Honed Tube vs SRB Tube: Which Bore-Finishing Process Should You Specify?

Honed tube and SRB tube can both provide a precision bore for hydraulic cylinders, but they create that bore in different ways. Honing is an abrasive cutting process that can correct bore geometry and generate a cross-hatched texture. Skiving and roller burnishing (SRB) cuts the bore to size and then plastically smooths the peaks, making it especially attractive for repeatable, high-volume production.

Honing and skiving roller burnishing processes for hydraulic cylinder tubes

The best specification is not “the smoothest process.” It is the process that reliably delivers the diameter, form and functional surface required by the seal system at the project’s volume and cost. New Star Steel supplies hydraulic cylinder tube in process routes matched to the drawing and application.

How each process works

During honing, abrasive stones contact the bore while the tool rotates and reciprocates. The controlled overlap helps improve size, roundness, straightness and surface texture. Honing can be applied to new tubes and to bores that need corrective finishing.

SRB combines two operations. Skiving removes a controlled layer to establish bore size and geometry. Roller burnishing then presses the surface peaks, producing a smoother, work-hardened near-surface layer without a second abrasive operation. ECOROLL’s process description explains this cutting-and-forming sequence.

Honed tube vs SRB tube at a glance

Decision factor	Honed tube	SRB tube
Finishing principle	Abrasive material removal	Skiving followed by plastic smoothing
Typical visual texture	Controlled cross-hatch	Very smooth, plateau-like burnished surface
Geometry correction	Flexible for correcting bore form	Strong repeatability when starting stock and setup are controlled
Productivity	Usually lower material-removal rate	Often faster for long production runs
Surface modification	Cuts the surface	Burnishing can raise bearing area and strain-harden the surface layer
Best choice	Complex correction, service work, controlled cross-hatch	High-volume new production and efficient one-pass finishing

Do not select by Ra alone

Arithmetic roughness is useful, but it compresses a complex surface into one number. Two bores can share the same Ra while having different peak sharpness, valley depth, waviness and material ratio. Those differences can change break-in behavior, lubricant retention and seal wear.

SKF’s hydraulic seal guidance treats honed and roller-burnished bores as functional counter-surfaces and recommends evaluating several roughness parameters. The practical lesson is simple: obtain the seal supplier’s counter-surface specification, then require the tube producer to report the relevant measurements.

When honing is usually the safer choice

The starting bore needs meaningful correction for taper, waviness or local geometry.
The seal design calls for a controlled cross-hatch or plateau-honed texture.
The volume is moderate and flexibility matters more than maximum throughput.
The tube is part of a repair, prototype or special-size program.
Stock removal must be adjusted after upstream machining variation is measured.

When SRB usually has the advantage

Production volume is high and cycle time is commercially important.
The starting tube has consistent wall and bore geometry.
A high-bearing-area, low-friction surface is approved by the seal supplier.
Long, repeatable cylinder barrels are required.
The producer has stable skiving tools, burnishing setup and in-process control.

ECOROLL reports that combined skiving and burnishing can achieve dimensionally accurate bores with low roughness in one process chain. Those published tool capabilities are useful engineering references, but a purchase order should still state acceptance limits rather than relying on a process name.

What to put on the drawing and purchase order

Specify material grade and standard, delivery condition, nominal finished ID with upper and lower limits, OD and wall requirements, roundness or cylindricity where necessary, straightness, surface parameters, length, end condition, cleanliness and corrosion protection. Add sample frequency and report format for dimensional and roughness inspection.

If the drawing says only “honed” or “SRB,” suppliers may quote different acceptance levels. A complete functional specification gives you comparable offers.

Frequently asked questions

Is SRB always smoother than honing?

Not necessarily. Both processes cover a range of finishes. The result depends on tooling, stock allowance, material, machine stability and the measurement method.

Can SRB replace honing in every cylinder?

No. It is a highly productive option, but blind bores, repair work, unusual geometry, starting-stock variation or a specified cross-hatch may favor honing.

Which process gives longer seal life?

Seal life depends on the complete tribological system: surface texture, hardness, alignment, pressure, speed, lubrication, contamination and seal material. Process name alone cannot guarantee life.

For material selection, continue with E355 vs ST52 vs SAE 1026. For a drawing review and quotation, contact New Star Steel.