CUSTOMIZED TUBESHEET SA266 GR.2 CS FORGED TYPE FOR HEAT EXCHANGER
Overview
The tubesheet is a round steel plate drilled with holes slightly larger than the outer diameter of the pipe, which serves as a fixing and sealing medium for the pipe in a heat exchanger. A fitting that penetrates and welds a pipe to secure it. The accuracy of tube plate processing, especially the spacing and diameter tolerance of tube holes, verticality, and smoothness, greatly affect the assembly and performance of the chemical equipment listed above.
ASTM A266/ A266M is the standard specification for carbon steel forgings for pressure vessel components. It covers four grades of carbon steel forgings for boilers, pressure vessels, and associated equipment: Grade 1 & Grade 2 & Grade 3 & Grade 4. The UNS number designation for each grade is K03506 [Grade 1], K03506 [Grade 2], K05001 [Grade 3], and K03017 [Grade 4], respectively. The most commonly used forgings manufactured in accordance with ASTM A266 include tube sheets, hubbed flat heads, or nozzles, that are ordered for ASME Boiler and Pressure Vessel Code applications.
The steel shall be made by a melting process and shall be subsequently forged as closed as practical to the specified shape and size of finished products. Surfaces of ASTM A266 forgings shall be machined as designated by the purchaser. Unmachined surfaces shall be sufficiently free of scale to permit inspection. Machining are generally performed after heat treatment. Welding repair is not permitted to ensure good quality.
Tubesheets are widely used in industries such as tubular heat exchangers, boilers, pressure vessels, steam turbines, and large central air conditioning. Mainly used in chemical vessels, such as tubular heat exchangers, pressure vessels, boilers, condensers, central air conditioners, evaporators, and seawater desalination, to support and fix the tubes. The metal material not only has strong rigidity, but also has great heat conduction performance.
Chemical Composition
| Item | Chemical Req. for ASTM A266, % |
| Gr. 1 & 2 | Gr. 3 | Gr. 4 |
| C | ≤ 0.30 | ≤ 0.35 | ≤ 0.30 |
| Mn | 0.40~1.05 | 0.80~1.35 | 0.80~1.35 |
| P | ≤ 0.025 | ≤ 0.025 | ≤ 0.025 |
| S | ≤ 0.025 | ≤ 0.025 | ≤ 0.025 |
| Si | 0.15~0.35 | 0.15~0.35 | 0.15~0.35 |
Mechanical Properties
Tensile
Requirements | Gr. 1 | Gr. 2 & 4 | Gr. 3 |
T.S min.
ksi [Mpa] | 60~85
[415~585] | 70~95
[485~655] | 75~100
[515~690] |
Y.S min.
ksi [Mpa] | 30
[205] | 36
[250] | 37.5
[260] |
EL. in 2" or
[62.5 mm]
min. % | 23
[21] | 20
[18] | 19
[17] |
R.o.A
min. % | 38 | 33 | 30 |
ASTM A266
Grade | Brinell Hardness
HBW |
| 1 | 121~170 |
| 2 | 137~197 |
| 3 | 156~207 |
| 4 | 137~197 |
Heat Treatment
After forging and before reheating for heat treatment, the forgings in accordance with ASTM A266 shall be cooled in such a manner as to prevent injury and to accomplish transformation. All the ASTM A266 forgings shall be heat treated by one of the four processes: annealing, normalizing, normalizing and tempering, or liquid quenching and tempering. When tempering is performed, it shall be at a subcritical temperature, but no less than 1100°F [595°C].
Application:
- Tubular heat exchanger
- pressure vessels
- boilers
- condensers
- central air conditioners
- evaporators
- seawater desalination
Product Tags:
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Customized Tubesheet SA266 GR.2 CS Forged Type For Heat Exchanger Images
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