Working principle
A self-cleaning screen filter is a type of water filter which utilizes system pressure to clean itself. A rigid cylinder screen strains particles from a water source, trapping debris on the inside. This layer of buildup causes differential pressure across the inlet and outlet. A controller monitors the filter and opens a flush valve when it senses adequate differential pressure. This creates rapid flow through the internal cleaning apparatus, which vacuums buildup from the screen and expels it.
A unique characteristic of self-cleaning screen filters is that the backwash cycle does not require the entire system flow to stop and reverse, as is the case for many other types of filters. Instead, a point-of-suction backwash reverses flow across the screen only directly in front of suction nozzles. This allows the cleaning mechanism to scan and clean the screen incrementally without disrupting the main flow through the filter.
Self-cleaning screen filters are used in a variety of applications where continuous water flow is crucial, including industrial equipment protection, irrigation nozzle protection, and municipal water treatment.
The cleaning process
During filtration water flows though the cylindrical screen of the strainer from the inside out. Debris collected on the inner surface of the screen form a "filter cake" that causes a pressure drop across the screen. When this pressure differential reaches a preset value, it is detected by the filter control system and the self-cleaning process automatically starts.
A specially designed exhaust valve, opens and the drive unit starts to rotate two stainless steel brushes which sweep the inner surface of the cylindrical screen. The particles trapped on the screen are dislodged by the revolving brushes and flushed out through the open exhaust valve. Service flow of filtered water is uninterrupted throughout the approximate 20 seconds cleaning process. At the end of the self-cleaning process the motor stops and the exhaust valve closes. The filter control system continues to monitor the differential pressure and when needed starts a new self-cleaning cycle. automatic brush filters are useful mostly for heavy duty, heavy dirt load and coarse filtration applications ranging from 3500 to 200 micron.
Filtration Process
Raw water flows from the inlet into the screen cylinder. The water then flows through the screen, from the inside out, and continues downstream. Trapped dirt particles form a filtration cake on the inner surface, causing a differential pressure (typically 0.5 bar / 7 psi). A signal is the sent to the control unit which activates the cleaning process.
Cleaning Process
The control unit activates the cleaning cycle by opening the exhaust valve and starting the drive unit. The drive unit rotates two stainless steel brushes which sweep the inner surface of the screen. Dislodged particles are then flushed out the exhaust valve. The downstream flow continues throughout the cleaning cycle which lasts between 15-30 seconds.
Feature
1. Electric device of the automatic washing
2. Filtering precision is from 3500 um to 200 um
3. Simple washing way: By stainless steel brush
4. Anti- Corrosion: Phosphatization treatment, the outside steel is coated with resin; It also could be with the shell of anti- Corrosion of the seawater or the stainless steel body.
5. No cutoff for the backwashing, low water consumption: No more than 1% of the total quantity.
Application:
The circulated or non-circulated cooling water system, heat exchange system, central air conditioning system and central heating system in the industries like architecture, chemistry, metallurgy, rubber, paper making, light textile, coal and foods, used to protect the cooling equipment, heat exchange device and air conditioner accordingly.
| model |
water inlet-outlet |
housing diameter |
capacity |
weight |
| inch |
mm |
mm |
m3/hour |
Kg |
| YL-2V |
2 |
50 |
159 |
19 |
80 |
| Y-2.5V |
2.5 |
65 |
159 |
28 |
100 |
| YL-3V |
3 |
80 |
219 |
50 |
130 |
| YL-4V |
4 |
100 |
219 |
80 |
170 |
| YL-5V |
5 |
125 |
219 |
125 |
200 |
| YL-6V |
6 |
150 |
273 |
180 |
270 |
| YL-8V |
8 |
200 |
325 |
320 |
350 |
| YL-10V |
10 |
250 |
377 |
490 |
390 |
| YL-12V |
12 |
300 |
426 |
710 |
480 |
| YL-14V |
14 |
350 |
478 |
970 |
550 |
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