20MnV6 Hydraulic Cylinder Tube: An Overview
Sep 22, 2026
20MnV6 hydraulic cylinder tube is a seamless tube of grade 20MnV6 (material number 1.5228, supplied to EN 10297-1) that we finish with a honed bore of ISO H8 tolerance and Ra 0.2–0.4 µm, so it arrives ready to become a 20MnV6 hydraulic cylinder barrel. In the normalized (+N) condition its minimum yield is 470 MPa - about 32% above E355 normalized (355 MPa) - which lets you hold the same pressure in a roughly 25% thinner wall, or carry more pressure at the same wall. The three things this page helps you decide are the delivery condition (+N versus +QT), the wall thickness your pressure actually requires, and whether 20MnV6 is the right step up from E355 for your duty cycle.
20MnV6 is a vanadium-microalloyed carbon-manganese steel. The same grade appears in two standard families that buyers mix up: EN 10297-1 (seamless tubes for mechanical and general engineering) is the parent-tube specification, and EN 10083-3 (heat-treatable steels) covers it as a quench-and-temper grade. It is not an EN 10305-1 grade - that precision-tube standard lists E355, C45E, E470 and similar, but not 20MnV6. When we call a tube a "20MnV6 honed tube," the parent tube answers to EN 10297-1 and the honed bore answers to EN 10305-1 dimensional tolerances. The second half of your decision is the delivery condition: it moves the yield by roughly 120 MPa and the elongation in the opposite direction, so a single number without a condition is not a specification.
We supply 20MnV6 as drawn or hot-finished parent tube, then hone, skive-and-roller-burnish (SRB), or cut and end-finish to your drawing, with an EN 10204 3.1 mill test certificate on every batch. Send us your bore, wall, length and pressure and we will confirm the specification and quote within 24 hours.
Specifications
| Parameter | Capability |
|---|---|
| Parent standard / grade | EN 10297-1 20MnV6 (1.5228); EN 10083-3 |
| Bore ID | 40–500 mm (1.5"–24") |
| Wall thickness | 4–50 mm |
| Length | up to 12 m |
| Bore tolerance | ISO H8 (H9 on request) |
| Surface roughness | Ra 0.2–0.4 µm (honed); Ra 0.05–0.2 µm (SRB) |
| Straightness | ≤0.5 mm/m |
| Delivery condition | +N, +QT, annealed |
| End finish | Plain square-cut, burr-free; machining per drawing |
| Certification | EN 10204 3.1; third-party inspection available |
Tolerance Grade Selection
Pick H8 unless the seal or guide design tolerates H9 - H8 is the hydraulic default and costs little more on a honed bore. Do not "upgrade" to a tighter grade hoping it compensates for a poor cross-hatch; the oil-film geometry matters more than the last micron of diameter.
Straightness, Length and Ends
Keep straightness at ≤0.5 mm/m so the barrel stays round after welding the end cap. For cut-to-length barrels, hold the end squareness your welding fixture expects; we can pre-machine ports and threads per drawing.
Chemical Composition
| Element | Max / range (%) | Why it is controlled |
|---|---|---|
| Carbon (C) | 0.17–0.24 | Strength and weldability balance |
| Silicon (Si) | 0.10–0.50 | Deoxidation; helps machinability |
| Manganese (Mn) | 1.30–1.70 | Hardenability and strength |
| Vanadium (V) | 0.08–0.20 | Grain refinement, yield via microalloying |
| Phosphorus (P) | ≤0.025 | Cold-shortness limit |
| Sulfur (S) | ≤0.020 | Hot-shortness limit (controlled-sulfur 0.015–0.040 available for machining) |
| Cr / Mo / Ni / Cu | ≤0.30 each | Residual limits |
mechanical properties
| Wall t (mm) | +N Yield Rp0.2 (MPa) | +N Tensile Rm (MPa) | +QT Yield (MPa) | +QT Tensile (MPa) |
|---|---|---|---|---|
| ≤16 | 470 | 620–780 | 590 | 700 |
| >16–40 | 460 | 620–780 | 540 | 570 |
| >40–65 | 440 | 620–780 | 480 | 570 |
| >65–80 | 430 | 620–780 | - | - |
| >80–100 | 420 | 620–780 | - | - |
| >100 | 400 | 620–780 | - | - |
What the Bore Carries at Each Wall Thickness
A wall thickness alone tells you nothing about pressure. Use the Lamé bore-yield relation for a thick-walled cylinder, because hoop stress is highest at the bore:
P = ReH · (k²−1) / (k²+1) / S, where k = OD/ID and S is the design factor (4:1 for mobile equipment, 3:1 for some fixed industrial cylinders).
Assumptions for the screening table below: ReH = 470 MPa (+N, thin wall), closed ends, ambient temperature, no corrosion or fatigue allowance, end-cap weld effect ignored. These are filter numbers, not a substitute for cylinder design.
| Bore ID (mm) | Wall (mm) | OD (mm) | k = OD/ID | Working pressure |
|---|---|---|---|---|
| 40 | 5 | 50 | 1.25 | ≈258 bar |
| 63 | 8 | 79 | 1.25 | ≈262 bar |
| 100 | 10 | 120 | 1.20 | ≈212 bar |
| 100 | 20 | 140 | 1.40 | ≈381 bar |
| 160 | 20 | 200 | 1.25 | ≈258 bar |
| 250 | 25 | 300 | 1.20 | ≈212 bar |
| 320 | 30 | 380 | 1.19 | ≈200 bar |
The takeaway competitors miss: "10 mm wall = 350 bar" is only true at about a 50 mm bore. At a 100 mm bore the same 10 mm wall carries about 212 bar - the OD/ID ratio, not the wall, decides. A pressure rating with no bore cannot be checked, so we quote pressure only against your bore and design factor.
