Type：Double Mechanical Seal
Replacement：Burgmann M74D
Temperature：-20℃ to +180℃
Pressure：≤1.2Mpa
Speed：≤15m/s
Material：Q2,B,U2,P,E,V,F,G
Features
• For plain shafts
• Dual seal
• Unbalanced
• Rotating multiple springs
• Independent of direction of rotation
• Seal concept based on the M7 range
• Variant with pumping screw available (M74F- D)
Advantages
• Efficient stock keeping due to easily interchangeable
faces
• Extended selection of materials
• Flexibility in torque transmissions
• EN 12756 (for connection dimensions d1 up to
100 mm (3.94"))
Operating range
Shaft diameter: d1 = 18 … 200 mm (0.71" … 7.87")
Pressure: p1 = 25 bar (363 PSI)
Temperature: t = –50 °C … +220 °C
(–58 °F … +428 °F)
Sliding velocity: vg = 20 m/s (66 ft/s)
Axial movement:
d1 up to 100 mm: ±0.5 mm
d1 from 100 mm: ±2.0 mm
Materials
Seal face: Special cast CrMo steel (S),
Silicon carbide (Q1, Q2)
Seat G9: Carbon graphite antimony impregnated (A),
Carbon graphite resin impregnated (B),
Silicon carbide (Q1*, Q2*)
Seat G4: Silicon carbide (Q1*, Q2*)
Seat G6: Silicon carbide (Q1*, Q2*)
Seat G13: Carbon graphite antimony impregnated (A),
Carbon graphite resin impregnated (B)
* Cannot be combined with seal face in S
Standards and approvals
• EN 12756
Item Part no. to DIN 24250 Description
1.1 472.1 Seal face
1.2 472.2 Seal face
1.3 474 Thrust ring
1.4 485 Drive collar
1.5 477 Spring
1.6 904 Set screw
1.7 412.1 O-Ring
1.8 412.2 O-Ring
2 475.1 Seat (G9)
3 412.3 O-Ring
4 75.2 Seat (G9)
5 12.4 O-Ring
Recommended applications
• Process industry
• Chemical industry
• Pulp and paper industry
• Low solids content and low abrasive media
• Toxic and hazardous media
• Media with poor lubrication properties
• Adhesives
• Chemical standard pumps
