PTF4 Pivotrol® Pump patented version Dual Mechanism

PTF4 Pivotrol® Pump patented version Dual Mechanism
IM-P135-14
ST Issue 2
PTF4 Pivotrol® Pump (patented) version
Dual Mechanism - Pressure Powered Pump
Installation and Maintenance Instructions
1. Safety information
2.General
product information
3.Installation
4.Commissioning
5.Operation
6. maintenance
7. Fault finding
IM-P135-14 ST Issue 2
© Copyright 2013
1
Printed in the USA
1. Safety information
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.
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.
The product complies with the requirements of the European Pressure Equipment
Directive 97 / 23 / EC, Group 2 gases to Category 3 and carries the
mark when so
required.
i) The product has been specifically designed for use on steam 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.
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.
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 a steam or other high
temperature applications.
1.2Access
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.
1.3Lighting
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.
1.6 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.
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IM-P135-14 ST Issue 2
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.
1.8Temperature
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 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.
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.
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.
1.12Handling
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.
1.13 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 204.5°C (400°F).
Take due care when dismantling or removing the product from an installation
(refer to Section 6 'Maintenance instructions').
1.14Freezing
Provision must be made to protect systems which are not self-draining against
frost damage in environments where they may be exposed to temperatures below
freezing point.
1.15Disposal
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.
IM-P135-14 ST Issue 2
3
2. General product information
2.1Description
The Spirax Sarco Pivotrol® Pump (patented) is a non electric pump which transfers high
temperature condensate, or other liquids from a low point, low pressure or vacuum space to an
area of higher pressure or elevation. This self-contained unit including PowerPivot® technology
(patented) uses steam, compressed air or any other suitable pressurised gas as the pumping
force.
The standard Pivotrol® PTF4 Pump will handle liquids from 0.88 to 1.0 specific gravity.
Warranty
1 year.
Accessories:
- Reflex type gauge glass.
- Insulation cover.
Standard
This product fully complies with the requirements of the European Pressure Equipment
Directive 97 / 23 / EC.
Certification
This product is available with certification to EN 10204 3.1. Note: All certification /
inspection requirements must be stated at the time of order placement.
Note: For further product data see the following Technical Information Sheet, TI-P135-13.
2.2 Sizes and pipe connections
Inlet and Outlet:
4" x 4" (DN100 x DN100) ASME Class 150 threaded flange (NPT) or
Socket weld
Motive:
½" Screwed NPT or Socket weld
Exhaust:
1" Screwed NPT or Socket weld
4
IM-P135-14 ST Issue 2
Please note that pressure
gauges may be fitted into
any of the top gauge glass
connectors.
Vent assist valve
Vent assist valve
Gauge
glass
connection
Gauge
glass
connection
Operating pressure range
2 to 13.8 bar g
(30 to 200 psi g)
Fig. 1
IM-P135-14 ST Issue 2
5
Pressure psi g
Steam
saturation curve
Pressure bar g
Temperature °F
Temperature °C
2.3 Pressure / temperature limits (ISO 6552)
The product must not be used in this region.
Body design condition ASME Section VIII, Division 1
PMA Maximum allowable pressure 13.8 bar g @ 204°C(200 psi g @ 400°F)
TMA Maximum allowable temperature 343°C @ 8.6 bar g(650°F @ 125 psi g)
Minimum allowable temperature
-28.9°C(-20°F)
PMO Maximum operating pressure
13.8 bar g(200 psi g)
TMO Maximum operating temperature
198°C(388°F)
for saturated steam service
Minimum operating temperature
-28.9°C(-20°F)
Note: For lower operating temperatures consult Spirax Sarco
Minimum motive differential required:
0.5 bar g(7 psi g)
Maximum backpressure: 75% of motive pressure
Designed for a maximum cold hydraulic test pressure of: 20.7 bar g
(300 psi g)
Note: With internals fitted, test pressure must not exceed: 20.7 bar g
(300 psi g)
Specific gravity of pumped liquid 0.88 to 1.0
Please contact: Spirax Sarco for the product specific Technical Information sheet for the
cycle counter.
