ASTM A335 P9 Alloy Steel Studded Fin Tube For HVAC Systems

1. What is ASTM A335 P9 Studded Fin Tube?

ASTM A335 P9 Studded Fin Tube is a high-temperature solution engineered for severe sulfidation and ash erosion environments. It combines a seamless chromium-molybdenum alloy steel base tube (ASTM A335 P9, UNS S50400) with carbon steel stud-type fins resistance-welded perpendicularly to the surface. This robust design maximizes heat transfer area while preventing ash buildup, delivering 5x longer sulfidation resistance than carbon steel in refinery heaters, coker units, and waste incinerators operating up to 600°C (1,112°F).

2. Chemical & Mechanical Properties

Dimensional Specifications:

Chemical Composition (%)

Mechanical Properties

3. Key Applications & Competitive Advantages

● Refinery Heaters: Convection sections in crude/vacuum distillation units (NACE RP0472 compliant).

● Delayed Cokers: Transfer line exchangers for 500°C+ vapors.

● Waste-to-Energy: Boiler tubes for municipal solid waste (MSW) incinerators.

● Coal-Fired Plants: Economizers handling >50g/Nm³ fly ash.

● Chemical Processing: Sulfuric acid regeneration heaters.

4.Why choose ASTM A335 Gr.9 Studded Fin Tube:

A:Company Competitiveness:

Yuhong Holding Group has more than 35 years experience for steel pipe and tube , fin tube , main application for Petrochemical , Oil refinary, Furnace, heating, boiler, heat exchanger, air cooler,.., till now YUHONG brand products already exported more than 85 countries, which like UK, ITALY, SPAIN , USA, MEXICO , COLOMBIA , BRAZIL, SAUDI ARANBIA , OMAN, QATAR, U.A.E, KOREA, ...., YUHONG brand already won good reputation in the market.

B:Product Competitiveness:

● Ash Self-Cleaning: Stud spacing reduces fouling by 60% vs. helical fins (EPRI Study).
● 10-Year Lifespan: Withstands cyclic operation per API 530.
● Cost Saving: 35% lower OPEX than refractory-lined carbon steel.
● Rapid Delivery: 50+ standard sizes (OD 25–152mm) in stock.

Yuhong Holding Group has more than 35 years experience for pipeline products, till now we have 3 big joint venture factories,  the total production area more than 130000 square meters, and more than 600 workers with 106 production lines give our clients excellent supporting always.   The factories already got certificates like : ABS, LR, DNV-GL, BV, KR, CCS, ASME, ISO 9001, ISO14001, ISO18001, ect.

Our factories main products as below : 
Factory 1th: Stainless steel seamless tube, Duplex steel seamless tube, Super duplex steel seamless tube, Nickel alloy steel seamless tube;

Factory 2th: Carbon steel seamless tube, Alloy steel seamless tube; Enhanced Heat Tranfer Tube, low fin tube ,U bending workshop;
Factory 3th: High frequency welding fin tube(HFW fin tube, Solid Fin tube, Studded Tube, Serrated Fin tube, Longitudinal welding fin tube), Wound fin tube(L type fin tube, LL type fin tube,  KL type fin tube), Embedded G type fin tube , Extruded fin tube,  low fin tube, U bend & 180deg. Return;

Yuhong Holding Group also has gained rich experience for project package( products contain:Pipes, Fittings, Flanges, heat exchanger, furnace, fired heater, air cooler, boiler) , YUHONG brand has marked its global presence in more than 85 countries, like, Korea, USA, Canada, Mexico, Colombia, Bolivia, Chile, Argentina, Brazil, Ecuador, Austria, New Zealand, Singapore, Malasyia, Indonesia, Thailand, Vietnam, Ukraine, Turkey,Sauid Arabia, Qatar, U.A.E,Israel,India, UK, France, Italy, Gernmany, Poland, Spain,... We have successfully implemented the orders of Cross Country Pipelines for our valuable customers. In addition, we have also developed a huge network of contacts and strategic alliances with most important manufacturers as stockists around the world.