DGS Tandem seal with intermediate labyrinth

A Primary seal gas supply
B Primary vent
C Secondary gas seal supply
S Secondary vent
D Separation gas supply

Item Description
1 Seal face, stationary
2 Seat, rotating
3 Thrust ring
4 Spring
5 Shaft sleeve and seat retainer
6 Intermediate sleeve
7, 8 Housing (size matched to installation space)
9 Separation seal (CSR)
10 Labyrinth
11 Intermediate labyrinth

Product links separation seals:
EagleBurgmann CSE
EagleBurgmann CSR
EagleBurgmann CobaSeal

DGS

Features

  • Gas-lubricated
  • Uni-directional or bi-directional
  • Ready-to-fit cartridge unit
  • Single, double, tandem and tandem with intermediate labyrinth available
  • Separation seals as labyrinths, carbon rings or CobaSeal are optionally available

Advantages

  • Wear-free and contact-free operation
  • Self-cleaning 3D gas grooves
  • High gas film stiffness
  • Secure cupped retainer for seat
  • Available in various materials for optimized chemical resistance
  • Proven, reliable and economical solution

Operating range

Shaft diameter:
ds1 = 29 ... 410 mm (1.14" ... 16.14")
Pressure:
p = 0 … 160 bar (2,320 PSI)
Design temperature:
t = -46 °C … +230 °C
(-51 °F ... +446 °F)
Sliding velocitiy:
vg = up to 227 m/s (744 ft/s)

Materials

Seal face: Silicon carbide with DLC coating, Carbon graphite
Seat: Silicon carbide with DLC coating
Secondary seals: FKM
Metal parts: 1.4006 or other stainless steels

Other materials on request.

Available also with EagleBurgmann DiamondFace technology.

Standards and approvals

  • NACE
  • API617

Notes

Compressor seals of the DGS series are based on a common technology and technical features, for instance O-Rings as secondary sealing elements. The different product variants are tailored to particular fields of application. The advantage over other products on the market is hidden in the detail. For example, the torque is transmitted to the rotating seat by friction forces only. And thus no holes and resulting weakening of the material are needed.

Dimensions on request.



Product variants

DGS20
Seals of the DGS20 series are the standard for medium pressures up to 120 bar (1,740 PSI). They have proven their suitability in thousands of applications worldwide. The seals are very rugged and are based on a mature design concept.

Operating range
Shaft diameter:
ds1 = 40 … 280 mm (1.57“… 11.02“)
Pressure: p = 20 … 120 bar (290 … 1,740 PSI)
Design temperature:
t = -46 °C … +230 °C
(-51 °F ... +446 °F)
Sliding velocity:
vg = up to 227 m/s (744 ft/s)

Materials
Seal face: Silicon carbide with DLC coating
Seat: Silicon carbide with DLC coating
Secondary seals: FKM or other elastomers depending on product gas composition
Metal parts: 1.4006 or other stainless steels
DGS21
Seals of the DGS21 series offer the lowest leakages of the elastomer-based DGS platform. They are therefore suitable for applications with high demands on low leakage. As some parts of the high-pressure PDGS series are used in the DGS21 series, the seal can be applied up to a pressure of 160 bar (2,320 PSI).

Operating range
Shaft diameter:
ds1 = 68 … 280 mm (2.68“… 11.02“)
Pressure:
p = 50 … 160 bar (725 … 2,320 PSI)
Design temperature:
t = -46 °C … +230 °C
(-51 °F ... +446 °F)
Sliding velocity: vg = up to 227 m/s (744 ft/s)

Materials
Seal face: Silicon carbide with DLC coating
Seat: Silicon carbide with DLC coating
Secondary seals: FKM or other elastomers depending on product gas composition
Metal parts: 1.4006 or other stainless steels
DGS25
The DGS25 gas seal series was developed for use in high-speed geared turbo compressors. Due to the special lightweight construction of the core parts and the extremely short working length design, the DGS25 covers the full spectrum of market requirements: Operation at extremely low pressures, robustness to machine vibrations and low impeller overhang. Dangerous stimulation of the core parts by omnipresent machine vibrations are prevented by their low mass or inertia. In addition, the overhang of the impeller from the bearing can be greatly reduced, thus decisively improving rotor dynamics. This enables mechanical run tests without pressure up to 227 m/s seal circumferential speed. No complex pressurization is necessary, open loop tests are child's play. In addition to the use in geared turbo compressors, the DGS25 can also be used in very short installation spaces. This is particularly often the case when compressors are upgraded from oil to gas seals to reduce emissions and operating costs and increase safety and availability.

Operating range
Shaft diameter:
d = 40 … 140 mm (1,57“… 5,51“)
Pressure:
p = up to 50 bar (… 725 PSI)
Design temperature:
t = -46 °C … +230 °C
(-51 °F … +446 °F)
Sliding velocity: vg = up to 227 m/s (744 ft/s)

Project specific special designs possible

Materials
Stationary seal face: Silicon carbide with DLC-coating, DiamondFace-coating optional
Rotating seal face (Seat): Silicon carbide with DLC-coating, DiamondFace-coating optional
Secondary seals: FKM or other elastomers, depending on product gas composition
Metal parts: 1.4006 or other stainless steels


Drawing items
1 Shortened stationary seal face
2 Shortened rotating seal face (seat)
3 Thick dynamic O-ring
l1K Shortened installation space

A Seal gas supply
B Vent
C Separation gas supply
DGS32
Due to the cost effective design, simple components and a hard/soft sliding material combination the DGS32 represents a reliable and economical solution for applications with partial contact of seal faces. This include, for example, slow-roll and turning operation (steam turbine driven compressors) or long and very frequent start/stop cycles.

Operating range
Shaft diameter:
ds1 = 30 … 400 mm (1.18"… 15.75")
Pressure: p = 0 … 120 bar (0 … 1,740 PSI)
Design temperature:
t = -46 °C … +230 °C
(-51 °F ... +446 °F)
Sliding velocity:
vg = 0 … 140 m/s (0 … 295 ft/s)

Materials
Seal face: Carbon graphite
Seat: Silicon carbide
Secondary seals: FKM or other elastomers depending on product gas composition
Metal parts: 1.4006 or other stainless steels