Details for purchasing electric heating systems and explosion-proof electric heating eye wash stations

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Since the purchasing departments of many projects in industries such as petrochemicals are unaware of some of the key details to consider when purchasing explosion-proof electric heat-traced eyewash stations, the following analysis is provided on these key aspects related to selecting such devices. The role of the casing material for explosion-proof electric heating eye washers: It has a direct impact on the performance of these eye washer products. After comparing the six materials – PPR, PVC, PE, ABS, stainless steel, and aluminum alloy – in terms of corrosion resistance, weather resistance, antistatic properties, detachability, cost, and service life, a comprehensive analysis indicates that ABS is the best material for the casing of explosion-proof electric heating eye washers. Testing of explosion-proof electric heat tracing eyewash stations: If necessary, the manufacturer is required to send a video showing the testing process of these eyewash stations; pay close attention to the steps involved in the testing. The testing should be carried out at an environmental temperature below 0 degrees Celsius. 1. When turning on the eyewash switch, gently push the eyewash handle; it may be impossible to open it in such cases. If this happens, hot water must be used to melt the ice inside the eyewash valve – do not force it open, as this could damage the valve. 2. When turning on the spray switch, gently pull the spray lever; it may also be impossible to open it. If this occurs, hot water should be used to melt the ice inside the spray ball valve – do not force it open, as this could damage the valve as well. 3. Check the connections of the eyewash unit for any signs of leakage. If leakage is detected, the eyewash unit must be repaired immediately. According to the specifications set by the design agency regarding the materials used for eyewash units, stainless steel SS316, stainless steel SS304, galvanized pipes, carbon steel pipes, and plastic pipes can all be used. When purchasing an explosion-proof electric heating eye washer, it is also important to understand the criteria used to select the materials for such devices: the flushing fluid used in the eye washer should not cause corrosion to the materials of the device. Under normal circumstances, the outer material of an explosion-proof electric heating eye washer is ABS engineering plastic, while the internal pipes are made of SS304 engineering steel. It is generally important to ensure that the chemicals present in the environment where the eye washer is installed do not cause external corrosion to the materials of the eye washer. Requirements for the strength of explosion-proof electric heat tracing eyewash stations: Eyewash stations must meet the strength requirements determined based on the conditions of the installation site. For example, eyewash stations installed by the sea must be able to withstand wind forces of level 9. Most manufacturers of eyewash stations use stainless steel as the material for their products. Put simply, stainless steel is steel that does not rust easily; in fact, some types of steel possess both rust resistance and acid resistance (corrosion resistance). The rust resistance and acid resistance (corrosion resistance) of stainless steel are due to the formation of a chromium-rich oxide film (passivation film) on its surface. Experiments have shown that in weak media such as air and water, as well as in oxidizing media such as nitric acid, the corrosion resistance of steel increases with increasing chromium content in the steel. When the chromium content reaches a certain percentage, its corrosion resistance undergoes a sudden change – from being prone to rusting to being less prone to it, and from being non-corrosion-resistant to being corrosion-resistant. Of course, different manufacturers use stainless steel in varying ways: some substitute substandard 304 stainless steel for standard-grade 304 stainless steel, while others use food-grade 304 stainless steel or 316 stainless steel. Since substandard stainless steel has a lower nickel content, its price differs significantly from that of compliant 304 stainless steel; however, its corrosion resistance is far inferior to that of compliant 304 stainless steel. In addition, attention should be paid to the requirements regarding eye wash nozzles: the flow rate of the eye wash solution must be greater than 1.5 L/MIN, while the flow rate of the water used for eye washing and face washing must be greater than 11.4 L/MIN. These are the basic requirements for the flow rate of eye wash water.