description
profile ring-activated compact piston seal with integrated back-up rings. design for high pressure range, excellent static sealing capacity. mainly used in mining / tunnel- ing industry. external guiding elements required.
- asymmetric double-acting compact piston seal set, consisting of a gliding part, a preload element and backup elements.
- interference fit on the inside diameter.
- various materials are available for different purposes.
- easy to slip over stepped grooves (see notes on installation and recommended mounting space).
- highest degree of sealing across a wide temperature range.
- for pressures up to 1500 bar as a seal between pressurised spaces.
- excellent sealing in all pressure ranges.
- very good static sealing.
- suitable for short and long travel.
- due to compact design an inexpensive construction of piston is possible.
- no drag pressure build-up.
- for holding functions.
- improved guiding properties due to activated support elements.
- because of the excellent sealing effect,a fluid transport between the pressurised spaces is practically prevented.
- increased preload and reinforced guiding and support elements especially for high pressure application.
- 2 grooves on the inside diameter of the preload element for local limiting the preload force.
application
not bolded symbols; please consult our technical for application limitations
category of profile
machined only.
double acting
the PS 23-H seal is designed for use as a piston seal.
area of application: hydraulics
- reciprocating pistons in hydraulic cylinders.
- as piston seals for clamping function resp.for low requests for movement.
- as piston seal in high pressure cylinders (e.g.mining).
note
- very high frictional force.
- the ratio between nominal width and sealing height cs/H should be approximately 1/ 2.5 (essentially according to ISO 6547 housings
for piston seals with integrated guide rings).
- the guiding of the piston has to be assured by additional guiding elements.
function
PS 23-H profiles are compact piston seals designed to seal between two pressurised spaces; mainly for reciprocating movements. the design is based on application in standard hydraulic systems with conventional hydraulic oils. the operating parameters are as defined in the seal- ing data sheet and material data. requirements deviating from these parameters can be met to a certain degree by changing the geom- etry in the software program.
operating parameters & material
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.
1 pressure ratings are dependent on the size of the extrusion gap.
2 POM up to ø260 mm, PA above ø260 mm
++ … particularly suitable o … conditional suitable
+ … suitable – … not suitable
for detailed information regarding chemical resistance please refer to our „list of resistance“. for increased chemical and thermal resistance resp. for
higher gliding speeds PTFE-materials should be used (e.g. profile K09-F or a different sealing system).
note on special materials
other materials such as Viton, Silicone, EPDM, H-NBR, etc., can be used for the preload element, but they are only useful in specific cases (tem-
perature or chemical influences). the temperature limits are determined by the guide- and support parts, using special materials can expand the
temperature limits.
gap dimension
by using support parts, the extrusion gap for the sealing part is already integrated in the seal. the gap between piston and housing should not exceed 0,4 mm.
surface quality
| surface roughness |
Rtmax (μm) |
Ra (μm) |
| sliding surface | ≤2,5 | ≤0,05-0,3 |
| bottom of groove | ≤6,3 | ≤1,6 |
| groove face | ≤15 | ≤3 |
tolerance recommendation
| seal housing | tolerances |
| Ød | h9 |
| ØD | H9 |
mode of installation
first of all the preload element should be slipped over the piston and snapped into the groove, then the first backup element should be placed into the groove, followed by the gliding part and then the second backup element. the installation of the backup elements as well as the gliding part is generally trouble-free, at installation of the preload element the material deformation should not exceed the value of 30%, otherwise the permanent deformation would be too large.
recommended mounting space:
insertion chamfer:
in order to avoid damage to the piston seal during installation, the piston and the housing is to be chamfered and rounded as shown in the “recommended mounting space” drawing. the size of chamfer depends on the seal type and profile width.
| cs (mm) | c (mm) | |
| α = 15⁰ … 20⁰ | α = 20⁰ … 30⁰ | |
| 4 | 3.5 | 2 |
| 5 | 4 | 2.5 |
| 6 | 4.5 | 3 |
| 7.5 | 5 | 4 |
| 10 | 6 | 5 |
| 12.5 | 8.5 | 6.5 |
| 15 | 10 | 7.5 |
| 20 | 13 | 10 |
instead of a chamfer, the piston can also be designed with a radius. recommended size of the radius is equal to size of chamfer (R=c).
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 seal catalog…
the ratio between nominal width and seal height cs/H should not drop below 1/1,25. therefore we recommend the following housing heights.
| ØD [mm] | Ød [mm] | L [mm] | cs = (ØD – Ød)/2 [mm] |
| 5 ~ 24,9 | ØD – 8 | 6 | 4 |
| 25 ~ 49,9 | ØD – 10 | 7 | 5 |
| 50 ~ 74,9 | ØD – 12 | 8 | 6 |
| 75 ~ 149,9 | ØD – 16 | 10 | 7.5 |
| 150 ~ 299,9 | ØD – 20 | 12 | 10 |
| 300 ~ 500 | ØD – 24 | 18 | 12.5 |
| 500 ~ 750 | ØD – 30 | 20 | 15 |
| > 750 | ØD – 40 | 26 | 20 |
fitted:
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.