What “Sour Service” Means A gas or multiphase stream is considered sour when the H2S partial pressure is at least 0.05 psia (≈ 0.34 kPa) at the operating conditions defined in NACE MR0175 / ISO 15156. In sour environments, wet H2S drives sulfide stress cracking (SSC) and hydrogen-induced cracking (HIC) in hard or segregated microstructures […]
The Standard Formula The weight of a carbon steel pipe per metre is calculated from its OD and wall thickness: W (kg/m) = (OD − WT) × WT × 0.02466, with OD and WT in millimetres. The constant comes from the steel density of 7,850 kg/m³: a hollow cylinder’s cross-sectional area times density. For lb/ft,
Two Nominal Systems, One Pipe NPS (Nominal Pipe Size, inches) is used in ASME-based markets; DN (Diamètre Nominal, mm) is the metric ISO/EN designation. Both are nominal — neither equals the actual OD exactly, except from NPS 14 upward, where NPS happens to equal the OD in inches. NPS (in) DN (mm) Actual OD (mm)
Why Alloy Boiler Tubes Exist As steam pressure and metal temperature rise, carbon steel loses creep strength and oxidizes rapidly. Chromium-molybdenum alloy tubes add creep resistance and oxidation resistance, which is why ASME SA213 (tube) and SA335 (pipe) grades dominate superheater, reheater and boiler circulation circuits in power and process plants. ASME Grade Chemistry Common
What Is OCTG? OCTG (Oil Country Tubular Goods) covers the casing and tubing that make up an oil or gas well, manufactured to API Spec 5CT. Casing lines the borehole; tubing carries the produced fluid to surface. Unlike line pipe (API 5L), OCTG is selected by yield strength and connection integrity as much as by
Favorable Factors: 1. Raw material costs surged — coke multiple hikes, coking coal futures rallied, iron ore firmed — lifting the cost floor for pipe prices. 2. Supply tightened as mills cut output amid production controls, strengthening pricing power. 3. Policy support (capacity curbs, infrastructure plans) reinforced market confidence. 4. Peak season anticipation boosted futures-led
Favorable Factors: 1. Raw material costs are climbing, as upstream billet and hot-rolled strip prices continue to trend upward, providing strong cost support for pipe manufacturers. 2. Market sentiment is getting a boost from mainstream product price hikes, giving mills the confidence to hold and push up their quotations. Adverse Factors: 1. End-user demand remains
Favorable Factors: 1. Mill inventories are staying relatively low, giving pipe manufacturers the leverage to push up ex-factory prices even when downstream demand is soft. 2. Raw material costs for hot-rolled strip steel and steel billets have shown resilience, creating a solid cost floor that supports the upward movement of finished pipe prices. 3. Upstream
Favorable Factors: 1. Raw material costs for hot rolled strip steel have shown minor fluctuations, providing a stable baseline for pipe manufacturing expenses. 2. Steel futures have experienced slight recoveries, which helps stabilize market sentiment and prevents aggressive price drops. 3. Pipe mills are maintaining steady production without concentrated shutdowns, ensuring a reliable supply chain
Favorable Factors: 1. Steel billet prices showed signs of stabilization recently, providing a temporary floor for raw material costs. 2. Some local pipe mills maintained steady output prices despite broader market declines, indicating a reluctance to aggressively cut margins. Adverse Factors: 1. The traditional off-season continues to weigh heavily on downstream demand, with end-users only