Other Special Rod Pumps Manufacturers and Suppliers

Other Special Rod Pumps: The Complete Guide for Importers and Buyers

Sucker Rod pumps are also known as insert pumps because they are instated in the production tubing.

Pumps Nomenclature

While there are only two types of pumps systemized, there are four different sucker rod pump types.

These are classified by the type of barrel and where the pump is anchored top or bottom.

The complete pump designation of an pump adds dimensional diameters and lengths to the letter designations.

This has been modified in the latest revision to incorporate all approved sizes and barrel types and separate the extension into the top and bottom lengths if required.

The complete  designation consists of the following.

Nominal tubing size (from 1.9 to 4.5 in OD) is represented with two digits
Basic bore diameter (from 1.0625 to 3.75 in.) and is represented with three digits
Type of pump (tubing or rod) – Tor R to indicate the type
Type of barrel – heavy, thin, or X type- single alpha character to represent the barrel type
Seating-assembly location – top or bottom – A for top, B for the bottom, or T (for the bottom, traveling barrel)
Type of seating assembly – (cup or mechanical) – C or M to indicate the type
Barrel length (ft) single-digit length
Nominal plunger length- single-digit length
Length (in) of upper extension (if required) single-digit length
Length (in) of lower extension (if required)- single-digit length

It is essential to know that the users of  pumps need to provide, along with pump terminology, the following ordering information:

Barrel and plunger materials
Plunger clearance (or fit tolerance)
Valve (ball and seat) and fittings material

The Anti-Blocking Downhole Pump

The anti-blocking pump is crested and designed to correct the problem of falling objects blocking the pump

This pump has the same principle as ordinary pumps.

Moreover, it only adds the sand-fixing anti-burial standing valve, which significantly solves the sedimentation problems of tubing and rod that block the standing.

Therefore, the oil well can be produced normally, and a lot of post-production work is avoided.

It reduces the pump inspection period and thus increases the maintenance-free period.

Electric Submersible Pumps

When sucker-rod pumps and down-hole hydraulic pumps can no longer lift any sufficient fluid, electric submersible pumps are used.

These pumps consist of an electric motor, a pump, and usually some device for gas separation.

An electric conduit must be run down to power the electric motor.

Thus to accommodate a powerful electric motor and a pump, electric submersible-pump housing is large in diameter and does not have much clearance between the pump and casing.

Small deposits like sand and corrosion between the housing and pump can stick the pump not to be retrieved.

The tubing should not be pulled in two because the cable, unlike other wire lines, is flexible and quite heavy, so it should be handled carefully.

Piston Ring Type sucker rod Pump.

In a piston ring pump, a linear movement provides the required compression.

The crankshaft rotates and pushes the connecting rod with the piston back and forth.

The piston rings seal the compression space and hence allowing the compression to take place.

At very high pressure beyond 1500 bar, a high-quality finish of the piston ring plays a crucial role.

The great advantage of this type of pump is that liquids, air, gases, and vapors can be transported and compressed without being compromised by lubricants.

Sucker Rod Pumps

The sucker rod pumping system is the oldest, most economical, and most commonly used artificial lifting method.

This pump has a reduced piston adapted to work in oil wells at greater depths.

It is mechanically simple and can work under a wide range of conditions and also has a wide variety of available parts like valve balls and seats, pump barrels, and many more.

With all these conditions, this pump is well- accepted, and sucker rod pumps produce approximately 80% of all artificially lifted wells.

Advantages of The Sucker Rod Pumping System

This pump can be used with corrosive and viscous fluids
it is resistant to high-temperature fluid
it is easy and straightforward design and the selection and also low replacement cost.
This pump is flexible with a wide scope of operations.
It is easy to operate in the field, well-known technology.

Disadvantages of the sucker rod pumping system

This pump is not suitable for deviated wells.
It is not also suitable for high production volume or high-water content.
It is limited to depth due to rod and pumping unit elongation and resistance.

The Sucker Rod Pumping System

The sucker rod pumping system is widely used in oil fields.

It has three parts: the surface transmission unit converting rotational motion into linear motion, sucker rod string rod as a joint between the surface and downhole and reciprocating pump exploiting the oil.

The significance of predicting the sucker rod pumping system’s physics responses is to determine the operating situation and oil production.

For this equipment, it is generally set up in an open-air environment.

The test data device mounted on it is usually broken, mostly the primary working subsystem, located nearly one kilometer or more down-hole, making it almost impossible to be tasted.

Therefore, a more precise sucker rod pumping system simulation model should be established.

The sucker rod pumping system can be divided into a rod string longitudinal vibration model, surface transmission model, and downhole pumping model.

Integrated Simulation Model

The improved sucker rod pump system model is a nonlinear fluid-solid coupled model made of drive, transmission, and load.

The motor is used to generate power, and its rotation motion is transformed into a linear movement of suspension point.

This linear motion is transferred to the plunger through rod string longitudinal vibration.

The plunger motion influences pumping fluid by regulating pump pressure. Fluid motion affects pump pressure, which also the main factor in determining pump load.

Surface Boundary Model

The surface boundary condition refers to the suspension point’s motion, with the same assumption that the surface transmission mechanism consists of belt-reducing gear and four-bar linkage as a single degree of freedom system.

This new model is an improved method from the current boundary models in light of the interaction among pump pressure, gas dissolution and evaluation, inertia head loss and local head loss, pressure drop due to fluid gravitational potential energy.

