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Does your piping system leak after experiencing hot and cold cycles? Unplanned downtime and maintenance make costs out of control? Frequent re-tightening of bolts consumes a lot of man-hours? The failure of traditional flanges to seal under dynamic conditions is a common but expensive pain point in industrial processes. The Convex Flange produced by Longan perfectly solves this problem. It has multiple advantages: 1. It can withstand high temperature and high pressure 2. It is simple and convenient to install, and the efficiency is significantly improved 3. The sealing adaptability is very strong 4. The product is lightweight and the material utilization efficiency is high

Longan is a professional manufacturer of Long Neck Flanges. We will provide you with thoughtful after-sales service and prompt delivery. Long neck weld flange is a weld neck flange with an extended neck, which is used in high pressure and high temperature environments. This unique design can be used as an extension of the boring hole to provide reinforced connections in harsh environments. The products are mostly used in industries such as oil, gas and petrochemicals.

You can rest assured to buy Long’an 304 Alloy Steel Forged Butt Welding Flange from our factory.The manufacturing process of this flange includes the selection of high-quality billets, heating, forming, forging and cooling in the forging process. Normalizing, annealing or quenching + tempering treatment is carried out to optimize the material properties. Surface treatment options include galvanizing, hot-dip galvanizing, painting, anti-rust oil, etc.

304 stainless steel flanges have a super cost-effectiveness and are the choice of most general industrial pipelines.
304 stainless steel flanges have various types, including blind plates, butt-welded necks, loose sleeves, threaded types, etc., and the chromium-nickel content is ≥18/8% verified by XRF. The service life in ordinary environments (pH>4.5) is more than 10 years, which is 400% higher than carbon steel. However, the cost is 35% lower than that of 316 flanges.

304 welding flange complies with ASME B16.5 standard, and the pressure covers Class 150~900. After 500 hours of salt spray test, the service life of carbon steel flange is increased by 400%, and the cost is 30~35% lower than that of 316 flange.

304 Neck Butt Welding Flange is suitable for non-extreme corrosion scenarios such as water treatment, HVAC, and food equipment. The product provides corrosion resistance in oxidizing environments through 18% chromium + 8% nickel components, complies with ASME B16.5 standards, and covers pressures from Class 150 to 900. Verified by a 500-hour salt spray test, the life of carbon steel flanges is increased by 400%, and the cost is 30 to 35% lower than 316 stainless steel. ASTM A182 material certification and dimensional accuracy reports are also provided.