Cylinder tubes

Hydraulic tubes with wear-resistant surfaces for long life and reliability.

Flexible tubes for maximum life span

In collaboration with several leading manufacturers of hydraulic systems, Structo have developed a broad, competitive range of roller burnished cylinder tubes.

The properties of the cylinder tubes are specially developed for maximum reliability in operations with minimal wear on the cylinder’s seals. The tubes are manufactured of CDS tubes, which are also manufactured in Structo’s facilities.

Cylinder tubes are stocked in many standard dimensions and also in custom lengths and formats – for delivery at agreed times. The tubes can also be delivered at fixed lengths with varying degrees of refinement.

Mechanical characteristics

Steel grade
Condition
Yeald strenght Rp0,2
[Mpa (N/mm²)]
Tensile strenght Rm [Mpa (N/mm²)]
Elongation A%
Impact toughness KV [J] @ -20°C
Hardness

Structo 525

+SR

525

600

15

**

*

Structo 620

+SR

620

700

15

**

*

Structo 720

+SR

720

800

15

**

*

* Valid only upon request       ** Can be supplied

Surface finish

The ID surface roughness is maximum Ra 0,3 µm.

Delivery condition

Structo cylinder tubes are as standard delivered in cold drawn stress relieved annealed condition.

Warehousing

Roller burnished tubes are available in a wide range of sizes from OD 60-245 mm and ID 40-220 mm in Structo 525 steel grade.

Wear-resistant tubes

Structo’s cylinder tubes are used primarily for hydraulics in demanding environments, for example in the contracting, mining and construction industries.

 

Industrial hydraulics as well are exposed to major stresses. This makes the demands for reliability, wear-resistance and operating reliability even more important. For environmental reasons in particular, the fit be- tween hydraulic tubes and pistons must be precise.

Technique for smooth surfaces

Roller burnishing on the inside of tubes is a technique that provides very smooth services with high wear tolerance, which means that friction is minimised. This is a key factor for the life span of a hydraulic cylinder.
In contrast to honed cylinder tubes, Structo’s cylinder tubes have no running-in time.

 

The tube surfaces have the right bearing resistance when they are roller burnished, which reduces wear - and the risk that metal particles pollute the hydraulic oil and therefore damage pistons, pumps or valves.

Extra straight tubes

An equally important aspect is the straightness of the tubes. Structo hold a special position in this aspect as well.

 

The usual standard for straightness is 1:1000. Structo’s cylinder tubes have a guaranteed straightness of 1:2000, a barely measurable deviation that is hard to beat. And yet it is through repeated measurements that Structo’s cylinder tubes have obtained such a high, steady quality. The inner and outer diameters and any eccentricity of the tubes are also measured carefully.

More and more tubes are refined

A growing portion of Structo’s cylinder tubes are delivered after some kind of refinement - by agreement with the customer. This may be cold-forming or welding of features such as guiders and attachments.
All types of processing are performed before the roller burnishing, to guarantee the products’ surface finish and tolerances.

Our products

CDS-tubes

Structo have CDS tubes in stock in many standard dimensions and custom lengths and designs – for delivery at just the right time.

Details