description

chevron sealing set, design with flexible sealing lips, good sealing ability in higher pressure range. for heavy industry hydraulics, water-hydraulic systems.

  • symmetric single-acting piston sealing set consisting mainly of one chevrons, combined with pressure ring and support ring to form a set.
  • various materials are available for different purposes.
  • good sealing in the higher pressure range.
  • for pressures up to 600 bar as a seal between pressurised spaces.
  • excellent static and dynamic sealing.
  • suitable for short and long travel.
  • very sturdy and wear-resistant.
  • insensitive to thermal damage caused by air in the oil.
  • open mounting space required (see mode of installation).
  • by varying the number of packings,friction as well as leakage behaviour can be influenced.
  • the pressure and the support ring can be split for easier installation, the chevron snaps in the groove uncut (see mode of installation).
  • mainly used for repair purposes.use more modern systems for new designs.
  • friction is less than with the K1012 type,but greater than with more modern sealing systems (e.g. K08). the mechanical efficiency of this packing is thus less than that of more state- of-the-art systems.
  • the central support prevents wedging of the individual packings under pressure. therefore the frictional forces in the high pressure range are relatively low.

application

not bolded symbols; please consult our technical for application limitations

category of profile

machined only.

single acting

the PS1315 seal is designed for use as a piston seal – either single or double acting where two seals are used ‘back to back’

area of application: hydraulics

  • reciprocating pistons in hydraulic cylinders; small swivelling motion also permissible. especially for heavy hydraulic applications or heavy-duty operating wear. conditions and in the case of tread.
  • used for sealing pistons and plungers of upstroke presses,where the return stroke is generated by it’s own weight.

note

  • expensive and complex design.
  • no adjustment possible.

function

PS1315 profiles are single-acting chevron seal sets designed to seal pressurised space against the atmosphere or – in case of back to back arrangement with intermediate guidering – 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

material temperature max. surface speed max. pressure 1 hydrolysis dry running wear resistance
sealing element spring
 PTFE 14.310 -200 °C … +260 °C 15 m/s 100 bar (10 MPa) ++ ++ +
PTFE  glass 14.310 -200 °C … +260 °C 15 m/s 160 bar (16 MPa) ++ ++ +
PTFE bronze 14.310 -200 °C … +260 °C 15 m/s 160 bar (16 MPa) ++ ++ +
 UHMWPE 14.310 -200 °C … +260 °C 15 m/s 200 bar (20 MPa) ++ + +

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 rubber

materials in other systems are to be preferred, attention  should be paid to restrictions for pressure range and wear resistance. for higher gliding  speeds another system should be used (e.g. PTFE materials).

gap dimension:

when using a pressure ring, the extrusion gap is already integrated  in the seal. the gap between piston and housing should not exceed cs·0.05.

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

open housings are required.

in case of already existing closed grooves  the pressure and the support ring can be split for installation  (pressure ring with cutting  gap 0). the

chevron has to be slipped in uncut. the support ring should be made of two parts (like ST08+K10) for easier installation into closed grooves.

recommended mounting space:

plastic guiderings (wearbands) have to feature a adequate cutting gap (recommendation:  2-5% of D). if metalic guides are used, spiral grooves shall be provided. in order to avoid drag pressure built up in case of back-to-back arrangement, the distance between the seals should be as small as possible.

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 seal-mart catalog…

the ratio between nominal width and seal height should be in accordance with following recommendations (see also manufacturing notes)

ØD [mm] L [mm] cs = (ØD – Ød)/2 [mm]
8 ~ 14,9 2,2 2.45
15 ~ 39,9 3.2 3.75
40 ~ 79,9 4.2 5.5
80 ~ 132,9 6.3 7.75
133 ~ 329,9 8.1 10.5
330 ~ 669,9 8.1 12.25
670 ~ 1000 9.5 14
> 1000 9.5 14

manufacturing notes

the following nominal widths are preferred. the theoretical packing height SH11 should be designed in accordance with the recommended values:

CS SH11
4 2.2
5 2.5
6 3
7.5 3.5
10 5
12.5 6
15 7.5
20 10
25 12.5
30 15

in order to be able to maintain the required height irrespective of the accumulated packing height ‘h’, the pressure ring is individually adjusted during the production of the V-packing set. to do so, a control dimension  is provided  by the NG40 software with a view to assisting this process.

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.