From the Engineers

Technical Insights

Practical guides on fastener grade selection, PED compliance, coatings and industry standards — written by LOKRON engineers.

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Materials

ASTM A194 Grade 8 Stainless Steel Nuts: Selection & Procurement Guide

Learn how to specify ASTM A194 Grade 8 Type 304 stainless steel nuts, distinguish Grade 8M and 2H, and verify dimensions, testing, marking, and traceability.

2026-08-118 min read
ASTM A194 Grade 8Type 304 stainless steelheavy hex nuts
Applications

Heat Exchanger Bolting: B8 vs B8M, PMI, and EN 10204 3.1 Docs

Selecting ASTM A193 B8 vs B8M for corrosive heat exchanger service: chloride limits, Class 1 vs 2, PMI verification, and EN 10204 3.1 documentation.

2026-08-1012 min read
ASTM A193 B8ASTM A193 B8MPMI
Applications

Industrial Valve Fasteners: Selection Guide for Process Plant Bolting

Learn how to select industrial valve fasteners for process plants. Covers ASTM A193 B7/B7M/B16 studs, A194 nuts, preload, NACE compliance, and procurement checklist.

2026-08-0412 min read
valve fastenersASTM A193 B7ASTM A194 2H
Applications

Ultrasonic Bolt Load Verification: How It Works and Why It Matters for Flange Integrity

Learn how ultrasonic bolt load verification ensures accurate preload in bolted flanges, reduces leakage risk, and outperforms traditional torque and tension methods.

2026-07-198 min read
ultrasonic bolt load verificationflange integritybolt tension measurement
Applications

Stud Bolt Torque Chart for B7, B8, B8M, L7 Materials: Preload & Lubrication Guide

Comprehensive stud bolt torque chart for ASTM A193 B7, B8, B8M, and A320 L7 materials. Includes preload formulas, lubrication factors, and free PDF download.

2026-07-1712 min read
stud bolt torque chartB7 torque valuesB8 torque values
Standards & Compliance

Types of Stud Bolts: Full Thread vs. Half Thread vs. Double-End Studs

Compare full thread, half thread, and double-end stud bolts for flanges, pressure vessels, and valves. Learn selection criteria based on load, assembly, and standards like ASTM A193.

2026-07-1612 min read
stud boltsfull threadhalf thread
Applications

Stud Bolts for Flanges: Selection Guide for ASME B16.5 & EN 1092

Comprehensive guide to selecting stud bolts for flanged connections per ASME B16.5 and EN 1092. Covers dimensions, materials (B7, B8, B16), torque recommendations, and common mistakes.

2026-07-1412 min read
stud boltsflange boltingASME B16.5
Applications

How to Calculate Bolt Pretension for Flange Connections: A Step-by-Step Guide

Learn how to calculate bolt pretension for flange connections using torque and tension methods. Includes formulas, examples, and factors affecting preload for ASTM A193 stud bolts.

2026-06-258 min read
bolt pretensionflange connectiontorque calculation
Standards & Compliance

ASTM A193 B8 Class 1 vs Class 2 Stud Bolts: Complete Comparison

Detailed comparison of ASTM A193 B8 Class 1 and Class 2 stud bolts: chemical composition, mechanical properties, corrosion resistance, and application guidelines for oil & gas and petrochemical industries.

2026-06-218 min read
ASTM A193 B8Class 1 vs Class 2stud bolts
Standards & Compliance

ASTM A320 L7 Low-Temperature Stud Bolts: Complete Technical Guide

Comprehensive guide to ASTM A320 L7 stud bolts: chemical composition, mechanical properties, low-temperature impact testing, comparison with L7M and B7, and procurement tips with EN 10204 3.1 certification.

2026-06-1912 min read
ASTM A320 L7low-temperature stud boltsL7 vs L7M vs B7
Standards & Compliance

API 6A Threading for Stud Bolts: Specifications and Best Practices

Comprehensive guide to API 6A threading for stud bolts: thread types, dimensions, materials, inspection, and applications in wellhead equipment for oil and gas.

