Overview: 1.
Centrifugal Pumps 2.
Self Priming Centrifugal Pumps 3.
Jet Pumps 4.
Deep Well Pumps 5.
Multi-Stage Pumps 6.
Submersible Pumps Pumps for homes and industries have evolved over the years.
Prior to the 1950's a great deal of people lived in cities where they had a central water system.
Central systems utilize large centrifugal pumps.
Outside the city there were no central water systems.
If you moved outside the city you needed a well (or cisterns) and a pump to provide your water needs.
Because the Centrifugal pumps were not made economically for use in homes at that time, these non-city dwellers used piston (reciprocating) pumps to provide their water needs from wells and cisterns.
Eventually in the early 1950's centrifugal pumps, that were made specifically and affordable for home wells, began to come on the market.
These first straight centrifugal (SC) close coupled pumps (pumps joined together with motor and pump) had a motor, a seal plate (or adapter), a mechanical shaft seal, an impeller and a volute (casing) that fit over the impeller.
Most volutes had wear rings that were replaceable and fit snug around the outside eye of the impeller.
These pumps generally turned at 3600 RPM's.
As they ran (or turned), the impeller slung water from inside out which created a vacuum inside the eye (or intake) of the impeller.
These pumps were designed with little or no lift.
They were designed to have a flooded suction (reservoirs, cisterns or artesian wells).
They took the intake water and were able to boost it to 30 to 50 PSI or a little higher.
They were able to pump a lot of volume.
Eventually in areas with little or no rainfall, property owners had to drill wells that mostly had water levels below ground.
With centrifugal pumps having little or no lifting capabilities there was a need for pumps that could lift or push water from below ground level.
Engineers first came up with a "self-priming" centrifugal (SPC) pump.
These pumps used the same components as a straight centrifugal pump except for two things that were changed.
An internal diffuser was added to the pump that bolted around the impeller, along with a larger volute (casing).
With the diffuser and larger casing these pumps could vent the air to prime and lift water up to 25 feet effectively.
Because of their design requiring them to now lift water, they produced water at the quantity of about 15% less than a straight centrifugal pump.
They also produced a little less pressure.
Typically, they operated in the 20 -40 PSI range.
Their design made them produce maximum volumes of water at the highest point of its maximum pressure.
We call these pumps a medium head/medium pressure type pump.
As homes and businesses grew outside the city, there was a need for pumps to provide higher pressures rather than larger quantities of water.
An average home would need 100 to 150 gallons per day.
At peak periods (such as early in the morning), however, water needs might be 15 gallon per minute (GPM).
Engineers then came up with a centrifugal jet pump.
Besides having all the components of a self-priming centrifugal pump, engineers added a bolt on shallow well jet.
These pumps were smaller in size than self priming centrifugal pumps (SPC), however, they could produce the quantity of water the customer needed (typically 10 to 20 gpm) at pressures up to 60 PSI.
When comparing horsepower (HP) to horsepower (HP) of a jet pump to a self-priming centrifugal (SPC), the SPC could produce more water, but at lower pressures - something the homeowner didn't really need.
These shallow well jet (SWJ) pumps operated like a SPC pump except after the water was lifted and pulled in the pump by the impeller, part of the water was diverted through the jet boosting the pressure.
These pumps could lift water up to 25 feet from ground level, however, at depths lower than 15 feet these pumps were straining to lift water.
he engineers solved the problem of inefficiency at water levels below 15 feet by installing the shallow well jet inside the well on twin pipes.
These twin pipes were attached to two holes in the pump casing, one suction hole and one driver hole.
A special 4" well seal at the top of the well would protect contaminates from entering the well.
The jet had a one way valve on the bottom (foot valve).
They also added an automatic control valve (sometimes called a back pressure or control valve) on the discharge of the pump.
This would create a deep well jet pump (DWJ).
The DWJ pumps lifted the water up through the pump impeller.
Part of the water discharged through the BPV to the home or yard, and part of the water was diverted back down the well through the driver line.
Water would recirculate through the deep well jet which would help lift more water and create higher pressures.
Because of this twin pipe system all wells had to be 4" inside diameter or larger.
Eventually a modified deep well jet was designed for 2" and 3" inside diameter wells.
In this system, only one drop pipe was needed with the deep well jet and foot valve on the end.
This new jet used cup leathers that sealed the inner pipe to the outer well casing.
There was a special well seal at the top of the well designed to hold the drop pipe and seal around the well casing.
From there, two pipes would connect into the pump.
