Innovation in detail: The new generation of elastomer bellows seals eMG1 and eMG

The eMG1 is 100 % compatible with the well-known MG1 standard seal. It has been innovated in detail and functionally expanded. The optimized geometry of the eMG1 elastomer bellows was tested in long-term applications on EagleBurgmann test facilities and in practical use. A vastly reduced outer diameter of the bellows support now allows direct support by a retaining ring or with the use of much smaller spacer rings. The optimized bellows shape improves the automatic alignment of the bellows on the shaft and minimizes stick-slip effects. The characteristic innovative element is the profiled PEEK-PTFE disk which ensures consistent centering across the entire pressure operating range, exhibits outstanding sliding properties and safeguards the automatic alignment of the elastomer bellows in operation through continuous self-cleaning. The eMG1 is available in numerous material combinations. The program now includes the new face material eSiC-Q7, a powerful silicon carbide optimized towards friction and wear with hydrodynamic properties.

The eMG is identical in construction with the eMG1, but has a 20 % shorter installation length. This provides manufacturers with new opportunities in pump construction: e.g., a more compact design due to shorter shafts with the associated material savings and increased efficiency. The rotating unit is extremely space-saving. The computed pre-modelled bellows design and the spring assembly have no excess lengths and the outer diameter of the bellows support was reduced to a minimum. The standard stationary seat of the eMG is also the short-installation type G6 ring. Synthetic resin impregnated carbon graphite) (B) and the optimized silicon carbide eSIC-Q7 are the standard materials.

Features of the eMG1 and eMG:

• for plain shafts, unbalanced, elastomer bellows rotating, bi-directional, can be used as single and double seal.

Advantages at a glance:

• 100 % compatible with MG1 (eMG1)
• 20 % shorter installation length (eMG)
• Smaller outer diameter of bellows support enables direct retaining ring support, or smaller spacer rings
• Optimal alignment characteristic through self-cleaning of disk/shaft
• Improved centering across entire pressure operating range
• Special bellows design protects the shaft across the entire seal length and the seal face during assembly
• Dimensional adjustments and additional stationary seat geometries possible

Operating range

• Shaft diameter: d1 = 15 … 100 mm (0.59" ... 3.94")
• Pressure: p1 = 16 bar (230 PSI), vacuum ... 0.5 bar (7.25 PSI), up to 1 bar (14.5 PSI) with seat locking
• Temperature: t = -20 °C … +140 °C (-4 °F … +284 °F)
• Sliding velocity: vg = 10 m/s (33 ft/s)
• Admissible axial movement: ±2.0 mm