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Wear resistance: Each type of grinding has its own characteristics. Its properties determine the hardness and thickness of the coating required. In practical applications, please follow these rules: 1. If you are not sure or unable to conduct tests, remember that the thicker the coating, the better. 2. The wear of polyurethane does not follow an exponential pattern. If the coating thickness is doubled, its service life may be 4 to 6 times that of the original coating. 3. The wear resistance of polyurethane coatings in a mud environment is better than that in a dry friction environment. This is mainly because the mud acts as a cooling fluid for the polyurethane coating; the wear-resistant, corrosion-resistant, elastic polyurethane spray product retains the heat generated under dry friction conditions without releasing it. 4. Polyurethane protective coatings have a long history of being used to treat and support smaller components such as objects 6 mm or smaller. However, the polyurethane material developed by our company recently shows that its coating can also be used to handle silica with a diameter of up to 355 mm. 5. Polyurethane has a flexural modulus of 20%, and this factor needs to be taken into consideration during design for applications that are subject to loads. 6. In terms of wear resistance, rubber materials and polyurethanes are comparable. The wear resistance of other materials such as polyurea, epoxy resins, vinyl plastics, and other polymer coatings cannot compare to that of polyurethanes. Corrosion resistance: Polyurethanes exhibit good overall resistance to chemical corrosion, and this property is even more pronounced when submerged. In practical applications, please refer to the following rules: 1. The brittle fracture temperature of pure polymeric wear-resistant, corrosion-resistant elastic polyurethane spray products is -56°C. 2. The thermal insulation performance of polyurethane varies significantly depending on the type selected. Aliphatic series such as 3S, 5S, and 7S can withstand contact with objects at temperatures up to 100°C. Our company’s 95HT product can withstand temperatures of 173°C to 225°C when in contact with materials such as hot asphalt. 3. Unless otherwise specified, the resistance to chemicals charts are based on ambient temperature. The corrosivity of an acidic solution at 70°C is much greater than that at 21°C. In cases where wear-resistant, corrosion-resistant elastic polyurethane spray products are used in environments exposed to acidic substances, the temperature should not exceed 60°C. For temperatures above the above value, please consult our company. 4. The resistance of polyurethanes to chemical corrosion is expressed as a pH value ranging from 3 to 11. Testing is required when the pH value is on the boundary, such as between 2-3 or between 11-12. It is not recommended to use such products in environments where the pH value is below 2 or above 12. 5. Polyurethane coatings perform better in water, saline water, and desalinated water. 6. In most cases, the smoke emitted is more abundant than the actual liquid, and the liquid at the liquid-gas interface is more corrosive. 7. When the wear-resistant, corrosion-resistant, elastic polyurethane spray product is in water, it will continue to cure even after 18 hours of initial curing. 8. For applications in vacuum environments, allow the polyurethane coating 7 days to cure. This will give time for the bond between the wear-resistant, corrosion-resistant elastic polyurethane spray product and the substrate to form. 9. If there are doubts about the performance of polyurethane coatings in a certain chemical environment, test, test again, and test once more. Tests on polyurethanes can be conducted using a metal block that is completely enclosed by a polyurethane coating of a fixed thickness; one end of this metal block must have a hole with a width of at least 6 mm. After measuring the weight of the metal, place the hole-free end of the metal block in a chemical environment for 7 days. Then remove the metal block and weigh it again. If the weight variation of the metal block is below 5% (or equal to 5%), it can be assumed with 99% certainty that the performance of polyurethane in such a chemical environment is satisfactory. At the same time, visually inspect the coating surface for any irregularities. Noise resistance: 1. As a natural insulator, polyurethane also has the potential to reduce noise. Generally, the noise-reducing effect of softer coatings is better than that of harder coatings. 2. For our company’s 3S product, a 0.5mm thick coating can reduce noise by 7 decibels, while a 1mm thick coating can reduce noise by 14 decibels. This effect has been demonstrated in vibrating feeders. Electrical conductivity 1. Polyurethane is a natural insulator. The resistivity of cured polyurethane sheets with a typical thickness of 25μm ranges from 400 to 700 ohms. When the sub-thickness of the polyurethane coating after spraying is 25 μm, the resistivity reaches 13,000 ohms. 2. Antistatic materials can be implanted to reduce the resistivity of polyurethane. Flexural (impact) elastomeric polyurethane materials will deform but will not be compressed. Just like stepping into a puddle, the water moves to other places but its volume does not decrease. The wear-resistant, corrosion-resistant elastic polyurethane spray product can withstand a deflection of 20%. A deflection of more than 20% can lead to premature degradation of polyurethane materials. The higher the hardness of a polyurethane coating, the lower its deflection; the lower the hardness, the greater the deflection it can withstand. For example, a coating 25 cm thick can achieve a deformation of 5 cm, while a coating 250 μm thick can achieve a deformation of 50 μm. 1. The thickness of the coating for wear-resistant, corrosion-resistant elastomeric polyurethane spray products must be determined based on the actual conditions under which it will be used. Factors that affect the coating thickness include the size of the load material, the falling height, the material’s movement speed, the level of wetness or dryness, and the impact angle. Our company can provide recommendations regarding coating thickness based on the specific circumstances; please contact us if you need such advice. 1. According to the classification of flame spread and smoke production levels specified in ASTM E-84, the flame spread rating for polyurethanes is usually below 40, with smoke production typically below 30. 2. Flame retardants can be added to polyurethane spray coatings that are designed as wear-resistant and corrosion-resistant elastomers in order to improve their fire resistance. Both solvent-based and solid polyurethane spray products can be infused with flame retardants and possess self-extinguishing properties in certain cases. Color retention capacity: 1. Unless otherwise specified in the design and manufacturing process, wear-resistant, corrosion-resistant elastic polyurethane spray products will yellow over time. Due to the presence of amine components in the cured product series, polyurethanes will fade or turn yellow. However, we have produced 3SV products for spraying on outdoor items, or as topcoats for our amine-hardened products to prevent fading. 2. All of our company’s wear-resistant, corrosion-resistant elastomeric polyurethane spraying products can have a topcoat applied to their surface in order to maintain color stability; these topcoats can be outdoor polyurethane paints or our own 3SV product.