

With years of experience in linear axis manufacturing, we provide customer satisfaction through manufacturing and customization.
At Bos, we care about you and your company. We specialize in the customization, material selection, and manufacturing of Hydraulic Cylinder Barrels, and provide high-quality services according to your needs.




What distinguishes a premium Seamless Honed Barrel from conventional tubing is its exceptional combination of properties. The seamless manufacturing technique creates a homogeneous grain structure that provides superior mechanical strength, allowing for thinner wall designs without compromising pressure containment capabilities. This translates to weight savings while maintaining performance. The precision honing process achieves remarkably smooth internal surfaces with roughness values typically ranging from Ra 0.2μm to 0.8μm, significantly reducing friction and wear on seals and pistons . This surface finish is not just about smoothness—it facilitates optimal oil film maintenance, reduces operating temperatures, and extends the service life of the entire cylinder assembly.
The dimensional precision of these barrels is another critical advantage, with internal diameter tolerances achievable to H8, H9, or even H7 specifications depending on application requirements . This exacting precision ensures perfect piston alignment, eliminates uneven wear patterns, and prevents fluid bypass that can diminish cylinder efficiency. Additionally, these barrels exhibit exceptional straightness qualities, typically between 0.2-0.5mm per meter, which is crucial for proper cylinder assembly and operation without binding or excessive component wear.


Our manufacturing philosophy recognizes that not all applications are identical, which is why we offer a comprehensive range of Seamless Honed Barrel types to match specific operational requirements. Our standard cold-drawn honed barrels are ideal for general hydraulic applications, providing excellent precision and surface finish for most industrial uses. For more demanding applications, we offer stress-relieved (BKS) barrels that have undergone specialized heat treatment to minimize internal stresses, resulting in enhanced stability and reduced risk of deformation under fluctuating loads .
For the most challenging environments, we provide normalized (NBK) and quenched-tempered (Q+T) variants that offer superior mechanical properties and wear resistance . Our specialized skived and roller burnished (SRB) barrels deliver the highest level of surface finish (≤0.4μm Ra) and dimensional accuracy, making them the preferred choice for high-speed hydraulic applications and precision equipment .
Our technical capabilities enable us to produce Seamless Honed Barrels in an extensive range of sizes, with internal diameters typically available from 30mm to 400mm, and even up to 1000mm for specialized deep-hole boring applications . Wall thickness can be precisely controlled according to design parameters, with standard tolerances of ±7.5% to ±10% depending on diameter . We work with various steel grades including 20#, 45#, ST52, SAE1020, SAE1045, and alloy steels such as 27SiMn and 42CrMo, each selected for their specific performance characteristics in different operating environments .

Bore diameter depends on required force (F = P × A). Wall thickness is selected based on design pressure, safety factor, and buckling/deflection requirements. Follow manufacturer or engineering standards (e.g., ISO, DIN).