ADNOC-Certified Stainless Steel 431 Fastener Manufacturer Ex-Stock M3–M120, MTC EN 10204 3.1 & 3.2 Forging & CNC Machining In-House Since 2012

Stainless Steel 431 Fasteners

Stainless Steel 431 Fasteners Characteristics

Sizes In StockM3 to M120, Metric Coarse Series
Delivery TimeEx-Stock: 2–5 Days • Mill-Order: 3–4 Wks
Grade / UNSUNS S43100 / WNR 1.4057
Governing StandardASTM A276, F593, F594
ConditionAnnealed (A) & Hardened-Tempered (T)
Alloying Elements15–17% Cr, 1.25–2.50% Ni
FormsBolt, Nut, Washer, Stud, Screw, Pin
MTC CertificateEN 10204 3.1 and 3.2
Thread SeriesMetric Coarse, ISO 965
HS Code7318
Condition T Hardened
850–1000 MPa Class
Heat-treated to full martensitic strength on request
M3 to M120
Full Metric Range
Bolts, nuts, washers & studs held ready to ship
In-House Forging
Since 2012
Own forge & CNC shop, not a trading counter
ADNOC Certified
Approved Manufacturer
Vendor-approved quality system, audited on record
Direct Exporter
No Trading Layers
Mill-direct documentation, cleared for 19+ countries
Custom Machining
Drive & Thread On Request
Non-standard heads, pitches & lengths cut to drawing
stainless steel 431 fasteners

 

0 · at glance

Mortec At A Glance

Established

Since 2012 • 15+ yrs experience

Manufacturing Units

2 in-house units • Taloja & Mazgaon

Stockyard Area

8,850+ sq.ft • Ready-stock inventory

Certifications

ISO 9001:2015, ADNOC • GST, IEC & MSME

Clientele

100+ clients • India & export markets

Export Reach

19+ countries • GCC, Africa & APAC

Testing Offered

Mechanical, chemical & PMI • MTC EN 10204 3.1 & 3.2

Shipment Documents

Invoice, Packing List • COO, COI, MTC, BL & Lab Report

High Precision SS 431 Nut and Bolts Manufacturer in India, Available Stocks from M3 to M120 Metric Sizes

When your project calls for a fastener that holds torque and resists corrosion better than a plain carbon-steel bolt, Grade 431 earns its place on the drawing. Buyers across South Africa, the UAE, Kenya and Canada come to us because our ex-stock inventory across M3 to M120 metric sizes means an order confirmed today ships within days, not weeks.

Every Stainless Steel 431 fastener leaves our Mumbai facility with full mill test certification and export packing built for long-haul freight. As a direct manufacturer, not a trading desk, we quote from the forge - better pricing, faster answers, and a technical team that checks your drive type, condition and thread pitch before you commit.

01 · Specification

Stainless Steel 431 Fasteners Specification

Direct global exports with MTC from a Stainless Steel 431 Fasteners manufacturer in India.

stainless steel 431 fasteners specification  

SS 431 Fastener Head & Drive Styles

  • Hex, socket, slotted, wing, countersunk
  • Custom head to drawing on request

UNS S43100 Fine & Special Threads

  • ISO 965 metric fine pitch
  • UNC, UNF, BSW on request

WNR 1.4057 Surface Finish & Passivation

  • Passivated per ASTM A967
  • Bright, dull or as-forged finish

Alloy 431 Fastener Testing Methods

  • PMI, tensile, hardness
  • Third-party inspection on request

Grade 431 Supporting Hardware

  • Matching SS 431 washers & spring washers
  • Locknuts and split pins to order

431 Stainless Fastener Manufacturing Origin

  • Indian & European mills
  • Origin certificate on request

Stainless Steel 431 Fasteners Manufacturer In Mumbai Since 2012

Send size, drive and condition - our in-house forging and CNC shop quotes ex-stock and mill-order lead times within hours.

