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SS 904L Screws Manufacturer & Exporter in India

Explore SS 904L Screws Manufacturer & Exporter in India manufactured for demanding industrial applications with reliable strength, corrosion resistance and compliance with international standards.
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-196

Min Temp

870

Max Temp

🌡

870

Suitable for continuous service up to approximately 870°C under typical operating conditions.

⚡

620

Typical tensile strength around 620 MPa depending on product form and heat treatment.

🛡

Very Good

Very Good corrosion resistance in a wide range of industrial environments.

⚖

8

Typical density is approximately 8.0 g/cm³.

Product Overview

What are SS 904L Screws?

SS 904L screws are high-alloy austenitic stainless steel fasteners manufactured from UNS N08904 bar stock, conforming to ASTM A193/A276. The alloy’s elevated chromium (19-23%), nickel (23-28%), and molybdenum (4-5%) content, along with copper (1-2%), delivers exceptional resistance to sulphuric acid, chloride pitting, and crevice corrosion. SS 904L screws are non-magnetic, maintain high ductility, and are suitable for use in highly aggressive chemical environments where standard 316L or 317L fasteners fail.

These screws are widely specified for process equipment in the chemical, petrochemical, and offshore industries, especially where resistance to reducing acids and chloride stress corrosion cracking is critical. SS 904L screws are supplied with EN 10204 3.1 certification and full traceability for demanding applications.

Quick Specifications

MaterialStainless Steel 904L
UNS NumberN08904
DIN Number1.4539
Material StandardASTM A276 / ASTM A193
Screw Standard (Metric)DIN 912 / DIN 7991 / ISO 4762
Screw Standard (Inch)ASME B18.3
Thread FormISO Metric / UNC / UNF
Diameter RangeM3-M64 / ?"-2½"
Tensile Strength490 MPa (71 ksi) min
Yield Strength220 MPa (32 ksi) min
HardnessMax 90 HRB / 220 HB
? All material certified by NABL-accredited laboratory. PMI and IGC test available on request.

Complete the Fastener Set

Other SS 904L Fastener Products Available from RealBolt

RealBolt also manufactures the complete SS 904L fastener range from certified stainless steel bar stock, including SS 904L Bolts, SS 904L Nuts, SS 904L Washers, SS 904L Studs, and SS 904L Threaded Rods. All SS 904L fastener types are produced to ASTM with full EN 10204 MTC 3.1/3.2 documentation.
SS 904L Bolts
SS 904L Nuts
SS 904L Washers
SS 904L Studs
SS 904L Threaded Rods

Technical Data

SS 904L Screws Dimensions, Sizes & Thread Standards

SS 904L Screws are available in metric M6–M100 and inch ¼″–4″ as standard. Per DIN 912 (socket head cap), DIN 7991 (countersunk), ISO 4762. Custom lengths in 5mm increments. Inch dimensions available per ASME B18.3. All SS 904L screws dimensions are verified against applicable DIN, ISO, and ASME B18 standards

Socket Head Cap Screw Dimensions - Metric (DIN 912 / ISO 4762)

Size (M)Pitch (mm)Head Dia (mm)Head Ht (mm)Hex Socket (mm)Min L (mm)Max L (mm)
M30.55.53.02.5650
M40.77.04.03.0860
M50.88.55.04.01070
M61.010.06.05.01280
M81.2513.08.06.016100
M101.516.010.08.020120
M121.7518.012.010.025150
M162.024.016.014.030200
M202.530.020.017.035250
M243.036.024.019.040300
M303.545.030.022.050400
M364.054.036.027.060500
M424.563.042.032.070600
M485.072.048.036.080700
M565.584.056.041.090800
M646.096.064.046.0100900

Dimensional & Material Standards

StandardCoversThread
DIN 912Socket head cap screwsMetric
DIN 7991Countersunk socket screwsMetric
ISO 4762Hexagon socket head screwsMetric
ASME B18.3Socket cap, set & shoulder screwsUNC/UNF
ISO 14581Flat countersunk head screwsMetric
ISO 7380Button head socket screwsMetric
Material StandardRequirement
ASTM A276Bar/rod - UNS N08904
ASTM A193Fastener mechanical
EN 10204 3.1Mill test certificate
EN 10204 3.2TPI-witnessed MTC
ISO 3506-4Stainless fasteners

Material Chemistry

SS 904L Chemical Composition

SS 904L Screws are manufactured from an iron-chromium-nickel alloy with chromium (16–26%), nickel (8–28%), and grade-specific molybdenum additions per ASTM and ASTM A193/A194. Chromium content governs the self-healing passive oxide film; molybdenum (2–6%) enhances chloride pitting resistance; and carbon content determines sensitization risk in welded assemblies.

Chemical Composition per ASTM A276 / A193

ElementComposition (%)
Chromium (Cr)19.0-23.0
Nickel (Ni)23.0-28.0
Molybdenum (Mo)4.0-5.0
Copper (Cu)1.0-2.0
Carbon (C)0.02 max
Silicon (Si)1.0 max
Manganese (Mn)2.0 max
Phosphorus (P)0.045 max
Sulphur (S)0.035 max
Iron (Fe)Balance
? All heats verified by NABL-accredited spectrometry. PMI and IGC test available on request.

Why SS 904L Alloy Composition Matters for Screws

High Nickel & Molybdenum — Acid Resistance
The elevated nickel and molybdenum content in SS 904L screws provides outstanding resistance to reducing acids, especially sulphuric acid, and prevents pitting and crevice corrosion in chloride-rich environments.
Copper Addition — Non-Oxidising Acid Protection
Copper enhances resistance to non-oxidising acids such as sulphuric and phosphoric acid, making SS 904L screws ideal for chemical process equipment and acid storage tanks.
Low Carbon — No Sensitisation
With a maximum carbon content of 0.02%, SS 904L screws are immune to intergranular corrosion after welding, ensuring long-term reliability in welded assemblies and flange joints.

