Submersible pumps of oil type, which are denoted by the abbreviation SHGN, are devices, with which you can pump liquid media from wells, characterized by considerable depth. The use of such pumping equipment is one of the most popular ways to pump oil: about 70% Today's oil wells are serviced by rod pumps.
Oil well, equipped with a rod submersible pump
Design features and principle of operation
The main design elements of the oil pump, which is placed in the well on a special column, consisting of risers, is:
- cylindrical body, in the inner part of which a hollow piston is installed (displacer), called a plunger;
- discharge valve, which is installed at the top of the displacer;
- suction ball valve, which is located in the lower part of the fixed cylindrical body;
- pump rods, connected to a special mechanism (swing) and plunger and report to the latter reciprocating motion (the swing itself, which drives the downhole rod pump (СШН), mounted outside the well - on the ground).
Oil submersible pump device
The principle of operation of deep rod pumps is quite simple.
- When you move the plunger up in the lower part of the pump chamber creates a pressure vacuum, which promotes the suction of the pumped liquid medium through the inlet valve.
- When the plunger starts moving down, the suction valve closes under the pressure of the pumped liquid medium, and it through the hollow channel of the piston and the discharge valve begins to enter the risers.
- During continuous operation of the rod submersible pump, the liquid medium pumped by it begins to fill the internal volume of the riser pipes and is eventually sent to the surface..
The principle of operation of SHGN
The main varieties
According to their design, rod submersible pumps can be:
- plug-in;
- non-insertable.
Lowering of plug-in submersible submersible pumps into the well, as well as their removal from it, carried out in assembled form. To perform such an operation, the plunger is placed inside the cylinder, and the whole structure on the pump rods is lowered into the mine.
Types of SHGN pumps by the method of attachment to the column
Plug-in SHGN are also divided into two types of devices:
- plug-in pumps with the upper location of the lock (HB1);
- pumps, the lock of which is located in their lower part (HB2).
Inserts are used mainly for servicing deep wells, characterized also by a small flow rate of the liquid medium pumped out of them. Use of such SHN pumps, to obtain which it is enough to lift the rods, to which the entire pump design is connected, greatly simplifies well repair, if necessary.
The scheme of operation of the installation with SHGN
In order to place a non-plug-in submersible rod submersible pump in the well, more complex actions need to be performed. The cylinder is first placed in the well, for which tubing is used, and only then, using bars, the piston with valves is lowered into the already installed cylinder. Extraction of the oil submersible pump of this type is also carried out in two steps: first of all the plunger with valves is removed from the cylinder of the pump, and then a cylinder with tubing rises from the well.
Non-plug-in devices are also divided into several categories:
- pump installations without a catcher (NN);
- non-plug-in submersible pumps with gripping rod (НН1);
- non-insert pumps with trap (НН2).
Submersible drainage sump pumps are available in various sizes and designs, including special orders for work in special conditions
Among the above types of non-plug-in equipment, the most popular devices, equipped with a catcher (НН2). The high popularity of the latter is explained, that the mechanism of their emptying is simple and, in accordance, greater reliability in operation.
The choice of equipment of a particular model is made depending on the specific operating conditions, as well as the characteristics of the liquid medium, which is planned to be pumped out with its help.
Downhole rod pump version НН2Б
How to read labels
To determine, to which category the submersible rod pump belongs, as well as learn, what are the characteristics of such a device, it is enough to decipher its marking. Such marking, deciphering which is not difficult, looks as follows:
XXX X - XX - XX - XX - X
Letters and numbers, present in such markings, consistently indicate the following parameters:
- sucker rod pump type, which, as mentioned above, may fall into one of the following categories: HB1, HB2, NN, HH1, НН2;
- the type of design of the cylinder and design features of the device as a whole;
- conditional diameter of the plunger, measured in mm (modern models of rod submersible pumps on this parameter can belong to the devices of the following categories: 29, 32, 38, 44, 57, 70, 95 and 102 mm);
- maximum stroke, which can carry a plunger (to find out, at what distance in mm the plunger moves, the value in the label must be divided by one hundred);
- onslaught in meters of water. Art., which is able to provide the presented submersible pump (this value in the label must also be divided by one hundred);
- landing group (by the degree of increase in distance, available between the plunger and the inner walls of the cylinder, the devices under consideration may correspond to one of the following landing groups: 0, 1, 2, 3).
Groups of landings of the pump depending on the size of a backlash between the cylinder and the plunger
structural elements
The efficiency and effectiveness of the use of submersible oil pumps determine the following elements, present in their design:
- cylinders, which may be integral or integral;
- plungers (ordinary or sandblasted type);
- ball-type valve assemblies, locking elements which are the saddle and the ball;
- anchor boots, which are used for fastening in tubing tubes of rod submersible submersible pumps (when installing such elements it is necessary to ensure the sealing of the suction cavity of the pump from the discharge).
Of course, The obligatory element of a design of the rod submersible pump is a rod - the round core made of steel with the landed ends. The main purpose of the rods, which may have different diameters (12, 16, 18, 22 and 25 mm), is, to inform the plunger reciprocating motion.
Pump rod and coupling
Because during the operation of the submersible pump, the rods experience serious loads, high-quality steels are used for their production, and after manufacturing are subjected to normalization annealing and hardening of HDTV.
Rod pumping devices depending on design features of the plunger and the cylinder, as well as from that, how their anchor shoe is located, may belong to one of 15 categories.
The photo shows a ball-type suction valve, placed in a cylindrical housing
Advantages and disadvantages
Submersible drainage sump pumps have a number of advantages over other pumping devices:
- high value of efficiency;
- the possibility of maintenance and repair in the field;
- use of different types of engines;
- possibility of use for service of sand-developing wells, as well as for pumping oil, which has a gas component and a large amount of petroleum wax.
As with any other technical device, There are disadvantages of rod pumps:
- restrictions on the depth of wells, for the maintenance of which they can be used (the risk of breaking the rods is higher, the deeper the well, in which the pump goes down);
- low feed value, provided by these pumps;
- impossibility of application for maintenance of wells, characterized by a significant slope and curvature of the mine;
- impossibility of pumping with the help of such deep pumps of liquid medium from wells of horizontal type.
And finally, a short video on the installation and operation of rod submersible pumps.