| Materials Heat Resistance Test |
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A simulation test was done in early Jan. 2007 to evaluate inner fabrics and heating element insulation used to fabricate KM-EL flexible heating jackets. Objectives of the test were to see:
1.to what temperature level can the inner fabrics and the heating element insulation can resist and;
2.he extent of smell and amount of off-smoke that will be generated by the fabrics and elements |
| Briefing of the test: |
| Materials/construction of the KM-EL (0.5W/cm2, 960W) sample (for 2” pipe): |
1.heating element insulation: braiding of fiberglass yarn with proprietary coating, 650℃ temperature ratin
2.Inner fabrics, 3 sections by fabric material of: |
| section 1: WHITE COLORED # 3-33P/P(PTFE coated fiberglass cloth) |
| section 2: WHITE COLORED Nomex fabric (continuous filament) |
| section 3: WHITE COLORED #08-20F/P(100% high strength PTFE) |
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3.Outer fabrics: (gray colored PTFE coated fiberglass cloth)
4.
Insulation Blanket: smoke-less KM600 fiberglass blanket, 10mmt
5.Heating elements of the 3 inner sections were serially connected
6.No thermostat and or thermo-fuse was used
7.Heating element; 2.75 Ohm/m
8.Power: 220VAC
9.Ambient temp: 20°C, 0m/sec wind velocity |
Procedure of the test: |
1.one K-thermo-couple was installed at each inner section respectively, totalling 3 thermo-couples
2.the 3 thermo-couples were all connected to gauge for temperature readings
3.KM-EL was heated up by heating schedule as below: |
Ambient 20℃ to 250°C in 10 minutes, Stay at 250°C for 4 hours ------------A
Increase from 250°C to 350℃ in 15 minutes, Stay at 350°C for 4 hours-------------B
Increase from 350°C to 400℃ in 10 minutes, Stay at 400°C for 4 hours-------------C
Increase from 400°C to 450℃ in 13 minutes, Stay at 450°C for 4 hours.-------------D |
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| 4.at end of stage A, B, C, D, inner fabrics and elements were carefully inspected for flexibility, strength and integrity. |
Results: |
Pictures were taken at end of stage A, B, C, D. as followings: |
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Observations and Conclusions: |
1. Nomex fabric started to carbonized and get brittle at 250°C
2. Nomex fabric carbonized completely at 350°C losing all of its integrity and strength
3. # 08-20F/P remained intact and white color up to 350°C. It melted at 400C and started to vaporized.
4. #3-33P/P remained strong and flexible up to 450°C,
5. very minimum (rarely observed) smoke or smell developed during the test
6. heating element insulation stayed in good conditions with good residual flexibility and strength to 450°C. |
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