In Commercial-Scale Production at NPE2015: KraussMaffei to Mold Seal Made of Teknor Apex's Sarlink TPV for Rigid PVC Pipe

March 6, 2015

KraussMaffei Will Use Its SpinForm® Swivel Plate System for Multi-Component Parts to Produce Gaskets for a Teknor Apex Customer Specializing in Infrastructure Pipe

PAWTUCKET, RI, U.S.A., March 6, 2015: Teknor Apex Company will supply KraussMaffei Corporation with Sarlink® brand thermoplastic vulcanizates (TPVs) for use in a unique multi-component process to mold two-component gaskets for rigid PVC pipe on the show floor at NPE2015. 

KraussMaffei will use the Sarlink compounds at its NPE exhibit (Booth W903) to demonstrate its SpinForm® swivel plate technology for producing multi-component parts. Teknor Apex will supply two compounds: 1) for the sealing side, Sarlink 4155-03, a 55 Shore A compound that meets the ASTM F477 specification for elastomeric gaskets used in joining plastic pipes in low head pressure drainage and agricultural applications; 2) for the outer ring, Sarlink 4780, an 80 Shore A compound. Teknor Apex will also be exhibiting at NPE, at Booth S24055.

The Sarlink compounds replace thermoset rubber in this application. In general, Sarlink 4155-03 has been replacing EPDM and polyisoprene by virtue of its processing flexibility. The material can be injection molded or extruded and can be welded when extruded.

KraussMaffei will over-mold the TPV gaskets on a CXW 300-1000/750 SpinForm unit with linear robot LRX-S150. The equipment will have a clamping force of 337 U.S. tons and two injection units with 2.17 and 1.97 in. screw diameters. Shot weights will be 4.27 and 3.81 oz. Cycle time will be 12 seconds.

In SpinForm technology, the knitpath parting lines are located one behind the other, and the injection units are opposite one another on the machine axis. A turntable, known as the spin unit, which rotates about the vertical machine axis, is located in the center. The SpinForm technology starts with the first and second component being injected into the mold in parallel. The resulting preform from the first component remains on the core of the spin unit's ejector side when the mold is subsequently opened. Next, the spin unit turns through 180°, and the preform is turned into the new cavity and overmolded with the second component