How a natural plant oil is transforming manufacturing sustainability while improving quality
In modern manufacturing, machining processes are no longer evaluated solely on production efficiency but also on their environmental impact. For decades, the manufacturing industry has relied on synthetic coolants that are not only expensive but also potentially polluting and hazardous to workers' health. Recent research shows that plant oils, particularly castor oil (Jatropha Curcas L), offer a revolutionary solution as natural lubricants in machining ST41 steel with carbide tools 1 .
Traditional synthetic coolants can contain harmful chemicals that persist in the environment for decades, while plant-based alternatives like castor oil are biodegradable within weeks.
These findings aren't just academic discourse—their implications simultaneously touch on economic, environmental, and production quality aspects. Imagine if manufacturing industries could reduce their carbon footprint without sacrificing product quality, possibly even improving it! This article will take you through how this often-overlooked castor plant oil can outperform conventional lubricants in terms of surface roughness and temperature control during steel turning processes.
Surface roughness measures the irregularities of a workpiece surface resulting from machining processes. Lower roughness values indicate smoother surfaces, directly affecting functional performance, wear resistance, and product aesthetics 5 .
During machining, mechanical energy converts to heat energy due to friction between tool and workpiece. Excessive temperature causes:
ST41 steel is a structural steel with tensile strength of 41 kg/mm², widely used in construction and industry due to its good formability, weldability, and heat treatment capabilities 3 .
Carbide tools offer high hardness, superior wear resistance, and ability to maintain properties at high temperatures 4 .
Research conducted by Suwarno Roy Adi (2019) used experimental methods with a quantitative approach to analyze the effect of castor oil variations as coolant in turning ST41 steel 1 . The study was carefully designed to ensure all variables were well controlled, except for the coolant variations being tested.
Castor oil was tested in several formulations:
This comparative approach allowed researchers to not only evaluate castor oil's effectiveness but also determine optimal formulations for practical applications 1 2 .
Results showed that castor oil significantly reduces surface roughness compared to conventional synthetic coolants. The mechanisms behind castor oil's effectiveness relate to:
These findings are consistent with previous research showing that coconut and canola oils in 15% oil + 5% meditran oil + 80% water formulations improved surface roughness quality by 12.3% and 18.6% respectively compared to synthetic coolant 2 .
In terms of temperature control, castor oil also demonstrated impressive performance. Using castor oil as coolant resulted in significant reduction in machining temperature compared to dry conditions or even some synthetic coolants.
This temperature reduction has important implications for:
| Coolant Type | Composition | Average Roughness (µm) | Reduction vs. Synthetic |
|---|---|---|---|
| Synthetic (Dromus) | 100% | 3.42 | - |
| Castor Oil | 100% | 2.81 | 17.8% |
| Castor Mix | 15J+5O+80A | 2.65 | 22.5% |
| Coconut Oil | 15K+5O+80A | 3.00 | 12.3% |
| Canola Oil | 15C+5O+80A | 2.78 | 18.6% |
| Parameter | Influence (%) | Significance Level |
|---|---|---|
| Coolant Type | 42.7 | p < 0.01 |
| Cutting Speed | 28.3 | p < 0.01 |
| Feed Rate | 18.5 | p < 0.05 |
| Depth of Cut | 10.5 | p < 0.05 |
Source: 1
Key materials used in research on castor oil as machining coolant:
| Material/Reagent | Function | Key Characteristics |
|---|---|---|
| Castor Oil | Primary coolant | High viscosity, high flash point, excellent biodegradability |
| Meditran Oil | Additive to improve adhesiveness | Enhances film strength, anti-wear properties |
| Water | Dilution medium to reduce viscosity | Lowers cost, improves cooling capability |
| ST41 Steel | Research workpiece | Tensile strength 41 kg/mm², easy to machine, wide applications |
| Carbide CCMT Insert | Cutting tool for turning process | High hardness, excellent heat resistance, superior wear resistance |
| Surface Roughness Tester | Measures surface roughness | High accuracy, multi-axis parameter measurement capability |
Findings on castor oil's effectiveness in machining ST41 steel open doors for various follow-up studies:
Research on using castor oil as coolant in machining ST41 steel with carbide tools not only proves the technical superiority of plant oils over synthetic coolants but also points the way toward more sustainable manufacturing industry. With an excellent combination of performance, economy, and environmental sustainability, castor oil and other plant oils have the potential to fundamentally change the machining industry landscape.
The challenge ahead is how to implement these research findings on a broader industrial scale, develop clear standards and protocols, and encourage wider adoption among manufacturing industries. Collaboration between academia, industry, and government will be key to realizing this green transformation without sacrificing productivity and product quality.
These research results are relevant not only to materials engineers and researchers but also to industrial policy makers, manufacturing practitioners, and even the general public who care about environmental sustainability. The green revolution in the machining world has begun, led by something unexpected: oil from the humble castor plant.