Smith & Loveless, Inc. Grit Chamber PISTA® 360™

The PISTA® 360™ Grit Chamber is equipped with the V-FORCE BAFFLE™, which is an integral flow control baffle for both the inlet and outlet of the main chamber. The V-FORCE BAFFLE™ is designed to direct the inlet flow into the chamber in a manner ensuring the proper vortex flow and to prevents short-circuiting, allowing for a full 360° rotation through the inlet and outlet, providing maximum grit removal. The V-FORCE BAFFLE™ on the outlet directs the flow out of the unit and acts as a “slice weir” to control the water level in the main chamber and in the inlet channel. No additional downstream flow control device is required to keep the velocity between 3.5 f/s (1.1 m/s) at peak flow and 1.6 f/s (.5 m/s) at minimum flow with a 10:1 turn down. This most recent innovation further enhances the world’s best grit removal scheme, providing many engineering and cost saving considerations. By increasing chamber velocity during low flow periods, the baffle extends the grit extraction path within the vortexing grit chamber. This is key because a longer grit path within in the flow pattern increases the effectiveness of grit being captured on the chamber’s flat-floor. Beyond this, the PISTA® 360™ with V-FORCE BAFFLE™ also permits design flexibility so that water elevations can be controlled. Water level control is important because it maintains the proper velocities approaching the grit chamber. Previously, the most common way to accomplish water level control was to back up the flow with a downstream, submerged weir. The PISTA® 360™ with V-FORCE BAFFLE™ with its preset inlet and outlet openings supplants the need for the submerged weir. By integrating the water elevation settings with the baffle, the overall outlet footprint requirements decrease as much as half the typical distance. The resulting smaller footprint provides significant construction cost savings.