9 QUALITY FEATURES Carbide edges Our innovative, patented Heller carbide metal edges have been optimised for the most challenging ap- plications in concrete and masonry, even for reinforcements in concrete. An aggressive carbide metal profile ensure fast drilling progress. The integrated tip design ensures ideal drilling performance and perfect centring. The precise workmanship of Heller drill bits is evidenced in the precise alignment and soldering of tungsten carbide plates and the low run-out values. Milling processes The helix is produced by grinding or milling. The spiral is created from solid material. This guarantees the precision of the spiral progression. The external and internal diameter dimensions of the helical are precisely complied with. The benefits during application include a smoother drilling process and con- tinuous drilling dust removal, thus minimising the deflagration risk. Helix shapes Patented helix shapes guarantee optimal removal of drilling dust without risk of deflagration, for ex- ample, thanks to alternating narrow and wide backs. Maximum speed with ideal impact energy perfor- mance is a result of reduced friction thanks to computer-aided design. Heller curing technology HST The special HST curing process ensures an ideal surface texture: Heller hammer drill bits thus only exhibit minimal susceptibility to breakage under the most demanding applications – even including im- pacting on reinforced concrete. Ideal especially for long bits, the HST curing process at the same time guarantees excellent bending flexibility without the risk of breakage. Run out check Each Heller drill bit is subject to a detailed run out test after having completed production. Comput- er-controlled measuring sensors identify deviations within the micro millimetre range. The advantages for users are more precise holes in terms of diameter and depth as well as lower degrees of vibration during operation. TIPS AND TRICKS Check for reinforced concrete Heller hammer drill bits will also stand up to reinforcements. Despite this, it is still a good idea to check the wall structure with a detector before you start drilling and to drill mason- ry only wherever possible. Reinforcements are integrated into constructions for reasons of structural strength and shouldn‘t be cut if this can be avoided. If you cannot avoid this for design reasons, you need to consult a structural en- gineer before you start. Check for piping and cable routing When you start drilling, it is a good idea to check the area for piping and cable routing. Cables and pipes normally lead vertically up and down to the socket or fitting. For this rea- son, it is a not recommended to drill directly above or below fittings or sockets. For through hole drilling you should al- ways analyse the structure of the opposite side. Use a spe- cial detector for this purpose. Grease the shank & remove residual materials We recommend greasing the shaft end of the bit before in- serting into the chuck. This will extend the service life of your hammer drill. Before fitting a plug, you should always remove material residues from the drill hole to guarantee the best possible safety for the plug. HAMMER DRILL BITS