Spirax Sarco SV615 User manual

IM-P316-03 CTLS Issue 14 1
1. Safety information
2. General product information
3. Supply
4. Handling
5. Before tting the valve
6. Installation
7. Damage prevention
8. Commissioning
9. Testing during use
10. Guidelines for setting
11. Maintenance
© Copyright 2019
Printed in GB
3160050/14
SV615
Safety Valve
Installation and Maintenance Instructions
IM-P316-03
CTLS Issue 14

IM-P316-03 CTLS Issue 14
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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 requirements of the
Pressure Equipment Directive (PED) have been satisfied and, if applicable, the product accordingly
bears the mark:
i) The product has been specifically designed for use on the fluids specified in the Technical
Information Sheets. (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 (suitably guarded) 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

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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 danger of burns.
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
Where the weight of the product exceeds 20 kg it is recommended that suitable lifting equipment
is used to prevent personal injury.
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 in excess
of 200 °C.
Many products are not self-draining. Take due care when dismantling or removing the product from
an installation (refer to Section 11, 'Maintenance').

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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. The soft seal version of this valve (SV615AV and SV615BV) contains a Viton component.
If the valve has been subjected to a temperature approaching 315 °C, the Viton material may have
decomposed and formed hydroflouric acid. Avoid skin contact and inhalation of any dust or fumes
as this acid causes deep burns and damage to the respiratory system.
1.16 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. However, if
the valve is fitted with a Viton seal, special care must be taken to avoid potential health hazards
associated with decomposition/burning of this item.
Viton:
-Can be landfilled, when in compliance with National and Local regulations.
-Can be incinerated, but a scrubber must be used to remove Hydrogen Fluoride, which is evolved
from the product and with compliance to National and Local regulations.
- Is insoluable in aquatic media.
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.

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Safety valve
Reducing
valve
Condensate
Steam supply
2.1 Description
The SV615 full lift, full nozzle safety valve is suitable for steam, air, inert industrial gas and non-hazardous
liquid service.
Available types
Valves are available in sizes ranging from DN15 to DN50 and have a bronze body with female screwed
connections and a stainless steel nozzle. There is also the option of a sanitary clamp inlet connection on
the smaller sizes. All valves have a closed bonnet with either a lifting lever or closed cap (gas tight cap
option). An optional soft seal disc is available in Nitrile (for air up to 120 °C), EPDM (for water) or Viton (for
air up to 200 °C).
Standards and approvals
The SV615 complies with the requirements of EN ISO 4126:2004 and carries the mark indicating full
compliance with the requirements of the Pressure Equipment Directive (PED). The Approval Authority and
Notied Body is the Royal and Sun Alliance.
Seat tightness complies with ASME/API STD 527- Revision 2002.
Certification
A manufacturers' Typical Test Report is provided as standard for each valve which will include valve set and
hydraulic test pressure. Also available on request is material certication in accordance with EN 10204 3.1.
2.2 Sizes and end connections
DN15, DN20, DN25, DN32, DN40 and DN50.
Inlet connections
Screwed BSP (BS 21 parallel) female
Screwed NPT female
1" Sanitary clamp compatible (DN15, DN20 and DN25 sizes only)
BS 4825/ISO 2852/DIN 32676
Outlet connections Screwed BSP (BS 21 parallel) or NPT female
Small bore drain
To safe area
2. General product information
Fig. 1
A typical installation of a safety valve, downstream of a pressure reducing valve station

