Concord Screen Inc manufacurer of wedge wire screens laterals headers screen vee wire profile filters filter nozzles elements.

Model ACM Design, Features & Operation

Model ACM strainers are offered in capacities up to 10,000 gallons per minute. The strainers are offered for either Horizontal or Vertical installation and are available to 0.0006" degree of cleaning using Concord's own "POSI-CLEAN" elements.

The ACM has a larger screen area, providing more filtering surface than any other same size automatic strainer in the marketplace, equating a higher filter open area to inlet area ratio; this allows longer straining cycles and less backwash disposal and electrical usage.

The ACM strainer is a fabricated, single body vessel with multiple straining elements. It was designed as a fully automatic self-cleaning strainer. The vessel is available fabricated to ASME Code latest edition and addenda ("U" stamped) and National Board Registered, or built in general accordance to ASME Code without code stamp or registration. In Canada, it is available also with "CRN" registration as required by provincial codes.

Inlet and outlet connections are on the sides. The debris laden fluid enters the large lower chamber where it slows down and heavier contaminants settle to the bottom. The fluid flows upward into the straining elements. The fluid then passes through the screen media and exits the strainer through the outlet nozzle. Contaminants gather on the inside of the straining elements.

The ACM strainer can perform self-cleaning (backwashing) without interruption of the flow. These strainers are designed primarily for water service where large quantities of debris must be removed. The ACM strainer uses a motor driven backwash arm to clean the straining elements. The strainer is backwashed by starting the backwash drive and opening the backwash drain valve. This backwashing reverses the flow through each straining element sequentially. The backwash assembly is rotated to cover one element hole in the tube sheet opening a flow path to the outside via the backwash drain. The strainer utilizes system pressure and a percentage of system flow to backwash the straining elements. The controls to accomplish this can be as simple as a toggle switch to start and stop the backwash drive motor and a manual gate or ball valve to control the system backwash flow.

The ACM straining element is a cylindrical, reverse wound and resistance welded wedgewire tube ("POSI-CLEAN") that is closed at one end and open at the other. Flow during straining is from the inside to the outside of this straining element. Flow direction for backwashing, however, is opposite. The straining elements are constructed for easy replacement. They are held in place with hold down rings or plates, bolted to hold down rods. The backwash arms provide a flow path for the debris collected and the fluid to dislodge the debris during the backwash cycle. The backwash arm directs the dirty fluid to an open pit or tank at atmospheric pressure outside of the strainer. The arm is slowly rotated to allow each straining element to be backwashed during a revolution. Each straining element is isolated by a backwash shoe.

The backwash drive system converts the high rotational speed motion of the electric motor to a low rotational speed so as to more effectively backwash the straining element. A shear pin protects the gear reducer, shafting and backwash arm. The backwash system consists of the backwash arms, the backwash shoes and piping that allows the backwash fluid to exit the strainer to an open or low pressure dirty outlet connection.