Traveling water screens are a crucial piece of equipment for many power generation, paper production and municipal water treatment facilities. These screens ensure that machinery and other channels within the facility have a steady flow of clean, debris-free water.
Not all facilities use the same type of traveling water screen. They can use either a thru, dual or center flow screen depending on how much water needs to be taken in and what type of debris needs to be dealt with. Read on to find out a little bit more about out how each type screen works and their unique features.
Thru Flow Traveling Water Screens
Thru flow screens are the main type of traveling water screen used in the United States, probably because they are simpler and cheaper to install than other types of screens.
As you can see in the illustration above of a thru flow screen, the screening mesh is oriented perpendicular to the water flow. On this type of screen, debris only accumulates on the ascending side.
Another advantage of a thru flow screen is a uniform flow of water through the screen. As a result, these screens can deal with larger amounts of debris and larger pieces of debris. They also allow for the use of grab style trash rakes to remove debris.
Dual Flow Traveling Water Screens
On a dual flow screen, the screening mesh is oriented parallel to the water flow, so the water passes from the outside to the inside of the screen. As the water passes through the screen, debris accumulates on the outside of both the ascending and descending baskets. With twice the screening area, more water can be filtered and more debris removed.
Two of the best features of dual flow screens are:
Smaller screen width, so less area is needed to install this type of screen
Less carryover of debris to the clean water stream (which often happens with thru flow screens) is eliminated.
Center Flow Traveling Water Screens
Center flow screens are similar to dual flow screens because on both types, the screening mesh is oriented parallel to the water flow. But on a center flow screen, the water passes from the inside to the outside of the screen, with debris accumulating on the inside of both the ascending and descending baskets (the opposite of the flow of water through dual flow screens).
Just like dual flow screens, center flow screens have less debris carry over and smaller screen width. But center flow screens require less steel for their framework, saving space and money.
Whether your facility has a thru, dual or center flow traveling water screen; our skilled maintenance team can service them all. They also service all brands of traveling water screens. No matter what type of screen you have, we've got you covered! Visit our traveling water screen service options page to learn more.