Issued: 10/11
Supersedes: 8/10
Corrosion Resistant Pumps
Flygt corrosion resistant pumps are constructed of stainless steel for corrosive liquid or salt water
applications where cast iron is not recommended. Stainless steel pumps are corrosion resistant.
2000 Series Stainless Steel Pumps:
Model 2730 is available in type DS and is constructed in 316 stainless steel.
Model 2740 is available in types BS and DS and is constructed in 316 stainless steel.
Model 2750 is available in type BS and is constructed in 316 stainless steel.
3000 Series Stainless Steel Pump:
Model 3060 is available in types CP, CS, CT, DP, DS and DT and constructed in 316 stainless steel.
8000 Series Stainless Steel Pumps:
The following pumps are constructed entirely in stainless steel:
Models 8050, 8053, 8056 and 8058 are available in types DP and DS and are constructed in 316
stainless steel.
Issued: 11/08
Supersedes: 12/99
Corrosion Resistant Materials
(for 3000 series pumps)
3000 series corrosion resistant pumps:
Selective addition of parts in corrosion resistant
materials offers an economical modular system for the
solution of corrosive pumping problems.
Selecting a pump for demanding applications
requires that every parameter of the liquid - pH value,
temperature, solids content and type, viscosity, etc. - is
taken into consideration. With proper information, Flygt
can offer a solution that optimizes both the technical
and economical aspects.
An increasing number of industrial users are now
specifying submersible pumps instead of the
cumbersome conventional pumps installed in separate
dry and wet pits with vertical long shafts. The main
reason is that submersible pumps offer a choice of
special materials either for the entire pump or selectively
for certain parts only.
Flygt’s “modular” material selection system makes it
especially easy for the customer to adapt the pump
simply and economically to specific requirements.
The pump can be gradually upgraded to meet
increasingly demanding application requirements
without becoming overspecified and unnecessarily
costly.
The charts and illustrations that follow show how the
overall corrosion resistance of the cast iron Flygt pump
can be upgraded until it achieves the right combination
best suited and most economical for the intended
application. Any such combination can be ordered
fully assembled but an existing standard pump can
also be modified by ordering the necessary special
parts.
For instance, a standard cast iron pump can be fitted
with a stainless steel impeller for applications where
the liquid itself is non-aggressive and clean but the
combination of high oxygen content and high flow
velocity may give rise to accelerated corrosion.
If, on the other hand, the pH of the liquid varies
continuously within a broad interval (pH 4 to 14) and
abrasive particles are also present, the entire hydraulic
end (volute, oil housing bottom and impeller) should
be supplied in stainless steel and the pump fitted with
a special shaft seal. In this case, the motor section may
still remain cast iron for cost saving.
A pump made entirely of stainless steel, including a
stainless steel cable protector, should always be used
for highly aggressive liquids, e.g. with pH constantly
below 6, especially if the application involves elevated
temperatures and abrasive particles.
While considering special materials, remember that
the original standard versions made of cast iron are
also reliable and economical when used in sea water.
Ensure, however, that the pump is epoxy coated and
provided with zinc anodes for cathodic protection
against galvanic corrosion by contacting your nearest
Flygt products distributor.
Under normal conditions and in most models, the
motor is cooled by a portion of the liquid being diverted
through a cooling jacket surrounding the stator. Due
to this arrangement, Flygt submersible pumps are
also suitable for continuous dry installations and are
inherently floodproof.
However, if the pump can be expected to draw air
frequently, the internal cooling jacket can be sealed
off from the volute and an independent cooling system
added by feeding water from an external source. Such
an arrangement can also be used when pumping liquids
at elevated temperatures.
Issued:
5/89
Corrosion Resistant Pump Combinations
(for 3000 series pumps)
3000 series corrosion resistant pumps:
Stainless Steel Impeller:
Here the original standard cast iron
pump is equipped with a stainless
steel impeller for applications such
as the handling of water which
is basically clean but has a high
oxygen content and flows at a high
velocity.
Stainless Steel Pump
with Cooling Jacket:
The entire pump is made of
stainless steel and is equipped
with a cooling jacket.
This pump is intended for
applications in which the liquid
is highly aggressive, i.e. when
pH is constantly below 6,
especially in connection with
abrasive particles. Part of the
liquid being pumped circulates
through the cooling jacket
around the stator housing, in
order to cool the motor.
Entire Hydraulic End made
of Stainless Steel:
All hydraulic end components, ie.
the volute, oil housing bottom and
impeller, are made of stainless
steel and the pump is equipped
with a special mechanical shaft
seal assembly for corrosive liquids.
Suitable for applications in which the
pH of the liquid varies continuously
within a broad interval (4 - 14) and
the liquid contains abrasive particles.
Stainless Steel Pump with
Separate External Cooling
System:
Same design as in the preceding
example, although the cooling
system is isolated from the volute
and connected to an external water
supply. This solution is preferable
if a highly aggressive liquid also
contains fairly large particles or
fibers that could be deposited on
the inside of the cooling jacket.
