MQL Advantages – The Haas Minimum Quantity Lubrication System

Introduction to MQL in CNC Machining

Overview of Minimum Quantity Lubrication (MQL)

• Ander Harnett introduces the concept of Minimum Quantity Lubrication (MQL), a method that uses a fine oil mist delivered via air to lubricate cutting tools, contrasting it with traditional flood coolant systems.

• The discussion highlights the growing interest in MQL as an alternative lubrication system for CNC Mills, featuring applications engineer Matt Silva who explains its implementation.

Benefits of MQL Over Flood Coolant

• MQL is particularly beneficial when water-based coolants are unsuitable; it allows for significant reductions in lubricant consumption—up to five times less concentrate than flood coolant.

• Implementing MQL can potentially enhance tool life and performance, especially when paired with high-performance materials like carbide and aluminum titanium nitride.

Integration and Functionality of MQL Systems

Setup and Compatibility

• The integration of MQL with existing systems is seamless; it can be added on top of the auto air gun without disrupting regular flood coolant operations.

• Matt demonstrates how the high feed milling process combined with MQL helps manage heat effectively during machining, reducing thermal shock risks associated with traditional cooling methods.

Operational Insights

• One key advantage of using MQL is maintaining a stable tool temperature by minimizing frictional heat, which enhances tool longevity compared to conventional cooling methods.

• The flexibility of the auto air gun design allows easy retraction during tool changes or tight spaces, improving usability over stationary systems.

Setting Up and Adjusting the MQL System

Atomizer Configuration

• Proper setup involves adjusting the atomizer nozzle distance from the tool; typically set one to three inches away for optimal oil delivery.

• A common mistake is setting atomizers too rich; visibility of oil mist indicates excessive flow. Initial settings should be conservative to avoid waste.

Testing Oil Delivery

• Demonstrations show varying atomizer settings affecting oil deposition on cardboard, illustrating how adjustments impact lubrication effectiveness.

• Matt emphasizes that while lighter settings are often sufficient, heavier settings may lead to excess oil application that could hinder performance.

Applications Beyond Cutting: Tapping with MQL

Efficiency in Tapping Operations

• The use of MQL extends beyond cutting operations; it also proves effective for tapping processes by automating fluid delivery without manual intervention.

Control Mechanisms

Cutting Fluid Management and MQL Benefits

Overview of Cutting Fluid System

• The nozzle atomizer screw serves as a coarse adjustment for cutting fluid, while a separate mechanism allows for fine adjustments. This design is user-friendly, enabling easy daily checks on the reservoir levels.

• A reference list of approved oils is available, including some non-toxic options like mineral and canola oils. The current operation utilizes one of these recommended oils.

Oil Consumption in Machining

• The machine consumes approximately half an ounce of oil per hour during cutting operations, which is typical for Minimum Quantity Lubrication (MQL) applications.

• In contrast, the machine uses about 20 gallons of coolant weekly at a six percent concentration, requiring over a gallon of concentrate to produce this amount.

Cost Efficiency with MQL

• When using MQL, only about 10 ounces of oil are needed for 20 hours of cutting compared to significantly higher amounts when using traditional coolant methods.