Prospecting Water Pumps - Some Basic Thoughts

Written by DOC

You will get efficient and thoughtful service from SGB.

We get a lot of 'pump' questions, so I figured I'd grab some posts from the last year and put them into this post.

Here is our 'small pump' storage room.

Some Q&A

You state in your video that a Semi-Trash pump will not work for dredging. Is this because of the PSI? The HydroForce Nozzles require 40psi. I then realized that some of the Trash Pumps only have 38psi. I wish you had a link under the 'pump section' on all of your Highbankers of the recommended Pump that will work for dredging also with your Highbankers.

There are really two types of pumps for prospectors.
Semi trash pumps and high pressure pumps.
Semi trash pumps will move large amounts of water with not too much PSI. Most 2' and 3' semi trash pumps are rated about 35 ' 42 psi. Rocks, sand and gravel, up to about 1/4' ' 1/2' can pass through these based on the pump.

We like the Champion 2' as far as 'cheap pumps' go.  it comes with just about everything you need to get 'started'. But you'll probably replace some of what it comes with.

High pressure pumps have different 'water moving' parts with tighter tolerances. (for lack of a better word) This gives them higher pressure. On a 2' it might range from 70 ' 95 PSI. Often the GPH is about the same.

If you are dredging'. you always want to overpower your unit with psi. This will allow you to run your engine less than full throttle and still have REALLY good suction. We have run our mini (1.5' dredge) with the same high pressure pump as our 4' dredges. We simply let the motor run just above idle. Running a 2' then move the throttle up more. Running a 3' more' etc. GPH is usually not the key issue with pumps and dredges. Most high-pressure pumps have good gph.

The Northern Tool Northstar 2' high pressure pump is a GREAT pump to use for dredging.

Just remember' MAKE A FINE SCREEN FOR THE INTAKE HOSE. 

If you let gravels and large sands into the pump you will have to open up the impeller and clean them out. The pump will stop working. Put a fine screen that uses 1/8' mesh (or smaller) around the pump.

Now the questions is''.. can I use a high pressure pump on my unit as a highbanker?

Yes, usually with no problem'. but it can be hard to control the GPH on a high pressure pump. (Because it is is high pressure.)  If you do'. reduce the flow at the PUMP with a ball valve or gate valve.

PSI needed for GOOD dredging?

These are 'minimum ball parks' for good performance.

Remember' we have used a 90 psi pump on a 1.5' dredge nozzle.
ALWAYS go higher than you might need.

1.5' '' 40 psi.

2' ''' 50 ' 60 psi.
2.5' ''. 50 ' 70 psi

3' ''' 80 psi

4' '''. 80+ psi

5''''. We like to run dual 2' pumps that are rated at 90 PSI.
Note: We only have to run them at about 50% rpm for great suction.
This is on a DUAL hose jet log.
6''''. Same as above but pumps run at 100% RPM.
Or run the 3' high pressure pumps necked down to 2'.
When you do this, the RPM can be 50% due to the increase
in GPH and PSI.

 

Also here is a head lift to PSI conversion tool
http://www.convertunits.com/from/psi/to/foot+of+head

Can I reduce a pump, I was told it was bad for it?

It REALLY frustrates me when I hear people being told that reducing a pump will 'burn it out'. NOT TRUE.

Reducing a pump'

Shown below is what I use to reduce 2' semi-trash pumps to 1.5' hoses.
We also use the same setup to reduce 3' pumps to 2'
Reducing at the pump saves money on hose and bulk.
Also'. before you glue it up, MAKE SURE the handle clears the 'roll cage' around the pump.
Otherwise you won't be able to screw it on. Yes, guilty as charged.
ALSO'. reducing the pump OUTFLOW will NOT damage the pump. 

If someone has told you this' send them this article.
It's not that they're stupid' they are just passing down a MYTH.

