A NEW RADAR-BASED MEASUREMENT TECHNOLOGY ENABLES PROCESSORS TO EXTRUDE HIGHER QUALITY PIPE WITH LESS MATERIAL. WITH AN AUTOMATED CONTROL LOOP, THEY GET HIGHER OUTPUT AND LESS SCRAP, WHICH SIGNIFICANTLY REDUCES COSTS.
Municipal pipe extrusion is often more art than science. Actually, that's a nice way of saying that without reliable measuring instruments and process controls, processors are forced to use less precise methods of quality control that are cumbersome and usually result in higher material consumption than is required to produce pipes that meet all relevant industry standards.
Extrusion of municipal piping is often more art than science. Actually, that's a nice way of saying that without reliable measuring instruments and process controls, processors are forced to use less precise methods of quality control that are cumbersome and usually result in higher material consumption than is required to produce pipes that meet all relevant industry standards.
iNOEX's new radar-based inline measurement systems finally enable real-time, data-driven process control in pipe extrusion. With the ability to accurately measure pipe wall thickness, diameter and roundness, these systems enable processors to reduce the amount of material required to meet the most demanding quality standards and reduce scrap, while virtually eliminating the production of non-conforming products. By integrating the
measuring system with iNOEX gravimetric feeders, you can also close the loop in an automated process that automatically adjusts for process deviations to keep the line running consistently day after day. You can even improve throughput by feeding the material at the same rate while increasing the take-off speed. Here's how it works.
Precise measurement of wall thickness is the key.
iNOEX's WARP radar sensor measurement systems use radar technology to precisely measure all relevant dimensions of a pipe based on echo detection. No contacting coupling medium is required to transmit and receive the radar waves, making the device very robust, reliable, and independent of process fluctuations.
In operation, a radar sensor works according to the time-of-flight principle to calculate very precise physical measurements. A sensor unit emits an electromagnetic wave that returns as an echo when it hits an object. In pipe extrusion, the first echo occurs when a pulse hits the outer diameter of the pipe, the second when it hits the inner wall (or more precisely, the air behind it), and the process is then repeated on the opposite side of the pipe. By measuring the time that elapses between the emission and the echoes, very fast and accurate dimensional measurements can be calculated for wall thicknesses as small as 5 mm (0.200"). Measurements are made with an accuracy of ±0.05 mm (0.002") and a repeatability of ±0.102 mm (0.004") even at line speeds of up to 15 m/min (50 feet per minute).
WARP measurement units include a series of these sensors arranged around the circumference of the pipe and can be placed at multiple locations on an extrusion line. WARP 8 systems provide real-time measurements of wall thickness and diameter at 8 points around the pipe, and more sensors can be used if desired. For applications with the highest quality inspection requirements, WARP 100 uses more sensors to provide 100% measurement around the pipe circumference as well as in the direction of extrusion, and to detect eccentricity and ovality.
With this measurement data, pipe manufacturers finally have a robust and user-friendly tool that, for the first time, allows them to see the real variation in their extrusion processes. Once a reproducible process margin is established, the material feed or haul-off speed can be adjusted to use the minimum amount of material to produce pipe that is 100% compliant with quality standards. This allows processors to safely maintain the lower limit of the required wall thickness, resulting in large material savings on a high-performance extrusion line.
According to iNOEX, average savings of 2% or more are common, with the investment in the measurement technology paying for itself in about a year in historical raw material cost savings alone, with payback even faster given current market prices for raw materials. But these are not the only savings. The measurement data enables processors to get their equipment to produce a product to specification more quickly once production has started, and process deviations are detected early so that problems can be discovered and corrected before a defective product is produced. Both factors can lead to a significant reduction in scrap.
In addition, because less material is needed to produce a consistently standard product, you can continue to feed the material into the line at the same or a comparable rate and increase the haul-off speed. This usually increases the throughput of the extrusion line by about 2 %. More pipe with less material is an excellent strategy for a more economical line.