Type 25E Electric Pilot Operated Valve

Type 25E Electric Pilot Operated Valve
INSTALLATION AND MAINTENANCE INSTRUCTIONS
IM-1-1119-US
October 2015
Type 25E Electric Pilot Operated Valve
(for Steam or Air Service)
Safety Information
1.6 The system
Safe operation of these products can only be guaranteed if
they are properly installed, commissioned, used and maintained
by qualified personnel (see Section 1.11) in compliance with
the operating instructions. General installation and safety
instructions for pipeline and plant construction, as well as the
proper use of tools and safety equipment must also be complied
with.
Consider the effect on the complete system of the work
proposed. Will any proposed action (e.g. closing isolation
valves, electrical isolation) put any other part of the system or
any personnel at risk?
Dangers might include isolation of vents or protective devices
or the rendering ineffective of controls or alarms. Ensure
isolation valves are turned on and off in a gradual way to avoid
system shocks.
1.1 Intended use
Referring to the Installation and Maintenance Instructions,
name-plate and Technical Information Sheet, check that the
product is suitable for the intended use / application.
1.7 Pressure systems
Ensure that any pressure is isolated and safely vented to
atmospheric pressure. Consider double isolation (double block
and bleed) and the locking or labelling of closed valves. Do not
assume that the system has depressurised even when the
pressure gauge indicates zero.
i) The products have been specifically designed for use on
steam, air or water/condensate. The products’ use on other
fluids may be possible but, if this is contemplated, Spirax
Sarco should be contacted to confirm the suitability of the
product for the application being considered.
1.8 Temperature
Allow time for temperature to normalise after isolation to avoid
danger of burns.
ii) Check material suitability, pressure and temperature and
their maximum and minimum values. If the maximum
operating limits of the product are lower than those of the
system in which it is being fitted, or if malfunction of the
product could result in a dangerous overpressure or
overtemperature occurrence, ensure a safety device is
included in the system to prevent such over-limit situations.
1.9 Tools and consumables
Before starting work ensure that you have suitable tools and / or
consumables available. Use only genuine Spirax Sarco
replacement parts.
1.10 Protective clothing
iii) Determine the correct installation situation and direction
of fluid flow.
Consider whether you and / or others in the vicinity require any
protective clothing to protect against the hazards of, for example,
chemicals, high / low temperature, radiation, noise, falling
objects, and dangers to eyes and face.
iv) Spirax Sarco products are not intended to withstand external
stresses that may be induced by any system to which they
are fitted. It is the responsibility of the installer to consider
these stresses and take adequate precautions to minimise
them.
1.11 Permits to work
All work must be carried out or be supervised by a suitably
competent person. Installation and operating personnel should
be trained in the correct use of the product according to the
Installation and Maintenance Instructions.
v) Remove protection covers from all connections and
protective film from all name-plates, where appropriate,
before installation on steam or other high temperature
applications.
Where a formal ‘permit to work’ system is in force it must be
complied with. Where there is no such system, it is recommended
that a responsible person should know what work is going on
and, where necessary, arrange to have an assistant whose
primary responsibility is safety.
1.2 Access
Ensure safe access and if necessary a safe working platform
(suitably guarded) before attempting to work on the product.
Arrange suitable lifting gear if required.
Post ‘warning notices’ if necessary.
1.3 Lighting
1.12 Handling
Ensure adequate lighting, particularly where detailed or intricate
work is required.
Manual handling of large and/or heavy products may present
a risk of injury. Lifting, pushing, pulling, carrying or supporting
a load by bodily force can cause injury particularly to the back.
You are advised to assess the risks taking into account the
task, the individual, the load and the working environment and
use the appropriate handling method depending on the
circumstances of the work being done.
1.4 Hazardous liquids or gases in the pipeline
Consider what is in the pipeline or what may have been in the
pipeline at some previous time. Consider: flammable materials,
substances hazardous to health, extremes of temperature.
1.5 Hazardous environment around the product
Consider: explosion risk areas, lack of oxygen (e.g. tanks, pits),
dangerous gases, extremes of temperature, hot surfaces, fire
hazard (e.g. during welding), excessive noise, moving
machinery.
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1.13 Residual hazards
Steam Mains - Do's and Dont's:
In normal use the external surface of the product
may be very hot. If used at the maximum
permitted operating conditions the surface
temperature of some products may reach
temperatures in excess of 300°C (572°F).
