Do not install, operate or maintain this product
without being fully trained and qualified in valve,
actuator and accessory installation, operation and
maintenance.
To avoid personal injury or property damage it is
important to carefully read, understand, and follow all
of the contents of this manual, including all safety
cautions and warnings.
If you have any questions about these instructions,
contact your Emerson sales office
before proceeding.
Installation
WARNING
Always wear protective gloves, clothing, and eyewear when performing any installation operations. Check with your
process or safety engineer for any other hazards that may be present from exposure to process media.
Personal injury or equipment damage caused by sudden release of pressure may result if the desuperheater is installed
where service conditions could exceed the limits given on the product nameplate. To avoid such injury or damage, provide
a relief valve for over‐pressure protection as required by government or accepted industry codes and good engineering
practices.
CAUTION
When ordered, the desuperheater configuration and construction materials were specified to meet particular pressure,
temperature, pressure drop, and fluid conditions. Do not apply any other conditions to the desuperheater without first
contacting your local Emerson sales office.
www.Fisher.com
Page 2
Yarway VenTemp Desuperheater
January 2019
Instruction Manual
D104420X012
Maintenance
WARNING
Avoid personal injury or property damage from sudden release of process pressure or bursting of parts. Before performing
any maintenance operations:
D Always wear protective gloves, clothing, and eyewear when performing any maintenance operations.
D Use bypass valves or completely shut off the process to isolate the valve from process pressure. Relieve process pressure
from both sides of the valve. Drain the process media from both sides of the valve.
D Use lock-out procedures to be sure the above measures stay in effect with you work on the equipment.
D Check with your process or safety engineer for any other hazards that may be present from exposure to process media.
CAUTION
When adjusting the travel stop for the closed position of the valve ball or disk, refer to the appropriate valve instruction
manual for detailed procedures. Undertravel or overtravel at the closed position may result in poor valve performance
and/or damage to the equipment.
Neither Emerson, Emerson Automation Solutions, nor any of their affiliated entities assumes responsibility for the selection, use or maintenance
of any product. Responsibility for proper selection, use, and maintenance of any product remains solely with the purchaser and end user.
Yarway and VenTemp are marks owned by one of the companies in the Emerson Automation Solutions business unit of Emerson Electric Co. Emerson
Automation Solutions, Emerson, and the Emerson logo are trademarks and service marks of Emerson Electric Co. All other marks are the property of their
respective owners.
The contents of this publication are presented for informational purposes only, and while every effort has been made to ensure their accuracy, they are not
to be construed as warranties or guarantees, express or implied, regarding the products or services described herein or their use or applicability. All sales are
governed by our terms and conditions, which are available upon request. We reserve the right to modify or improve the designs or specifications of such
products at any time without notice.
Emerson Automation Solutions
Marshalltown, Iowa 50158 USA
Sorocaba, 18087 Brazil
Cernay, 68700 France
Dubai, United Arab Emirates
Singapore 128461 Singapore
www.Fisher.com
2
E 2019 Fisher Controls International LLC. All rights reserved.
Page 3
YARWAY MODEL 25 VEN-TEMP DESUPERHEATER
InstallatIon and MaIntenance InstructIons
Before installation these instructions must be fully read and understood
UNPACKING
The Ven-Temp Desuperheater, Model 25, is
packed with the greatest of care in wooden
boxes or cartons for protection during handling
and transit to site. After hydrostatic testing,
the Ven-Temp Desuperheater is flushed
through with a high grade of preservative to
protect machined and internal surfaces from
corrosion. If it is found, however, that damage
has occurred during shipment, then this should
be reported immediately to your forwarder or
Yarway representative.
Particular care should be taken when removing
the Ven-Temp Desuperheater from its packing
and your special attention is required to check
carefully that no damage has occurred to
flange faces, threadings and butt weld profiles
(see figure 1).
INSTALLATION OF THE VEN-TEMP
DESUPERHEATER
Before installation, check the Ven-Temp
Desuperheater for any visible damage. Make
sure that protective covers are removed and
that butt weld ends and flange faces are
clean and without blemish. Any damage to
the unit should be reported immediately to
your forwarder or Yarway representative.
Checkthattheinformationonthe
documentation, identification plate and tag
number complies with the order specification.
Remove the Ven-Temp Desuperheater
carefully from its packaging, lifting by means
of straps around the body, or use the hoisting
lug if provided. Do not use the water inlet
connectionfor lifting.
The minimum pipe run, required downstream
of the Ven-Temp Desuperheater, varies with
each individual application and would be
specified by Yarway at the enquiry stage. This
straight run is needed to prevent erosion due
to impingement of water droplets against pipe
walls, valves and fittings. Upstream straight run
is normally 2 x D and the outlet straight run 4
meters, as a minimum. The distance from the
Ven-Temp Desuperheater to the temperature
sensor is nominally 12 - 15meters , although
the distance specific to the application would be
advised by Yarway at the enquiry stage. Longer
distances will ensure that full evaporation
of the water will take place at lower steam
velocities.
The temperature sensor should be located in
the upper half of the pipe, avoid branching of
the steam pipework between the Ven-Temp
Desuperheater and the sensor.
When installing the Ven-Temp Desuperheater
use gaskets and bolting material in accordance
with the relevant piping code, for example
ASME B31.1 or EN. Butt weld Ven-Temp
Desuperheaters should be welded inline using
proper weld procedures. Carefully check
the material compatibility of both body and
piping. In case of doubt consult Yarway. Post
weld heat treatment should be done with the
pipeline filled with an inert gas. Oxidation of
the vena contracta area may lead to significant
higher pressure drop over the Ven-Temp
Desuperheater than calculated. The unit
shall be installed with the water connection
vertically upwards. For an installation example,
seefigure 2.
