Spirax Sarco SRV66 User manual

IM-P186-09 CTLS Issue 6 1
SRV66 Sanitary Pressure Reducing Valve
1. Safety information
2. General product information
3. Installation
4. Operation
5. Commissioning
6. Maintenance
7. Spare parts
© Copyright 2021
Printed in GB
1866350/6
SRV66
Sanitary Pressure Reducing Valve
Installation and Maintenance Instructions
IM- P186-09
CTLS Issue 6

IM-P186-09 CTLS Issue 6
2
SRV66 Sanitary Pressure Reducing Valve
Safe operation of the unit can only be guaranteed if it is properly installed, commissioned and
maintained by a qualified person (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.
1.1 Intended use
Referring to these Installation and Maintenance Instructions, Name-plate and Technical Information
Sheet, check that the product is suitable for the intended use/application. The product complies
with the requirements of the EU Pressure Equipment Directive/UK Pressure Equipment (Safety)
Regulations and falls within Category 'SEP'. It should be noted that products within this category
are required by the Directive not to carry the mark.
i) The product has been specifically designed for use on steam, water and inert industrial
gases. These fluids are in Group 2 of the above mentioned Pressure Equipment Directive. The
product’s 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.
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 occurance, ensure a safety device is included in the system to prevent such
over-limit situations.
iii) Determine the correct installation situation and direction of fluid flow.
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.
v) Remove protective covers from all connections and protective film from all name-plates, where
appropriate, before installation on steam or other high temperature applications.
1.2 Access
Ensure safe access and if necessary a safe working platform before attempting to work on the
product. Arrange suitable lifting gear if required.
1.3 Lighting
Ensure adequate lighting, particularly where detailed or intricate work is required.
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.
1. Safety information

IM-P186-09 CTLS Issue 6 3
SRV66 Sanitary Pressure Reducing Valve
1.6 The system
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.
1.7 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.
1.8 Temperature
Allow time for temperature to normalise after isolation to avoid the danger of burns and consider
whether protective clothing (including safety glasses) is required.
PTFE 'O' ring
If the PTFE 'O' ring used inside the unit has been subjected to a temperature approaching 260°C
or higher, it will give off toxic fumes, which if inhaled is likely to cause temporary discomfort. It
is essential for a no smoking rule to be enforced in all areas where PTFE is stored, handled or
processed as persons inhaling the fumes from burning tabacco contaminated with PTFE particles
can develop 'polymer fume fever'.
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
Consider whether any protective clothing is required by yourself and/or others in the vicinity to
protect against the hazards of, for example, chemicals, high/low temperature, noise, falling objects,
and dangers to eyes and face.
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 these instructions.
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.
Post 'warning notices' if necessary.
1.12 Handling
Manual handling of Spirax-Sarco 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.

IM-P186-09 CTLS Issue 6
4
SRV66 Sanitary Pressure Reducing Valve
1.13 Residual hazards
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 of 180°C.
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 if they
are inoperative in environments where they may be exposed to temperatures below freezing point.
1.15 Safety information - Product specific
This product should not be dismantled without first releasing the compression on the control spring.
1.16 Disposal
This product is recyclable and no ecological hazard is anticipated with its disposal providing due
care is taken, EXCEPT:
PTFE protective film:
-Can only be disposed of by approved methods, not incineration.
-Keep PTFE waste in a separate container, do not mix it with other rubbish, and consign it to
a landfill site.
1.17 Returning products
Customers and stockists are reminded that under UK and 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.

