Item Description
1, 9 Seal ring with bellows unit
2, 17 Mating ring
3, 10, 18, 21 Graphite ring
4 Clamp ring
5, 14, 16, 27 HSH Cap screw
6, 19 Gland plate
7 Gasket
11 Pumping ring
12, 25 Set screw
13, 15 Spring washer
20 Seal sleeve
22 Drive collar
23 Pin
24 Clamping sleeve
26, 29 Hexagon bolt
28 Setting device


LBO Liquid barrier OUT
LBI Liquid barrier IN

MBS682P-D

Features

  • API 682 Category 2 and 3, Type C, Arrangement 3 seal
  • Dual seal in back-to-back arrangement
  • Balanced
  • Cartridge unit
  • Rotating metal bellows
  • Shrink fitted seal rings and solid mating rings

Advantages

  • Compact design
  • Suited for applications with extreme high and low temperatures
  • Absence of dynamic O-Ring eleminates/reduces seal face hang-up
  • Bellows design minimizes variation in face load due to shaft expansion or face wear
  • Resistant to abrasive particles in the medium, no shaft or sleeve fretting
  • Also available in double ply design

Operating range

Shaft diameter: d1 = 20 ... 110 mm (0.79" ... 4.33")
Pressure single ply bellows: p = vacuum ... 25 bar (... 363 PSI)*
Pressure double ply bellows: p = vacuum ... 35 bar (... 508 PSI)
Temperature: t = -75 °C ... +400 °C (-103 °F ... +752 °F)
Sliding velocity: vg ... 23 m/s (... 75 ft/s)


* p >20 bar (290 PSI) on request.

Materials

Seal rings: Blister resistant carbon,
Silicon carbide SSiC (Q1), RBSiC (Q2)
Mating rings:
Silicon carbide SSiC (Q1), RBSiC (Q2)
Bellows: Inconel® 718 (M6)
Secondary seals: Graphite (G)
Metal parts: CrNiMo steel 316 (G),
Carpenter® 42 (T4)

Standards and approvals

  • API 682 / ISO 21049
  • API 682 4th ed. Cat. 2/3 - 3CW-BB



Product variants