2026-06-1810 min read
API 6Astud boltsthreading
Standards & Compliance

ASTM A193 B7 vs A320 L7: Selection Guide for Low-Temperature vs High-Temperature Service

Compare ASTM A193 B7 and A320 L7 stud bolts for high-temperature and low-temperature service. Learn chemical composition, mechanical properties, and certification requirements.

2026-06-158 min read
ASTM A193 B7ASTM A320 L7low temperature fasteners
Manufacturing

Custom Stud Bolts for HPHT Applications: Materials, Standards, and Lead Times

Learn how custom stud bolts for high-pressure high-temperature (HPHT) applications are engineered. Material selection (A193 B16, Inconel 625), threading options, certifications (PED, NACE, API 20E/20F), and lead times explained.

2026-06-1312 min read
HPHTstud boltsA193 B16
Manufacturing

Custom Stud Bolts for Oil & Gas: Specifications, Lead Times, and Certification

Learn about custom stud bolts for oil & gas: common modifications, material grades, lead times, MOQs, and certification options (PED, NACE, API). How to request a quote from LOKRON.

2026-06-128 min read
custom stud boltsoil and gas fastenersASTM A193
Applications

Bolt Torque Calculator: Free Online Tool for Flange Bolting

Use our free online bolt torque calculator for flange bolting. Learn the T=KDF formula, input bolt size, grade, and lubrication condition to get accurate torque values. Includes example and FAQ.

2026-06-108 min read
bolt torque calculatorflange boltingT=KDF
Standards & Compliance

ASTM A193 B16 High-Temperature Bolting: Complete Technical Guide

Comprehensive guide to ASTM A193 B16 high-temperature bolting: chemical composition, mechanical properties, temperature limits, comparison with B7 and B8, and procurement tips for oil & gas and petrochemical applications.

2026-06-0612 min read
ASTM A193 B16high-temperature boltingstud bolts
Standards & Compliance

ASTM A193 B7 vs B8 vs B16: Complete Selection Guide for Stud Bolts

Compare ASTM A193 B7, B8, and B16 stud bolts by temperature range, corrosion resistance, and application fit for critical industrial service.

2026-06-0112 min read
ASTM A193B7B8
Standards & Compliance

NACE MR0175 Fasteners: Compliance Guide for Sour Service

Comprehensive guide to NACE MR0175/ISO 15156 fastener requirements for sour service. Learn about material selection, hardness limits, heat treatment, and certification for ASTM A193 B7M, L7M, and more.

2026-05-2512 min read
NACE MR0175ISO 15156sour service
Standards & Compliance

ASTM A193 B7 Stud Bolt: Specifications, Properties, and Applications

Comprehensive guide to ASTM A193 B7 stud bolts: material composition, mechanical properties, typical applications in oil & gas flange connections, comparison with B8 and B16, and procurement tips.

2026-05-228 min read
ASTM A193 B7stud boltmechanical properties
Technical Guide

ASTM A320 L7 and L7M: Specifying Fasteners for Cryogenic and Low-Temperature Service

Understanding ASTM A320 L7 and L7M grades for LNG, ethylene plants and air separation units — covering ductile-to-brittle transition, Charpy impact testing requirements, and NACE compliance for sour cryogenic service.

2026-05-1211 min read
ASTM A320L7L7M
Technical Guide

Bolt Torque vs Tension: Achieving Flanged Joint Integrity in Critical Service

Torque alone is unreliable as a bolt load measure. ASME PCC-1 guidelines, K-factor management, and proper joint assembly are essential for reliable sealing in critical industrial flanges.

2026-05-1011 min read
torquetensionflange assembly
Industry Knowledge

MRO Fastener Procurement: Reducing Cost and Risk for Distributors and Industrial Buyers

Practical guidance for MRO distributors and industrial procurement teams on managing counterfeit risk, documentation compliance, and building resilient fastener supply chains.

2026-05-018 min read
MROprocurementcounterfeit
Standards & Compliance

EN 14399 High-Strength Structural Bolting: HV and HR Systems Explained

Understanding EN 14399 high-strength structural bolting systems for steel construction — HV vs HR systems, preloading methods, CE marking requirements, and differences from ASTM A325/A490.

