A custom job shop is running various threadmill applications. The part they are producing is a ¼″ and ½″ NPT joint made out of cast steel. They were using an Okuma HMC with a flood coolant to the threadmills to manufacture their products.
Previously, the customer had several steps in their production process which included having to drill a hole, taper ream, and tap. This process had a cycle time of 5 minutes for 2 holes. Their old tool performance was 70 holes per tap and 50 holes per reamer. Having problems with breaking the taper ream, the customer turned to AMEC for improvements. They also wanted to decrease cycle time while either maintaining the existing thread quality or improving the thread quality.
In response to the customer’s desire for improvement, AMEC recommended using an AccuThread 856™ ThreadMill. We recommended two different threadmills, one to produce the ¼" NPT, item #TMNK0250-NPT, and one to produce the ½" NPT, item #TMNK0500-NPT. Although the recommended speed was 281 SFM, we were able to safely increase the rates to 430 SFM and still maintain excellent tool life and thread quality. With a new cycle time of 3.5 minutes per 2 holes, our tooling reduced the customer’s cycle time by 1.5 minutes. We ran the tools for over 900 holes and they only showed minimal wear.
Due to the success of our threadmills, our customer was able to not only reduce their cycle time but also improve their hole quality. Additionally, their tool life was dramatically increased to over 900 holes.