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The product must not be used in this region.
A - AMaximum operating temperature with metal seat.
A - BMaximum operating temperature with Viton seat.
A - CMaximum operating temperature with EPDM seat.
A - DMaximum operating temperature with Nitrile seat.
Body design conditions PN25
Set pressure range
Maximum
½" to 1¼" 18 bar g
1½" and 2" 14 bar g
Minimum 0.3 bar g
Temperature
Metal seat Minimum -90 °C
Maximum +230 °C
Nitrile seat * Minimum -30 °C
Maximum +120 °C
EPDM seat * Minimum -50 °C
Maximum +150 °C
Viton seat * Minimum -20 °C
Maximum +200 °C
Performance data
Overpressure
Steam 5%
Gas 10%
Liquid 10%
Blowdown limits
Steam, gas 10%
Liquids 20%
Derated coefficient of discharge values
Steam, gas 0.71
Liquid 0.52
Maximum permitted backpressure 10% of set pressure
Tested at a maximum inlet cold hydraulic test pressure of: 37.5 bar g
* Note: Soft seal inserts are not suitable for use on steam applications.
2.3 Pressure/temperature limits
Please contact Spirax Sarco,
when so required, for relevant
details regarding the maximum
allowable limits that the shell
can withstand.
Temperature °C
Pressure bar g
Steam
saturation
curve
Maximum set pressure
for 1½" and 2"
SV615
Maximum set pressure
for 1½" and 2"
SV615

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2.4 Dimensions/weights (approximate) in mm and kg
Connection Flow
Size Inlet Outlet Lift A B C* D Ø E Ø Weight
Screwed
BSPF x BSPF
or
NPTF x NPTF
DN15 ½" ¾" 340 40 194 12 -1.3
DN20 ¾" 1¼" 555 44 229 20 -2.4
DN25 1" 1½" 660 48 242 24 -2.9
DN32 1¼" 2" 7. 2 5 70 58 279 29 -4.2
DN40 1½" 2½" 9.25 81 67 365 37 -8.8
DN50 2" 3" 11.5 0 96 80 420 46 -13.0
Sanitary clamp
DN15 1" ¾" 340 55 209 12 50.5 1.4
DN20 1" 1¼" 555 60 245 20 50.5 2.6
DN25 1" 1½" 660 64 258 24 50.5 3.1
* Applies to sealed cap and lever designs.
D
C
B
A
C
B
A
Sanitary clamp version
Screwed version
Fig. 2
D Ø
E Ø

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2.5 Materials
No. Part Material
1Body Bronze BS EN 1982 CC491KM
2Nozzle
DN15
and
DN20
Stainless steel BS 970 431 S29
DN25
to
DN50
Stainless steel BS 3146 Pt2 Gr. ANC2
Sanitary
connection Stainless steel ASTM A276 316L
3Disc Stainless steel ASTM A276 316L
4Lever housing Bronze BS EN 1982 CC491KM
5Spring Chrome-vanadium alloy steel BS 2803 735 A50 HS
6Stem guide Brass BS 2872 CZ 121
7Spring end plate Brass BS EN 12165 - CW617N
8Stem Stainless steel BS 970 431 S29
9Adjustment screw Brass BS 2874 CZ 121
10 Lever Zinc plated SG iron
11 Pivot pin Stainless steel AISI 304
12 Circlip Stainless steel BS 2056 316 S42
13 Adjuster lock-nut Brass BS 2872 CZ 121
14 Soft seal disc
Stainless steel/Nitrile ASTM A276 316 /bonded Nitrile 4490 (90 IRHD)
Stainless steel/EPDM ASTM A276 316 /bonded EPDM 2064 (75 IRHD)
Stainless steel/Viton ASTM A276 316 /bonded Viton F81 (85 IRHD)
15 Sealed cap Bronze BS EN 1982 CC491KM
16 Cap seal Nitrile BS 2874 CZ 121
17 Skirt Brass BS 2874 CZ 121
18 Grub screw Steel
19 Ball Stainless steel

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Soft seal disc option
14
Sealed
cap option
15
16
18
4
11
9
7
10
1
3
12
6
5
2
13
17
8
Fig. 3
19
1" Sanitary clamp
version
Screwed version

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2.6 How to select a SV615 safety valve
Model type SV615 SV615
Configuration
A=Closed bonnet/easing lever
A
B=Closed bonnet/sealed cap
Seal material
S=Stainless steel
N
N=Nitrile
E=EPDM
V=Viton
Finish
P=Electroless nickel plated (ELPN)
Q = ELNP with stainless steel name-plate
Size
DN15, DN20, DN25, DN32, DN40 and DN50 DN15
BSPF xBSPF BSPF
x
BSPF
Connection
(inlet x Outlet)
NPTF xNPTF
Clamp xBSPF
Selection example Please note if ELNP nish is required, add 'P'.
SV615 A N DN15 BSPF x BSPF
How to order example: 1 o󰀨 Spirax Sarco SV615AN safety valve having DN15 screwed BSPF
x BSPF connection, set at 6 bar g.