The same applies if the pump often
draws air and there is a risk of
running dry or if the liquid pumped
is at elevated temperatures. For
liquids containing fine abrasive
particles, the design
allows the external
cooling liquid to be used
for continuously flushing
the shaft seal.
Supersedes:
Issued: 8/10
Supersedes: 11/08
Corrosion Resistant Pumps
(for 8000 series pumps)
Components in
Stainless Steel
Motor Housing
8000 series
models available:
D 8050
D 8053
D 8056
D 8058
Seal Housing
Impeller
Volute
D 8000 series pumps are available in types DP and DS and constructed in 316 stainless steel.
D 8000 series pumps are designed to work in demanding environments where you need to handle
corrosive liquids and sludge, as well as large solids.
Major pump components, such as motor housing, seal housing, volute and impeller are made of AISI
type 316 stainless steel with smooth surfaces devoid of blow holes or other irregularities. All exposed
nuts and bolts are AISI 316 stainless steel.
The recessed impeller is capable of handling solids, fibrous materials, heavy sludge and other matter
found in wastewater. The impeller is keyed to the shaft.
Issued: 5/89
Supersedes:
Corrosion Resistance Limitations
This chart indicates how some chemicals affect the parts of the
pump. Information concerning the effect of other chemicals is
available from your nearest source of Flygt products.
Values are based on 40°C (104°F)
PARTS AND MATERIALS EXPOSED
Seal Unit
Outer Face
Aluminum Oxide
Silicon Carbide
1
1
1
3
3
3
3
3
3
3
3
1
1
1
1
1
1
1
1
1
1
2
1
1
1
3
3
3
1
1
2
2
3
2
2
3
1
2
2
1
1
1
1
2
1
1
3
3
3
2
1
1
2
2
1
1
1
3
3
3
2
3
3
3
3
2
1
1
3
1
1
1
1
1
1
1
1
3
3
3
3
3
3
3
3
3
3
3
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
5
5
5
1
1
1
1
1
1
1
1
1-2
1
1
1
1
1
1
1
1
1
1
1
2
1
1
1
1
1
1
1
1
1
2
2
2
5
0.5-50
10
2
3
2-3
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
2
1
1
2
3
2-3
3
3
3
1
1
1
1
1
1
50
100
100
100
100
1
1
1
1
1
3
3
2
3
2
3
3
1
1
1
3
3
2
3
2
3
3
3
3
3
1
2
3
3
3
2
2
2
3
2
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
Silicone Rubber
1
1
3
1
1
1
1
1
1
1
1
Hypalon
Tungsten Carbide
SS, AISI 316 (Cable Protector)
Ethylenepropylene
Rubber
Chloroprene Rubber
Motor Cable
10
5
ALL
1
20
5
10
5
10
5
ALL
*%
Nitrile Rubber
Chemical
FORMULA
SS, AISI 316, 329
Substance
O-rings
Fluorinated Rubber
Pump
CORROSION RESISTANCE RATING
ACIDS
ACETIC ACID
ACETIC ACID
BENZOIC ACID
HYDROCHLORIC ACID
NITRIC ACID
NITRIC ACID
PHOSPHORIC ACID
PHOSPHORIC ACID
SULPHURIC ACID
SULPHURIC ACID
TANNIC ACID
CH3COOH
CH3COOH
C6H5COOH
HCL
HNO3
HNO3
H3PO4
H3PO4
H2SO4
H2SO4
C14H10O9
ALKALIES
AMMONIUM HYDROXIDE
CALCIUM HYDROXIDE
SODIUM HYDROXIDE
NH4OH
Ca(OH)2
NaOH
SALTS
ALUMINUM CHLORIDE
FERRIC CHLORIDE
FERROUS CHLORIDE
ALCL3
FeCL3
FeCL2
ORGANIC SUBSTANCES
AND SOLVENTS
ACETON
ETYLACETATE
MINERAL OIL
TOLUENE
VEGETABLE OIL
CH3COCH3
CH3CO2C2H5
-C7H8
--
* Concentration by Weight
SS = stainless steel
KEY:
1 = GOOD
2 = FAIR
3 = POOR
Issued: 10/11
Supersedes: 8/10
Corrosion Resistant Materials based on pH
Special Materials and their Application Range Based on pH
pH
Aluminum _ _ _ _ _ _ _ _ _ _ _
__
Cast Steel
Cast Iron _ _ _ _ _ _ _ _ _ _
_____
_Stainless
_ _ _ _ _Steel
__________
0
1
2
3
4
Increasingly Acidic
5
6
<
7
•
8
9
10
11
12
Neutral
3060
2720
CP
CS
CT
DP
DS
DT
•
•
•
•
•
•
•
•
•
2730
2740
2750
8050
8053
8056
8058
•
•
•
•
•
•
pH
>
Models Constructed
Entirely In Stainless Steel
BS
14
Increasingly Alkaline
Pump Models Available
Model
13
•
•
•
•