with groove on inside diameter, for piston application. split and non split design avail- able.

the guide ring type BWR 07 is mainly used on pistons. it provides guiding and bearing sur- faces between piston and cylinder tube and prevents metal to metal contact between them.

the BWR 07 consists of an extremely abrasion-resistant and low-friction POM-PTFE-Bronze compound and other materials. it can be used for hydraulic oil with a mineral oil base, for water-oil emulsions and for fire-resistant fluids as well as compressed air.

it has a U-shaped cross-section and is split with an angled butt joint. it can be easily expanded for fitting into corresponding installation grooves on the piston. the U- shaped groove arrangement secures the bearing against axial movement.


not bolded symbols; please consult our technical for application limitations

category of profile

machined product only.

operating parameters & material

material temperature max. surface speed max. specific load
 POM -50  … +100 4,0 m/s 25 N/mm2
PA -40  … +100 4,0 m/s 25 N/mm2
 PTFE glass -200  … +200 4,0 m/s 3 N/mm2
 PTFE bronze -200  … +200 5,0 m/s 4,5 N/mm2
Phenolic Resin -200  … +200 1,0 m/s 90 N/mm2

the stated operation conditions represent general indications. it is recommended not to use all maximum values simultaneously. surface speed limits apply only to the presence of adequate lubrication film.

2 POM up to ø260 mm, PA above ø260 mm

tolerance recommendation

seal housing tolerances
Ød h10
Ød1 h8

surface quality

surface roughness

Rtmax (μm)

Ra (μm)

sliding surface ≤1,5 0,3 – 0,5
bottom of groove ≤6,3 0.8
groove face ≤15 ≤3.2

fitting & installation

split bearing ring F07 to be snapped onto the piston.

seal & housing recommendations

please note that we are able to produce those profiles to your specific need or any non standard housing. for detail measurements, please see Jet seal pars catalog…

don’t hesitate to contact our technical department for further information or for special requirements (temperature, speed etc.), so that suitable materi- als and/or designs can be recommended.