Ways of Decreasing Production Prices for Sucker-Rod Pumping

Sucker-rod pumping is a prevalent means of artificial lift worldwide, mainly due to its long history. About two-thirds of the producing oil wells are on this type of lift.

To maximize profits from these wells in the economic situation, which is always changing, installation designs must ensure the best conditions with rising electric power costs.

The great pumping mode maximizes the lifting efficiency and also reduces prime mover power requirements and electrical cost.

The operational efficiency of the surface equipment is improved by using the best counterbalancing of the pumping unit.

The tapered rod string’s mechanical design must be made appropriately to account for a complete sucker-rod-pump system.

The paper guide gives aspects and details of installation design improvements along with practical examples.

Improving Energy Efficiency

To improve the profitability of sucker rod pumping installations, the reduction of operating cost is substantial since an electric motor drives most of the installations.

The cost of electric energy has increased in recent years, energy losses both downhole and on the surface must be minimized.

Downhole Energy Losses

The sucker rod pumping system is designed to lift the given amount of liquid from the well bottom to the surface.

The hydraulic power is calculated based on the depth of the significant lift and the liquid volume.

Optimum Counterbalancing of Pumping Units

Proper counterbalancing of a pumping unit levels up the torsional loads on the speed reducer during the pumping cycle.

Without counterbalancing, the gearbox’s toque loading would be high during the upstroke due to the polished rod’s high loads.

Pitfalls in Rod String Design

A well-designed rod string should provide failure-free pumping operations for a very long time.

Rod string design aims to determine the rod sizes used in the string, the lengths of single taper sections, and the rod materials.

Thus, to find an ideal solution to the above problems.

The two known problems in rod string design concern:

How rod loads are calculated
What concept to use for the determination of taper lengths?

At the time of design, the expected rod loads are not known, and they also depend on the taper lengths that are about to be determined.

So, one must rely on approximate calculations to find probable rod loads that will occur during pumping.

Pump Operating Problems and Solutions

There are common ways in which downhole pumps are abused, and they include:

Over pumping the well
Gas interference
Pump hitting up or down
Trash entering the pump

Since the recommended pump-displacement design is for the pump to have greater capacity than the well, and over pumping, the condition may occur if the well is not adequately controlled.

Over pumping may lead to mechanical damage to the pump or damage uphole to the rod/tubing, increased buckling, and wear.

To help reduce severe over-pumping properly, setting a well should be considered.

Indications of gas interference include low volumetric efficiency, whereas the fluid level survey shows noticeable, adequate pump submergence and a polish rod that is very hot to the touch.

A dynamometer survey may indicate gas lock, gas pound, or inconsistency with the assumed condition when combined with the applicable design conditions’ precalculated well loads.

The gas interference condition may be corrected by increasing the pump compression ratio, if possible. If these standard solutions do not resolve the problem, then unique pumps may be considered.

A pump component hitting on the up or downstroke is indicated by a rapid load change and can be shown with a load-capable dynamometer.

This condition typically occurs because of inadequate pump spacing as the fluid level pumps down or because the pump has a low compression ratio/excessive waste space for the seating depth for the designed pumping parameters.

This condition can also be magnified for tubing that does not have an anchor or if the anchor is not set correctly.

Other conditions that can also cause this problem include if the pump-intake piping is plugged or not precisely designed.

If the pump won’t have enough compression ratio, the polished-rod clamp is not sufficiently tightened, or the pump barrel is not correctly sized.

Factors to Consider When Selecting Submersible Pumps

Probably you’ve heard the saying that less is more.

Well, that’s not always true.

When it comes to selecting a pump, then more information is essential.

Different variables play a direct role in how long a pump will last and how it will operate.

If you are unsure how to select the right pump or the correct information you should know before contacting a vendor, you are not alone. We have put together a list of things you should know when selecting a pump to help you through the process

1.Process Liquid Properties

What type of liquid is the pump meant for? The liquid properties that must be considered before selecting a pump include:

Temperature
Specific gravity
Vapor pressure
Solids present & concentration
Shear sensitive
Abrasive or Non-abrasive

2.Materials of Construction

What are construction materials that are compatible with the process liquid or any other liquids the pump might come into contact with?

A chemical compatibility chat is available to help you identify the most appropriate construction materials for the pump.

3.Is the Pump Critical to Plant Operation?

In important applications, where downtime is not an option, more expensive, heavy-duty pumps with more unique features can be chosen.

4.Pump Inlet Conditions

You wouldn’t want to starve a pump. System net positive suction head (NPHS) available can be calculated by knowing pump inlet pressure and liquid vapor pressure.

5.Pump Environment

If the pump is outside, special construction or installation considerations may need to be made for freezing temperatures.

If the environment is hazardous, special moto features will be required. These are some of the environmental conditions to consider.

6.Power Source Availability

The most used power source in the United States is 115-230 Volts/60 Hertz/1-phase or 230-460 Volts, 60 Hertz/3-phase.

Special motors can be specified for operation outside the United States or by using DC batteries.

Pressurized hydraulic oil or compressed air is also used for power

7.Flow Rate and Pressure

Total volume and knowing how much time you have to move the fluid will determine the flow rate.

By reading and understanding the factors listed above, you equip yourself with the knowledge necessary to select the right pump.

No matter the application, you can be confident with your next pump selection.

By understanding the above factors, you’re arming yourself with the knowledge necessary to select the right pump.

Regardless of the application, you can feel confident with your next pump selection.