Ceramic Drilling Layout That Uses Gravity to Clear Back-Splash

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Efficient machining of deep, small-diameter holes in ceramic matrix composite (CMC) materials for gas turbine engines is challenging due to poor surface integrity, high tool wear, and low productivity with existing methods like drilling, grinding, laser, and abrasive waterjet machining.

Innovation Solution

A method and system utilizing a drilling machine with a jet head that impinges a liquid stream containing abrasive particles or a laser beam onto the target region, with the liquid stream rebounding and being gravitationally drained to reduce interference, and the jet head moving in a controlled manner to scan the target region in spiral patterns or layer-by-layer according to a 3D model, facilitating efficient material removal.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If traditional drilling, grinding, laser, or abrasive waterjet machining is used on CMC materials, then holes can be formed in the ceramic material, but the process suffers from poor surface integrity, high tool wear, and low productivity

Engineering Contradiction:
Improvesurface integrityVSAvoidmachining efficiency
Core Design Contradiction:
Manufacturing precisionVSProductivity

Solution Approach 1:

The machining process segments the liquid stream into discrete abrasive particles or laser pulses that impact the material sequentially, allowing controlled material removal while maintaining surface integrity. The spiral scanning pattern further segments the cutting action into incremental passes rather than continuous contact.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The jet head moves in a spiral scanning pattern with periodic impingement cycles, allowing the liquid stream to repeatedly impact the same region in a controlled manner. This periodic action enables progressive material removal while maintaining consistent surface quality and reducing thermal buildup.

Inventive Principle:
Principle #19Periodic action

2Productivity

If a liquid stream is jetted at the target region to remove material, then machining can be performed, but the back-splash liquid interferes with the liquid stream and reduces machining efficiency

Engineering Contradiction:
Improvematerial removal rateVSAvoidback-splash interference
Core Design Contradiction:
ProductivityVSObject-generated harmful factors

Solution Approach 1:

The harmful back-splash liquid is extracted and removed from the machining zone by positioning the target region vertically above the jet head. Gravity causes the rebounded liquid to drain away from the interaction zone, preventing it from interfering with the incoming liquid stream and maintaining machining efficiency.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The vertical positioning creates a gravitational potential gradient that naturally drives the back-splash liquid away from the machining zone. By aligning the target region at a higher vertical position than the jet head, the system utilizes gravity to continuously clear rebounded liquid without requiring additional active removal mechanisms.

Inventive Principle:
Principle #12Equipotentiality

3Manufacturing precision

If deep, small-diameter holes are drilled in CMCs, then cooling features can be created for turbine components, but existing machining methods exhibit high tool wear and low productivity

Engineering Contradiction:
Improvehole geometry controlVSAvoiddrilling speed
Core Design Contradiction:
Manufacturing precisionVSProductivity

Solution Approach 1:

The system dynamically adjusts the spiral scanning pattern and liquid stream parameters during machining of deep, small-diameter holes. The jet head continuously moves along a spiral trajectory while maintaining optimal positioning, enabling controlled material removal through the entire hole depth without tool wear associated with traditional drilling.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

Traditional mechanical drilling and grinding tools are replaced with a liquid stream-based system that uses abrasive particles or laser energy transmitted through liquid. This substitution eliminates mechanical tool wear while maintaining the ability to create precise deep holes in brittle CMC materials.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

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 approach enhances the efficiency of hole machining in CMCs by minimizing interference from back-splash liquid, reducing tool wear, and increasing productivity, allowing for precise formation of tapered and uniform sections in cooling holes.

Implementation Method 1

The liquid stream contains either abrasive particles or a laser beam. The liquid stream impinges the target region and the abrasive particles or the laser beam cause removal of material from the component at the target region

Methodology Applied
Scientific EffectAbrasion: Abrasion

Implementation Method 2

The liquid stream contains either abrasive particles or a laser beam. The liquid stream impinges the target region and the abrasive particles or the laser beam cause removal of material from the component at the target region

Methodology Applied
Scientific EffectLaser ablation: Laser Ablation

Implementation Method 3

The liquid stream rebounds off of the component as back-splash liquid, and the drilling arrangement causes gravitational draining of the back-splash liquid from the target region

Methodology Applied
Scientific EffectGravity: Gravitation

Data Source

PatentEP4137271A1Method and system for drilling ceramic material
Publication Date: 2023.02.22 RTX CORP
  • EP4137271A1 patent drawingFigure 1
  • EP4137271A1 patent drawingFigure 2~3
  • EP4137271A1 patent drawingFigure 4

AI summary

A method of machining includes mounting a component in a drilling machine. The component has a target region where the hole is to be drilled. The component and a jet head are situated relative to each other in a drilling arrangement in which the target region is at a first position that is vertically equal to or vertically above a second position at which the jet head is located. A liquid stream is jetted from the jet head and contains either abrasive particles or a laser beam. The stream impinges the target region, and the abrasive particles or the laser beam cause removal of material from the component to form the hole. The liquid stream rebounds off of the component as back-splash. The drilling arrangement causes gravitational draining of the back-splash from the target region to reduce interference between the back-splash and the liquid stream.