Size Boundary and Two Supply Routes
EN 10297-1 covers seamless tubes up to about 720 mm OD and 200 mm wall, which is wider than the honed-tube window most shops hold. For the honed barrel itself, practical limits are ID 40–500 mm, wall 4–50 mm, length ≤12 m. The route that makes the parent tube changes with size:
| Route | Size fit | What it buys you |
|---|---|---|
| Cold drawn, then hone/SRB | ID up to ~168 mm (drawn), tight tolerance, good surface | Best bore consistency for small–mid cylinders |
| Hot finished, then deep-bore + hone | ID up to ~500 mm | Large barrels the cold route cannot reach |
Beyond the honed window, the certificate basis shifts from a precision-tube claim to a machined-component claim, so confirm the inspection scope with the mill rather than assuming an EN 10305-1 tolerance.
Choosing the Delivery Condition
| Service | Recommended condition | Why |
|---|---|---|
| Welded barrel, moderate duty | +N (normalized) | Good weldability, stable yield, lower cost |
| Honed after cold forming (flare, bend) | +N or +A | Retains ductility for post-hone forming |
| High-pressure, thin-wall, uniform hardness | +QT | 480–590 MPa yield, HB 160–205 through wall |
| Heavy stock removal by machining | +QT | Holds dimensions after deep cuts |
Quality Control and Testing
Ultrasonic test of the parent tube before honing, to catch laminar defects that would surface in the bore.
Bore verification - ID at multiple points, Ra by profilometer, cross-hatch angle by visual/standard.
Straightness and roundness over the full length, not just at the ends.
Mechanical check against the 3.1 certificate: yield, tensile, elongation, and hardness for +QT.
Heat-number traceability linking the tube, certificate and any third-party report.
Why Source 20MnV6 Hydraulic Cylinder Tube from GNEE Pipe
Parent-tube and bore finishing under one roof, so the EN 10297-1 grade and the EN 10305-1 bore tolerance are controlled on the same heat number.
EN 10204 3.1 certificate on every batch, with chemistry, mechanicals and bore dimensions matched to the heat.
Stock and custom sizes, cut-to-length and end-machining to drawing, with oil and cap protection for transit.
Third-party inspection (SGS, TÜV, BV) available on request; technical team returns a quote with lead time within 24 hours.
Test and inspection
Packaging and shipping
Send your bore ID, wall, length, delivery condition and working pressure - our technical team will confirm the specification against EN 10297-1 and return a quotation with lead time within 24 hours.
Request a 20MnV6 Hydraulic Cylinder Tube Quote
FAQ
What is 20MnV6 hydraulic cylinder tube?
It is a seamless tube of grade 20MnV6 (material number 1.5228, supplied to EN 10297-1) that has been honed to a mirror-ready bore of ISO H8 tolerance and Ra 0.2–0.4 µm, so it can be cut, welded and fitted directly as a hydraulic cylinder barrel.
What is the yield strength of 20MnV6?
In the normalized (+N) condition the minimum yield is 470 MPa for walls up to 16 mm, stepping down to 400 MPa above 100 mm; quenched and tempered (+QT) raises it to 480–590 MPa by wall thickness. Always quote the delivery condition with the number.
Is 20MnV6 the same as E355?
No. 20MnV6 (1.5228) is a vanadium-alloyed grade with higher strength than E355 (1.0580); they are not interchangeable, and 20MnV6 is not listed in EN 10305-1 while E355 is.
Is 20MnV6 an EN 10305-1 honed tube grade?
No. EN 10305-1 lists E355, C45E, E470 and similar grades but not 20MnV6. A 20MnV6 honed tube uses a parent tube to EN 10297-1 and a honed bore finished to EN 10305-1 dimensional tolerances.
Which delivery condition should I choose for a welded cylinder?
Choose +N (normalized) or +QT; both weld well, with preheat of 100–150 °C when carbon equivalent is near 0.50 or wall exceeds 25 mm. Avoid through-hardened stock for welded barrels and confirm carbon equivalent with the mill.
What wall thickness do I need for my working pressure?
Use P = ReH·(k²−1)/(k²+1)/S with k = OD/ID and S = 4 for mobile equipment. For a 100 mm bore at 10 mm wall in +N (470 MPa) that is about 210 bar. Send us bore, pressure and design factor for a verified figure.
Can 20MnV6 replace 27SiMn or 42CrMo4?
Only at lower duty. 27SiMn (about 835 MPa) and 42CrMo4 (about 930 MPa) suit higher pressure and shock loads; 20MnV6 sits between E355 and those grades and is cheaper to machine and weld.
What certificate and tests come with the tube?
An EN 10204 3.1 mill test certificate with chemistry, mechanical properties and bore dimensions, plus ultrasonic testing, straightness, roundness and surface inspection. Third-party inspection is available on request.
