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Hydraulic Seals - Single Acting

Single Acting2 diagram

M72 and M73 are single acting, well proven rod and piston seals for working cylinders in hydraulics and pneumatics, and many applications in general engineering such as automotive and machine tools.

Like hydraulic seal piston seals, they offer a wide choice of sealing components.

Single Acting3 diagram

Advantages Surface Roughness Operating Ranges
  • Excellent anti-friction characteristics
  • No stick-slip effect during start up
  • No adhestion effect
  • Can be used in dry and lubricated media
  • Single piece piston and cylinder head poss.
  • Available up to 2000mm diameter
  • Compacy simple groove design
  • Cylinder/bore: Ra=0.05 - 0.6µm
  • Rod/shaft: Ra=0.05 - 0.5µm
  • GrooveØ: Ra<2.5µm
  • Groove walls: Ra<4µm
  • Reciprocating up to 800 bar and 15m/s
  • Temperature from -60°C + 200°C limited by the O=ring material
M72: ROD DIAMTER C f8/h9
HEAVY DUTY M72A STANDARD DUTY M72B LIGHT DUTY M72C GROOVE DIA D H9 GROOVE WIDTH L + 0.2 DIAMETRAL CLEARANCE EMAX (BAR) RADIUS R O-RING SERIES O-RING
0-200 200-400 C/S INSIDE Ø = C+
3 - 7.9 8 - 18.9 C+4.9 2.2 0.6 - 0.4 0.4 - 0.3 0.3 - 0.5 000 1.78 2.0
8 - 18.9 19 - 37.9 C + 7.3 3.2 0.8 - 0.5 0.5 - 0.3 0.5 - 0.8 100 2.62 3.5
8 - 18.9 19 - 37.9 38 - 199.9 C + 10.7 4.2 0.8 - 0.5 0.5 - 0.4 0.8 - 1.2 200 3.53 5.0
19 - 37.9 38 - 199.9 38 - 199.9 C + 15.1 6.3 1.0 - 0.6 0.6 - 0.4 1.2 - 1.5 300 5.33 7.0
38 - 199.9 200 - 255.9 200 - 255.9 C + 20.5 8.1 1.0 - 0.6 0.6 - 0.5 1.5 - 2.0 400 7.00 9.5
200 - 255.9 256 - 649.9 256 - 649.9 C + 24.0 8.1 1.2 - 1.0 1.0 - 0.6 1.5 - 2.0 400 7.00 13.0
256 - 649.9 650 - 999.9 C + 27.3 9.5 1.4 - 1.0 1.0 - 0.7 2.0 - 3.0 500 8.4 14.5
M73: BORE DIAMTER A H9
HEAVY DUTY M71A STANDARD DUTY M73B LIGHT DUTY M73C GROOVE DIA D H9 GROOVE WIDTH L + 0.2 DIAMETRAL CLEARANCE EMAX (BAR) RADIUS R O-RING
0-200 200-400 SERIES C/S
8 - 16.9 17 - 26.9 A - 4.9 2.2 0.6 - 0.4 0.4 - 0.3 0.3 - 0.5 000 1.78
17 - 26.9 27 - 59.9 A - 7.3 3.2 0.8 - 0.5 0.5 - 0.3 0.5 - 0.8 100 2.62
17 - 29.9 27 - 59.9 60 - 199.9 A - 10.7 4.2 0.8 - 0.5 0.5 - 0.4 0.8 - 1.2 200 3.53
27 - 59.9 60 - 199.9 200 - 255.9 A - 15.1 6.3 1.0 - 0.6 0.6 - 0.4 1.2 - 1.5 400 5.33
60 - 199.9 200 - 255.9 256 - 669.9 A - 20.5 8.1 1.0 - 0.6 0.6 - 0.4 1.5 - 2.0 400 7.00
200 - 255.9 256 - 669.9 670 - 999.9 A - 24.0 8.1 1.2 - 0.7 0.7 - 0.5 1.5 - 2.0 400 7.00
256 - 669.9 670 - 999.9 A - 27.3 9.5 1.4 - 0.8 0.8 - 0.6 2.0 - 3.0 500 8.4

As a guide, the O=Ring ID for type M73 should be equal to or up to less than 5% of the groove Ø B

Single Acting5 diagram

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