AISI 4140 vs 4340 Steel: Equivalent Grades Compared
AISI 4140 vs 4340 compared: how 42CrMo and 40CrNiMoA map across ASTM, EN, JIS and ISO, plus chemistry, strength and where each grade fits in service.
Steel Knowledge
Technical guides on Chinese steel grades, international standards and product selection.
Hydrostatic Test for Steel Pipe: Procedure and Purpose
A hydrostatic test proves a steel pipe and its seam hold pressure without leaking. Here is how the test is run, what it proves and how buyers should specify it.
EN 10219 vs EN 10210: Hollow Section Standards Compared
EN 10219 covers cold formed welded hollow sections and EN 10210 covers hot finished ones. Compare the forming route, tolerances and which one to specify.
CE Marking for Structural Steel: What Importers Need to Know
CE marking for structural steel follows the EU Construction Products Regulation and EN 1090. See which standard applies and what importers must check.
EN 10204 3.1 vs 3.2: Which Mill Test Certificate Do You Need?
EN 10204 3.1 and 3.2 certificates report the same test results but are signed by different people. See which inspection document your order actually needs.
Chinese Steel Grades Explained: Q195, Q235 and Q355
The Q in a Chinese steel grade means yield. Here is how Q195, Q235 and Q355 differ, with the actual chemical and mechanical data from our verified database.
EN 10025 S235JR, S275JR and S355JR Explained
The EN 10025 structural steel grades encode yield strength and toughness class in the name. Here is how to read S235JR, S275JR and S355JR and what to specify.
Q355B vs S355JR vs Q235B vs S235JR: Chinese and EN Grade Equivalents
See how the Chinese Q grades line up against the EN S grades, with the actual chemical composition and mechanical properties from our verified grade database.
Deformed Bar vs Round Bar: Which Should You Use for Reinforcement?
Deformed bars bond to concrete; round bars do not. Here is where each is used, with a weight reference table for both, so you can specify the right product.
Hot Rolled vs Cold Rolled Steel: Key Differences for Buyers
Hot rolled and cold rolled steel differ in finish, tolerance, strength and cost. Here is how to pick the right one for your application and how to specify it.
H Beam vs I Beam: Differences, Uses and How to Specify
H beams and I beams look similar but behave differently. Here is how the two shapes differ, where each is used, and how to specify the right one.
Galvanized vs Mild Steel: Which Should You Choose?
Galvanized steel is mild steel with a zinc coating. The choice comes down to corrosion exposure, cost and whether the surface can be coated at all.