Request Quote Now
02 · Size Range

SS 431 Fasteners Size Chart

Popular Sizes M6 M8 M10 M12 M16 M20
Metric Coarse Thread Pitch - ISO 261 (mm)
Nominal SizeCoarse Pitch (mm)Nominal SizeCoarse Pitch (mm)
M30.50M303.50
M40.70M364.00
M50.80M424.50
M61.00M485.00
M81.25M565.50
M101.50M646.00
M121.75M726.00
M162.00M806.00
M202.50M906.00
M243.00M1006.00

What Changes The Size On Order

Thread SeriesCoarse is default; fine pitch on request
LengthCut to drawing, any length within M120 range
Head/DriveChanges across-flats and head height, not thread
ConditionAnnealed vs hardened blanks machine differently

Need An Exact Dimension Drawing?

Share your size, drive type, length and quantity and we’ll return a dimensioned drawing alongside your quotation - useful for fitment checks before you order.

Request Size Chart

Suppliers of UNS S43100 Wing Screws and Washer for High Stress Applications at Best Price

03 · Product Range

SS 431 Fastener Types

Leading Stainless Steel 431 fasteners supplier in India with ex-stock drive and thread inventory.

Stainless Steel 431 Hex Bolt

Stainless Steel 431 Hex Bolt

ASTM F593 Type 431 • M3–M120
  • Cold-worked or hardened & tempered
  • Best for high-torque structural joints
UNS S43100 Hex Nut

UNS S43100 Hex Nut

ASTM F594 Group 6 • M3–M120
  • Matched proof load to Condition H/HT bolts
  • Available heavy hex on request
SS 431 Flat Washer

SS 431 Flat & Spring Washer

DIN 125 / DIN 127 • Custom OD
  • Load spread & vibration resistance
  • Matched thickness to bolt size
WNR 1.4057 Threaded Rod

WNR 1.4057 Threaded Rod / Stud Bolt

ASTM F593 • Custom Length
  • Full or partial thread, cut to length
  • Used with double-ended tap fittings
SS 431 Wing Screw

SS 431 Wing Screw

Tool-Free • M3–M12
  • Hand-tightened access panels
  • Frequent-adjustment hardware
AISI 431 Socket Head Cap Screw

AISI 431 Socket Head Cap Screw

DIN 912 • M3–M64
  • Compact head for tight bolt patterns
  • High clamp load in a small footprint
DIN 1.4057 Dowel Pin

DIN 1.4057 Dowel Pin

DIN 6325 • Ground & Hardened
  • Precision alignment of mating parts
  • Tight h6/h7 tolerance available
INOX 431 Grub Screw

INOX 431 Grub / Set Screw

DIN 916 • M3–M36
  • Locks collars, pulleys & couplings
  • Cup, cone or flat point options
04 · Industries

Ferritic Stainless 431 Bolts Applications

Industries prefer us as their SS 431 fastener supplier in India for reliable dispatch.

Marine Hardware & Shafts
Pumps & Valves
Aerospace Fasteners
Oil & Gas Equipment
Laboratory Equipment
Food & Beverage Processing
Automotive Components
General Engineering
05 · Codes We Follow

SS 431 Nut Governing Manufacturing Standards

Every SS 431 fastener we produce is checked against these governing specifications before dispatch.

ASTM A276
ASTM A314
ASTM F593 Type 431
ASTM F594 Group 6
DIN EN 10088-3
BS 970 Part 1
JIS G4303
Client-Specific
06 · Composition

UNS S43100 Screws Chemical Composition

ASTM A276 Grade 431's chromium-nickel composition yields heat-treatable strength and superior martensitic corrosion resistance.

Chemical Composition - UNS S43100 (% by weight)
Cr15.00–17.00Chromium
Ni1.25–2.50Nickel
C0.20 maxCarbon
Mn1.00 maxManganese
Si1.00 maxSilicon
P0.040 maxPhosphorus
S0.030 maxSulfur
FeBalanceIron
07 · Strength Data

WNR 1.4057 Threaded Rod Mechanical Properties

Values reflect hardened Condition T fasteners; ASTM A276 Condition A only specifies hardness.

