Selection Of Packing Rings; Important; Differentiation Of Sealing Materials - Ecolab PDP II Notice Technique

6.

Selection of packing rings

NOTE
Properties and application areas for sealing materials FPM / EPDM:
Material
FPM
(Viton B)
EPDM

IMPORTANT

6.1

Differentiation of sealing materials

In our company we normally use different O rings colours to differentiate between FPM
(Viton B) and EPDM sealing materials:
FPM (Viton B) =
EPDM
Information as to which materials are used in the respective pump can be found in the pump
legend on the pump typeplate. The typeplate is located on the righthand side of the pump
head. An explanation of the pump legend can be found in Section
instructions.
Coloured rings are also fitted to the suction and delivery valves to identify the O ring material
in some pump types (See Figs. 6.1 or 6.2).
FPM (Viton B) = brown (standard)
Fig. 6.1
417101420_pneum_II.doc
The pneumatic metering pump in standard material combination (Pump head: PP,
suction/delivery valve: PP, valve balls: VA, O rings: FPM) is well suited to a wide range of
different chemical products, but cannot be used for all chemicals.
The chemical resistance of the O ring seals in particular is limited.
Depending on which chemicals are to be metered with the PDP, it may be necessary to
use a variant with EPDM O rings instead of the metering pump with standard O rings
(FPM).
Resistant to:
Slightly alkaline products
through to strong acids,
mineral oils, synthetic
hydraulic fluids, fuels,
numerous organic
solvents and chemicals
Diluted acids through to
highly alkaline chemicals
The above list can only provide a rough decision-making aid. No claim to reliability can
be derived therefrom.
Therefore, please always check the selection of suitable sealing materials with your
chemical manufacturer.
brown
= blue
Limited resistance or not
resistant to:
Highly alkaline chemicals (pH
values > 10)
Highly acidic chemicals
(pH values < 5)
EPDM = blue (optional)
Fig. 6.2
- 33 -
Normally used for:
Acidic cleaning agents,
wax, polish
Alkaline cleaning agents
13.1 of these operating
Rev. 4-07.10