Pump Primer
The Optimal Pump Must Be Matched to Handle What’s in the Water
By Pam Meyer
 From centrifugal to trash to diaphragm, there are several different types of pumps available. Some are designed to move thick, muddy water, while others are only capable of handling clear water. Certain pumps allow sticks, stones and various trash to flow through, where others would become clogged with such debris. Selecting the proper pump is imperative, as an incorrect choice can result in poor performance and damage to the pump’s components. To accurately choose the best pump for the job, the user must look below the surface and investigate what is actually in the water.
Simple Centrifugal
When clean water that is virtually free of debris must be moved, a basic centrifugal pump offers the most efficient and inexpensive means to do so. Certainly, there is always a chance that seemingly clear water will contain a small amount of debris. That’s why these pumps are equipped with a strainer, which stops unforeseen debris from entering the intake hose. The strainer will help prevent unexpected particles from damaging the pump; but if a user detects debris in the water, a semi-trash pump is the best option.
 Semi-Trash
In the simplest terms, semi-trash pumps have thicker internal components better adapted to allowing the passage of small debris. As a general rule of thumb, debris up to ¾ in., or about the size of a dime, should pass through without any problems. Water that appears a bit dirty or sandy should be moved using this type of pump. While a semi-trash pump is capable of handling more than a centrifugal pump, it can still have problems with larger debris. If larger debris is present in the water, opt for a trash pump.
Trash
For items too big for a semi-trash pump to handle, a trash pump is best. With even more durable internal construction, a trash pump allows larger debris to flow through. Small sticks, stones and other debris from ¾ in. to 1¼ in., or up to the size of a half dollar coin, can successfully go through a trash pump. While trash pumps can handle thicker, sandier
and dirtier water than a semi-trash, many contractors are faced with the task of moving extremely muddy, viscous water or water that contains larger solids, trash or other particles. For the toughest water with large debris, a diaphragm pump is needed.
Diaphragm
 Often referred to as “mud hogs” or “mud pumps,” the diaphragm pump is the one to choose when the water is so thick or dirty that the user cannot detect what lies beneath the surface. Diaphragm pumps are capable of handling sticks, stones, mud, trash and other debris up to 2 in. Basically, anything that can fit through the opening will pass through. All of these capabilities mean a higher price tag. For this reason, a diaphragm pump is typically used only when it’s the only machine competent. And it operates at a slower rate than the others, so be prepared for the job to take a bit longer.
Additional Criteria
Before making the final decision, there are a few more factors to consider. Pump sizes are based on how much water per minute the pump will move, and the bigger the pump, the faster it will move the water. So the amount of time the user spends pumping is an important consideration. In some cases, a smaller pump would be sufficient to get the job done, but a larger pump may be chosen to get it done faster.
Pam Meyer is an Equipment Sales Manager with Subaru. |
