Rebuilding through hardened tool steel screws
High vanadium tool steels CPM 9V and CPM 10V are proven and well respected materials for screw, barrel and valve components in the Plastics Industry. CPM stands for Crucible Particle Metallurgy. CPM steels are HIP consolidated from tiny powder particles. The result is a fine grain microstructure. First introduced in the 1980’s, they have come to be regarded as the materials of choice by molders processing highly abrasive engineered resins. The through hardened screws multiplied the wearlife over previous hardsurfaced chromed and nitrided screws. The downside was that these screw were thought not to be rebuildable. Due to their metalergical make up and hardness they were prone to breaking once the weld was applied. For years, molders discarded worn CPM 9V screws and bought replacements. That is, until 1989, when Concor Tool pioneered a way to rebuild those screws. Since then Concor has rebuilt over 1500 tool steel screws in addition to a countless number of chromed and nitrided screws.
Working closely with steel suppliers, welding supply manufacturers and heat treators, Concor was able to look closely at the alloy chemistry to determine the proper hardsurfacing and heat treating method. This process was unheard of in the Plastics Industry. Finally, screws no longer needed to be discarded. Not only were molders saving money in rebuilding but lead times were much improved
CPM 9V screw rebuilding requires expertise:
- Screw must be prepared properly for welding
- Select compatible weld must be carefully applied
- Straightening is most critical
- Stress relieving and heat treating are required
Successfully rebuilding CPM 9V tool steel screws requires knowledge about metallurgical properties, operating conditions and heat treating cycles. That knowledge, combined with expert machining capabilities make Concor the industry source for through hardened tool steel screw rebuilding. We are the tool steel experts.
