GSHA/type series Hastelloy C-276 high-pressure reactor

Adopting end face rare earth coupling driver, it has the characteristics of static sealing and no leakage. The main material used for the kettle body isHastelloy C-276 alloy

, and can be made according to different media requirements304、321The316L、2520、Stainless steel and titanium materials(TA2)Nickel material, tantalum material, zirconium material, Hastelloy alloyMonelInner lining made of special materials such as polytetrafluoroethylene. The stirring bearing adopts corrosion-resistant stainless steel bearing, suitable for high-speed, hydrogenation catalysis, and low viscosity material stirring. The stirring blade adopts a push type stirring slurry. The heating method is generally dry electric heating, but electric heating, thermal oil heating or jacket heating can also be made according to user requirements. Equipped with a multifunctional temperature control and pressure control digital display control box. The heating control system adoptsPIDAutomatic temperature control instrument, temperature control is very precise. After tuning, the instrument can effectively suppress temperature overshoot.

Note:
In addition to the above specifications of finished products, different volume products can also be customized according to user requirements.
2. The conventional main material is 1Cr18Ni9Ti: 316L stainless steel, nickel, titanium, tantalum can be selected as the main material according to user requirements
Materials, zirconium, Hastelloy, MonelSpecial materials such as 2520.904L.
3. Electric heating, thermal oil heating, or jacket heating can be made according to user requirements.
4. The form of the stirring blade can be selected and customized according to user requirements.

Note: The supporting pipes, valves, measuring and display facilities can be configured according to the following sketch.

Process diagram of supporting equipment for reaction kettle experiment

Hastelloy reaction device

Hastelloy C-276 alloy

1、 Physical performance

Density:8.90g/cm3, Specific heat: 425J/kg/k, elastic modulus: 205Gpa (21 ℃)

2、 Corrosion resistance performance

HashiC-276 alloy belongs to the nickel molybdenum chromium iron tungsten series nickel based alloys. It is the most corrosion-resistant type of modern metal material. It is mainly resistant to wet chlorine, various oxidizing chlorides, chloride salt solutions, sulfuric acid and oxidizing salts, and has good corrosion resistance in low and medium temperature hydrochloric acid. Therefore, in the past thirty years, it has been widely used in harsh corrosive environments such as chemical, petrochemical, flue gas desulfurization, pulp and paper, environmental protection and other industrial fields.

HashiThe various corrosion data of C-276 alloy have their typicality, but they cannot be used as specifications, especially in unknown environments, and must be tested before material selection. There is not enough Cr in Hastelloy C-276 alloy to resist corrosion in highly oxidizing environments, such as hot concentrated nitric acid. The production of this alloy is mainly aimed at the chemical process environment, especially in the presence of mixed acids, such as the discharge pipe of flue gas desulfurization systems. The following table shows the comparative corrosion test results of four alloys in different environments. (All welding samples are welded using self melting tungsten inert gas arc welding)

l Comparative Corrosion Test of Four Metals in Different Environments

l HashiC-276 alloy can be used as a flue gas desulfurization component in coal-fired systems, and in this environment, C-276 is the most corrosion-resistant material. The following table shows the corrosion comparison test results of C-276 alloy and typical 316 in the "green death" solution of the flue gas simulation system.

l Corrosion Comparison Test in "Green Death" Solution

l As shown in the table above,C-276 alloy has excellent corrosion resistance to mixed acid and salt solutions containing chloride ions.

HashiThe addition of Cr, Mo, and W in C-276 alloy greatly improves its resistance to pitting and crevice corrosion. C-276 alloy is considered inert in seawater environments, so it is widely used in marine, saltwater, and high chlorine environments, even in strong acid and low pH conditions. The following table compares the occurrence of crevice corrosion of four metals in a 6% FeCl3 solution (executed according to ASTM standard G-48).

l Occurrence of crevice corrosion

l The high content of Ni and Mo in C-276 alloy makes it highly resistant to chloride ion stress corrosion cracking. The following table shows the stress corrosion cracking test results of four metals in different chloride ion solutions.

l Chloride ion stress corrosion cracking test results

3、 Welding and heat treatment

The welding performance of C-276 alloy is similar to that of ordinary austenitic stainless steel. Before using a welding method to weld C-276, measures must be taken to minimize the decrease in corrosion resistance of the weld and heat affected zone, such as gas tungsten arc welding (GTAW), gas metal arc welding (GMAW), submerged arc welding, or other welding methods that can minimize the decrease in corrosion resistance of the weld and heat affected zone. However, welding methods such as oxyacetylene welding that may increase the carbon or silicon content in the material weld and heat affected zone are not suitable for use.

Regarding the selection of welding joint forms, you can refer toThe successful experience of ASME Boiler and Pressure Vessel Code for C-276 welded joints.

It is best to use mechanical processing for welding grooves, but mechanical processing can cause work hardening, so it is necessary to polish the groove before welding.

Suitable heat input speed should be used during welding to prevent the occurrence of thermal cracks.

In the vast majority of corrosive environments,C-276 can be applied in the form of welded components. But in extremely harsh environments, C-276 materials and welded parts need to undergo solution heat treatment to obtain the best corrosion resistance.

The welding of C-276 alloy can choose to use itself as welding material or filler metal. If it is required to add certain components to the weld seam of C-276, such as other nickel based alloys or stainless steel, and these welds will be exposed to corrosive environments, then the welding rod or wire used for welding must have corrosion resistance equivalent to that of the base metal.

HashiThe solid solution heat treatment of C-276 alloy material includes two processes: (1) heating at 1040 ℃~1150 ℃; (2) Quickly cool to a black state (around 400 ℃) within two minutes, and the treated material has excellent corrosion resistance. Therefore, only stress relieving heat treatment of Hastelloy C-276 alloy is ineffective. Before heat treatment, it is necessary to clean the surface of the alloy of any dirt, such as oil stains, that may produce carbon elements during the heat treatment process.

During welding or heat treatment, oxides are generated on the surface of C-276 alloy, which reduces the Cr content in the alloy and affects its corrosion resistance. Therefore, surface cleaning is necessary. Stainless steel wire brushes or grinding wheels can be used, followed by immersion in a mixture of nitric acid and hydrofluoric acid in an appropriate ratio for acid washing,butRinse thoroughly with clean water afterwards.