Fastener Performance

SS 904L Screws Mechanical Properties & Torque Reference

The table below lists mechanical properties and torque reference for SS 904L Screws per ASTM. SS 904L screws achieve 620 MPa tensile strength, with hardness, yield, and elongation values verified by NABL-accredited testing and reported in the EN 10204 MTC.

Screw SizeDry (Nm)Lubricated (Nm)Clamp Load (kN)
M61087.5
M8252014
M10504022
M12856832
M1621016863
M2042033698
M24730584141
M3014601168226
?? Anti-galling: Use molybdenum-based or PTFE anti-seize. Lubricated values assume K=0.16. Avoid over-torquing austenitic stainless screws to prevent thread galling.

Industry Applications

SS 904L Screws Applications — Industries & End Uses

SS 904L Screws from RealBolt are specified across food and dairy, pharmaceutical, marine, chemical processing, and oil and gas where very good corrosion resistance and 620 MPa tensile strength are required for reliable fastener performance. Click each industry below for detailed application examples.
SS 904L screws are widely used in sulphuric acid, phosphoric acid, and acetic acid process equipment, including reactor covers, agitator assemblies, and acid storage tanks, where superior resistance to reducing acids is required.
Socket head and countersunk screws for seawater intake screens, brine concentrators, and evaporator vessels, where high chloride resistance and immunity to crevice corrosion are essential.
Fastening of bleaching towers, digesters, and chemical dosing systems exposed to aggressive bleaching agents and acidic liquors, where 316L fasteners are prone to pitting and stress corrosion cracking.
SS 904L screws are specified for splash zone and submerged applications in offshore platforms, riser clamps, and marine heat exchangers, providing long-term resistance to seawater and brine.

SS 904L Screws Standards & International Certifications

SS 904L Screws from RealBolt Engineering Industries are manufactured to internationally recognised fastener dimensional standards covering thread form, tolerances, strength grades, and quality requirements. Every batch ships with EN 10204 MTC 3.1/3.2, IS 12427 compliance, ISO 3506 material certification, NACE MR0175, and PMI (XRF) reports — available on request for all orders.
Standards
DIN 84 DIN 85 DIN 912 DIN 913 DIN 914 DIN 915 DIN 916 DIN 6912 DIN 7984 DIN 7985 DIN 7991 DIN 965 DIN 966 DIN 967 ISO 4762 ISO 10642 ISO 14579 ASME B18.3 ASME B18.6.3 EN ISO 4762 IS 1363 IS 1367 IS 12427 SAE J933
Certifications
ISO 9001:2015PED 2014/68/EUNABL LabEN 10204 3.1 / 3.2

Buy SS 904L Screws from India's Leading Manufacturer — Get a Competitive Quote Today

Partner with RealBolt — India’s leading manufacturer of certified SS 904L Screws — for competitive pricing, EN 10204 MTC 3.1/3.2 documentation, and fast Mumbai dispatch. Standard sizes are ex-stock; custom dimensions accepted with 2–3 week lead time. Request your quote today.
022-6743-7972
+91 90226 36025
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Answers for Buyers

SS 904L Screws — Frequently Asked Questions

Browse expert answers to common questions about SS 904L Screws from RealBolt — covering ASTM A193/A194 grades, chloride resistance, temperature limits, sensitization, sizes, and MTC documentation. Contact our technical team directly for project-specific guidance on SS 904L screws selection and pricing.
SS 904L socket head screws are available to DIN 912 (metric), ISO 4762, DIN 7991 (countersunk), and ASME B18.3 (inch series). Button head and set screws are also supplied per ISO 7380 and DIN 913. Custom thread forms (UNC, UNF, BSW) are available on request with short lead times.
Molybdenum-based or PTFE anti-seize is recommended for SS 904L screws to prevent galling and cold welding. Apply to threads and under the head. Avoid copper-based anti-seize in chloride environments. Reduce torque by 20% when lubricated.
Yes – SS 904L screws offer excellent resistance to pitting, crevice corrosion, and stress corrosion cracking in seawater and brine, outperforming 316L and 317L. They are widely used in desalination, marine, and offshore applications without the need for additional coatings.
No MOQ for standard sizes (M6-M24) in stock – single piece supply available for urgent maintenance. Custom sizes or non-standard threads may require a 10 kg minimum. Bulk discounts apply at 50, 200, and 500 pieces.

Industrial Cities We Serve:

  • Ahmedabad
  • Aurangabad
  • Bengaluru
  • Chennai
  • Coimbatore
  • Faridabad
  • Gandhidham
  • Greater Noida
  • Gurugram
  • Hazira
  • Hosur
  • Hyderabad
  • Jamnagar
  • Jamshedpur
  • Ludhiana
  • Mumbai
  • Mundra
  • Mysuru
  • Nagpur
  • Nashik
  • Navi Mumbai
  • Noida
  • Pune
  • Rajkot
  • Sanand
  • Surat
  • Thane
  • Tiruppur
  • Vadodara
  • Visakhapatnam

Countries We Export To:

  • US
  • Canada
  • Mexico
  • Germany
  • UK
  • France
  • Italy
  • Spain
  • Netherlands
  • Belgium
  • Poland
  • Sweden
  • Norway
  • Denmark
  • Turkey
  • UAE
  • Saudi Arabia
  • Qatar
  • Oman
  • Kuwait
  • Bahrain
  • South Africa
  • Egypt
  • Nigeria
  • Australia
  • New Zealand
  • Singapore
  • Malaysia
  • Indonesia
  • Thailand
  • Vietnam
  • South Korea
  • Japan
  • Brazil