2026-04-288 min read
EN 14399structural boltingHV
Standards & Compliance

ASME B16.5 Flange Bolt Selection: Stud Count, Grade and Length by Pressure Class

Complete guide to ASME B16.5 flange bolting requirements — stud count tables, bolt diameter and length by NPS and pressure class, thread engagement rules, and stud projection requirements.

2026-04-209 min read
ASME B16.5flangepressure class
Applications

Fasteners for API 6A Wellhead Equipment: Material, Testing and Traceability Requirements

Comprehensive technical guide to fasteners for api 6a wellhead equipment: material, testing and traceability requirements, covering specifications, material selection, applications, and LOKRON supply capabilities.

2026-04-1010 min read
API 6Awellheadoil & gas
Applications

Fasteners in Hydrogen Service: Preventing Hydrogen-Induced Cracking and SOHIC

Comprehensive technical guide to fasteners in hydrogen service: preventing hydrogen-induced cracking and sohic, covering specifications, material selection, applications, and LOKRON supply capabilities.

2026-04-0511 min read
hydrogen serviceHICSOHIC
Applications

Valve OEM Stud Bolt Specification Guide: From ASME B16.5 Class 150 to 2500

Comprehensive technical guide to valve oem stud bolt specification guide: from asme b16.5 class 150 to 2500, covering specifications, material selection, applications, and LOKRON supply capabilities.

2026-03-309 min read
valve OEMstud boltASME B16.5
Compliance

PED 2014/68/EU: What It Means for Fastener Procurement in Europe

Understanding the Pressure Equipment Directive and why PED-certified fasteners are legally required for pressure equipment in EU markets. Full procurement checklist included.

2026-03-2010 min read
PEDEU compliancepressure equipment
Applications

High-Temperature Fastener Selection for Shell-and-Tube Heat Exchangers

Comprehensive technical guide to high-temperature fastener selection for shell-and-tube heat exchangers, covering specifications, material selection, applications, and LOKRON supply capabilities.

2026-03-1510 min read
heat exchangerhigh temperatureB16
Applications

Bolting Challenges in Petrochemical Reactor Design: Alloy Selection and Relaxation Management

Comprehensive technical guide to bolting challenges in petrochemical reactor design: alloy selection and relaxation management, covering specifications, material selection, applications, and LOKRON supply capabilities.

2026-03-0511 min read
reactorpetrochemicalalloy selection
Technical Guide

Fastener Coatings for Outdoor & Offshore: Hot-Dip Galvanising vs PTFE/Xylan

Comparing hot-dip galvanising and PTFE (Xylan) coatings for high-strength stud bolts — corrosion protection levels, galling prevention, and LOKRON's coating selection guide.

2026-02-289 min read
coatingHDGPTFE
Coatings & Corrosion

Electroless Nickel Plating on Industrial Fasteners: Properties, Applications and Process Control

Comprehensive technical guide to electroless nickel plating on industrial fasteners: properties, applications and process control, covering specifications, material selection, applications, and LOKRON supply capabilities.

2026-02-209 min read
electroless nickelENPcoating
Coatings & Corrosion

Galling in Stainless Steel Fasteners: Mechanism, Prevention and Field-Proven Solutions

Comprehensive technical guide to galling in stainless steel fasteners: mechanism, prevention and field-proven solutions, covering specifications, material selection, applications, and LOKRON supply capabilities.

2026-02-108 min read
gallingstainless steelB8
Coatings & Corrosion

Duplex Coating Systems for Offshore Fasteners: HDG+PTFE and NORSOK M-501 Compliance

Comprehensive technical guide to duplex coating systems for offshore fasteners: hdg+ptfe and norsok m-501 compliance, covering specifications, material selection, applications, and LOKRON supply capabilities.

2026-02-019 min read
duplex coatingoffshoreNORSOK
Quality & Inspection

EN 10204 Mill Certificates Explained: Type 2.2 vs 3.1 vs 3.2 — What Your Project Needs

Comprehensive technical guide to en 10204 mill certificates explained: type 2.2 vs 3.1 vs 3.2 — what your project needs, covering specifications, material selection, applications, and LOKRON supply capabilities.

