Item Description
1 Seal face
2 Stationary seat
3, 3a O-Ring
4 Spring

BT-RN

Features

  • Single pusher-type seal
  • Unbalanced
  • Conical spring
  • Dependent on direction of rotation

Advantages

The BT-RN represents the traditionally designed robust pusher seal. This type of mechanical seal is easy to install and covers a wide range of applications; its reliability has been proven by millions of units in worldwide operation. It is a convenient solution for the widest range of applications: for clean water as well as chemical media.

Operating range

Shaft diameter:
RN, RN3, RN6:
d1 = 6 … 110 mm (0.24" … 4.33"),
RN.NU, RN3.NU:
d1 = 10 … 100 mm (0.39" … 3.94"),
RN4: upon request
Pressure: p1* = 12 bar (174 PSI)
Temperature:
t* = -35 °C … +180 °C (-31 °F … +356 °F)
Sliding velocity: vg = 15 m/s (49 ft/s)

* Dependent on medium, size and material

Materials

Seal face:
CrNi steel (F, F1), CrNiMo steel (G), Tungsten carbide (U)
Seat:
Carbon graphite antimony impregnated (A), Carbon graphite resin impregnated (B), Tungsten carbide (U)
Elastomers:
NBR (P), EPDM (E), FKM (V), FFKM (K)
Metal parts: CrNi steel 1.4301 (F), CrNiMo steel 1.4401 (G)

Standards and approvals

  • KTW
  • W270
  • ACS
  • WRAS
  • NSF
  • FDA
  • DM 174/04

Notes

Seat ring of alternative seats can be supplied with short tail or with pin to block the seat and prevent seat rotation.



Product variants

BT-RN3

Product variant with seal faces made of brazed tungsten carbide which is suitable for media with medium corrosive and abrasive characteristics.

Item Description
1 Seal face housing
1a Brazed seal face
2 Stationary seat housing
2a Brazed stationary seat
3, 3a O-Ring
4 Spring
BT-RN4

Product variant with SiC seal face shrink-fitted into the seal face carrier.

Item Description
1 Seal face housing
1a Shrink fitted seal face
2 Stationary seat housing
2a Shrink fitted stationary seat
3, 3a O-Ring
4 Spring
BT-RN6

Product variant with PTFE secondary seal elements instead of elastomers. Mainly used in the chemical industry and for corrosive media.

Item Description
1 Seal face
2 Stationary seat
3 Wedge gasket (PTFE)
3a Gasket (PTFE)
4 Spring
5 Ring
BT-RN.NU / KU

Like the BT-RN/-RN3, but with dimensions in accordance with EN 12756.
BT-RN.NU has an installation length l1N and seat dimensions in accordance with EN 12756 (normal length).
BT-RN.KU has an installation length l1K and seat dimensions in accordance with EN 12756 (short length).

Item Description
1 Seal face
2 Stationary seat
3, 3a O-Ring
4 Spring
A Spacer (upon request)
True