4
7
4
7
4
7
4
7
4
7
Many products are not self-draining. Take due
care when dismantling or removing the product
from an installation (refer to 'Maintenance
instructions').
1.14 Freezing
Provision must be made to protect products
which are not self-draining against frost
damage in environments where they may be
exposed to temperatures below freezing point.
Steam
1.15 Disposal
Unless otherwise stated in the Installation
and Maintenance Instructions, this product
is recyclable and no ecological hazard is
anticipated with its disposal providing due
care is taken.
1.16 Returning products
Customers and stockists are reminded that
under EC Health, Safety and Environment Law,
when returning products to Spirax Sarco they
must provide information on any hazards and
the precautions to be taken due to contamination
residues or mechanical damage which may
present a health, safety or environmental risk.
This information must be provided in writing
including Health and Safety data sheets relating
to any substances identified as hazardous or
potentially hazardous.
1.17 Working safely with cast iron
products on steam
Cast iron products are commonly found on
steam and condensate systems. If installed
correctly using good steam engineering
practices, it is perfectly safe. However, because
of its mechanical properties, it is less forgiving
compared to other materials such as SG iron or
carbon steel. The following are the good
engineering practices required to prevent
waterhammer and ensure safe working
conditions on a steam system.
Prevention of tensile stressing
Pipe misalignment:
Installing products or re-assembling after maintenance:
1
Safe Handling
Cast Iron is a brittle
material. If the product
is dropped during
installation and there
is any risk of damage
the product should
not be used unless it
is fully inspected and
pressure tested by the
manufacturer.
4
7
Do not over tighten.
Use correct torque figures.
Prevention of water hammer
Steam trapping on steam mains:
30 - 50 metre intervals
Gradient
Steam
1:100
Trap set
Condensate
Gradient
1:100
Trap set
Condensate
Steam
Trap set
Condensate
2
7
3
2
1
3
5
6
4
2
8
Flange bolts should be gradually tightened across
diameters to ensure even load and alignment.
Thermal expansion:
Guides
Limit rods
Guides
Medium
distance
Axial movement
Short
distance
Small
lateral
movement
Large
lateral
movement
Fixing point
Fixing point
Limit rods
Axial movement
Guides
Large
lateral
movement
Small
lateral
movement
Guides
REMOTE
MANUAL SWITCH,
PROGRAM CLOCK,
TEMPERATURE SWITCH
OR PRESSURE SWITCH
ELECTRIC
POWER
Steam
Supply
STEAM TO
PROCESS
Spirax Sarco
1/2” TD-52L Trap
Spirax Sarco
Strainer
Spirax Sarco 25E
Electric Pilot
Operated Valve
Spirax Sarco
Strainer
Fig 1 Automatic Control Valve Electrically Operated from Remote Station or Stations
Room
Thermostat
Steam
Supply
Spirax Sarco
Strainer
Spirax Sarco
1/2” TD-52L Trap
Spirax Sarco
1/2” TD-52L Trap
Fin-Tube
Radiation
Spirax Sarco 25E
Electric Control Valve
Spirax Sarco
Strainer
Condensate Return Line
Fig 2 Controlling Temperature of Greenhouse or Other Similar Buildings
3
Cap Nut
1A
1D
E
N
J
1E
1F
1G
1H
1C
H
G
Fig 3
Sizes 1/2” - 2”
INSTALLING THE VALVE
IMPORTANT: Step by step instructions on the following
pages should be read carefully before installing the valve.
Bypass
Unpack Carefully
Do not lift the regulator by the electric pilot. Grasp the body of
the valve firmly when lifting.
Piping
1. Typical hookup sketches as shown in Figs. 1 and 2 will aid in
planning a correct installation.
2. Before installing the valve make sure the piping is free of
foreign material, scale, etc.
3.Make certain the arrow cast on regular valve body is pointing
in the direction of flow. 4. Regulating valve should always be installed in a horizontal
line. (See Figs. 1 and 2)
4
1.A bypass connection, as shown in Figs. 1 and 2, is recommended so that the valve can be serviced without shutting
down the equipment.
2.The bypass valve should be the same size as the regulating valve.
Steam Line Drain Trap
To insure proper operation of the valve and avoid premature
wear, it is recommended that on steam applications a steam
trap be installed on the same supply line. (See Figs. 1 and 2)
Pipeline Strainers
1.It is strongly recommended that strainers be installed
before the regulating valve and steam traps. (Figs.1 and 2)
2.Make certain adequate clearance is provided for screen
removal and blowdown connection between strainer and
regulating valve body.