Filling head requirements
Filling head
above pump cover
Filling height
from base of pump
305 mm (12")
1125 mm (44.3")
Maximum filling head
1 524 mm (60")
2 337 mm (92.0")
Minimum filling head
-76 mm (-3")
744 mm (29.3")
Standard recommended
Maximum number of cycles per minute = 6
6
IM-P135-14 ST Issue 2
3. Installation
Note: Before actioning any installation observe the 'Safety information' in Section 1.
Referring to the Installation and Maintenance Instructions, name-plate and Technical
Information Sheet, check that the product is suitable for the intended installation:
3.1
Check materials, pressure and temperature and their maximum values. If the maximum
operating limit of the product is lower than that of the system in which it is being fitted,
ensure that a safety device is included in the system to prevent overpressurisation.
3.2
Determine the correct installation situation and the direction of fluid flow.
3.3
Remove protective covers from all connections and protective film from all
name-plates, where appropriate, before installation on a steam or other high
temperature applications.
3.4
Recommended installation of the PTF4 Pivotrol® Pump when fitted with a reservoir or
vented receiver. In an 'open' system flash steam must be vented or condensed ahead
of the pump inlet. Application details will dictate which of the following options will be
necessary to accomplish this.
It is highly recommended by Spirax Sarco that an adequately sized overflow is fitted to
all condensate receivers. This should be considered best practice and overflows should
only be excluded from installations in exceptional circumstances. Discharge from both
overflows and vent pipes must be piped to a safe location, such that there is no risk to
personnel. In the event of pump or system malfunction or overload, very hot condensate
may be discharged from the overflow, or the vent pipe, or both. Where the vent pipe is
not piped to a pit, or similar safe location, the use of a vent head to reduce the chance
of entrained hot condensate spraying out of the vent is recommended.
Overview connection - The overflow piping must be used on a vented system. Overflow
connections are required to ensure that in the event of pump or system malfunction,
condensate will run in a controlled manner, from the condensate receiver to a safe location,
such as a drain (subject to temperature and local regulations) or to an alternative safe location.
The overflow piping must be a 'U' bend water seal which has a 304 mm (12") minimum depth.
Once primed on start-up the water seal is self-filling and should be piped to a suitable drain.
The addition of the overflow provides a safety mechanism ensuring the pressure within the
receiver does not increase. The overflow is also a tool to diagnose system problems. In the
event of the overflow spilling fluid the operator is immediately made aware of a system problem.
This could include failed traps feeding the package failed pump and changes in system loads
and overloaded receiver.
Pump or system malfunction which could cause the receiver to overflow, can occur for
many reasons. These include; loss of motive steam due to blockage or incorrect operation,
mechanical failure of the pump mechanism or associated check valves, blockage of the
condensate inlet strainer of closure of the pumped return line and system shutdowns.
Overflows will normally be a minimum of 40 mm (1½") in diameter, but may need to be larger
for high capacity units such as packaged PTF4, or where the length of overflow pipe run,
between receiver and discharge point, is more than 6 ft (2 metres). A general 'rule of thumb'
based on a 2 m (6 ft) pipe run and a head of 0.6 m (2 ft):
Condensate loads from:
0 to 4 889 kg / h
(0 to 11 000 lb / h) use a DN40 (1½")
Condensate loads from:
Condensate loads from: 9 977 to 17 959 kg / h (22 000 to 39 600 lb / h) use a DN80 (3")
Normally overflow connections will be fitted with a 'loop seal' arrangement or a suitably sized float trap,
to prevent steam escaping via the overflow connection.
