Project Description
RT21
John Crane Type21 Replacement
Mechanical seal in the RT21 series is the ideal for general-purpose applications,designed for large batch production. Efficient stock keeping due to easily interchangeable parts.Type RT21 series is widely used in the Centrifugal pumps, turbine pumps, compressors, hot water pumps and other rotary shaft equipment.
Features
Single and ealstomer bellows mechanical seal
Bi-directional
Non-sliding design structure,elastomer bellows automatically compensates for primary ring wear.
Vailable in metric and inch sizes
RT21 series can also be used as double face mechanical seals in two sets arrangement
Recommended Applications
Water and waste water technology
Industrial pumps
Process pumps
Petroleum chemical industry
Other Rotating Equipment
Operating range
Shaft diameter: d1=8…80mm(0.375” …3.000”)
Pressure: p=0…1.0Mpa（145psi）
Temperature: t = -20 °C …150 °C(-4°F to 302°F)
Sliding velocity: Vg≤13m/s（42.6ft/m）
Product Structure
Combination Materials
1.Rotary Face
Carbon graphite resin impregnated Ak
Silicon carbide (RBSIC) O
Hot-Pressing Carbon Ac
2.Stationary Seat
Aluminium oxide(Ceramic) B
Silicon carbide (RBSIC) O
Tungsten carbide W1
3.Auxiliary Seal
Nitrile-Butadiene-Rubber (NBR) P
Fluorocarbon-Rubber (Viton) V
Ethylene-Propylene-Diene (EPDM) E
4.Spring
Stainless Steel (SUS304) F
5.Metal Parts
Stainless Steel (SUS304) F