'Most engineers falsely believe that the RPM of a pump must be reduced for the power required to also be reduced. This is simply not true when you are talking about pumps with centrifugal impellers. With these type pumps the excess backpressure (created by choking a pump with a valve) is a free by product of horsepower. As the pump pressure increases, the weight of the water being lifted is reduced and the power required decreases. With centrifugal impellers, restricting the flow rate with a valve reduces the power required proportionally. When pumping fairly cool water, these type pumps can be choked back to very small flow rates without any harm to the pump or motor. It is easy to tell if an engineer or pump installer truly understands what they are talking about if he or she understands this counter intuitive property of centrifugal pumps.'
http://www.cyclestopvalves.com/csvtechinfo_21.html
It is actually GOOD for a pump.

How far or how much hose can I use?

If you are even asking that question' I would go with a high-pressure pump. If you're ever going to need a LOT of hose or a lot of lift, get a high pressure pump. Good example would be working beaches where with the tides, you may end up running 200 feet of hose.

You end up losing gph and pressure the more resistance you have from hose length and lift.

Should I buy a GOOD quality pump or get a cheap one?

I really can't answer that question for you but will give you these thoughts.

Most high-pressure pumps are in the 'expensive' range, so cheap is not an option really.

If I'm going 'prospecting', I prefer to bring two cheap pumps. It gives me a backup. If one fails I grab the other and my trip is not ruined. Theory there is I can buy two cheap pumps for the price a 'good one'.

If I'm 'mining', like running a pump in one place 8 hours a day, 5 days a week, I want a quality engine and pump. I'm a Honda fan on water pump engines.

Any tips on pumps?

Yes, at the end of the trip or end of the season, shut off the gas line and let the pump run until the gas drains from the lines and the pump quits. Always store with a fuel stabilizer made for storage.

Change your oil every season or every 40 ' 80 hours of run time. The hotter it is the more often we change it.

Always have an extra pull cord around. The best pump in the world can't run without it.

Dredging operations typically employ specialized pumps known as dredge pumps. These pumps are specifically designed to handle the unique challenges of dredging, which involves the removal of sediment, debris, or other materials from bodies of water or the seabed.

There are different types of dredge pumps used for various dredging applications, including:

Centrifugal Pumps 

Centrifugal pumps are commonly used in dredging operations. They use an impeller to create a rotating motion that imparts energy to the fluid, enabling it to be transported. These pumps are efficient and can handle a wide range of flow rates and pressures.

Sand Gravel Dredge Pump Set

The company is the world’s best Dredger Pumps solutions supplier. We are your one-stop shop for all needs. Our staff are highly-specialized and will help you find the product you need.

Gravel sand pump is designed for continuously handing the most difficult higher abrasive slurries which contain too big solids. The big particle gravel sand pump is casted as a single pump casing structure with smooth over-current channel .The overflow part is made of hard nickel and high chromium wear resistant alloy. The outlet direction of gravel pump can be adjusted according to the request direction. The gravel sand pump is suitable for delivering strong abrasive slurry containing bigger particles in mining, explosive sludge in metal melting, dredging and so on. The advantages of the pump are heavy flow, easy installation and operation, good performance of NPSH and abrasion resistance.

 

Submersible Pumps 

Submersible pumps are designed to be fully submerged in water during operation, and they are commonly used in smaller-scale dredging projects or in situations where mobility and flexibility are important.

Submersible dredge pumps are specifically designed to handle solids, including sand, gravel, silt, and other sediment. They are equipped with impellers and volutes that are designed to handle abrasive and viscous materials commonly encountered in dredging operations.

Electricit Submersible Sand Pump With Agitator

One of the advantages of submersible dredge pumps is their ability to operate at various depths. They can be lowered to the desired depth in the water, allowing for precise dredging in specific locations. This makes them well-suited for applications such as harbor maintenance, pond and lagoon dredging, or sediment removal in shallow water bodies.

 

In addition to handling solids, submersible dredge pumps are often equipped with features such as agitators or cutters to aid in the loosening and breaking up of compacted materials. This enhances their efficiency in dredging operations by improving the pump's ability to handle cohesive or compacted sediments.

 

The submersible design of these pumps also helps to minimize noise and vibration, making them suitable for environmentally sensitive areas or urban settings.

A hydraulic submersible sand pump is a type of submersible pump that is specifically designed for handling sand, gravel, and other abrasive solids in various applications. It is commonly used in dredging, mining, construction, and other industries where the efficient removal or transfer of sand or sediment is required.

