1 Introduction
Fastener | Technology | Material | Surface finish | Lubrication | Diameter |
---|---|---|---|---|---|
Bolt | 64 | 4 | 6 | 4 | 26 |
Nut | 65 | 5 | 7 | 6 |
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Mixed level DOEs, with as many factors as desired, each factor taking the number of levels necessary for proper execution of the study;
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Box-Behnken DOEs [8], which respect the rotational isovariance criterion;
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Rechtschaffner DOEs [9], simplified fractional DOEs which allow the effects of factors and second order interactions to be determined;
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Taguchi DOEs, based on the most famous theory for quality, which allow the effects of factors and interaction to be determined.
2 Experimental Campaign
EN6115 – Screws | ||||
---|---|---|---|---|
Code | Material | Surface finish | Lubrication | Diameter range |
T | Titanium alloy 6AL – 4 V \({R}_{c}min=650\, {\text{MPa}}\) | Sulfuric-acid anodizing | Cethyl alcohol | 3(4.76 mm) 3A (5.56 mm) 4 (6.35 mm) |
V | Ion Vapour Deposition of aluminium | |||
K | Resin based Aluminium coating |
ASNA – Nuts | ||||
---|---|---|---|---|
Code | Material | Surface finish | Lubrication | Diameter range |
2528 | Aluminium alloy | Anodizing as per MIL-A-8625 | Cethyl alcohol | 3(4.76 mm) 3A (5.56 mm) 4 (6.35 mm) |
2529 | Anodizing as per MIL-A-8625, Type II, class 2 | |||
2537 | Nut: Aluminium alloy | Anodizing as per MIL-A-8625 | Cethyl alcohol | |
Washer: Corrosion Resistance steel | Cadmium plating | None |
3 Taguchi Factorial Experiment Plan
Tests | Screw surface finish | Type of nut | Diameter |
---|---|---|---|
1 | 1 | 1 | 1 |
2 | 1 | 2 | 3 |
3 | 1 | 3 | 2 |
4 | 2 | 1 | 3 |
5 | 2 | 2 | 2 |
6 | 2 | 3 | 1 |
7 | 3 | 1 | 2 |
8 | 3 | 2 | 1 |
9 | 3 | 3 | 3 |