The selection of pipe fittings requires comprehensive consideration of media characteristics (such as temperature, pressure, and corrosivity), installation environment (such as space constraints and vibration frequency), and cost factors. Internationally accepted standards include ASME (American Society of Mechanical Engineers), DIN (German Industrial Standard), and ISO (International Organization for Standardization), while domestic standards follow GB/T (National Standard) and HG/T (Chemical Industry Standard). For example, pipe fittings for conveying drinking water must comply with GB/T 17219 "Safety Evaluation Standard for Drinking Water Transmission and Distribution Equipment and Protective Materials" to ensure they are non-toxic and harmless; while high-temperature steam pipelines require alloy steel materials with higher temperature resistance.