Tensile Strength (Condition T)850–1000 MPa
0.2% Proof Stress (Condition T)665 MPa min
Elongation (Condition T)12% min in 50mm
Hardness (Condition T)248–302 HB
08 · Cross-Reference

SS 431 Fasteners Material Equivalent Grades

Grade 431/UNS S43100 carries equivalent designations across major standards sharing identical base martensitic chemistry.

USAASTM / AISI (USA)

  • UNS S43100
  • ASTM A276 (Bar)
  • ASTM F593 Type 431 (Bolts)
  • ASTM F594 Group 6 (Nuts)

GermanyDIN / EN (Germany)

  • Werkstoff 1.4057
  • EN X17CrNi16-2
  • DIN EN 10088-3

JapanJIS (Japan)

  • SUS431
  • JIS G4303 (Bar)

UKBS (United Kingdom)

  • BS 970 Part 1, 431S29
  • Follows EN 10088-3 (1.4057)

FranceAFNOR (France)

  • NF A35-573, Z15CN16-02
  • X17CrNi16-2 equivalent

SwedenSS (Sweden)

  • SS 2321

Building To A Specific DIN, JIS Or BS Reference?

Tell us your callout and we cross-match the equivalent 431 designation before we quote.

Confirm My Standard
09 · Buyer Question

EN 1.4057 Washer Magnetic Properties & Corrosion Behaviour

Two questions our South African, UAE and Canadian buyers ask before every order - answered at a glance.

Magnetic: Yes
Salt Water: Good
Tropical Water: Fair
Vs Grade 304: Similar
Scaling Limit: 870°C
Best Finish: Hardened, Smooth

Grade 431 is a martensitic stainless and remains magnetic in both annealed and hardened conditions.

10 · Comparison

SS 431 vs SS 316 vs SS 410 Fasteners

As a direct manufacturer, we help you navigate the top three fastener grade trade-offs.

SS 410 (S41000)

  • Family: Martensitic, lower Cr
  • Hardened Tensile: Lower than 431
  • Magnetic: Yes
  • Best For: General-purpose bolting
  • Relative Cost: Lower

SS 431 (S43100)

  • Family: Martensitic, Ni-bearing
  • Hardened Tensile: 850–1000 MPa
  • Magnetic: Yes
  • Best For: High-stress shafts, marine bolting
  • Relative Cost: Medium

SS 316 (S31600)

  • Family: Austenitic, Cr-Ni-Mo
  • Hardened Tensile: Not heat-treatable
  • Magnetic: No (typically)
  • Best For: Chemical, marine wetted parts
  • Relative Cost: Higher

UNS S43100 Fastener Exporter In India To Durban, South Africa

Container-ready 431 bolt, nut and washer pricing for Durban and Cape Town-bound shipments within days.

Request Export Quote
11 · Fabrication

DIN 1.4057 Dowel Pin Heat Treatment & Hardening Process

Overcoming hardening challenges with strict process control as a Stainless Steel 431 Fasteners Exporter.

1

Process Anneal

Heat to 620–660°C, then air-cool to soften for machining.

2

Hardening

Austenitise at 980–1065°C, hold ~30 min, oil or air quench.

3

Tempering

Temper to target strength; avoid the 425–600°C toughness dip.

4

Finish & Inspect

Grind, passivate, then hardness and dimensional check.

12 · Finish & Packing

ASTM A193 Grade 431 Hex Bolt Passivation, Finish & Export Packing

The surface leaving our facility is built to survive the voyage as well as the application.

