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Hastelloy G35 Screws Manufacturer & Exporter in India

Explore Hastelloy G35 Screws Manufacturer & Exporter in India manufactured for demanding industrial applications with reliable strength, corrosion resistance and compliance with international standards.
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-200

Min Temp

1100

Max Temp

🌡

1100

Suitable for continuous service up to approximately 1100°C under typical operating conditions.

⚡

800

Typical tensile strength around 800 MPa depending on product form and heat treatment.

🛡

Excellent

Excellent corrosion resistance in a wide range of industrial environments.

⚖

8.9

Typical density is approximately 8.9 g/cm³.

Product Overview

What are Hastelloy G35 Screws?

Hastelloy G35 screws are nickel-chromium-molybdenum alloy fasteners manufactured from UNS N06035 bar stock conforming to ASTM B574. The alloy’s high chromium content (33.2-36.2%) combined with molybdenum (7.6-9.0%) and tungsten (0.6-1.4%) delivers exceptional resistance to oxidising acids, mixed acid environments, and wet process phosphoric acid – performance that austenitic stainless steels cannot approach.

With a PREN exceeding 55, Hastelloy G35 screws resist pitting and crevice corrosion in aggressive chloride-bearing process streams. These screws are specified for chemical reactor closures, phosphoric acid plant equipment, flue gas scrubber internals, and heat exchanger channel covers where standard nickel alloys such as Hastelloy C-276 or Inconel 625 are borderline or inadequate.

Quick Specifications

MaterialHastelloy G35
UNS NumberN06035
DIN Number2.4643
Material StandardASTM B574
Screw Standard (Metric)DIN 933 / DIN 912 / ISO 4017
Screw Standard (Inch)ASME B18.2.1 / ASME B18.3
Thread FormISO Metric / UNC / UNF
Diameter RangeM6-M64 / ¼"-2½"
Tensile Strength690 MPa (100 ksi) min
Yield Strength310 MPa (45 ksi) min
HardnessMax 35 HRC / 220 HB
? All material certified by NABL-accredited laboratory. PMI available on request.

Complete the Fastener Set

Other Hastelloy G35 Fastener Products Available from RealBolt

RealBolt also manufactures the complete Hastelloy G35 fastener range from certified nickel-molybdenum-chromium superalloy bar stock, including Hastelloy G35 Bolts, Hastelloy G35 Nuts, Hastelloy G35 Washers, Hastelloy G35 Studs, and Hastelloy G35 Threaded Rods. All Hastelloy G35 fastener types are produced to ASTM with full EN 10204 MTC 3.1/3.2 documentation.
Hastelloy G35 Bolts
Hastelloy G35 Nuts
Hastelloy G35 Washers
Hastelloy G35 Studs
Hastelloy G35 Threaded Rods

Technical Data

Hastelloy G35 Screws Dimensions, Sizes & Thread Standards

Hastelloy G35 Screws are available in metric M6–M100 and inch ¼″–4″ as standard. Per DIN 933 (hex full thread) / DIN 912 (socket cap) / ISO 4017. Custom lengths in 5mm increments. Inch dimensions available per ASME B18.2.1 and ASME B18.3. All Hastelloy G35 screws dimensions conform to applicable DIN, ISO, and ASME B18 standards.

Hex Screw Dimensions - Metric (DIN 933 / ISO 4017)

Size (M)Pitch (mm)A/F (mm)Head Ht (mm)Min L (mm)Max L (mm)
M61.0104.010150
M81.25135.312200
M101.5176.416250
M121.75197.520300
M162.02410.025400
M202.53012.530500
M243.03615.040500
M303.54618.750600
M364.05522.560800
M424.56526.080800
M485.07530.01001000
M565.58535.01201200
M646.09540.01401500

Dimensional & Material Standards

StandardCoversThread
DIN 933Hex screws, full threadMetric
DIN 912Socket cap screwsMetric
ISO 4017Hex head screws, full threadMetric
ISO 4762Socket head cap screwsMetric
ASME B18.2.1Hex cap screwsUNC/UNF
ASME B18.3Socket head cap screwsUNC/UNF
MSS SP-75High-pressure fastenersUNC
Material StandardRequirement
ASTM B574Bar/rod - UNS N06035
ASTM B575Plate/sheet - UNS N06035
ASTM F468Fastener mechanical properties
NACE MR0175Sour service =35 HRC
EN 10204 3.1Mill test certificate
EN 10204 3.2TPI-witnessed MTC