2026-01-258 min read
EN 10204mill certificateMTR
Quality & Inspection

Hydrogen Embrittlement in Electroplated Fasteners: ASTM F1941 Baking Requirements

Comprehensive technical guide to hydrogen embrittlement in electroplated fasteners: astm f1941 baking requirements, covering specifications, material selection, applications, and LOKRON supply capabilities.

2026-01-159 min read
hydrogen embrittlementelectroplatingASTM F1941
Quality & Inspection

Positive Material Identification (PMI) Testing for Fasteners: When to Specify and What to Expect

Comprehensive technical guide to positive material identification (pmi) testing for fasteners: when to specify and what to expect, covering specifications, material selection, applications, and LOKRON supply capabilities.

2026-01-058 min read
PMIXRFmaterial identification
Industry Knowledge

Counterfeit Fastener Detection: A Buyer's Complete Inspection and Verification Guide

Comprehensive technical guide to counterfeit fastener detection: a buyer's complete inspection and verification guide, covering specifications, material selection, applications, and LOKRON supply capabilities.

2025-12-1010 min read
counterfeitfastener inspectionfraud
Industry Knowledge

Total Cost of Ownership for Industrial Fasteners: Why Lowest Price Costs Most

Comprehensive technical guide to total cost of ownership for industrial fasteners: why lowest price costs most, covering specifications, material selection, applications, and LOKRON supply capabilities.

2025-12-018 min read
TCOtotal costprocurement
Industry Knowledge

How to Qualify a Fastener Supplier for the Process Industries: A Step-by-Step Framework

Comprehensive technical guide to how to qualify a fastener supplier for the process industries: a step-by-step framework, covering specifications, material selection, applications, and LOKRON supply capabilities.

2025-11-2010 min read
supplier qualificationauditISO 9001
Industry Knowledge

Lot Traceability and Heat Number Management in Industrial Fastener Supply Chains

Comprehensive technical guide to lot traceability and heat number management in industrial fastener supply chains, covering specifications, material selection, applications, and LOKRON supply capabilities.

2025-11-109 min read
traceabilityheat numberlot control
Custom Manufacturing

Special Alloy Fasteners: Inconel 625, Incoloy 825 and Duplex 2205 for Extreme Service

Comprehensive technical guide to special alloy fasteners: inconel 625, incoloy 825 and duplex 2205 for extreme service, covering specifications, material selection, applications, and LOKRON supply capabilities.

2025-11-0111 min read
Inconel 625Incoloy 825Duplex 2205
Custom Manufacturing

Custom Fastener Manufacturing at LOKRON: From Engineering Drawing to First Article Inspection

Comprehensive technical guide to custom fastener manufacturing at lokron: from engineering drawing to first article inspection, covering specifications, material selection, applications, and LOKRON supply capabilities.

2025-10-259 min read
custom fastenerOEMODM
Custom Manufacturing

Stud Bolts vs Hex Bolts vs Cap Screws: A Design Engineer's Selection Guide for Pressure Equipment

Comprehensive technical guide to stud bolts vs hex bolts vs cap screws: a design engineer's selection guide for pressure equipment, covering specifications, material selection, applications, and LOKRON supply capabilities.

2025-10-158 min read
stud bolthex boltcap screw
Custom Manufacturing

Foundation and Anchor Bolt Specification: ASTM F1554, J-Bolts and Headed Anchor Applications

Comprehensive technical guide to foundation and anchor bolt specification: astm f1554, j-bolts and headed anchor applications, covering specifications, material selection, applications, and LOKRON supply capabilities.

2025-10-0110 min read
anchor boltfoundation boltASTM F1554
Technical Guide

Thread Forms in Industrial Fasteners: UNC/UNF, Metric, BSP and Special Profiles Compared

Comprehensive comparison of industrial thread systems — Unified (UNC/UNF), ISO Metric, BSP (British Standard Pipe), ACME and trapezoidal threads, including why mixing standards causes catastrophic failures.

2025-09-209 min read
thread formUNCUNF

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