Development of a Novel Laser Surface Treatment Manufacturing Process for Improved Wear Resistance of Drill Chucks
Challenge
Mincon Group PLC is an engineering company that specialises in developing, manufacturing, and servicing hard-rock drilling tools for a variety of applications. The company produces Hy-Tuf drill chucks for rock drill applications. The drill chucks and bits experience significant abrasive and erosive wear while in use, requiring frequent downtime and replacement. Improvements in wear resistance would significantly enhance the product value proposition and competitive position.
Goal
The goal of this project is to provide a method of improving the surface hardness and wear resistance of the drill chuck. This will be achieved by developing a case hardening process by means of a high power fibre laser. Once designed and commissioned at DCU, a similar set-up will be implemented on line at Mincon. Process parameters will be optimised within the facility at DCU and transferred to the production system within the company. It is anticipated that the project will reduce process cost that would otherwise require time consuming post processing heat treatments. Another challenge being investigated is related to the insertion of drill bits in the drill head. Due to wear and tear of the drill head, there can be a loss of drill bits during the drilling process. A laser texture-based bonding technique that can be used to enhance the bond strength is being investigated for improved bit bonding within the drill head.
Results
The newly developed processing technique has delivered a significant (75 to 100%) improvement in drill chuck lifetime in trials, depending on ground type. The novel system will be developed on the production line at the company site. The I-Form research team and the company representatives are working together to enhance the production rate and drill wear resistance based on the feedback coming from the different sites. For the tungsten carbide bit insertion testing, laser surface texturing was implemented on the tool steel and the load on the bit was recorded as it was processed. The load profile was compared against the current method for bit bonding. Similar levels of load were achieved with a tighter control on load level for the laser textured interference fit bonding method. For future work, the research on the laser internal surface texture for the bit-insertion will be advanced to achieve the optimum mechanical force bonding between the bits and the chuck head.
Impact
The new material hardening processing and bonding steps have the potential to differentiate the company versus the competition based on the performance and robustness of drill parts produced. The main benefit for the company will be a component with longer and better defined lifetime compared to currently available alternatives. This process could also reduce the processing time from several hours to minutes and avoid the use of the traditional method and the associated high energy consumption of the furnace. Full integration of the technology is expected to reduce costs and facilitate an increase in market share.