IM-P186-09 CTLS Issue 6 5
SRV66 Sanitary Pressure Reducing Valve
2.1 Description
The SRV66 is an angle pattern self-draining sanitary pressure regulating valve of all 316 type stainless steel
construction suitable for use on steam, water and inert industrial gases. It is available with sanitary clamp
compatible connections to ISO 2852, requires no external pressure sensing line and has clean in place (CIP) and
sterilise in place (SIP) capability.
Typical applications include: Clean steam, gas and liquid supplies to bioreactors, centrifuges, freeze dryers,
sterilisers, autoclaves, process tanks, humidiers and culinary equipment.
Valve tightness
Valve tightness is in accordance with VDI/VDE guideline 2174 (leakage rate < 0.5% of Kvs value).
Standard surface finish and cleaning
Internal wetted parts - Ra < 3.2 µm ultrasonically cleaned.
Note: For additional product data see Technical Information sheet TI-P186-08.
2.2 Sizes and pipe connections
DN15, DN20, DN25, DN32, DN40 and DN50 ISO 2852 sanitary clamp compatible.
Please note: For other end connections contact Spirax Sarco.
2. General product information
Fig. 1 SRV66

IM-P186-09 CTLS Issue 6
6
SRV66 Sanitary Pressure Reducing Valve
The product must not be used in this region.
The product should not be used in this region or beyond its operating range as damage to
the internals may occur.
Body design conditions
Inlet PN10
Outlet see 'Pressure setting range' below
Maximum design pressure 9.5 bar @ 50 °C
Maximum design temperature 300 °C @ 5.8 bar g
Minimum design temperature -10 °C
Maximum operating temperature 180 °C
Maximum operating pressure (inlet) 8 bar g
Minimum operating temperature -10 °C
Designed for a maximum cold hydraulic test pressure of: 15.2 bar g
2.4 Pressure setting range
Size DN15 - DN50
Inlet/outlet rating PN10/PN2.5 PN10/PN6 PN10/PN10
Spring range 0.3 - 1.1 bar g 0.8 - 2.5 bar g 1.0 - 5.0 bar g
Maximum permitted outlet pressure = 1.5 times set pressure
Temperature °C
Pressure bar g
Steam saturation curve
2.3 Pressure/temperature limits

IM-P186-09 CTLS Issue 6 7
SRV66 Sanitary Pressure Reducing Valve
3.1 General information
Before installing the valve thoroughly flush the pipeline. Ideally the valve should be installed in a pressure
reducing valve station, see Figure 2, at the very minimum there should be a separator and strainer fitted
upstream, these should be serviced at regular intervals. The SRV66 should always be fitted with the inlet
horizontal and the spring housing directly above the valve. Most applications will require a safety valve to
be installed downstream in case of accidental overpressure. It should be noted that the valve should not
be used as a shut-off valve, a separate valve should therefore be used for isolation purposes if required.
If it is possible for equipment downstream of the valve to be shut off then a further trap set should be installed
to prevent downstream flooding.
The pressure reducing valve should not be insulated as this may lead to over heating and destroy the
elastomer seals.
Fig. 2
Recommended installation
F
A
B
C
E
D
ASteam trap set
BSeparator
CIsolating valve
DPressure range
ESRV66 pressure reducing valve
FSafety valve
C
D
2.5 Dimensions/weights
(approximate) in mm and kg
Pressure range Size A B C Weight
1.0 to 5.0 bar
and
0.8 to 2.5 bar
DN15 - DN25 90 138 200 2.0
DN32 - DN40 120 138 200 2.5
DN50 120 138 200 3.0
0.3 to 1.1 bar
DN15 - DN25 120 200 200 3.0
DN32 - DN40 120 200 200 3.5
DN50 120 200 200 4.0
B
C
A
A
3. Installation

IM-P186-09 CTLS Issue 6
8
SRV66 Sanitary Pressure Reducing Valve
4.1 How the SRV66 works
As steam or other operating fluid passes through the valve the pressure on the downstream side of
the valve increases and acts directly on the diaphragm. Pressure acting on the area of the diaphragm
transmits a force which acts against that of the control spring. When the downstream pressure exceeds
the set pressure the force acting through the diaphragm will overcome the force of the control spring
and the valve will shut. Conversely, if the downstream pressure is too low then the control spring will
exert sufficient force to open the valve.
Adjustment screw
Control spring
Diaphragm
Steam flow
Controlled
outlet
pressure
Fig. 3 How the SRV66 works
Rotating the adjusting screw clockwise
increases the outlet pressure.
Spring clip
4. Operation