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5.1 Ensure that the installation is correct (Figure 1, page 5).
5.2 Blow through the pipewor k to ensure that it is completely free of any foreign matter that may other wise
pass to the valve seat and cause damage, leading to seat leakage. Blowdown must be carried out
before installing the safety valve.
5.3 Ensure that valve is set to the correct pressure, see 'Testing during use', Section 9.
Normally, the valve will be supplied set at the required pressure and sealed.
Setting of Spirax Sarco safety valves must only be carried out by authorised, competent persons.
Spirax Sarco accepts no responsibility for valves which have been reset by unauthorised persons.
4.1 Valves should be transported in the upright position.
4.2 Do not drop and avoid sudden shocks or heavy impacts.
4.3 Always store in the suppliers packaging until required.
4.4 Never carry a safety valve by the lifting lever.
3. Supply
4. Handling
5. Before fitting the valve

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Note: Before actioning any installation observe the 'Safety information', Section 1.
CAUTION !
Take care if using liquid jointing compounds (particularly thread sealants such as 'Loctite' or 'Stag') that
these don't contaminate internal seating faces.
In extreme cases, this type of contamination may cause these faces to stick together, causing a potentially
dangerous overpressure situation.
6.1 The valve should always be mounted vertically upwards with its main axis vertical.
6.2 The valve should be fitted to the pipework or vessel by means of the shortest possible length of
pipe or fitting.
6.3 There should be no intervening valve or fitting i.e. it should not be possible to isolate the safety
valve (Figure 4).
6.4 The inlet pipe connection should not be smaller than the valve (see Figures 7 and 8).
6.5 Built up backpressure occurs as a result of a safety valve relieving into the discharge pipework.
To ensure adequate system protection and correct safety valve performance, Spirax Sarco
recommend that this built up backpressure does not exceed 10% of the gauge set pressure. This
value may be exceeded even when using short runs of pipework of the same nominal bore as the
safety valve outlet.
It is the responsibility of the installer/owner to ensure that this requirement has been met by carefully
considering the nominal bore and length of the discharge pipe, as well as the type and quantity of
bends and pipe fittings to be installed.
Long radius bends and fittings are recommended.
Where there is any doubt as to the suitability of the discharge pipework system, please contact
Spirax Sarco for further guidance.
6.6 Direct the outlet pipework to a safe point of discharge where there is no risk of injury to persons or
damage to property in the event of the valve operating.
6.7 The outlet pipework should be adequately supported such that it does not place undue stress on
the safety valve.
6.8 Where the outlet pipework is directed upwards a small bore drain should be provided at the lowest
point (Figure 5). This drain should be taken to a place where any discharge will not create a hazard
or inconvenience.
6.9 Each safety valve should have its own unrestricted discharge pipe.
6.10 Safety valves should not be lagged.
6.11 Safety valves can operate very suddenly and will be too hot to touch without protection when
installed on steam systems.
6.12 Always use a wrench on the hexagon to secure the valve to the inlet pipe. Do not use pipe grips on
the body. Do not use excessive leverage or force.
6. Installation

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Fig. 4
Fig. 5
Discharge to safe area
To safe
small bore
drain area
Not drawn to scale

