Double Acting/Rotary

M74 and M75 are double acting seals for rotary rod and piston designs, rotary distributors for example.

Advantages Surface Roughness Operating Ranges
  • Excellent anti-friction characteristics
  • No stick-slip effect during start up
  • No adhesion effect
  • Can be used in dry and lubricated media
  • Single piece piston and cylinder head possible
  • Available up to 2000mm diamteter
  • Compact simple groove design
  • Cylinder/bore: Ra=0.05 - 0.4µm
  • Rod/shaft: Ra=0.05 - 0.4µm
  • GrooveØ: Ra<2.5µm
  • Groove walls: Ra<4µm
  • Up to 300 bar
  • Oscillatory up to 5m/s, intermittent.
    continuous up to 1m/s
  • Temperature from -60°C to 200° limited by the O-ring material
Table for Type M74
Type ROD DIA
C f8
Groove
DIA D H9

Groove

Width

L + 0.2

Diametral Clearance
Emax (BAR)
Radius O-Ring
        0 - 150 150 - 300   Series C/S
M74A 8 - 18.9 C + 4.9 2.2 0.4 - 0.25 0.25 - 0.15 0.3 - 0.5 000 1.78
M74B 19 - 37.9 C + 7.5 3.2 0.6 - 0.40 0.40 - 0.20 0.5 - 0.8 100 2.62
M74C 38 - 199.9 C + 11.0 4.2 0.6 - 0.40 0.40 - 0.20 0.8 - 1.2 200 3.53
M74D 200 - 255.9 C + 15.5 6.3 0.8 - 0.55 0.55 - 0.30 1.2 - 1.5 300 5.33
M74E 256 - 649.9 C + 21.0 8.1 0.8 - 0.55 0.55 - 0.30 1.5 - 2.0 400 7.00
M74F 650 - 999.9 C + 28.0 9.5 1.2 - 0.85 0.85 - 0.50 2.0 - 3.0 500 8.40
Table for Type M75
Type Cylinder
DIA A H9

 
Groove
DIA B H9

Groove

Width

L + 0.2

Diametral Clearance
Emax (BAR)
Radius O-Ring
        0 - 150 150 - 300   Series C/S
M75A 8 - 18.9 A - 4.9 2.2 0.4 - 0.25 0.25 - 0.15 0.3 - 0.5 000 1.78
M75B 19 - 37.9 A - 7.5 3.2 0.6 - 0.40 0.40 - 0.20 0.5 - 0.8 100 2.62
M75C 38 - 199.9 A - 11.0 4.2 0.6 - 0.40 0.40 - 0.20 0.8 - 1.2 200 3.53
M75D 200 - 255.9 A - 15.5 6.3 0.8 - 0.55 0.55 - 0.30 1.2 - 1.5 300 5.33
M75E 256 - 649.9 A - 21.0 8.1 0.8 - 0.55 0.55 - 0.30 1.5 - 2.0 400 7.00
M75F 650 - 999.9 A - 28.0 9.5 1.2 - 0.85 0.85 - 0.50 2.0 - 3.0 500 8.40

As a guide, the O-Ring ID for type M75 should be equal to or up to less than 5% of the goove Ø B.

Tel: 01623 751515 | Fax: 01623 753167 | Contact Us
Moontown Ltd