Steel E355 · supply condition
Steel E355-HR
Properties of the HR condition, compared with the other E355 tempers.
Cheapest form for heavy-wall structural tube and bar where dimensional precision and surface finish are not critical.
What is E355-HR?
E355-HR is E355 supplied in the HR condition — cheapest form for heavy-wall structural tube and bar where dimensional precision and surface finish are not critical. E355-HR has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 67% of steel grades. Elongation at break is 22% and the elastic modulus is 210 GPa (30.5 Msi). E355-HR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,460°C (2,660 °F). CD is the default condition FabDigit quotes; HR is available on request or by drawing note.
Advantages
- Readily welded — 78/100, better than 78% of steel grades
- Forms and bends easily — 62/100, better than 78% of steel grades
Limitations
- Low fracture toughness — 60 MPa·√m (54.6 ksi·√in), worse than 79% of steel grades
E355-HR properties
Typical room-temperature values for E355-HR — 14 properties are specific to this condition; the rest are grade-level values shared by every E355 temper. Each bar shows where the value sits among the steel grades in FabDigit's library — further right is higher.
Physical3
E355-HR has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,460°C (2,660 °F).
Mechanical16
E355-HR has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 67% of steel grades. Elongation at break is 22% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
E355-HR is rated for continuous service to 350°C (662 °F). It conducts heat at 45 W/m·K (26 BTU/hr·ft·°F), better than 66% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
E355-HR conducts electricity at 8.6 % IACS, better than 66% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 87% of steel grades.
Sustainability4
Producing a kilogram of E355-HR takes about 25 MJ of energy and emits 2 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 25%.
Manufacturability6
E355-HR's machinability is fair (52/100, better than 52% of steel grades); weldability very good (78/100); formability good (62/100).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other E355 tempers and conditions
E355 is also supplied in 7 other conditions. The full side-by-side table is on the E355 overview.
- CDDefaultDefault stocked condition: cold-drawn precision tube/bar with tight tolerance and good surface, used for hydraulic cylinders and structural tubing.490 MPa yield · 190 HB
- CHighest strength/hardness and best surface, but low ductility and high residual stress — avoid where machining-induced distortion matters.620 MPa yield · 210 HB
- SRStandard hydraulic-cylinder tube condition: cold-drawn accuracy with residual stress removed so the tube stays straight after machining or honing.490 MPa yield · 185 HB
- SRBReady-to-use hydraulic cylinder barrel: ID machined and roller burnished to H8/H9 with Ra 0.2–0.4 µm; mechanicals follow the underlying +SR/+N tube.480 MPa yield · 185 HB
- LCPrecision cold-drawn dimensions with retained ductility — for tubes that will still be bent or flanged after drawing.400 MPa yield · 165 HB
- HRCheapest form for heavy-wall structural tube and bar where dimensional precision and surface finish are not critical.380 MPa yield · 160 HB
- NPick when uniform fine-grain structure, guaranteed 355 MPa yield and -20 °C impact toughness are required (pressure and structural service).380 MPa yield · 155 HB
- ASoftest condition — choose for heavy cold forming, bending, flaring or deep upsetting of the tube/bar before final heat treatment.290 MPa yield · 135 HB
Working with E355-HR
Is E355 easy to machine?
Machines like a 0.2 %C C-Mn steel (~60 % of 1212); cold-drawn +C/+SR chips break better than annealed stock, use carbide at 150–220 m/min with coolant and expect some spring-back/distortion when heavy stock is removed from +C tube.
Can E355 be welded?
Readily welded by MAG/SAW/TIG with G3Si1/ER70S-6 class filler; CEV ≈ 0.40–0.45 so preheat 100–150 °C for wall thicknesses above ~30 mm or in restrained joints, and re-normalize if full toughness is needed.
Can E355 be formed, bent or molded?
+A and +LC bend, flare and expand well (bend radius ≥ 2×D); +C hard-drawn tube has only 4–6 % elongation and should be stress relieved or annealed before cold forming; hot forming at 850–1050 °C followed by normalizing.
What surface finishes work on E355?
No inherent corrosion resistance — specify phosphate + oil, zinc plating, paint or hard-chrome/CrN on piston rods; ID of cylinder tube is roller-burnished or honed to Ra 0.2–0.4 µm; it takes nitriding and induction hardening only modestly due to low carbon.
E355 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Ccast analysis, EN 10305-1 | ≤ 0.22 | 0.18 |
| Si | ≤ 0.55 | 0.25 |
| Mn | ≤ 1.6 | 1.3 |
| P | ≤ 0.03 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Altotal Al for fine-grain/killed practice, when specified | ≥ 0.02 | 0.03 |
| Fe | balance | — |
E355-HR — frequently asked
What is E355-HR used for?
E355-HR is typically used for hydraulic cylinder tube, piston and hydraulic rods, crane jibs and telescopic booms, industrial structures and frames, pneumatic cylinder barrels and roller and axle tube. In short: precision hydraulic tube.
What is the yield strength of E355-HR?
E355-HR has a typical yield strength of 380 MPa (55.1 ksi) and a tensile strength of 560 MPa (81.2 ksi) — weaker than 67% of steel grades. Strength varies by condition: see the 8 listed tempers.
Is E355-HR easy to machine?
Reasonably — machinability is rated fair (52/100, better than 52% of steel grades). Machines like a 0.2 %C C-Mn steel (~60 % of 1212); cold-drawn +C/+SR chips break better than annealed stock, use carbide at 150–220 m/min with coolant and expect some spring-back/distortion when heavy stock is removed from +C tube.
Can E355-HR be welded?
Yes — weldability is rated very good (78/100). Readily welded by MAG/SAW/TIG with G3Si1/ER70S-6 class filler; CEV ≈ 0.40–0.45 so preheat 100–150 °C for wall thicknesses above ~30 mm or in restrained joints, and re-normalize if full toughness is needed.
What surface finishes work on E355-HR?
No inherent corrosion resistance — specify phosphate + oil, zinc plating, paint or hard-chrome/CrN on piston rods; ID of cylinder tube is roller-burnished or honed to Ra 0.2–0.4 µm; it takes nitriding and induction hardening only modestly due to low carbon.
Can E355-HR be formed, bent or molded?
+A and +LC bend, flare and expand well (bend radius ≥ 2×D); +C hard-drawn tube has only 4–6 % elongation and should be stress relieved or annealed before cold forming; hot forming at 850–1050 °C followed by normalizing.
What is the maximum service temperature of E355-HR?
E355-HR is rated for continuous use to about 350°C (662 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between E355-CD and E355-A?
CD is the default condition — default stocked condition: cold-drawn precision tube/bar with tight tolerance and good surface, used for hydraulic cylinders and structural tubing. A: softest condition — choose for heavy cold forming, bending, flaring or deep upsetting of the tube/bar before final heat treatment. Yield strength is 490 MPa in CD versus 290 MPa in A.
Can FabDigit make parts in E355-HR?
Yes — E355-HR is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- EN 10305-1 Steel tubes for precision applications — Seamless cold drawn tubes — CEN (2016)
- EN 10297-1 Seamless circular steel tubes for mechanical and general engineering purposes — CEN (2003)
- EN 10027-2 Designation systems for steels — Numerical system (1.0580) — CEN (2015)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- Machinery's Handbook, 31st ed. (machinability and hardness conversion) — Industrial Press (2020)
- Hydraulic cylinder tube (E355 +SR / SRB) product data — European seamless tube producers (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.