UNITE DE POMPAGE A BALANCIER COURBE

CURVED-BEAM PUMPING UNIT

Abrégé français

Unité de pompage à balancier incurvé, comprenant un support et un réducteur de vitesse fixés à une base, une assise de poutre est montée à l'une des extrémités supérieures du support, et un système de coupleur est relié à une extrémité de la traverse et fixé au balancier, et relié à une manivelle à l'autre extrémité, reliant le réducteur de vitesse au poids d'équilibrage de la manivelle, caractérisé par le fait que l'extrémité arrière du balancier est incurvée et que son contrepoids se trouve au niveau de la queue.

Abrégé anglais

A curved-beam pumping unit is provided, in which a support and a speed reducer are both affixed to a base, a beam seat is mounted on an upper end of the support, and a coupler assembly is connected at one end to a crossbeam fixed on a walking beam and connected at the other end to a crank which connecting the speed reducer with a crank balance, characterized in that the rear end of the walking beam is formed as curved shape and having a balance weight mounted on its tail part.

Revendications

Claims
1. A curved-beam pumping unit, in which a support and a speed reducer
are both affixed to a base, a beam seat is mounted on an upper end of the
support, and a coupler assembly is connected at one end to a crossbeam fixed
on
a walking beam and connected at the other end to a crank which connecting the
speed reducer with a crank balance, characterized in that the rear end of the
walking beam is formed as curved shape and having a balance weight mounted
on its tail part.
2. The curved-beam pumping unit as claimed in claim 1, wherein the
number and position of the balance weight mounted on the rear end of the
walking beam are adjustable.
3. The curved-beam pumping unit as claimed in claim 1, wherein the beam
seat is installed diametrically at the fulcrums on an upper, lower or middle
part of the walking beam.
4. The curved-beam pumping unit as claimed in claim 1, wherein the
walking beam is formed as staggered or zigzag shape.
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Description

CA 02322407 2000-10-OS
Curved-beam Pumping Unit
The present invention relates to a pumping apparatus for oil production.
This apparatus belongs to a kind of curved-beam pumping unit.
At present, for non-flowing oil wells, it is generally exploited with
mechanical pumping units, such as the most widely used curved-beam pumping
units. In a curved-beam pumping unit, a walking beam is pivotally supported
on a support via a beam seat, a horsehead is installed on a front end of the
walking beam and connected with a pumping rod though a cable suspension, a
rear end of walking beam is pivoted on a crank and coupler mechanism by a
crossbeam, and a motor drives the crank and coupler mechanism via a speed
reducer. The walking beam is driven by the crank and coupler mechanisms
through the crossbeam, to swings reciprocally in a vertical plane. Therefore,
the
horsehead and the cable suspension can drive the pumping rod moving up and
down reciprocally, to pumping oil. The walking beam type pumping unit has the
advantages of working reliably, being sturdy and durable, easy to maintain,
and
working in open fields perennially without inspected especially. However, in
the
past more than 100 years, walking beam type pumping units have been affected
by the four-bar linkage, so that the load acting on the crank which is
resulted
from the load at suspension point of pumping unit does not vary sinuously.
Furthermore, being affected by additional loads during operating, including
the
inertial load at suspension point, the loading torque curve would deform.
Therefore, the crank balancing torque, which varies sinuously, could not
balance
with the load torque. In addition, the net output torque of the crank in one
turn
would arises a relatively high peak value and a relatively low valley
(negative)
value, so that the energy consumption of the pumping unit is increased and the
efficiency of the pumping unit is decreased. Meanwhile, the lifetime of the
speed reducer would be sacrificed from the negative torque.
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CA 02322407 2000-10-OS
With the development of oil wells, the liquid level of oil well lowers
gradually, the number of flowing wells decreases progressively, and more and
more pumping units are put into use. As a result, the problems about long
stroking and deep pumping, the increasing of efficiency of pumping unit, and
the lowering of energy consumption, etc., appear to be more significant.
It is an object of the present invention to provide a curved-beam pumping
unit which can avoid the disadvantages in the prior art, and to provide an
energy-economized pumping unit with long stroke, low energy consumption and
high efficiency, and being sturdy and durable and easy to operate.
The above object has been obtained by a curved-beam pumping unit, in
which a support and a speed reducer are both affixed to a base, a beam seat is
mounted on an upper end of the support, and a coupler assembly is connected at
one end to a crossbeam fixed on a walking beam and connected at the other end
to a crank which connecting the speed reducer with a crank balance,
characterized in that the rear end of the walking beam is formed as curved
shape
and having a balance weight mounted on its tail part.
The number and position of the balance weight mounted on the rear end of
the walking beam are adjustable.
The beam seat may be installed diametrically at the fulcrums on the upper,
lower or middle part of the walking beam, and the walking beam may be formed
as staggered or zigzag shape.
The present invention has the advantages as follows:
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CA 02322407 2000-10-OS
1. The balancing effect of the pumping unit is improved, and the peak and
valley values of net output torque of the crank are decreased.
2. The stress of four-bar linkage is reduced, the swing angle increased, a
long stroke can be obtained, the reliability of the components is raised, and
the
features of normal beam pumping unit, such as structural simplicity,
reliability
and durability, can be possessed.
3. The energy consumption of the pumping unit is decreased, so as to
increasing the overall efficiency.
The present invention is to be explained with exemplary embodiments and
in connection with the drawings, in which:
Fig. 1 is a schematic drawing of the structure of a curved-beam pumping
unit.
Fig. 2 is a schematic drawing of a walking beam and a beam seat of the
curved-beam pumping unit.
Fig. 3 is a schematic drawing of a walking beam and a beam seat of the
curved-beam pumping unit.
As shown in Fig. 1, a support 2 and a speed reducer 12 are both affixed to a
base 1, and a beam seat 3 is mounted on an upper end of the support 2. A
walking beam 6, which is formed as curved shape, is diametrically connected to
the beam seat 3 at an optimum fulcrum and attached to the beam seat 3. A
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CA 02322407 2000-10-OS
horsehead 5 and a suspension 4 are mounted on the front end of the walking
beam 6, a beam balance 8 is mounted on the rear end of the walking beam 6, and
a crossbeam 7 is mounted on a curved portion of the walking beam 6 by
bearings.
A coupler assembly 9 is connected at one end to the crossbeam 7, and attached
at the other end to a crank 11 which connecting a crank balance 10 and the
speed
reducer 12. When the crank and coupler mechanism is brought into operating by
the speed reducer 12, the walking beam 6 is driven by the crank 11 and the
coupler assembly 9 through the crossbeam 7, so as to move reciprocally in a
vertical plane. The suspension 4 is acted by the horsehead S, so as to move up
and down, to pumping oil.
The walking beam 6 may also be formed as staggered or zigzag shape, as
shown in Figs. 2 and 3. The beam seat 3 may also mounted on the lower or
middle part of the walking beam 6 at the optimum fulcrum.
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Dessin représentatif