In the field of seawater desalination, the corrosion resistance and long-term reliability of components directly affect the equipment's operational lifespan. A seawater desalination parts factory in Zunyi, Guizhou, faced challenges such as insufficient material stability and large delivery cycle fluctuations when selecting stainless steel forging suppliers. As a professional stainless steel forging manufacturer, our company (Jianing Forging) relies on mature hot and cold processing technologies to provide customized stainless steel forging solutions for this customer, helping products maintain continuous use in environments with high sea salt concentration and high humidity.

Case Background and Customer Needs

The forgings originally used by the seawater desalination parts factory exhibited pitting and stress corrosion cracking in chloride-containing environments, and the dimensional consistency between batches was poor, leading to a decline in the pass rate of subsequent machining processes. The customer urgently needed a stainless steel forging with high pitting resistance equivalent (PREN), uniform mechanical properties, and stable supply to meet the assembly requirements of key components such as seawater desalination pump valves, flanges, and more.

Customized solutions

To address customer pain points, our company optimizes three aspects: material selection, forging process, and subsequent processing:

• Material selection: Uses low-carbon duplex stainless steel and 316L series, strictly controlling chromium, nickel, and molybdenum content to enhance resistance to pitting and crevice corrosion.
• Forging process: Using multi-directional forging and temperature-controlled forging, the grain structure is refined and internal looseness and segregation eliminated, resulting in the internal density of the forgings reaching a high industry level.
• Post-treatment and inspection: combined with solution treatment, pickling passivation, and ultrasonic flaw detection, it helps prevent cracks and inclusions, with surface roughness controlled below Ra0.8μm.

Delivery and results

Since mass supply began, the customer reported that the forging pass rate has increased by about 12% compared to before, and the sealing surface leakage rate after assembly has decreased. At the same time, by optimizing production scheduling and inventory management, our company stabilized the delivery cycle for regular orders at 20 to 25 working days and shortened urgent orders to within 15 working days, effectively supporting customers' production plans.

Continuous improvement and collaboration

Our company is equipped with dedicated technical coordinators who can adjust forging ratios, allowances, and heat treatment parameters according to customer drawings, and provide material certification reports and third-party testing data. Currently, the factory has included stainless steel forgings in the qualified supplier directory, and in the future, the two parties will further cooperate in the field of next-generation high-pressure seawater desalination pump parts.