at its upper end and apertures equivalent to apertures 20A in its lower side Walls. Such `a construction gives the advantages of the arrangement illustrated with a much simpler and cheaper construction. The only effect not attained is the damping effect of the constructions 18 in the -air space, and such effect is of little importance for shallow bores.

It is comparatively simple to convert a standard bore arrangement to incorporate the invention. All that is needed is to remove the usual pump rod and substitute a hollow rod and apertured tubular member 20, or an equivalent hollow rod arrangement and a valve 19. The plunger 11, casing 10 and means (not shown) for reciprocating the rod may be of prior known type.

It has been found that the effectiveness of the air-space appears to be greater -with the apertures 20A situated immediately above the plunger 11, rather than at some distance from said plunger.

It is pointed out that the air chamber in deep well pumps, for which the present invention is particularly suitable, to be properly effective, must be pressurized and this pressurization must be available in situ. According t-o the present invention this is accomplished by (l) providing an air chamber extending to the surface `within the pump rod, and (2) locating the recharging valve at the accessible upper end of the chamber.

Various other modifications and changes may be made in the equipment described without departing from the invention as defined by the claims.

What I claim is:

1. A reciprocating bore pump having a casing, a pump plunger within said casing, a hollow pump rod for reciprocating said plunger, the interior of said rod forming an air chamber open to the water pressure immediately References Cited by the Examiner UNITED STATES PATENTS 297,076 4/1884 Hardie 103-224 X 334,211 1/1886 Babcox 103-224 X 336,039 2/1886 Darnell 103-224 X 2,594,833 4/ 1952 White 103-224 ROBERT M. WALKER, Primary Examiner.

Claims (1)

1. A RECIPROCATING BORE PUMP HAVING A CASING, A PUMP PLUNGER WITHIN SAID CASING, A HOLLOW PUMP ROD FOR RECIPROCATING SAID PLUNGER, THE INTERIOR OF SAID ROD FORMING AN AIR CHAMBER OPEN TO THE WATER PRESSURE IMMEDIATELY ABOVE SAID PLUNGER AND EXTENDING CONTINUOUSLY TO THE SURFACE OF SAID BORE, A NON-RETURN AIR VALVE CLOSING THE UPPER END OF SAID CHAMBER AND MEANS FOR ATTACHING A SOURCE OF COMPRESSED AIR TO SAID VALVE TO RECHARGE SAID CHAMBER,

Images