Acid-resistant 316 seamless tube is a premium austenitic stainless steel product specifically designed for service in acidic and chemically aggressive environments. The addition of 2-3% molybdenum distinguishes this grade from standard 304, providing significantly enhanced resistance to a wide range of acids, including sulfuric, phosphoric, acetic, and organic acids, as well as chloride-induced pitting and crevice corrosion.

The seamless manufacturing process ensures uniform wall thickness, consistent mechanical properties, and a complete absence of a longitudinal weld seam. This seamless construction eliminates potential weak points associated with welded seams, making acid-resistant 316 seamless tube the preferred choice for chemical processing plants, pharmaceutical facilities, food processing equipment, and industrial acid handling systems.

The low carbon version (316L) with 0.03% maximum carbon content prevents carbide precipitation during welding, ensuring optimal corrosion resistance in the heat-affected zone without requiring post-weld heat treatment. For most acid service applications, 316L is recommended due to its superior resistance to intergranular corrosion in welded conditions.

The molybdenum content provides excellent resistance to reducing acids, while the chromium content offers protection in oxidizing environments. This dual-protection mechanism makes 316 one of the most versatile acid-resistant stainless steels available, suitable for handling a broad spectrum of corrosive chemicals across a wide temperature range.

The molybdenum content is the critical element for acid resistance.

Acid-resistant 316 seamless tube delivers the following mechanical properties in the solution annealed condition:

High-Temperature Tensile Strength (Typical values for 316L):

The molybdenum content provides superior resistance to a wide range of acids.

316 is suitable for dilute sulfuric acid at moderate temperatures. For concentrated or high-temperature sulfuric acid, higher alloys (904L, Hastelloy) are required.

316 is widely used in phosphoric acid production, fertilizer plants, and food-grade phosphoric acid handling.

316 is the standard material for acetic acid production and handling in the chemical and food industries.

For high-temperature nitric acid service, 304 or 304L is typically preferred over 316.

316 has limited resistance to hydrochloric acid. Higher alloys (Hastelloy C-276, zirconium) are required for HCl service.

Acid-resistant 316 seamless tubes are used across industries where acidic media handling is required.

• Sulfuric acid transfer lines (dilute concentrations)

• Phosphoric acid plant piping

• Acetic acid production and handling systems

• Organic acid processing equipment

• Dye and intermediate chemical transfer lines

• Reactor and heat exchanger tubing

• Acidic formulation transfer lines

• Clean-in-place (CIP) systems using acid rinses

• Fermentation and bioreactor tubing

• Solvent and reagent transfer lines

• Acidic food processing (tomato, citrus, vinegar)

• Beverage handling systems (fruit juices, soft drinks)

• Brewery and winery acid cleaning systems

• Dairy processing (lactic acid exposure)

• Phosphoric acid service

• Ammonium phosphate slurry lines

• Acid recycle and recovery systems

• Pickling acid lines (dilute sulfuric or hydrochloric with inhibitors)

• Acid recovery and regeneration systems

• Electroplating and anodizing acid lines

• Bleach plant acid lines

• Chlorine dioxide generator tubing

• Acid washing systems

The seamless manufacturing process for acid-resistant tubes ensures consistent quality.

1. Step 1 – Billet Piercing

   Solid billets of 316/316L composition are heated and pierced to form a hollow shell.

2. Step 2 – Cold Drawing

   The hollow shell is cold drawn through a die and over a mandrel. Multiple passes with intermediate annealing achieve precise dimensions.

3. Step 3 – Solution Annealing

   The tube is heated to 1010-1120°C (1850-2050°F) and water quenched to dissolve carbides.

4. Step 4 – Pickling

   Acid pickling removes scale and restores corrosion resistance.

5. Step 5 – Straightening and Finishing

   The tube is straightened, cut to length, and ends finished.

For inquiries, technical data sheets, or a quotation for acid-resistant 316 seamless tube (316L seamless tube / molybdenum-bearing austenitic tube) for chemical and corrosive service, please contact our sales team.

We provide:

• Mill test certificates with full traceability

• 316L option for welded acid service

• Competitive pricing for project quantities

• Reliable delivery worldwide

• Technical support for material selection