Hydraulic Excavator Driven Submersible Sand Pump With Side Cutters

Overall, submersible dredge pumps offer versatility, maneuverability, and the capability to handle solids, making them a popular choice for smaller-scale dredging projects or applications in confined spaces.

Cutterhead Pumps 

Cutterhead pumps are specialized pumps used in cutter suction dredgers. These pumps are equipped with rotating cutterheads that break up and loosen the material at the dredging site. The pump then suctions the loosened material and transports it through the pipeline. Cutterhead pumps are indeed specialized pumps used in cutter suction dredgers. These pumps are designed to handle the unique requirements of cutter suction dredging operations.

Cutter Head Dredge Pump Dredger

 A cutter suction dredger (CSD) typically consists of a floating vessel equipped with a cutterhead, suction pipe, and discharge pipeline. The cutterhead pump is a crucial component of the dredging system.

The cutterhead is a rotating device located at the front of the suction pipe. It is equipped with a set of rotating cutting blades or teeth that break up and loosen the material at the dredging site. The cutterhead can be powered by hydraulic motors or electric motors, depending on the design of the dredger.

As the cutterhead rotates and cuts through the sediment, the loosened material is mixed with water to form a slurry. The cutterhead pump is responsible for creating suction and drawing the slurry into the suction pipe.

 

Inside the pump, an impeller or series of impellers generate the necessary centrifugal force to transport the slurry. The slurry is then discharged through the discharge pipeline and transported to the desired location, such as a sediment containment area or a designated disposal site.

 

Cutterhead pumps are specifically designed to handle the abrasive nature of the dredged material, such as sand, gravel, or clay. They are built with wear-resistant materials and components to withstand the erosive forces encountered in the dredging process.

 

Jet Pumps 

Jet pumps, also known as eductors or ejectors, utilize the principle of fluid entrainment. They use high-velocity jets of water or a mixture of water and air to create a suction force that lifts and transports the sediment. Jet pumps are often used in shallow water or for precision dredging tasks.

 

The type of pump used for dredging depends on factors such as the type of material being dredged, the depth and location of the dredging site, the desired flow rate and pressure, and the specific requirements of the project.

Jet pumps, also known as eductors or ejectors, are commonly used in dredging operations, particularly in shallow water or for precision dredging tasks.

 

Jet pumps operate based on the principle of fluid entrainment. They use high-velocity jets of water or a mixture of water and air to create a suction force that lifts and transports sediment or other materials.

Dredge Performance

The basic design of a jet pump includes an inlet nozzle where the high-velocity jet is generated, a mixing chamber, and a discharge outlet. The high-velocity jet of water or water-air mixture is directed into the mixing chamber, creating a low-pressure zone. This low-pressure zone induces the suction and entrainment of sediment or other materials from the surrounding area.

 

As the sediment is entrained, it mixes with the water or water-air mixture, forming a slurry. The slurry is then transported through the discharge outlet and can be directed to a designated containment area or disposal site.

Jet pumps are often used in shallow water dredging operations where the water depth is limited. They are particularly effective in areas where traditional dredging equipment may be challenging to maneuver or operate.

Additionally, jet pumps are commonly utilized for precision dredging tasks that require controlled and localized excavation. Their ability to create a suction force in a specific area allows for targeted removal of sediment or materials without disturbing the surrounding environment.

It's important to note that jet pumps may have limitations in terms of the volume of material they can handle compared to other types of dredging pumps. They are most suitable for smaller-scale dredging operations or situations where precise and localized dredging is required.

Overall, jet pumps are a valuable tool in dredging operations, especially in shallow water or for precision dredging tasks, offering flexibility, control, and the ability to create suction forces for lifting and transporting sediment or other materials.

 

It's important to note that dredging operations often involve a combination of pumps, pipelines, and other equipment to effectively remove and transport sediment or other materials. The selection of the appropriate pump(s) is typically based on the specific needs and conditions of the dredging project.

If you want to dredge sand slurry ,you can contact

Taian Ocean Pump Co.,ltd

 : +86

 

For more Ash Handling Pump solutioninformation, please contact us. We will provide professional answers.