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TI-SM-D01
Marketing release
Desuperheaters
&
Attemporators
PED Cert. No. 01 202 ZA/Q-02 0006
ISO 9001
ISO Cert. No. 01 100 045762
PRINCIPLES OF OPERATION
To reduce the temperature of steam in a pipe, water must be injected into the steam flow. To achieve good control, the water must be
atomised to form a fine spray that can be easily absorbed by the steam.
The result is an increased flow of steam at a lower temperature. Thus, by varying the amount of water added, the temperature of the steam
can be controlled.
For this closed heat system, the total heat energy remains constant, and so the enthalpy of the steam flow downstream must equal to the
sum of the enthalpy of the upstream steam and the spraywater being added.
Thus:
Qw = Qs * (h1-h3)
(h3-h2)
Where:Qw
Qs
h1
h2
h3
=
=
=
=
=
Quantity of water required in mass flow units
Flow of superheated steam in mass flow units
Specific enthalpy of superheated steam
Specific enthalpy of water
Specific enthalpy of the outflowing steam
MATERIALS OF CONSTRUCTION
Body
:
Flanges :
Nozzles :
316 Stainless Steel or A105 (Carbon Steel)
316 Stainless Steel or A105 (Carbon Steel)
316 Stainless Steel or 431 Stainless Steel Hardened
INSTALLATION RECOMMENDATIONS
All our Desuperheaters are designed to fit in a branch of the main steam line and thus installation of each unit is similar. The units can
be mounted into a main steam line of 100mm and larger. The unit should be installed into a T-piece, which is welded into the steam
line. A recommended minimum distance of 5 pipe diameters straight pipe, upstream of the unit (to prevent excessive turbulent flow), and
approximately 10 pipe diameters downstream - with a minimum of 2 meters - to ensure full absorption of the water being added.
The orientation of the unit must be such, that the nozzles point downstream, in the same direction as the steam flow. The unit can be installed
in a vertical or horizontal pipe, with the best installation being in a vertical installation with the flow upwards.
The temperature probe should be installed about 20 pipe diameters downstream of the unit - this depends on the type of desuperheater unit
used (see table below). The probe should be installed on the inside of the bend or on the top of the pipe.
Minimum installation distance required for desuperheater and temperature probes:
Pressure Reducing Valve and Desuperheater
Desuperheater and Temperature Probe
N/A
12 meters
Spillback
6 pipe diameters
10 meters
Steam Atomising
6 pipe diameters
8 meters
Conventional
Local regulations may restrict the use of this product to below the conditions quoted.
In the interests of development and improvement of the product, we reserve the right to change the specification without notice.
© Copyright 2006
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DETAIL A
DETAIL C
DETAIL B
Item
Description
Quantity
Material
1
Desuperheater Assembly
1
Carbon Steel or 316 Stainless Steel
2
D-S Gasket
1-10
Permanite Metallic Gasket
3
Steam Atomizing Nozzle
1-10
431 Stainless Steel, hardened to 30Rc
4
Nozzle Housing (Conventional)
1-10
316 Stainless Steel
5
Conventional Nozzle
1-10
316 Stainless Steel
6
Nozzle Housing (Spillback)
1-10
316 Stainless Steel
DESUPERHEATERS & ATTEMPORATORS
TI-SM-D01 Marketing release