Advantages of Hastelloy Tuning Fork Level Switch
The tuning fork level switch is a highly reliable control switch specifically designed for liquid level measurement. It is suitable for measuring the level of liquids in containers, storage tanks, and vats, as well as monitoring the flow of liquids in pipelines. In industrial processes, certain chemical raw materials may have hazardous properties such as toxicity, corrosiveness, flammability, or explosiveness. These properties are critical to process safety. Therefore, understanding and managing these characteristics is key to ensuring the safety of production processes. A crucial part of this is selecting the right material for level measurement instruments used to monitor the level in containers storing these chemicals, to prevent corrosion of the probe body over time, which could lead to instrument failure and disrupt normal production.
This article discusses the material selection for tuning fork level switches, with a focus on the advantages of using Hastelloy probe material.
The probe materials for Ring-11 tuning fork level switches typically include 316L stainless steel, coated versions, and Hastelloy C22. These three materials can meet the measurement requirements in the majority of environments.
316L stainless steel is a low-carbon austenitic stainless steel containing chromium, nickel, and molybdenum. Thanks to the addition of molybdenum, 316L stainless steel offers excellent corrosion resistance, particularly in terms of pitting resistance, which is superior to 304 stainless steel. It performs well in various corrosive media, including seawater, chemicals, dyes, paper, oxalic acid, and fertilizers. Additionally, 316L stainless steel maintains relatively high strength at elevated temperatures, making it superior to 304 stainless steel in high-temperature environments.
Corrosion-resistant coatings are a technology used to apply specific materials to the surface of an object to isolate it from corrosive media. The main function of the coating is to prevent the object from corrosion. It effectively isolates the metal from corrosive media, thereby extending the object’s service life. The coatings exhibit strong resistance to acids, alkalis, salts, and chemical solvents, significantly improving the corrosion resistance of the metal substrate. They also offer protection against chloride and chlorinated environments, allowing the metal to work in harsh conditions involving temperature, pressure, and chemical media. However, the downside of corrosion-resistant coatings is that they may degrade, peel off, or fail over time, requiring regular inspection and maintenance to ensure their continued effectiveness. Additionally, corrosion-resistant coatings may fail if subjected to mechanical forces such as friction or impact.
Hastelloy materials are available in various types, with C-276, C-4, and C-22 being the most common. Among them, Hastelloy C22 offers the best overall performance, outperforming 316L stainless steel in several areas. Hastelloy C22 is a high-performance nickel-based superalloy with excellent corrosion resistance and mechanical properties. Its tensile strength is approximately 690 MPa, and its yield strength is around 283 MPa, providing high strength and toughness to withstand high stresses and heavy loads. Hastelloy C22 excels in corrosion resistance, particularly in various aggressive environments such as strong acids, alkalis, and organic solvents. It shows strong resistance to uniform corrosion in both oxidizing and reducing environments, excellent resistance to pitting and crevice corrosion in chloride-containing environments, and high resistance to stress corrosion cracking under high-stress conditions. It also performs exceptionally well in highly concentrated chloride solutions like ferric chloride and copper chloride and is one of the few materials capable of resisting corrosion from wet chlorine, hypochlorite, and chlorine dioxide solutions.
Due to its excellent properties and wide range of applications, Hastelloy C22 has become an indispensable material in modern industry. It is widely used in the manufacture of chemical reactors, storage tanks, and pipelines, as well as in flue gas desulfurization units, wastewater treatment equipment, seawater desalination devices, offshore structures, and underwater pipelines. In nuclear power and conventional power industries, it is used to manufacture equipment for high-temperature, high-pressure corrosive environments, such as heat exchangers and steam generators. This material is especially suitable for use in high-temperature environments, as well as in environments exposed to impurities in inorganic and organic acids and seawater.
The Ring-11 tuning fork level switch probe made from Hastelloy C22 offers outstanding corrosion resistance and high-temperature resistance. It effectively addresses the issue faced by users when using coated tuning fork level switches in high-temperature environments, where the protective coating can peel off or degrade over time, leading to a reduction in corrosion resistance and a shortened service life. Hastelloy C22 probes can perfectly replace coated versions, filling a gap in the domestic market.
In summary, Hastelloy C22, with its exceptional corrosion resistance and mechanical properties, is widely recognized and applied in many industries. It is extensively used in water conservation, chemical, environmental protection, food, and pharmaceutical industries.