Material Chemistry

Hastelloy G35 Chemical Composition

Hastelloy G35 Screws derive their exceptional acid corrosion resistance from a precisely controlled nickel-molybdenum-chromium composition per ASTM. High molybdenum and tungsten content suppresses pitting and reducing-acid attack; ultra-low carbon (0.01% max) eliminates sensitization risk in welded assemblies. Full elemental composition is certified in the EN 10204 MTC supplied with every Hastelloy G35 screws order from RealBolt.

Chemical Composition per ASTM B574

ElementComposition (%)
Nickel (Ni)Balance (approx. 47% min)
Chromium (Cr)33.2-36.2%
Molybdenum (Mo)7.6-9.0%
Iron (Fe)1.0% max
Tungsten (W)0.6-1.4%
Carbon (C)0.05% max
Manganese (Mn)1.0% max
Silicon (Si)0.7% max
Cobalt (Co)1.0% max
Copper (Cu)0.50% max
? All heats verified by NABL-accredited spectrometry. PMI available on request.

Why Hastelloy G35 Alloy Composition Matters for Screws

Cr (33.2–36.2%) — Oxidising Acid Resistance
The exceptionally high chromium content in Hastelloy G35 forms a robust passive oxide layer that resists attack in concentrated nitric acid, mixed nitric-hydrofluoric acid, and wet process phosphoric acid — environments that rapidly corrode standard nickel alloys. This makes G35 screws the preferred choice for chemical reactor closures and acid plant equipment.
Mo (7.6–9.0%) — Pitting & Crevice Resistance
Molybdenum elevates the PREN above 55, providing strong resistance to pitting and crevice corrosion under screw heads and in threaded joints exposed to chloride-bearing process streams. Combined with the high chromium level, this dual protection mechanism outperforms Hastelloy C-276 in oxidising-plus-chloride mixed environments.
Low Carbon (0.05% max) — Sensitisation Prevention
The controlled low carbon content prevents chromium carbide precipitation at grain boundaries during welding or elevated-temperature service. Hastelloy G35 screws retain full corrosion resistance in the heat-affected zone without requiring post-weld heat treatment, simplifying fabrication of bolted assemblies.

Fastener Performance

Hastelloy G35 Screws Mechanical Properties & Torque Reference

The table below lists mechanical properties and torque reference for Hastelloy G35 Screws per ASTM. Hastelloy G35 screws achieve 800 MPa tensile strength, with hardness, yield, and elongation values verified by NABL-accredited testing and reported in the EN 10204 MTC.

Tightening Torque Reference - Hastelloy G35 Screws

Screw SizeDry (Nm)Lubricated (Nm)Clamp Load (kN)
M10423418
M12725827
M1617514065
M20345276104
M24600480151
M301200960241
M3621001680350
M4233502680482
?? Anti-galling: Use nickel-based anti-seize (Molykote P-37 or Bostik Never-Seez Pure Nickel). Lubricated values assume K=0.15. Never use copper-based anti-seize on nickel alloys - galvanic corrosion risk.

