Specifications include, but are not limited to: Replacement of two (2) Automatic Backwash Strainers that are inline to the secondary effluent reclaimed water pipe at the wastewater plant. The replacement strainers shall be drop-in units that require no piping changes or footprint accommodations. The strainers shall be a motorized automatic self-cleaning type, Adams VWS-20, S P. Kinney Model A, SSI Fabricated, Division of Hellan Strainer Co. Model 14” 150# RF FAZ AUTO STRAINER or approved equal. The replacement strainers shall be drop-in units that require no piping changes or footprint accommodations. The strainers shall be of standard construction with exceptions as noted herein. Construction shall withstand pressures up to 150 psi. The strainers shall have 14-inch nozzles positioned as shown on the drawings, and field verified. The internal screens shall be stainless steel. They shall be capable of handling 4,000 gallons per minute (gpm) of secondary effluent at a working pressure of 90 psi. The strainers shall remove solids larger than 250 microns (.01-inch). Pressure drop across the strainer shall not exceed 2.0 psi at 4000 gpm with 25 percent of the straining surface clogged. The average percentage of backwash effluent shall be 1 percent of the strainer influent over a 24-hour period. Provide an inspection opening suitable for visual inspection of the straining media.