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Excessive pressure loss at the inlet of a safety valve
when it operates will cause extremely rapid opening
and closing of the valve, observed as chattering or
hammering.
This may result in reduced capacity as well as
damage to seating faces and the other parts of
the valve.
When normal pressure is restored it is possible that
the valve will leak.
7.1 Solution
The safety valve should be fitted 8-10 pipe diameters
downstream of any converging or diverging fittings
or bends, see Figure 6.
Inlet branches should be as Figure 7 or 8. Fig. 6
Fig. 7 Fig. 8
a
Inlet area 'A'
is approximately twice that of area 'a'.
r
Radius 'r' not less than inlet diameter
8 - 10 pipe diameters downstream
of converging 'Y' fittings or bends.
7. Damage prevention

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Note: Use suitable protection against excess heat and noise when testing safety valves.
It is recommended that the safety valve is tested for correct operation on a regular basis as part of a
documented and controlled procedure, the frequency of testing is dependant on the application and system
conditions and an appropriate test interval must be decided by the user or relevant insurance company.
Some valves are fitted with standard (open type) levers to enable testing for correct operation during use.
Do not operate the lever unless the system pressure is at least 85% of the safety valve set pressure.
Do not use any tool or mechanical device (e.g. length of pipe) on the lever.
Do not apply excessive force - Hand operation only.
8.1 Once the valve has been fitted check that there are no leaks from either the inlet or the outlet
connections.
8.2 Test the valve by raising the system pressure. Check that the valve operates at the correct set
pressure.
8.3 Reduc e the system pressure to the normal operating pressure and check that the safety valve reseats.
9. Testing during use
8. Commissioning

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It can be seen that the safety valve does not re- seat when the pressure falls to the safet y valve set pressure.
There must be adequate differential between the maximum system operating pressure and the safety valve
set pressure if the valve is to re-seat.
The maximum system operating pressure is most likely to occur during no -load conditions. Figure 10 shows
the range within which the valve must be set.
10.1 Choice of set pressure
A decision must be made regarding the pressure at which the safety valve should be set.
The maximum set pressure, in accordance with BS 5500, is the safe working pressure of the plant it protects
and the valve must achieve its rated capacity with an overpressure of no more than 10%.
The SV615 achieves its rated capacity at 5% overpressure on steam, 10% on air. If the valve is set too close to
the operating pressure of the system the valve may operate prematurely. It will also fail to close satisfactorily
when normal operating pressure is restored.
Figure 9 outlines the way a safety valve operates.
Fig. 9
(Valve operates)
Time
Re-seat differential
Pressure
Set
pressure
Full lift position
5% of set pressure
Re-seat pressure
(10% of set pressure)
10. Guidelines for setting
(By authorised and competent persons only)

IM-P316-03 CTLS Issue 14 17
Fig. 10
Flowrate =Maximum rating of pressure reducing valve
A=10% of safety valve set pressure, 0.3 bar minimum
B = Normal system pressure variation
Note: The operating pressure of a system will var y and it is impor tant that the safety valve is set high enough
to accommodate such fluctuations.
10.2 Setting the valve
Spirax Sarco cannot be held responsible for unauthorised alteration of the set pressure.
Although not mandator y, Spirax Sarco recommend that SV615 metal seated valves for steam service should
be cold set on a test rig at 3% above the required set pressure. This does not apply if the valve is set on steam.
10.3 Valves supplied unset
Valves supplied unset to approved agents will include a set pressure tag to be stamped with the appropriate
set pressure in bar after setting.
The tag should be permanently attached to the valve when using the locking wire and polypropylene seal.
The back of the blue instruction label affixed to each unset valve will indicate the pressure range of the
spring fitted.
Re-seat differential
B
Operating pressure
No load condition
Maximum system
operating pressure
Maximum allowable
working pressure
or design pressure
of vessel
Maximum setting of
safety valve
A
Safety valve may
be set within
this range
Minimum setting of
safety valve

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All safety valves should receive planned maintenance.
Note: Before actioning any maintenance work please read 'Safety information', Section 1.
It is recommended that Spirax Sarco safety valves are returned to your local Spira x Sarco agent for a thorough
overhaul periodically (please read 'Returning products', Section 1.17).
The valve will be returned having been overhauled, tested re-set and sealed in accordance with industry
standard procedures.
11. Maintenance

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