Industry Applications

Hastelloy G35 Screws Applications — Industries & End Uses

Hastelloy G35 Screws from RealBolt are specified across chemical processing, pharmaceutical, oil and gas, and FGD where excellent corrosion resistance and 800 MPa tensile strength are required for reliable fastener performance. Click each industry below for detailed application examples. Select an industry below to see specific Hastelloy G35 screws application details and RealBolt stock availability.
Hastelloy G35 screws are the benchmark fastener for wet process phosphoric acid (WPA) plant equipment including reactor vessel closures, filter press frames, evaporator channel covers, and heat exchanger tube sheet connections. The alloy’s high chromium content provides corrosion rates below 0.1 mm/year in 85% H3PO4 at elevated temperatures where Hastelloy C-276 and 316L stainless steel fail rapidly.
Hex screws and socket cap screws for nitric acid concentrator column flanges, mixed acid (HNO3 + HF) reactor closures, and nitration plant heat exchanger covers. Hastelloy G35 outperforms all standard nickel alloys in strongly oxidising acid service due to its uniquely high chromium level, making it the preferred specification for fertiliser and explosives manufacturing facilities.
Screw fasteners for FGD absorber tower internals, spray header supports, mist eliminator frames, and ductwork flange connections where saturated HCl and H2SO4-bearing gas streams at 50-80°C create severe pitting conditions. Hastelloy G35 screws provide long-term resistance in both the liquid and vapour phases of FGD service without coating or cathodic protection.
Socket head cap screws and hex screws for chlorine dioxide bleaching stage equipment, washer drum covers, and bleach tower distribution plate connections. The combination of high chromium and molybdenum in G35 resists hypochlorite, chlorine dioxide, and elemental chlorine environments that cause rapid stress corrosion cracking in duplex and super-duplex stainless steels.

Hastelloy G35 Screws Standards & International Certifications

Hastelloy G35 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, PMI (XRF), NACE MR0175/ISO 15156, and NABL-accredited lab reports — available on request for all orders.
Standards
DIN 912 DIN 913 DIN 914 DIN 915 DIN 916 DIN 6912 ISO 4762 ISO 10642 ASME B18.3 EN ISO 4762 IS 1367
Certifications
ISO 9001:2015NACE MR0175NABL LabPED 2014/68/EUMTC 3.1 / 3.2

Buy Hastelloy G35 Screws from India's Leading Manufacturer — Get a Competitive Quote Today

Partner with RealBolt — India’s leading manufacturer of certified Hastelloy G35 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.
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Answers for Buyers

Hastelloy G35 Screws — Frequently Asked Questions

Browse expert answers to common questions about Hastelloy G35 Screws from RealBolt — covering acid corrosion resistance, NACE MR0175 compliance, ASTM standards, available sizes, and MTC documentation. Contact our technical team directly for project-specific guidance on Hastelloy G35 screws selection and pricing.
Hastelloy G35 screws are manufactured to DIN 933 (hex full thread), DIN 912 (socket cap screws), ISO 4017 (hex head full thread), and ISO 4762 (socket head cap screws) in metric sizes. Inch sizes are produced per ASME B18.2.1 (hex cap screws) and ASME B18.3 (socket head cap screws) in UNC and UNF thread forms. Custom drive types including Torx, Phillips, and slotted heads are available on request with a 15 working day lead time. All screws are machined from ASTM B574 UNS N06035 bar with full EN 10204 3.1 certification.
Hastelloy G35 and C-276 serve different corrosion environments. C-276 (UNS N10276) excels in reducing acid environments and mixed chloride-acid streams due to its higher molybdenum content (15-17%). G35 (UNS N06035) outperforms C-276 in strongly oxidising environments – particularly concentrated nitric acid, mixed HNO3/HF acid, and wet process phosphoric acid – because of its significantly higher chromium content (33.2-36.2% vs 14.5-16.5%). For phosphoric acid plant equipment and nitric acid service, G35 screws are the correct specification. For reducing HCl or H2SO4 service, C-276 remains preferred.
Standard supply condition is bright machined (as-machined) with a natural nickel alloy surface. Additional finishes available include electropolished (Ra = 0.4 µm) for pharmaceutical and food-grade applications, passivated per ASTM A967, and bead-blasted matte finish for reduced light reflection in optical or laboratory environments. All surface treatments are performed after final dimensional inspection and do not affect the base material corrosion resistance. Electropolished screws ship with a separate surface finish certificate.
Yes – Hastelloy G35 screws comply with NACE MR0175/ISO 15156 for sour service applications when supplied in the annealed condition with hardness not exceeding 35 HRC. The alloy’s nickel-chromium-molybdenum composition provides immunity to sulphide stress cracking (SSC) and hydrogen-induced cracking (HIC) in H2S-bearing environments. However, G35 is more commonly specified for oxidising acid and phosphoric acid service rather than pure sour service, where Hastelloy C-276 or Inconel 625 are more cost-effective alternatives. Hardness survey certificates per NACE MR0175 are available on request.

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