ASTM A335 P9 Alloy Steel Studded Pipe Fin Tube Heat Exchanger Tube
Studded Pipe also called studded tubes, Nailhead Pipe or stud Pipe. It is one
type of High HFW / Frequency Welded fin tube. Studded pipes are
used as an alternative to finned tubes in heat exchangers mainly in
the petrochemical industry where the surface is exposed to
particular corrosion and aggression by gasses and vapors. This type fin tube can improving heat transfer efficiency much more
than bare tube. Because of their relatively thicker Cross-section
as compared to fins, Studded pipe is one of the mechanically
Strongest extended-surfaces Available.
Base pipe/tube material
Stainless steel: ASME SA213/ASTM A213, ASME SA249/A249 ,ASME SA312/A312: TP304,304L,
TP304H, TP310S, TP310H, TP316L, TP316H, TP316Ti, TP317, TP317L,
TP321,TP321H, TP347, TP347H, TP904L
Duplex/Super Duplex Steel: ASME SA789/A789 , ASME SA790/A790: S31803, S32205, S32750, S31500,
S32304, S32900
Carbon Steel: ASME SA106/ASTM A106 Gr B, Gr C, ASME SA179/ASTM A179, ASME
SA192/ASTM A192, ASTM A214, ASTM A210 Gr.A1
Alloy Steel: ASME SA213/ASTM A213 T1, T11, T12, T22, T23, T5, T9, T91, T92 ;
ASME SA335 /ASTM A335 P1, P11, P12, P22, P23, P5, P9 , P91, P92 ,
16Mo3, 15Mo3, 13CrMo-4, 12Cr1MoVG.
Nickel Alloy Steel Grade:Hestalloy:C-276, C-4, C-22, C-2000, X, B-2, B-3, G-30, G-35.
Monel:400,401, 404, R-405, K500.
Inconel:600, 601, 617, 625, 690, 718, 740, X-750. Incoloy:800,
800H, 800HT, 825, 840.
Pure Nickel:Ni-200, Ni-201, Ni-270. NS Alloy:Ns 1101, NS1102, NS1103,NS3105.
Copper Alloy Steel: ASTM B111(70400, C70600, C71500, C71640,
C68700, C44300)
Fin material: Alloy Steel , Stainless Steel , Carbon Steel .
Stainless steel High Frequency Welded fins tube, carbon steel High
Frequency Welded fins tube, Duplex High Frequency Welded fins tube
Super Duplex High Frequency Welded fins tube, Air cooler fins tube,
Air preheater fins tube. Extruded fins tube, Serrated fin tubes
Specification of studded pipe A335 alloy steel finned pipe
Base pipe O.D: 15.88-219.1mm
Fin height: 6-50mm
Fin thickness: 0.3-3.0mm
Fin pitch: as customer's request.
End: Plain Ends, Beveled Ends
No fin area on both side: As Customer's request and drawing
Alloy Steel Chemical Compositions
| Grade | UNS Designation | Composition, % |
| Carbon | Manganese | Phosphorus, max | Sulfur, max | Silicon | Chromium | Molybdenum |
| P1 | K11522 | 0.10-0.20 | 0.30-0.80 | 0.025 | 0.025 | 0.10-0.50 | -- | 0.44-0.65 |
| P2 | K11547 | 0.10-0.20 | 0.30-0.61 | 0.025 | 0.025 | 0.10-0.30 | 0.50-0.81 | 0.44-0.65 |
| P5 | K41545 | 0.15MAX | 0.30-0.60 | 0.025 | 0.025 | 0.50MAX | 4.00-6.00 | 0.45-0.65 |
| P9 | K90941 | 0.15MAX | 0.30-0.60 | 0.025 | 0.025 | 0.25-1.00 | 1.00-1.50 | 0.44-0.65 |
| P11 | K11597 | 0.05-0.15 | 0.30-0.60 | 0.025 | 0.025 | 0.50-1.00 | 1.00-1.50 | 0.44-0.65 |
| P12 | K11562 | 0.05-0.15 | 0.30-0.61 | 0.025 | 0.025 | 0.5MAX | 0.80-1.25 | 0.44-0.65 |
| P15 | K11578 | 0.05-0.15 | 0..30-0.60 | 0.025 | 0.025 | 1.15-1.65 | -- | 0.44-0.65 |
| P21 | K31545 | 0.05-0.15 | 0.30-0.60 | 0.025 | 0.025 | 0.50MAX | 2.65-3.35 | 0.80-1.06 |
Advantages of Studded Tubes
1. As the pin rib of the studded tubes is a cantilever structure
with a compact structure, the pin rib will vibrate under the impact
of the air flow, making it difficult to accumulate soot.
2. due to the strong turbulent flushing of flue gas, the studded
tubes heat exchange element has high heat transfer efficiency and
strong self ash removal capability.
Application
The mainly applications for studded tubes is the process heat
recovery of the petrochemical industry, in areas of convection
ovens, vacuum generators for chemical processing, specially used in
petroleum applications. Studded pipes high resistance in the harsh
environments, such as sections of Sulfuric Acid atmospheres, makes
it very useful for the industries mentioned.
- Economizer
- Boilers
- Heat exhangers
- Tube Bundles
- Radiators
- Air Coolers
- Air Preheater
