Well Pumps Information
Well pumps are most commonly used to bring potable water up from wells and springs to the surface. Collectively, well pumps include a number of other pump types, such as jet pumps, submersible pumps, mud pumps, and bladder pumps. Well pumps may be used for other applications beyond well water collection, such as unloading tankers or storage tanks, and may include pumping other material besides water, such as oil or natural gas; or, less commonly, chemicals and petrochemicals, hazardous materials, slurries (especially ash slurries), and wastewater. While they are mostly found in home wells, in water distribution services (municipal and agricultural), and mining or other fuel production applications, they are also found in construction and commercial service industries.
Water well pumps are divided into two main styles; shallow well pumps and deep well pumps. Shallow well pumps are generally located above ground to lift water out of the ground through a suction pipe. The typical lift limit for a suction pump is 33.9 feet at sea level, which is one atmosphere of air pressure, ~ 760 Torr. Some shallow well jet pumps may be able to provide greater lift. But the normal limit for a shallow well suction pump is 25 feet at sea level. This limit declines with higher altitudes.
Shallow well pumps are used mainly when the water is near the surface or in an artesian well. The shallow well pumps are usually jet pumps. Deep well pumps are either submersible pumps that are used to pump water uphill from its inlet, which is below the water level as is the rest of the pump. Or they are two pipe jet pumps. This configuration is not restricted by suction lift limitations and has four times the depth limit for water well applications. Submersible pumps are usually impeller style ones.
Non-water well pumps include well stimulation, which is typically used to rejuvenate old or poorly producing hydrocarbon wells. Mud pumps are used to assist in drilling new well bore holes. They are typically used in the oil and gas production industry and are similar to deep well water pumps in specifications. But they are also specialty pumps particular to that industry and are made by oil and gas extraction industry supply companies and are covered in other sections of this website.
The most common type of well water pumps are the ones used to supply a house with well water. These water systems are common in rural areas not served by a central water system but by a personal well. Generally, these are submersible, enclosed electric pumps running on standard AC household current. They are made to fit inside a 6”, usually cast iron, well pipe and have a die cast top that allows the in-ground electric lines to serve it. Submersible well pumps are lowered into the well pipe by a rope that also has the electric power leads anchored to it. These are usually impeller style pumps. Another common style of pump for this deep well work is the jet style pump. Jet pumps rely on the Venturi principle. If piped correctly, jet pumps can be used in the deep well capacity. Or jet pumps can be used as a suction style shallow well pump. The standard lower limits for deep water well pumps are 80’ to 100’ versus 25’ for the shallow ones. These limits are good at sea level. They decline at higher altitudes.
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Water well pumps used for municipal or larger fresh water systems usually use above-ground electric motors with diesel-electric generator back-up. Usually, two pipe deep well style jet pumps are used in these applications. Then, the well water is usually pumped uphill into a large above-ground water tank to provide storage and a steady pressure for the system.
Well pumps may be actuated by a wide variety of power sources. These include AC or DC power sources, pneumatic or hydraulic power, fuel powered engines (gas or diesel), manual power (hand well pumps), and solar well pumps. Beyond the small enclosed electric pumps found in home water wells, the power sources, like a diesel engine or a traditional farm windmill, are above ground and the power is transmitted to the below-ground pump by a mechanical drive shaft. It just wouldn’t be practical or prudent to place a large electric motor or a gas engine underground in the well. That could lead to contamination even if the engineering issues could be resolved.