Cap Nut
1D
J
1A
E
E
1F
1F
1G
1H
1G
1C
G
H
1H
G
H
1C
Fig 4
Sizes 2-1/2” - 4”
Fig 7
6” Size
Stop Valves
HOW IT WORKS
Normally, the main valve and electric pilot valve are closed.
When the electric pilot is energized, pilot valve will open allowing
steam or air to pressurize main valve diaphragm chamber which
opens main valve fully. When electric pilot is de-energized,
pilot valve closes and diaphragm chamber pressure is relieved
through control orifice. Main valve will close tight by the force
of head spring and steam or air pressure acting on valve head.
All stop valves on the supply side, as well as on the
downstream side of the regulating valve, should be of the
gate type so as to insure full rated capacity and good
control.
Wiring
1. Check name plate on electric pilot for correct voltage
and service conditions.
2.Wiring must comply with local and national electrical codes.
3.Solenoid enclosure is provided with hole to accommodate standard 1/2 inch conduit connection.
4.The solenoid enclosure can be rotated to facilitate
wiring by loosening the cap nut (See Fig. 6).
Electical Signal
Electic
Pilot
Solenoid
Orifice
Main Valve
Inlet
Control
Pressure
Main
Diaphragm
5
Type 25E Electric On-Off Regulator
MAINTENANCE
General Inspection
While a program of planned maintenance is always to be
recommended, the 25E Regulator will give long and trouble-free
service is correctly selected, installed and kept reasonably free
of dirt and foreign matter. Dirt and foreign matter are most likely
to collect during installation and later trouble can be avoided by
inspecting the installation a few days later. Check the following:
Refer Fig. No. 3, 4, and 7.
1. Clean all pipeline strainers (remove screens to clean).
2. Check the main valve seat and protective screen (1D).
3. Inspect and clean orifices (E) and (H).
4. Check all joints for leakage.
Electric Pilot, Inspection of Solenoid and Internal Parts
(Refer to Fig.6)
1. Shut off steam supply to valve and turn off electrical power.
2. Unscrew solenoid housing nut and remove housing, coil,
and housing base plate.
3.Base assembly (4J) is now accessible for removal with
hexagon or adjustable open end wrench.
4.Valve head, spring ad seat are now accessible for
inspection, cleaning and replacement, if necessary. When
replacing seat use compound on threads (remove excess).
Tighten to 75 in.-lb. torque.
Valve Sizes 1/2” thru 4”.
Inspecting and Replacing Main Valve Head and Seat
(Refer to Figs. 3 and 4)
1. Unscrew copper tubing connection at (J) and (N).
2. Remove main valve cover cap screws (1A).
3. Remove main valve cover, strainer, screen, and head
spring.
4. Head can then be removed by simply withdrawing with
pliers or similar tool.
5. Inspection should then be made to determine if scale or
other foreign material prevented tight closure of the head
and seat.
6. If the head or seat shows signs of wear this can be corrected by grinding, using a fine grinding compound (400
grit) providing the wear is not severe. Check for body
erosion.
7. If it is necessary to replace the valve seat, this can be
removed from the valve body using a standard hexagon
socket. (Valve sizes 1/2” to 2”). When replacing the valve
seat, a new gasket should be used to insure a tight joint.
2-1/2” thru 6” valves contain raised lugs for removal and
seal metal-to-metal without a gasket. Replacment heads
and seats should be lapped in.
5
4-H
Cap Nut
F
4-J
4
4-K
Fig 6
6
B
D
4-G
E
A
Valves Sizes 1/2” thru 4”
Inspecting and Replacing Main Valve Diaphragms (Refer
to Figs. 3 and 4)
1. Unscrew copper tubing connection at (G).
2. Remove main valve diaphragm bolts (1C).
3. This will allow the lower diaphragm case to be
removed.
4.The 2 metal diaphragms (1H) should be inspected to insure
that they have not become distorted or possibly fractured
as a result of abnormal operating conditions.
5.At the same time any accumulation of dirt or foreign material should be removed from the diaphragm case.
6.The valve stem (1F) should also be checked to make sure
it is free to move and that there is no scale or foreign material lodged in the guide bushing.
