SETT ATT KONTINUERLIGT FRAMSTELLA VERMEISOLERADE LEDNINGSROR

摘要

A blend of high and low density polyethylene and azodicarbonamid added as blowing agent is heated in an extruder to a temperature above the melting point of the high density component and fed to a shear head having a hollow rotating mandrel through which tubing is fed for depositing thereon a hose at the nozzle exit of the head. A peroxide is fed to the shear head for mixing with the polymer blend and immediately initiating crosslinking; blowing begins just prior to the depositing, the material being already crosslinked to a considerable extent.