The recent addition of an ultrasonic gauging and control system is credited by pipe extruder Charter Plastics Inc., Titusville, Pa., with increasing its production flexibility. Charter (charterplastics.com) extrudes HDPE pipe in diameters ranging from 6 to 26.5 in. and wall thicknesses up to 3 in. for potable water, reclaimed water, sewer, geothermal, gas, irrigation, and industrial applications. The Aurex ERS system from Inoex LLC, Lancaster, Pa., has 76 ultrasonic sensors that inspect the pipe in the lengthwise direction and around the full circumference. It also detects defects that might otherwise go unnoticed. The system measures pipe diameter, wall thickness, ovality, and eccentricity. Wall thickness is controlled by puller speed.
According to Charter officials, the system helps Charter produce a wide range of pipe diameters and wall thicknesses on the same extrusion line. Charter also uses Inoex’s Saveomat gravimetric blending system for automatic calibration of the ultrasonic signals. Working together, the gravimetric system controls product weight and the ultrasonic system controls the wall thickness and pipe dimension to maintain more consistent, in-spec product and reduce waste.