Material list for mechanical seals according to EN 12756.

Face materials

Identifier – EN 12756 Description
Synthetic carbons
A Carbon graphite, atimony impregnated
B Carbon graphite, resin impregnated, approved for foodstuffs
B3 Carbon graphite, resin impregnated
B5 Carbon, resin bonded
C Electrographite, antimony impregnated
Metals
E Cr-Steel
G CrNiMo-Steel
S Special cast CrMo steel
T41 1.4462 DLC-coated
Carbides | U = Tungsten carbides
U1 Tungsten carbide, Co-binder
U2 Tungsten carbide, Ni-binder
U22 Tungsten carbide, Ni-binder
U3 Tungsten carbide, NiCrMo-binder
U37 Tungsten carbide, NiCrMo-binder
U7 Tungsten carbide, binder-free
Q = Silicon carbides
Q1 SiC, sintered pressureless
Q12 SiC, sintered pressureless
Q2 SiC-Si, reaction bonded
Q22 SiC-Si, reaction bonded
Q3 SiC-C-Si, carbon silicon impregnated
Q32 SiC-C-Si, carbon silicon impregnated
Q6 SiC-C, SiC sintered pressureless with carbon
Q4 C-SiC, carbon surface silicated
Q19 SiC, DLC-coated
Q15 SiC, DiamondFaces
Metal oxides (Ceramics)
V Al-Oxide > 99%
V2 Al-Oxide > 96%
X Steatite (Magnesia silicate)
Plastics
Y1 PTFE, glassfibre reinforced
Y2 PTFE, carbon reinforced

Secondary seal components

Identifier – EN 12756 Description
Elastomers, not wrapped
B Butyl rubber (IIR)
E Ethylene propylene rubber (EPDM) e.g. Nordel
K Perfluorocarbon rubber (FFKM) e.g. Kalrez, Chemraz, Simriz
N Chloroprene rubber (CR) e.g. Neopren
P Nitrile-Butadiene-Rubber (NBR) e.g. Perbunan
S Silicone rubber (VMQ) e.g. Silopren
V Fluorocarbon rubber (FKM) e.g. Viton
X Hydrogenated Nitrile rubber(HNBR)
X Tetrafluoroethylene propylene rubber (FEPM) e.g. Aflas, Fluoranz
Elastomers, wrapped
M1 FKM, double PTFE-wrapped
M2 EPDM, double PTFE-wrapped
M3 VMQ, double PTFE-wrapped
M4 CR, double PTFE-wrapped
M5 FKM, FEP-wrapped
M7 FKM, double PTFE-wrapped/solid
Non-Elastomers
G Pure graphite
T PTFE (Polytetrafluoroethylene)
T2 PTFE, glass fiber reinforced
T3 PTFE, carbon reinforced
T12 PTFE, carbon-graphite reinforced
Y1 Plastic fiber/Aramid
Other Materials
U1 Perfluorocarbon rubber/PTFE

Spring and construction materials

Identifier – EN 12756 Description
Spring materials
G 1.4571 CrNiMo steel
M Hastelloy C-4 Nickel-base alloy
Construction materials
D C*steel
E Cr-steel
F CrNi-steel
F1 Special cast CrNi steel
G 1.4401 CrNiMo-Steel
G 1.4571 CrNiMo steel
G1 1.4462 CrNiMo steel – Duplex
G2 1.4439 CrNiMo steel
G3 NiCrMo steel
M = Nickel-base alloy
M Hastelloy C-4
M1 Hastelloy B-2
M3 Carpenter 20 Cb3
M4 Monel alloy K500
M5 Hastelloy C-276
M6 Inconel 718
T = Other materials
T1 CrNiMoCuNb steel
T2 Pure titanium
T3 Inconel 625
T4 Carpenter 42
T5 Incoloy 800