7.Before reassembling diaphragms in 1/2” thru 4” sizes,
main valve head must be in place and held in a closed
posiiton with the return spring and main valve cover.
8.Make certain pressure plate (1G) is set properly.
(Refer to Figure 5)
9.Care should be taken in centering the diaphragms properly
and equalizing bolt take-up uniformly.
Servicing the Main Valve Head and Seat.
5.Loosen the diaphragm plate set screw and remove the
diaphragm plate (1G).
6. Remove the top cover bolts (1A). and cover.
7.Remove the stem and head assembly from the valve.
Inspect the head and seat for wear.
8.Check for body erosion around the seat ring.
9.Replacement seats and heads should be lapped in,
and minor wear can also be corrected by lapping with
400 grit compound.
10. On re-assembly be sure diaphragm plate (1G) is set
at 27/64” and set screw securely tightened.
Spare Parts Kits
Spare parts kits and coils are available. Refer to
TIS 3.027 for 1/2” to 4” Main Valve
TIS 3.029 for 6” Main Valve
TIS 3.0271 for Pilot Valves
6” VALVE ONLY.
Inspecting and Replacing Main Valve Diaphragms, Seat,
and Head Assembly (Refer to Figure 7)
Diaphragms
1.Unscrew copper tubing connections (G) to lower diaphragm chamber.
2.Remove main valve diaphragm bolts (1C) and drop lower
diaphragm case.
3.The 2 metal diaphragms (1H) should be inspected and
replaced if they have become distorted or fractured.
4.Clean any accumulation of dirt from the diaphragm case
and orifice (H).
Head on Seat
A
Adjustment & Locknut
1G
Pressure Plate
Fig 5
NOTE: In 1/2” thru 4” sizes, top of valve must be completely assembled
and head must be on seat when measuring dimensions “A” and when
reassembling diaphragms.
Size
Dim.A
1/2” & 3/4”
1/16”
1”
5/64”
1-1/4” & 1-1/2”
3/32”
7
2”
2-1/2”
3”
4”
6”
1/8” 13/64” 13/64”1/4” 27/64”
TROUBLESHOOTING CHART — TYPE 25E
Symptom
Cause
Check and Cure
1. Valve does not close.
1. (a) Dirt under pilot valve head or seat.
1. (a) Remove and, if necessary, replace or clean.
See Figure 6, Page 4.
(b) Dirt in orifices (E) or (H).
(b) Inspect and clean.
(c) Dirt or foreign material under main
valve head (1E).
(c) De-energize solenoid to close pilot. Disconnect tubing at (G). Main valve should close, if not,
remove bolts (1A) and clean main valve.
(d) Faulty control circuit.
(d) Check the electrical system by energizing the
solenoid. A metallic click signifies the solenoid is
open. Absence of the click indicates loss of power
supply. Check for loose or blown out fuses, open
circuited or grounded coil, broken lead wires or
splice connections.
(e) Actuating device, that is, timer, thermostat or programmer may be defective.
(e) Check and correct.
(f) Bypass valve leaking
(f) Check and correct
2. Valve does not open.
2. (a) Actuating device, that is, timer, ther- 2. (a) Check and correct.
mostat or programmer may be faulty.
(b) Main Valve diaphragm (1H) cracked.
(b) Check and correct. Remove copper tubing at
(G) and crack bypass valve. If steam or air blows
from diaphragm case at (G) connection, replace
diaphragm.
(c) Orifice at (H) blocked.
(c) Check and correct. Remove copper tubing at
fitting. Inspect and clean.
(d) Valve strainer (1D) blocked.
(d) Check and correct. Remove bolts (1A). Inspect
strainer and clean.
(e) Steam or air pressure too low.
(e) Check and correct.
(f) Line strainer partially or completely
blocked.
(f) Check and correct. Inspect and clean.
(g) Faulty control circuit.
(g) Check the electrical system by energizing the
solenoid. A metallic click signifies the solenoid is
open. Absence of the click indicates the loss of
power supply. Check for loose or blown out fuses,
open circuited or grounded coil, broken lead wires
or splice connections.
(h) On steam applications, steam trap
draining equipment may not be functioning properly.
(h) Check and repair, if necessary.
Spirax Sarco Applications Engineering Department
Toll Free at:
1-800-575-0394
SPIRAX SARCO, INC. • 1150 NORTHPOINT BLVD. • BLYTHEWOOD, SC 29016
PHONE 803-714-2000 • FAX 803-714-2200
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