Determination of Dry Coatings - caimateriali.org

Determination of Dry Coating Effectiveness Against Water impregnation. An examination of various testing methods. William J. (Bill) Fronzaglia P.E. Director of Engineering New England Ropes, Inc. 848 Airport Road Fall River, MA 02720 USA Phone: 508-678-8200 / 800-333-6679 Fax: 508-679-2363 / 800-647-6731 www.neropes.com UIAA Journal 2/2001 Pg. 25

Available at WWW.UIAA.CH Definition dry (dri) adj. Etymology: Middle English, from Old English dryge; akin to Old High German truckan dry, Old English drEahnian to drain Date: before 12th century free or relatively free from a liquid and especially water 1a: b : not being in or under water c : lacking precipitation or humidity

Fact: By Definition: Reduced water impregnation will reduce weight gain. Assumption: Keeping water out will keep performance up Proper care and handling to reduce unnecessary water exposure is best 1st choice. Behavior of Nylon when Wet.

Weight Gain Decrease of tensile strength by 10% - 15% Decreased resistance to Yarn on Yarn Abrasion. Reduced Elongation Increased Impact force Decreases number of drops sustained. Increased diameter Increased risk! Yarn Finish/Coating Technology

Spin Finishes Marine Overlay Finishes Wax Emulsions Mineral Oil based products Silicone Multi part polymer coatings Proprietary coatings Dying process removes beneficial finishes Benefits of coating

Improved Hydrophobic properties Improved Yarn on Yarn Abrasion Resistance Improved Yarn on Metal Abrasion Resistance Decreased Internal Yarn on Yarn Friction Reduction of dirt impregnation Increased Life? Manufacturer Claim Manufacturer Claim Manufacturer Claim Manufacturer Claim

Manufacturer Claim Manufacturer Claim Manufacturer Claim Manufacturer Claim Alternate Test Methods Water Droplet Test Flotation / Buoyancy Test. Shower Test Mammut

German Military Standard Test TL 4020-0015 (BWB) Dynamic Ropes. Method A Method B (72 Hour Immersion) U.S. Fed. Test Method Std. No. 191A Method 4500 Method 6011 (24 Hour Immersion) 1, 2, 4, 24, 48, 72 Hour Immersion Test Parameters U.S. FED-STD-191A (6011) Sample Preparation Length of sample Sealing of ends

Water Specifications Ph Hardness Temperature Methodology Wetting Method Test Duration (Hours) Drainage Method Weighing of Sample German TL 4020-0015 Method B 15" 200mm No Yes (Store Bought Distilled Water was used for all tests)

7 7 0 0 21C - 70F 21C - 70F Immersion Test Shower Test 200mm Yes 200mm Yes

7 0 21C - 70F 7 0 21C - 70F 18 l/m shower 2.5 Min. Shake excess/weigh immediately Nearest 0.001g 9" submerged in loop 24 Hours Placed in 75mm H20

72 Hours Placed in 75mm H20 1, 2, 4, 24, 48, 72 Hours 1.5 Hours (Rack) 500g weight-3 Min. 3 Min. (Rack) Nearest 0.001g Nearest 0.001g Nearest 0.001g

Results of testing. Water Absorption 0.60 0.50 A B 0.40 C D E F 0.30 G

H I J K 0.20 L M 0.10 0.00 Shower Test 1 Hour 2 Hour

4 Hour 24 Hour 48 Hour 72 Hour Results of testing. Water Absorption 0.60 0.50 A B 0.40

C D E F 0.30 G H I J K 0.20 L

M 0.10 0.00 FED-STD-191A (6011) 24 Hour Immersion Results of testing. Water Absorption 0.60 0.50 A B 0.40

C D E F 0.30 G H I J K 0.20 L M

0.10 0.00 72 Hour Immersion TL 4020-0015 - Method B What happens if the rope is washed? Results of testing. Water Absorption 0.70 0.60 A

0.50 B C D E 0.40 F G H 0.30 I J

K L 0.20 M 0.10 0.00 1 Hour Immersion 1 Hour Immersion (After wash) Results of testing.

Water Absorption 0.70 0.60 A B 0.50 C D E 0.40 F G

H 0.30 I J K 0.20 L M 0.10 0.00 FED-STD191A (6011)

1 Hour Immersion 2 Hour Immersion 4 Hour Immersion 24 Hour Immersion 48 Hour Immersion 72 Hour

TL 4020-0015 1 Hour Immersion - Method B Immersion (After wash) Conclusions All dry coatings are not equal. Ropes with better performance perform better in all tests. Some ropes have a barrier which allows them to float, this barrier is very fragile. These tests only address weight of water absorbed, not performance when wet. Conclusions Best Test Method

Standard length samples. Hold sample submerged to prevent surface tension effect. 1 hour duration, Longer is not necessary. Drain on rack for 3 min. Further Study Required Decrease in performance of nylon ropes vs. % of moisture gained. Real world exposure. Which method is most realistic?