IM-P186-09 CTLS Issue 6 9
SRV66 Sanitary Pressure Reducing Valve
5.1 Start-up and adjustment:
-First make sure that all stop valves are closed.
-Check that the control spring is not compressed, wind the adjuster screw anticlockwise if necessary.
-Open the stop valves in the following order:
i-Open the stop valves immediately in front of the steam traps (C1).
ii -Open the downstream stop valve (C2).
iii -Very gently open the upstream valve on the inlet supply line (not shown) to avoid any sudden
mechanical or thermal shock.
-Slowly turn the adjuster screw clockwise until the desired downstream pressure is achieved (D). If the
valve is set under no-load conditions then there will be a proportional offset causing the controlled
pressure to drop by about 20% under flowing conditions.
If the valve is set under normal flowing conditions then there will be a pressure rise of about 20% due to
the proportional offset of the valve as the load reduces to zero. It is important that any downstream safety
valve (F) is set such that the no-load set pressure of the SRV66 is below the safety valve reseat pressure.
Fig. 4 SRV66 - Commissioning
F
D
C1
SRV66 C2
5. Commissioning

IM-P186-09 CTLS Issue 6
10
SRV66 Sanitary Pressure Reducing Valve
6.1 General inspection
While a programme of planned maintenance is always recommended, the Spirax Sarco SRV66 will give
long and trouble free service if correctly selected, installed and kept 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 after a few days.
Check the following:
-Clean all pipeline filters or strainers (remove elements or screens to clean).
-Check all joints for leakage.
6.2 Inspecting/replacing diaphragm and valve assembly:
-Before attempting any maintenance operation read the product specific safety information in Section 1.15.
-Isolate the valve, first closing the upstream isolating valve (C1) and then the downstream isolating valve
(C2). Check that the pressure is zero (D) and allow the valve to cool (see Figure 5).
-Release the compression on the control spring (5) by turning the adjustment screw (4) anticlockwise.
-Remove the SRV66 from the pipeline.
-Lift off the spring housing (3) and the control spring (5) by first releasing the 'V' band clamp screws (12)
and then removing the 'V' band (9).
-Grip the flats visible on the main valve end and undo the lock-nut (7) clamping the diaphragm (10) and
diaphragm plates (8). Please note: that when refitting the diaphragm plates the side with the radius
should abut the diaphragm face.
-The diaphragm and diaphragm plates (8 and 10) can then be removed from the main valve which should
be carefully lowered and removed via the valve inlet.
Note the diaphragm'O' ring seal (11) which sits against the diaphragm PTFE face on the wetted side.
-Reassemble in reverse order ensuring the PTFE (light colour) side of the two-part diaphragm is on the
wetted side.
Fig. 5 Isolate the valve
C1
SRV66
D
C2
6. Maintenance

IM-P186-09 CTLS Issue 6 11
SRV66 Sanitary Pressure Reducing Valve
Fig. 6 Maintenance
4
7
5
9
3
11
10
12
8

IM-P186-09 CTLS Issue 6
12
SRV66 Sanitary Pressure Reducing Valve
The spare parts available are detailed below. No other parts are supplied as spares.
Available spares
Diaphragm and 'O' ring 10, 11
How to order spares
Always order spares by using the description given in the column headed 'Available spares' and state the
size, model, pressure range and PN rating.
Example:
1 - Diaphragm and 'O' ring and gasket kit for a Spirax Sarco DN25 SRV66 direct acting pressure reducing
valve having a pressure range of 1 to 5 bar, a PN10/PN6 rating and FPM diaphragm.
11
Fig. 7 SRV66 spares
10
7. Spare parts