IM-P135-14 ST Issue 2
4 889 to 9 977 kg / h (11 000 to 22 000 lb / h) use a DN50 (2")
7
3.5Vented receivers
To drain condensate from single or multiple sources in an 'open' system, a vented
receiver should be installed in a horizontal plane ahead of the pump. Sufficient volume
is needed above the filling head level to accept the condensate reaching the receiver
during the pump discharge stroke. More importantly, the receiver must be sized to allow
sufficient area for complete flash steam separation from the condensate. Table 1, page 9,
illustrates proper vented receiver sizing (per criteria set forth in the A.S.H.R.A.E.
Handbook) based on the amount of flash steam present. By sizing the receiver as shown
in Table 1 there will be sufficient volume for condensate storage and sufficient area for
flash steam separation. The receiver can be a length of large diameter pipe or a tank.
A receiver overflow piping should be installed as shown in Figure 2 and piped to a
suitable drain. The piping must form a loop type water seal at least 304 mm (12") deep
immediately after the receiver.
3.5.1 Install the pump physically below the receiver to be drained with the exhaust connection
vertically upwards. The pump should be installed with the recommended filling head (the
vertical distance between the top of the pump and the bottom of the receiver) as shown
in Figure 2. For other filling head variations, see the Capacity Table on TI-P135-13.
3.5.2 To prevent equipment flooding during the pump discharge stroke, a vented receiver
should be installed in a horizontal plane ahead of the pump as shown in Figure 2. For
the correct receiver sizing, refer to Table 1. All inlet line fittings must be fully ported.
3.5.3 Connect the vented receiver to the inlet check valve on the pump. Connect the
discharge to the return main or other installation point. For best performance,
horizontal runs immediately ahead of the inlet check valve should be kept to a
minimum. Connect the discharge to the return main or other installation point. Where
the return line rises to a high level directly after leaving the pump a second
check valve should be fitted at the highest point, either in the horizontal or
vertical run, to prevent water from falling back on the outlet check valve of
the pump and reducing its service life. This prevents waterhammer in the
condensate return line.
Note: To achieve rated capacity and maintain the pumps warranty, each pump
must be installed with the check valves as supplied by Spirax Sarco, except
at the inlet on a sump pit application as shown in Figure 9.
3.5.4 Connect the operating medium (steam, air or gas) supply inlet in the cover. Supply main
should have a strainer and steam trap (steam service) or drain trap (air or gas service)
installed upstream of the supply inlet. The steam trap / drain discharge should be piped
into the receiver ahead of the pump for steam systems. For increased service life
operate the pump with motive pressures of 1 to 1.3 bar g (15 to 20 psi g) above
the pump backpressure, while ensuring the maximum required pump capacity is
still achieved.
Note: When available motive pressure exceeds 13.8 bar g (200 psi g), a Spirax
Sarco pressure reducing valve is required to reduce pressure to the pump. The
PRV should be located as far from the pump as possible. For best operation,
motive pressure should be reduced to the minimum required to overcome pump
backpressure and achieve the desired capacity. A safety relief valve should be
installed at the connection provided in the pump cover or in the motive supply
piping.
3.5.5 Any horizontal runs in the exhaust line should be pitched so that the line is self-draining.
The exhaust line should be piped, unrestricted, to atmosphere as shown in Figure 2.
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IM-P135-14 ST Issue 2
Vent to atmosphere. The vent should be piped to a safe
location such that there is no risk to personnel. The use
of a VHT vent head is recommeded if the vent is not
piped to a pit or similar location.
Condensate
inlet
At least
304 mm (12")
seal on the
overflow.
Discharge to
be piped to
safe location
such that there
is no risk to
personnel.
