Twin-Path® Slings Environmental / Chemical Considerations
When not in use, synthetic slings should be stored in a clean dry place. Heat sources and non-ventilated places should be avoided.
Chemically active environments can affect the strength of synthetic lifting slings. Different chemicals will react different exposure to Covermax™ bulked nylon, polyester, aramids, and Olefins. (Please see the enclosed tables for reactions of specific chemicals.)
Aramids are resistant to most ketones, alcohols, dry cleaning solvents and many other organic solvents. Its acid resistance is superior to that of nylon but is not as good as that of polyester. Aramids show good resistance to alkalis at room temperature, but is degraded by strong alkalis at higher temperatures.
Aramids are compatible with fluorine-containing elastomers, resins, and refrigerants at high temperatures, and is resistant to fluorine compounds in concentrations usually encountered in stack gases from metallurgical and rock-processing operations.
The resistance of aramids to oxides of sulphur at temperatures above the acid dew point is superior to that of polyester. Below the dew point, concentrated sulphuric acid may condense on the fiber and cause a progressive loss in strength.
In moderate to strong acid or alkali environments, evaluation of aramids should be made to ensure that the yarn will perform acceptably before use.
Polyester and nylon are not significantly affected by most compounds of the following classes:
- Alcohols
- Dry Cleaning Hydrocarbons
- Ketones
- Soaps and Synthetic Detergents
- Water (Including Sea Water)
Polyester also shows good to excellent resistance to:
- Aqueous solutions of most weak acids at the boil, and to most strong acids at room temperature, but is disintegrated by concentrated (95%) sulphuric acid at room temperature.
- Aqueous solutions of strong alkalis at room temperature, but is degraded at the boil.
- Oxidizing agents, and is not degraded by bleaching treatments ordinarily used for textiles.
Nylon is not significantly affected by most aldehydes, alkalis, ethers, or hydrocarbons, but is deteriorated by dilute acids (e.g., hydrochloric acid and sulphuric acid in 10% concentrations at room temperature cause a noticeable loss in breaking strength in 10 hours).
Solvents for nylon include:
- Concentrated formic acid
- Phenolic compounds at room temperature
- Calcium chloride in methanol at room temperature
- Hot solutions of calcium chloride in:
Glacial Acetic Acid
Ethylene Chlorohydrin
Ethylene Glycol
- Hot solutions of calcium chloride in:
Glacial Acetic Acid
Ethylene Chlorohydrin
Ethylene Glycol
- Hot solutions of zinc chloride in:
Methanol Benzyl Alcohol at the boil
Aramids are resistant to most weak acids and alkalis, ketones, alcohols, hydrocarbons, oils and dry cleaning solvents. Strong acids and bases and sodium hypo-chlorite bleach attack aramids, particularly at high temperatures of high concentrations.
K-Spec™ core yarn strength retention is based on test results of components at 65°C/150°-F (or less) for 6 months. K-Spec™ has a 100% strength retention when exposed to: Age, 10% detergent solution, rot and mildew, sunlight and Toluene; 99% strength retention when exposed to: acetic acid, gasoline, hydrochloric acid 1m, hydraulic fluid, kerosene, and sea water; 98% retention when exposed to: 25% ammonium hydroxide, 10% hypophosphite solution, and 40% phosphoric acid; 97% retention when exposed to 5m sodium hydroxide; 95% retention when exposed to Portland cement and sulfuric acid; and 88% retention when exposed to Clorox®, and nitric acid.
