7 Fasteners for Plastics Application Examples n Assembly of cooling-water pump casings n Assembly of contactor and switch casings EJOT DELTA PT ® DS – Safe direct assembly in thermosets Detailed view with forming grooves n Smaller chip space allows for shorter hole depth, compared to screws with milled cutting edge n Easy assembly due to easy application of the screw n Larger flank coverage at the same insertion depth compared to milled cutting edge n Extended production range for diameter and length n Saving potential through standardisation: One type of screw for thermoplastic and thermoset n Saving potential through omission of threaded inserts The EJOT DELTA PT ® DS Screw ensures reliable direct as sembly into plastic. Some designs require the use of thermoset materials, which pose special demands on direct assembly due to their hardness and brittleness. Slightly modified thread ends are necessary to make a direct assembly with these very demanding materials possible. With the thread form DS (DuroSet) EJOT responded to these challenging conditions. For the EJOT DELTA PT ® DS Screw special grooves are applied to the established DELTA PT ® thread geometry, which help to cut the female thread. These grooves are pronounced at the screw point and taper off towards the screw head. The thread forming zone per mits low installation and high stripping torques.