ASTM A967 Passivation
Bright Finish
Dull / As-Forged Finish
VCI Anti-Rust Wrap
Bin & Carton Packing
Export Wooden Crating
Global Reach

Where Our Stainless Steel 431 Fasteners Ship

Ex-stock and mill-order dispatch to buyers across the Gulf, Africa, the Americas and Asia-Pacific, alongside strong domestic demand from Mumbai, Ahmedabad, Bengaluru, Chennai and Pune.

Key Export Markets
UAEUAE
Saudi ArabiaSaudi Arabia
TurkeyTurkey
CanadaCanada
UKUnited Kingdom
SingaporeSingapore
USAUnited States
MexicoMexico
ThailandThailand
ItalyItaly
NetherlandsNetherlands
GermanyGermany
PhilippinesPhilippines
MalaysiaMalaysia
UgandaUganda
IndonesiaIndonesia
South AfricaSouth Africa
VietnamVietnam
VenezuelaVenezuela

ASTM F593 Type 431 Bolt Supplier In Ahmedabad - ADNOC Approved

Ahmedabad and Gujarat-belt buyers get the same ADNOC-approved 431 stock as our export accounts.

Get Supplier Quote
13 · Turnaround

INOX 431 Hex Nut Delivery Timeline By Shipping Mode

Confirmed SS 431 fastener orders ship from Mumbai same-week; chosen freight determines delivery.

Ex-Stock Dispatch

Confirmed metric-size orders leave our facility in 2–5 working days

Sea Freight

The lowest-cost route, typically 1–4 weeks depending on destination port

Air Freight

3–7 days for shutdown-critical or spare-part top-up orders

Country-Specific ETA

Share your destination port or city for a firm delivery date

14 · Quality

AISI 431 Socket Head Cap Screw Testing & Certification

All requested checks are recorded on your mill test certificate prior to dispatch.

PMI Testing
Tensile & Proof Load Test
Hardness Test
Dimensional Check
MTC 3.1
Chemical Analysis
Third-Party Inspection
Heat Number Traceability
15 · FAQs

Stainless Steel 431 Fasteners FAQs

Quick buyer FAQs from a direct, in-house Stainless Steel 431 fastener manufacturer.

What is 431 stainless steel used for?

Used for nuts and bolts - includes SS 431 Nut and INOX 431 Hex Nut.

What is the difference between SS 316 and SS 431 fasteners?

316 resists corrosion better; 431 is stronger, like our AISI 431 Socket Head Cap Screw.

Is stainless steel 431 magnetic?

Yes, always magnetic - true UNS S43100 Screws differ from ferritic stainless 431 bolts.

Can you weld 431 stainless steel fasteners?

Preheat first - applies to WNR 1.4057 Threaded Rod or EN 1.4057 Washer.

What sizes of Stainless Steel 431 fasteners do you supply?

We stock M3–M120, including DIN 1.4057 Dowel Pin and ASTM A193 Grade 431 Hex Bolt.

Stainless Steel 431 Fasteners - Built On Trust With Mortec
Condition T hardening delivers 850–1000 MPa fastener strength
Ex-stock M3–M120 across bolts, nuts, washers & studs
Every SS 431 fastener batch MTC tested to EN 10204 3.1
Custom thread length, passivation & export crating worldwide

Materials



Products

Certifications & Credentials
Certified to PED 2014/68/EU for the manufacture of forged steel products
Stock, distribute and trade Steel Flanges, Nuts and Bolts, and precision-machined parts in Nickel Alloys, High Temperature Alloys and Super Alloys
Since 2012, exporting Oil and Gas piping items built to NACE MR0175 / ISO 15156 across the Egypt, Tunisia, Netherlands, Azerbaijan, South Africa, Algeria, Saudi Arabia and Morocco
Hold the largest import and stock inventory of bolting accessories, in both ferrous and non-ferrous metals, in India

Authorized Supplier For The Following Companies - Material At Reseller Price For Traders

Associated Companies - ADNOC, SABIC, Saudi Aramco, GASCO, ORPIC, KNPC, QATARGAS

Get A Quick Quote