One of the challenges engineers face when designing a self-priming or process pump is removing air from the piping and pump casing. These casings create the suction necessary for forcing the liquid to the pump. If any air gets into the self-priming pump, it cannot operate properly. For this reason, the pump creates a vacuum at the impeller eye so that air will not get into the suction line. Air is released during the discharge phase after it has primed the liquid. The removal of the air creates the suction necessary for the pump to work. As long as the lines are clear of air, dirt, and sand, the pump can prime the liquid efficiently up to 26 feet.
Most EDDY Pumps are submersible, as opposed to a self-priming unit in which the pump and power unit are not submerged. The suction hose goes into the slurry and the unit acts like a super-sized wet vacuum. EDDY self-priming pumps are easily mounted to trailers or skids which allows for increased mobility, making it simple to pump out multiple large pits or sumps with the ability to easily handle solid, abrasive, or corrosive material.
Some Considerations When Using a Self-Priming EDDY Pump
Although EDDY Pumps are used for a wide range of pump applications, companies should consider what they plan to use them for and some of the challenges they may face. For example:
• Leak Prevention. Before using the pump, it is essential to test for leaks in the connectors, the suction line, or the pump seals. The smallest leak in these areas can prevent the pump from doing its job. Users should assess all common leak areas and make the necessary adjustments to ensure the centrifugal pump is working correctly.
• Size of the Hose/Pipe. The length and diameter of the self-priming pump hose or pipe can affect how much suction the pump generates. The longer the hose or pipe the more challenging it becomes to create the suction.
• Proximity to Water Source. A self-priming pump needs to be in proximity to the water source to minimize friction. Ideally, the user needs to place the pump directly above the cofferdam with little restrictions.
• Still must be primed initially. Prior to the first operation, even self-priming pumps must be primed for the first operation. For all self-priming pumps, there is a priming chamber or some portion of the volute that will need to be filled with water prior to use.
• Air must be vented. The air in the suction side of the pump being displaced by liquid must have a place to go, otherwise, the pump will stall and could be damaged.
• Avoid Freezing. Working in areas with colder weather, it’s important to keep the liquid within the pump casing from freezing solid by using heaters or draining the liquid when needed. Water expands when frozen, and this can end up easily cracking the casing, which can be a costly fix.
Net Positive Suction Head
The Net Positive Suction Head is the margin of pressure over vapor pressure at the pump suction nozzle. In essence, NPSH measures the difference between suction pressure (stagnation) and vapor pressure using various equations. If the margin between the pump pressure and the vapor pressure is set properly, the centrifugal pump can continue pumping liquid without any limitations in the suction. This can create a wide range of challenges that cause the pump to lose its prime due to cavitation, which can lead to equipment damage. For example:
• Not enough NPSH
• Long vertical lifts 15 feet or more
• Lines that contain obstruction
• Low pump capacity
To solve these possible dilemmas, engine drives are inserted into the system to boost the pump’s pressure power. Although the drives come with their own set of challenges — fuel level maintenance, oil viscosity, and component maintenance — they work well in ensuring that the pump operates continuously when environmental conditions are not always ideal.
Common Applications of Eddy Self-Priming Pumps
A self-priming EDDY Pump can be used for a wide range of applications in various industries. Some examples include:
• Sewage lift stations, where raw sewage is pumped using high-solids pumps into a treatment facility.
• Pumping stormwater from a facility, construction site, or dewatering a mining operation.
• Agriculture application or Irrigation for a massive land project where a significant amount of water is required.
• Transferring light fuel from the source to the destination or holding tank for oil and gas pump applications.
• Supply lines for commercial and industrial air conditioning systems.
• Fighting fires on a large scale.
Advantages of the EDDY Pump Self-Priming Pump
Due to their unique design, there are several advantages to using a self-priming EDDY Pump. Some of the advantages include:
• Optimal Performance. Built for pumping the toughest of materials including high viscosity liquids, high-solids content slurries with a non-clogging design.
• This type of pump can remove air on its own and continue operation without assistance.
• The EDDY Pump self-priming pumps can handle up to 9 inches of solids.
• It has the ability to continue pumping fluid while the pump is still situated out of the pit.
• The pump can re-prime itself without external vacuum assistance or foot valve.
• Becuase the pump is not submerged, both the operation and maintenance of self-priming pumps are economical and relatively easy.
Using Self-Priming Pump to Replace Vacuum Trucks
Many industrial operations such as drilling, paper/pulp, manufacturing, and mining have waste that must be processed and removed on a regular basis. The solution for a lot of these companies is to continually hire vacuum truck services in order to clean and remove waste material from tanks, sumps, and pits. This costly process can now be done in-house for a fraction of the price with the EDDY Pump Self-Priming System.
By replacing vacuum trucks with a self-priming pump system, you can now pump waste material directly to the disposal areas, storage tanks, or dewatering bags nearby. This process can save companies hundreds of thousands of dollars per year on vacuum truck services.
A recent client in the manufacturing space was paying $200,000.00 every year to vacuum truck companies to dispose of the waste in their sumps. They tried using other pumps, but the pumps would constantly clog and fail because of large debris, abrasive slurry, etc. This problem was solved with a 2-inch self-priming EDDY Pump for a fraction of the annual cost of vacuum trucks. Dewatering bags are perfect for materials that can be dewatered and dispersed on site.
EDDY Pump Is Perfect for Your Liquid Transfer Applications
Regardless of what you need a self-priming pump for, the self-priming EDDY Pump has the right product for you. EDDY Pump integrates a vacuum-based priming unit, which allows the EDDY Pump to operate at peak performance. They’re perfect for pumping highly viscous or heavy fluids without blocking the line or breaks in the process. EDDY Pumps require minimal maintenance and come in a wide range of size options to cover any liquid transfer project. EDDY Pumps are prepared to handle pumping distances over 3,500 feet and production rates up to 4,000 GPM. The pumps will not lose their suction pressure or suffer from cavitation due to the pumping distance. The EDDY Pump is highly efficient and can pump both fluids and solids through the pipeline.
Pump Deployment Options
With flooded suction pumps, the fluid to be pumped is positioned above the pump. With the pump positioned below, gravity can feed the fluid into the suction of the pump and keep the pump primed.
Pumps that are completely submerged in the liquid are called submersible pumps. By being submerged in the fluid to be pumped, there is no need for priming.
With a self-priming unit, the pump and power unit are not submerged. The suction hose goes into the slurry and the unit acts like a super-sized wet dry vacuum. Can be trailer mounted for added mobility.