Drill Insert Rake-Face Coolant Delivery for Tool Life
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current drilling tools face challenges in achieving higher penetration rates due to undesirable heat, friction, and adhesion at the rake face, which are exacerbated by the increasing demand for faster drilling in high-production environments, despite the use of coolant, which typically does not effectively target the critical cutting zone.
Innovation Solution
A drill tool assembly with a holder and cutting insert featuring coolant channels and outlets that direct a curtain of coolant onto the rake face, minimizing heat, friction, and adhesion, while maintaining effective chip evacuation and tool life by targeting the interface between the chip and rake face.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If higher penetration rates are achieved by increasing drilling speed, then productivity is improved, but heat, friction, and adhesion on the rake face increase causing tool life to deteriorate
Solution Approach 1:
Coolant is delivered to the rake face before the chip arrives, creating a protective coolant film in advance. The coolant outlets are positioned to discharge coolant onto the rake face surface ahead of the cutting action, pre-cooling and lubricating the interface before heat and adhesion can build up during high-speed drilling
Solution Approach 2:
Coolant acts as an intermediary substance between the cutting edge and the chip. By introducing coolant at the rake face, it mediates the interaction between chip and tool surface, reducing direct metal-to-metal contact, friction, and adhesion, thereby enabling higher penetration rates without sacrificing tool life
2Temperature
If coolant is applied to the cutting zone, then heat and friction are reduced, but the coolant delivery system becomes more complex
Solution Approach 1:
The holder structure serves multiple functions: it provides mechanical support for the cutting insert, enables clamping and positioning, and integrates coolant delivery through built-in channels and outlets. This multi-functionality eliminates the need for separate coolant delivery components, reducing overall system complexity while effectively cooling the rake face
Solution Approach 2:
Coolant channels are nested within the holder structure itself, with channels positioned inside the holder body and outlets integrated into the clamp arms or holder surface. This nesting approach embeds the coolant delivery system within the existing mechanical structure, avoiding additional external components and simplifying the overall design
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This solution enables higher penetration rates and exceptional tool life by effectively reducing heat, friction, and adhesion on the rake face, allowing for enhanced drilling performance at elevated speeds.
Implementation Method 1
The coolant outlet is configured to disperse coolant in a curtain across the entire rake face of each cutting edge
Implementation Method 2
Using coolant provides lubricity, heat dissipation from the tool
Implementation Method 3
Using coolant provides lubricity, heat dissipation from the tool
Data Source
AI summary
There is provided a drill tool assembly for drilling metallic or other materials, comprising a holder having a mounting slot in which a cutting insert is positioned, and a through tool coolant supply system. The drilling tool system allows for the application of coolant to the rake surfaces of the cutting insert in a manner which facilitates enabling higher penetration rates while maintaining integrity of the cutting edges of the cutting insert. The drilling tool system comprises a holder having a rotational axis and mounting slot. A cutting insert with sides positioned adjacent the side surfaces of the mounting slot and cutting edges extending from the rotational axis is mounted in the slot. The insert includes rake surfaces adjacent the cutting edges that are positioned above the mounting slot. At least one coolant channel is disposed with at least one coolant outlet directed at the sides of the insert at a position below the rake surfaces. The coolant outlet is configured to disperse coolant in a curtain across the entire rake face of each cutting edge.