Technical Blog — Page 3

On German chemical plant projects and AD 2000 pressure equipment, you will encounter EN 1.4571 far more often than 1.4404. Understanding why — and how it…

Grade 321 (EN 1.4541 / ASTM WP321) is specified when piping will be exposed to the sensitisation temperature range — 425 to 850°C — during operation…

Incoloy 825 (EN 2.4858 / UNS N08825) bridges the gap between 904L stainless steel and the premium nickel alloys. It is specified where 904L is insufficient…

Desalination plants handle seawater, brine concentrate, and chemical dosing in high-temperature, high-pressure cycles — some of the most corrosive…

A chlor-alkali plant electrolyses brine to produce three co-products simultaneously: wet chlorine gas, sodium hydroxide (caustic soda) solution, and…

Copper-nickel alloys — 90/10 (90% Cu, 10% Ni, UNS C70600) and 70/30 (70% Cu, 30% Ni, UNS C71500) — are the standard materials for seawater piping and pipe…

When flue gas from sulphur-bearing fuels cools below the sulphuric acid dew point — typically 120–160°C depending on SO₃ concentration — concentrated H₂SO₄…

Hydrofluoric acid (HF) service is one of the most specialised and hazardous applications for pipe fittings. HF alkylation units — used in refineries…

Nickel alloys used for pipe fittings — Inconel 625, Hastelloy C-276, Alloy 825 — solidify from the melt with significant dendritic microsegregation. The…

High-nickel alloys are well known for their resistance to chloride stress corrosion cracking — a property that makes them the material of choice for…

Pipe fittings for oxygen service — medical oxygen distribution, industrial oxygen in steel manufacturing, liquid oxygen (LOX) in cryogenic plant, and…

Phosphoric acid (H₃PO₄) is the fourth-largest volume chemical produced globally, primarily as an intermediate in fertiliser manufacture. The corrosion

Titanium pipe fittings are specified for highly corrosive services where both stainless steel and most nickel alloys are inadequate — wet chlorine…

Weld overlay deposits a corrosion-resistant alloy layer on a carbon or low-alloy steel substrate, combining structural strength with corrosion…

Zirconium and tantalum are the two metals with the broadest corrosion resistance in strong acid service — significantly outperforming nickel alloys…

Incoloy 825 vs Inconel 625 fittings: composition, chloride and acid resistance, ISO 15156-3 sour limits, strength, weldability and when each is justified.

Metal dusting is a catastrophic high-temperature corrosion mechanism that converts solid metal into a powdery mixture of metal, carbides, and carbon…

Inconel 601 (EN 2.4851, UNS N06601) is a nickel-chromium alloy with a controlled aluminium addition (1.0–1.7%) that produces a strongly adherent Al₂O₃-rich…

Hastelloy C-276 is the most versatile corrosion-resistant nickel alloy — but in pure reducing acid environments (concentrated HCl, H₂SO₄ above 80%), its…

Alloy 20 (UNS N08020, ASTM B366 WPNC) was specifically engineered for hot sulphuric acid service — a corrosive environment that defeats 316L and challenges…

Incoloy 800H (UNS N08810, EN 1.4876) is the high-carbon, grain-coarsened variant of the Incoloy 800 family, specifically designed to maximise creep…

Monel 400 (EN 2.4360, UNS N04400) is a 67% Ni – 30% Cu solid-solution alloy with a unique combination of corrosion resistance in hydrofluoric acid…

Inconel 600 (EN 2.4816 / UNS N06600) is a 76Ni-15Cr-8Fe nickel-chromium alloy designed specifically for oxidising environments at extreme temperatures — up…

Ni-Cr-Mo alloy selection for pipe fittings: Hastelloy C-276 vs C-22, C-4 for thermal stability, C-2000 and Alloy 59, and Inconel 625 vs C-276.

Acoustic-induced vibration (AIV) is a fatigue failure mechanism in pipe fittings and piping downstream of high-pressure-drop gas-service components…

AD 2000-Merkblatt (Arbeitsgemeinschaft Druckbehälter — Pressure Vessel Committee) is a German technical rules series for pressure equipment design…

Not all pipe fittings are buttweld fittings. ASME B16.11 covers forged socket weld and threaded fittings — a completely different product family from…

Long radius (LR) elbows to ASME B16.9 — with a centre-to-end dimension equal to 1.5 times the nominal pipe size — are the default for the vast…

ASME B31.3 Process Piping Code classifies piping by fluid service category. Most engineers are familiar with normal fluid service, but Category D…

Preheat — heating the pipe fitting and adjacent pipe before welding — is the primary control for preventing cold cracking (hydrogen-assisted HAZ cracking)…

A fitting that passes material certification can still fail in service or cause fabrication problems if it is dimensionally out of tolerance…

Forged (ASME B16.11), wrought buttweld (ASME B16.9) and cast pipe fittings compared: manufacturing routes, grain flow, properties and when to specify each.

Pressure testing is the final integrity verification for a pipe fitting assembly before commissioning — it demonstrates that the system can sustain…

An Inspection and Test Plan (ITP) is a document that defines, for each stage of pipe fitting manufacture and inspection, what activity is performed, what…

Liquid penetrant testing (PT) and magnetic particle testing (MT) are both surface examination methods used to detect open surface discontinuities on pipe…

Manganese sulphide (MnS) inclusions are an inherent feature of conventional carbon steel produced without specific sulphur control. These elongated…

An EN 10204 material test certificate is not just a document — it is the legal and technical proof that the fitting in your hand was manufactured from

MDMT and Charpy impact testing for carbon steel and LTCS pipe fittings: ASME B31.3 exemption curves, ASME and EN acceptance values, WPL6, and PO wording.