Note: the Ven-Temp Desuperheaters should
befree of ‘forces, moments and torques’.
RECOMMENDATIONS
(acid cleaning of steamboilers)
Remove Ven-Temp Desuperheaters from
thepiping prior to acid cleaning!
Pipe bends should always be of the long radius
type to assist in keeping the water droplets in
suspension, until complete evaporation has
taken place. Installation may be in vertical or
horizontal piping, but the direction of water
injection should always be with the steam flow,
vertical downwards injection is not advised.
The steam flow direction is marked on the
Ven-Temp Desuperheater body by an arrow.
The position of the water inlet should
be12o’clock.
FIGURE 1
The water supply should be of a good quality,
clean and filtered for example boiler feed
water and should have a constant pressure as
specified in the order documents. Each water
supply line should be protected with its own
individual strainer (7) with a maximum element
perforation size of 0.1 mm.
As in the case of the steam pipework, use
gasketing and bolting in accordance with the
relevant piping code.
Flush out the water line before connecting to
the Ven-Temp Desuperheater mounting flange.
Check for damages
Retractable
injection nozzle
Check for damages
FIGURE 2
Water
789
Steam
•
Check for damages
•
Air
5
5
10
6
4
3
Air
Nameplate with
identification number
5
2
ItemDescription
1Temperature sensor
2Temperature transmitter
3Temperature controller
4Ven-Temp Desuperheater
5Air filter regulator
6 Water control valve
1
7Strainer
8Check valve
9Flange
10Pneumatic or E/P positioner
2
Page 5
YARWAY MODEL 25 VEN-TEMP DESUPERHEATER
InstallatIon and MaIntenance InstructIons
START-UP
Ensure that all components are installed
correctly. Connection of electrical supplies
and instrument air piping should be in
accordance with the manufacturer’s
instruction manual. Verify and adjust, if
necessary, set points for filter regulator(5)
and valve positioner (10), following the
manufacturer’s recommendations.
Similarly, calibrate the temperature
transmitter/controller (2) (3), verifying
automatic response to temperaturechanges.
Warm the steam main and open the valve in the
water supply. Check the water pressure at the
Ven-Temp Desuperheater. Verify the operation
of the temperature transmitter and controller
by manually increasing and decreasing the
output signal and observing indicated and
recorded temperatures.
When satisfactory coordination between
instrument signals and temperature is attained,
adjustment of the set point can be made and
the system transferred to automatic operation.
It is advisable to record the various steam
coordinates, over a sustained period, to verify
operation, adjusting where necessary.
MAINTENANCE
Note
Maintenance of the Ven-Temp Desuperheater
is straight forward and does not require any
special tools or training. Care should be taken
during any maintenance operation, particularly
when working with grinders, compressed
air and rotating machinery. It is imperative
that safety glasses and protective workwear
are used in accordance with standard safety
procedures. In case of doubt, consult your
supervisor or safety officer before commencing
any work on the equipment.
Injection nozzle
Injection nozzles may be retractable,
dependingon execution. Nozzles with holders
can be ordered as a complete spare part from
Yarway. Check your certified order drawing for
the nozzle type supplied.
Re-installation
When re-installing the Ven-Temp
Desuperheater make sure that the injection
nozzle opening points into the downward flow
direction!!! Use a high temperature nickel
compound on the flange bolting. Do not re-use
the graphite seals. Replace these seals when
overhauling the Ven-Temp Desuperheater.
SPARE PARTS
Make sure that the identification number
(indicated on the nameplate) is verified and
specified when ordering spare parts. For cross
sectional drawing and part list, see next page.
STORAGE PROCEDURE
Upon receipt, check both the Ven-Temp
Desuperheater and the packing case for any
transit damage. Any damage to the packing
container should be rectified to prevent the
ingress of dust or water, prior to placing the
equipment into storage.
Check the information contained on the
identification plate and documentation and
return the unit to its packing with protective
covers in place (see figure 1).
For short term storage, up to 6 months
duration, no additional preservation measures
are necessary. Retain the unit in its original
packing in a clean, dry indoor location.
If outdoor storage is unavoidable, then
the packing case should be enclosed in a
waterproof covering.
Removal
Before removing the Ven-Temp Desuperheater
from the system, ensure that both the
steam- and water pipework are pressureless
and vented. Isolate any electrical/pneumatic
supply to the actuator of the water valve, prior
to disconnection. Loosen steam flanges/butt
welds and water flange, but vent connections
before complete removal.
The Ven-Temp Desuperheater may now be
removed from the system. It is recommended
that the Ven-Temp Desuperheater is
transported to a convenient workshop which
has a workbench and vice. Lift the unit by
means of straps around the body, or use the
hoisting lug if provided.
For long term storage use only a dry indoor
location. Apply a cosmoline type grease to
machined faces. Retain in its original packing
and inspect at 3 monthly intervals to ensure
that no deterioration has occurred.
Note
Materials and data of units supplied, may
deviated from this Instruction Manual. Please
consult order documents in case of doubt.
CE marking depends on line size and will be
determined when ordered.
3
Page 6
YARWAY MODEL 25 VEN-TEMP DESUPERHEATER
InstallatIon and MaIntenance InstructIons
1
•
•
•
2
3
7
•
4
•
•
•
6
TABLE 1 - STANDARD MATERIALS
Carbon steelLow alloyHigh alloy
ItemName
1•Spray direction indicator
2•GasketSt.st./Graphite1. 4541/GraphiteSt.st./Graphite1.4541/GraphiteSt.st./Graphite1.4541/Graphite
Ven-Temp Desuperheaters are approved by authorizedauthorities to comply with the requirements of ASMEB31.1 Non-BEP or EN13445. All data subject to changes.