These modified jets could produce more than enough water needed for a home.
Whether the pump system was a shallow well or deep well systems, cases occurred where the customers needed relatively low volumes of water, but at pressures over 60 PSI.
Engineers came up with the solution - multi-stage (multi-impeller) pumps.
Shallow well jet pumps that needed to produce pressures over 60 PSI were now built with two or more impellers.
They operated by the first impeller lifting the water and then throwing it into the next impeller.
The first impeller lifting the total GPM's needed, however, by throwing the water into the next impeller in increased the pressure from 10 to 15 PSI.
If it had more than one impeller then the 3rd impeller would boost the pressure an additional 10 to 15 PSI.
This is because the additional impellers did not have to lift any volume of water.
Because water volume is weight and the pump did not pump more water than a one stage (one impeller pump), then this could be done without increasing the pump horsepower.
Noting how successful the multi-stage pumps worked, engineers came up with the idea of designing a tube like pump and motor that would fit inside a 4" well.
This pump would have multiple impellers and be submerged (submersible well pump) in the well on drop pipe below the water.
An electric cable would be attached to the pump and run through a special well seal at the top of the well.
The motor was on the bottom, the water intake was in the middle and the pump was on the top.
Water would now pass by the motor (cooling it) and be pulled into the pump.
Now efficiency really came into place.
Now that the pump only had to push the water up rather than re-circulate the water in the well through a deep well pump system, these pumps could produce a lot more water at higher pressures than the same horsepower as their above ground counterpart jet pumps.
In most of the country today, water levels in wells can be extremely deep (sometimes 300 to 500 feet below ground level).
Today 85% of all wells are 4" in diameter or larger and utilize a submersible pump.
In recent years, a 3" submersible pump came on the market in order for existing 3" wells to be changed over from deep well jet system to submersible well pumps.
Submersible well pumps come in two varieties.
First there is a 3 wire pump with a ground wire.
These pumps have their starting components mounted above ground in a control box (ex: starting relays and capacitors).
These components are the ones that are the most common to fail.
They now can be replaced easily without having to use a hoist truck to lift the pump out of the well.
The second type of submersible well pump is a 2 wire type with ground wire.
All the starting components are in the pump motor, thus the pump has to be pulled from the well to be worked on.
Centrifugal Pumps 2.
Self Priming Centrifugal Pumps 3.
Jet Pumps 4.
Deep Well Pumps 5.
Multi-Stage Pumps 6.
Submersible Pumps Pumps for homes and industries have evolved over the years.
Prior to the 1950's a great deal of people lived in cities where they had a central water system.
Central systems utilize large centrifugal pumps.
Outside the city there were no central water systems.
If you moved outside the city you needed a well (or cisterns) and a pump to provide your water needs.
Because the Centrifugal pumps were not made economically for use in homes at that time, these non-city dwellers used piston (reciprocating) pumps to provide their water needs from wells and cisterns.
Eventually in the early 1950's centrifugal pumps, that were made specifically and affordable for home wells, began to come on the market.
These first straight centrifugal (SC) close coupled pumps (pumps joined together with motor and pump) had a motor, a seal plate (or adapter), a mechanical shaft seal, an impeller and a volute (casing) that fit over the impeller.
Most volutes had wear rings that were replaceable and fit snug around the outside eye of the impeller.
These pumps generally turned at 3600 RPM's.
As they ran (or turned), the impeller slung water from inside out which created a vacuum inside the eye (or intake) of the impeller.
These pumps were designed with little or no lift.
They were designed to have a flooded suction (reservoirs, cisterns or artesian wells).
They took the intake water and were able to boost it to 30 to 50 PSI or a little higher.
They were able to pump a lot of volume.
Eventually in areas with little or no rainfall, property owners had to drill wells that mostly had water levels below ground.
With centrifugal pumps having little or no lifting capabilities there was a need for pumps that could lift or push water from below ground level.
Engineers first came up with a "self-priming" centrifugal (SPC) pump.
These pumps used the same components as a straight centrifugal pump except for two things that were changed.
An internal diffuser was added to the pump that bolted around the impeller, along with a larger volute (casing).
With the diffuser and larger casing these pumps could vent the air to prime and lift water up to 25 feet effectively.
Because of their design requiring them to now lift water, they produced water at the quantity of about 15% less than a straight centrifugal pump.
They also produced a little less pressure.
Typically, they operated in the 20 -40 PSI range.
Their design made them produce maximum volumes of water at the highest point of its maximum pressure.
