316H Stainless Steel Pipes & Tubes

 

Type 316H is a higher carbon variant of 316 making the steel more suitable for use in applications where elevated temperatures are present. Stabilized Grade 316Ti offers similar qualities. 

The increased carbon content delivers a greater tensile and yield strength. The austenitic structure of the material also gives this grade excellent toughness, even down to cryogenic temperatures.

The steel lends itself well for use in the petrochemical, gas and chemical industry. Prosaic Steel supply Grade 316H to a variety of customers including fabricators of pressure vessels, industrial boilers and heat exchangers. 


 Benefits of using Type 316H Stainless Steel

  •  Increased carbon content heat resistant qualities
  •  Greater tensile yield strength
  •  Greater short and long term creep strength

     Product Range 
     Specifications: ASTM A/ASME SA213/A249/A269/A312/A358 CL. I to V ASTM A789/A790
     Sizes (Seamless): 1/2" NB - 24" NB
     Sizes (ERW): 1/2" NB - 24" NB
     Sizes (EFW): 6" NB - 36" NB  

     Wall Thickness available:
     Schedule 5S - Schedule XXS (heavier on request)

     Other Materials Testing:

        NACE MR0175, H2 SERVICE, OXYGEN SERVICE, CRYO SERVICE, etc.

     Dimensions:

        All Pipes is manufactured and inspected/tested to the relevant standards including ASTM, ASME and API etc.

       Background of 316H Stainless Steel Pipes & Tubes

    Grade 316 is the standard molybdenum-bearing grade, second in importance to 304 amongst the austenitic stainless steels. The molybdenum gives 316 better overall corrosion resistant properties than Grade 304, particularly higher resistance to pitting and crevice corrosion in chloride environments. It has excellent forming and welding characteristics. It is readily brake or roll formed into a variety of parts for applications in the industrial, architectural, and transportation fields. Grade 316 also has outstanding welding characteristics. Post-weld annealing is not required when welding thin sections.

    Grade 316L, the low carbon version of 316 and is immune from sensitisation (grain boundary carbide precipitation). Thus it is extensively used in heavy gauge welded components (over about 6mm). Grade 316H, with its higher carbon content has application at elevated temperatures, as does stabilised grade 316Ti.

    The austenitic structure also gives these grades excellent toughness, even down to cryogenic temperatures.



     Composition of 316H Stainless Steel Pipes & Tubes

       Table 1. Composition ranges for 316 grade of stainless steels.


    Grade C Mn Si P S Cr Mo Ni N
    316 Min - - - 0 - 16.0 2.00 10.0 -
    Max 0.08 2.0 0.75 0.045 0.03 18.0 3.00 14.0 0.10
    316L Min - - - - - 16.0 2.00 10.0 -
    Max 0.03 2.0 0.75 0.045 0.03 18.0 3.00 14.0 0.10
    316H Min 0.04 0.04 0 - - 16.0 2.00 10.0 -
    max 0.10 0.10 0.75 0.045 0.03 18.0 3.00 14.0 -


     Mechanical Properties of 316H Stainless Steel Pipes & Tubes

        Table 2.     Mechanical properties of 316 grade stainless steels.

    Grade Tensile Str
    (MPa) min    		 Yield Str
    0.2% Proof
    (MPa) min    		 Elong
    (% in 50mm) min    		 Hardness
    Rockwell B (HR B) max Brinell (HB) max
    316 515 205 40 95 217
    316L 485 170 40 95 217
    316H 515 205 40 95 217


        Note: 316H also has a requirement for a grain size of ASTM no. 7 or coarser.

     Physical Properties of 316H Stainless Steel Pipes & Tubes

        Table 3.     Typical physical properties for 316 grade stainless steels.

    Grade Density
    (kg/m3)    		 Elastic Modulus
    (GPa)    		 Mean Co-eff of Thermal Expansion (m/m/℃) Thermal Conductivity
    (W/m.K)    		 Specific Heat 0-100℃
    (J/kg.K)    		 Elec Resistivity
    (nΩ.m)
    0-100℃ 0-315℃ 0-538℃ At 100℃ At 500℃
    316/L/H 8000 193 15.9 16.2 17.5 16.3 21.5 500 740


     Grade Specification Comparison of 316H Stainless Steel Pipes & Tubes

       Table 4. Grade specifications for 316 grade stainless steels. 

    Grade UNS
    No    		 Old British Euronorm Swedish
    SS    		 Japanese
    JIS
    BS En No Name
    316 S31600 316S31 58H, 58J 1.4401 X5CrNiMo17-12-2 2347 SUS 316
    316L S31603 316S11 - 1.4404 X2CrNiMo17-12-2 2348 SUS 316L
    316H S31609 316S51 - - - - -


    Note: These comparisons are approximate only. The list is intended as a comparison of functionally similar materials not as a schedule of contractual equivalents. If exact equivalents are needed original specifications must be consulted.

    Excellent in a range of atmospheric environments and many corrosive media - generally more resistant than 304. Subject to pitting and crevice corrosion in warm chloride environments, and to stress corrosion cracking above about 60℃. Considered resistant to potable water with up to about 1000mg/L chlorides at ambient temperatures, reducing to about 500mg/L at 60℃.

    316 is usually regarded as the standard “marine grade stainless steel", but it is not resistant to warm sea water. In many marine environments 316 does exhibit surface corrosion, usually visible as brown staining. This is particularly associated with crevices and rough surface finish.

     Heat Treatment of 316H Stainless Steel Pipes & Tubes
    Solution Treatment (Annealing) - Heat to 1010-1120℃ and cool rapidly. These grades cannot be hardened by thermal treatment.