Standard Seal Range
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Seal Refurbishment Services
Elastomer Chemical Compatibility
Seal Face Chemical Compatibility
H21 is a DIN EN 12756–compliant mechanical seal for metric shafts, based on the industry standard "Type 21" design. It is widely used for its low cost / high efficiency ratio.
A rubber diaphragm is secured to the shaft with a drive band, which serves as both a secondary seal and positive torque element.
Mechanical compression on the spring-cap is typically delivered by a shoulder in the shaft / sleeve, threaded impeller or setting collar (available separately)
Temperature:
Pressure:
Speed:
-30°C to +200°C
< 10 bar, 145 psi, 1 MPa
< 13m/s, 2500 fpm
rpm < 780000/(3.14 x D1)
¹Guide-values only (due to diversity of possible applications). Enquire for specific-use cases. Maximum values of each parameter cannot be applied together.
PARTS
A
B
C
D
E
F
G
H
Stationary Cup
Stationary Face / Ring
Rotary Face / Ring
Rotary Retainer
Rotary Diaphragm
Rotary Drive Band
Spring
Spring Cap
SEAT OPTIONS
DCM
BO
BP
standard
o-ring, no slot
o-ring with slot
EQUIVALENT
T521
043-E
43 DIN
P03
Type 24
MG912/d1-G60
52
240 / P240
RB824
DATA SHEET
Rotary Face:
Stationary Face:
Elastomer:
Metal Parts:
CAB, SiC or TC
CER, SiC or TC
N, V or EP
304S.S.
H21DIN - Data Sheet
"Low-profile" Version:
H21T - Data Sheet
DIMENSIONS
Dimensions refer to installed length, not 'free' length:
*non-DIN EN 12756 size
refer H21T
T