We call these pumps a medium head/medium pressure type pump.
As homes and businesses grew outside the city, there was a need for pumps to provide higher pressures rather than larger quantities of water.
An average home would need 100 to 150 gallons per day.
At peak periods (such as early in the morning), however, water needs might be 15 gallon per minute (GPM).
Engineers then came up with a centrifugal jet pump.
Besides having all the components of a self-priming centrifugal pump, engineers added a bolt on shallow well jet.
These pumps were smaller in size than self priming centrifugal pumps (SPC), however, they could produce the quantity of water the customer needed (typically 10 to 20 gpm) at pressures up to 60 PSI.
When comparing horsepower (HP) to horsepower (HP) of a jet pump to a self-priming centrifugal (SPC), the SPC could produce more water, but at lower pressures - something the homeowner didn't really need.
These shallow well jet (SWJ) pumps operated like a SPC pump except after the water was lifted and pulled in the pump by the impeller, part of the water was diverted through the jet boosting the pressure.
These pumps could lift water up to 25 feet from ground level, however, at depths lower than 15 feet these pumps were straining to lift water.
he engineers solved the problem of inefficiency at water levels below 15 feet by installing the shallow well jet inside the well on twin pipes.
These twin pipes were attached to two holes in the pump casing, one suction hole and one driver hole.
A special 4" well seal at the top of the well would protect contaminates from entering the well.
The jet had a one way valve on the bottom (foot valve).
They also added an automatic control valve (sometimes called a back pressure or control valve) on the discharge of the pump.
This would create a deep well jet pump (DWJ).
The DWJ pumps lifted the water up through the pump impeller.
Part of the water discharged through the BPV to the home or yard, and part of the water was diverted back down the well through the driver line.
Water would recirculate through the deep well jet which would help lift more water and create higher pressures.
Because of this twin pipe system all wells had to be 4" inside diameter or larger.
Eventually a modified deep well jet was designed for 2" and 3" inside diameter wells.
In this system, only one drop pipe was needed with the deep well jet and foot valve on the end.
This new jet used cup leathers that sealed the inner pipe to the outer well casing.
There was a special well seal at the top of the well designed to hold the drop pipe and seal around the well casing.
From there, two pipes would connect into the pump.
These modified jets could produce more than enough water needed for a home.
Whether the pump system was a shallow well or deep well systems, cases occurred where the customers needed relatively low volumes of water, but at pressures over 60 PSI.
Engineers came up with the solution - multi-stage (multi-impeller) pumps.
Shallow well jet pumps that needed to produce pressures over 60 PSI were now built with two or more impellers.
They operated by the first impeller lifting the water and then throwing it into the next impeller.
The first impeller lifting the total GPM's needed, however, by throwing the water into the next impeller in increased the pressure from 10 to 15 PSI.
If it had more than one impeller then the 3rd impeller would boost the pressure an additional 10 to 15 PSI.
This is because the additional impellers did not have to lift any volume of water.
Because water volume is weight and the pump did not pump more water than a one stage (one impeller pump), then this could be done without increasing the pump horsepower.
Noting how successful the multi-stage pumps worked, engineers came up with the idea of designing a tube like pump and motor that would fit inside a 4" well.
This pump would have multiple impellers and be submerged (submersible well pump) in the well on drop pipe below the water.
An electric cable would be attached to the pump and run through a special well seal at the top of the well.
The motor was on the bottom, the water intake was in the middle and the pump was on the top.
Water would now pass by the motor (cooling it) and be pulled into the pump.
Now efficiency really came into place.
Now that the pump only had to push the water up rather than re-circulate the water in the well through a deep well pump system, these pumps could produce a lot more water at higher pressures than the same horsepower as their above ground counterpart jet pumps.
In most of the country today, water levels in wells can be extremely deep (sometimes 300 to 500 feet below ground level).
Today 85% of all wells are 4" in diameter or larger and utilize a submersible pump.
In recent years, a 3" submersible pump came on the market in order for existing 3" wells to be changed over from deep well jet system to submersible well pumps.
Submersible well pumps come in two varieties.
First there is a 3 wire pump with a ground wire.
These pumps have their starting components mounted above ground in a control box (ex: starting relays and capacitors).
These components are the ones that are the most common to fail.
They now can be replaced easily without having to use a hoist truck to lift the pump out of the well.
The second type of submersible well pump is a 2 wire type with ground wire.
All the starting components are in the pump motor, thus the pump has to be pulled from the well to be worked on.
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