Why the Fiber Core Materials with Excessive Water-Soluble Acid Content Are Not Suitable for Elevator Steel Wire Ropes ?
According to China national standards such as ‘Elevator Manufacturing and Installation Safety Code’ and ‘Elevator Steel Wire Rope,’ the materials used for elevator steel wire ropes need to have good resistance to chemical corrosion to ensure their stability and safety under various environmental conditions. The choice of elevator rope core material is crucial for the safe operation of elevators. Fiber core materials with excessive water-soluble acid content are not suitable for elevator steel wire ropes, mainly for the following reasons:
1. Corrosive Impact: Materials with excessive water-soluble acid content have strong corrosive properties, which may lead to corrosion of the core and the steel wire rope itself, thereby reducing its mechanical properties and durability.
2. Reduction in Lubrication Protection: One important function of the rope core is to store lubricating oil, providing lubrication and protection for the steel wire rope. If the rope core material has excessive water-soluble acid content, it may cause premature loss of lubricating oil, leading to dry friction during the operation of the steel wire rope, accelerating wear, and even causing wire breaks.
3. Increased Safety Risks: Due to the reduced mechanical properties of the steel wire rope caused by excessive water-soluble acid content in the material, this increases the safety risks during elevator operation, such as steel wire rope breakage and other serious accidents.
In summary, rope core materials with excessive water-soluble acid content are not suitable for manufacturing elevator steel wire ropes due to their corrosive nature, reduced lubrication protection and increased safety risks.
The Standard For the Water-Soluble Acid Content In the Core of Elevator Steel Wire Ropes
According to the ISO 4345:1988 international standard, the standard for the water-soluble acid content in the core of elevator steel wire ropes is as follows:
1. Determination of Water-Soluble Acid Content: The water-soluble acid content in the core of elevator steel wire ropes should not exceed 2 milliliters of a 0.1 molar/liter acid solution per 100 grams of core (≤2ML/100g). This standard ensures the chemical stability of the core material to guarantee its stability and safety under various environmental conditions.
2. Testing Method: To test the water-soluble acid content, a sample of approximately 20 to 30 grams should be taken from the core to be tested and accurately weighed. The sample is then placed in a Soxhlet extractor, boiled with 100 milliliters of distilled water for 30 minutes, filtered through filter paper, and the residue is washed three times with hot distilled water. After washing, the total volume of the water extract should not exceed 175 milliliters. A few drops of phenolphthalein are added to the extract, and the solution is titrated with a 0.1 molar/liter standard volume of sodium hydroxide or potassium hydroxide solution until a permanent pink color is achieved.
3. Result Expression: The water-soluble acid content should be expressed in milliliters per 100 grams of sample (ml/100g) and should be accurate to 0.1 milliliters.
These standards ensure the requirements for the chemical stability of the core material of elevator steel wire ropes, reducing the risk of corrosion and improving the safety and reliability of elevators.