Vent to
atmosphere
Check valve
to help reduce
the likelihood
of backflow and
waterhammer
Motive steam
or gas supply
Condensate
return
line
Pump
exhaust
Vented receiver
Height
Strainer
Filling
head
Overflow
TD
*
Strainer
Filling
height
PTF4
* Minimum 304 mm (12") above the vent assist valve
Fig. 2 Typical installation - Vented pump system
Table 1 Vented receiver sizing for the PTF4
Flash steam
up to:
454 kg / h)
(1 000 lb / h)
907 kg / h)
(2 000 lb / h)
1 361 kg / h)
(3 000 lb / h)
1 814 kg / h)
(4 000 lb / h)
2 268 kg / h)
(5 000 lb / h)
2 722 kg / h)
(6 000 lb / h)
3 175 kg / h)
(7 000 lb / h)
3 629 kg / h)
(8 000 lb / h)
in mm and (inches)
Length
Vent line
diameter
400 mm (16")
1 524 mm (60")
150 mm (6")
500 mm (20")
1 524 mm (60")
200 mm (8")
600 mm (24")
1 524 mm (60")
200 mm (8")
650 mm (26")
1 524 mm (60")
250 mm (10")
700 mm (28")
1 524 mm (60")
250 mm (10")
750 mm (30")
1 829 mm (72")
300 mm (12")
800 mm (32")
1 829 mm (72")
300 mm (12")
900 mm (36")
1 829 mm (72")
350 mm (14")
Diameter *
Pipe size
* Note: The receiver can be made from pipe as shown or be a fabricated tank.
IM-P135-14 ST Issue 2
9
3.6 Open system considerations
The pump will not satisfactorily operate below a motive pressure of 2 bar g (30 psi g).
The steam inlet pipework must allow for an equal quantity of steam to be fed into each
of the two mechanisms. For this to happen the steam inlet pipework must be of equal
pipe size and length when split into two lines from the main steam inlet pipework. For
the customer’s convenience and to ensure correct steam inlet hook-up the option has
been made available to purchase an inlet piping assembly.
At a minimum, when using steam, the inlet piping should be at least 50 mm (2") NB
pipe from the steam header dropping to the pump. Only when the steam (motive) inlet
pipework is close to 0.6 m (2 ft) to the pump should the motive line piping be reduced
and split equally into two separate lines. These should be of equal diameter and length
to be fed into each mechanism’s motive inlet. This will ensure steam (air or motive gas) is
supplied uniformly to each of the PTF4 pump mechanisms and will provide synchronous
operation of both mechanisms.
When the PTF4 is placed in an 'open / vented system' the vent assist valve must be piped
to atmospheric pressure without restriction to ensure correct operation. Any backpressure
acting on the vent assist valve will reduce its ability to open and function correctly.
When the PTF4 is placed in an 'open / vented system' the vent line from the exhaust valve
must be piped into the vent line from the vent assist valve. To ensure no backpressure
is placed on the vent assist valve the vent line from the exhaust valve must be tied in at
least 304 mm (12") above the vent assist valve.
3.7 Installation - Closed loop systems (Figure 3)
A closed-loop installation is one in which the exhaust line of the pump is piped back
(pressure equalised) to the reservoir being drained.
Before breaking any connections on the pump or piping system every
effort should be made to ensure all internal pressure has been relieved and
the motive supply line is shut off to prevent inadvertent discharge of the pump.
When breaking any connection, piping / bolts should be removed slowly so that
if the line is under any internal pressure, this fact will be apparent before completely
removing the pipe or component. Always relieve pressure before breaking any joint.
3.7.1 Install the pump physically below the equipment being drained with the exhaust
connection vertically upwards. The pump should be installed with the recommended
filling head (the vertical distance between the top of the pump and the bottom of the
reservoir) as shown in Figure 3. For other filling head variations, see the Capacity Table
on TI-P135-13.
3.7.2 To prevent equipment flooding during the pump discharge stroke, a reservoir pipe
should be installed in a horizontal plane ahead of the pump as shown in Figure 3. For
the correct reservoir sizing, refer to Table 2 'Inlet reservoir piping'. All inlet line fittings
must be fully ported. If desired, overflow piping can be installed using a properly sized
float and thermostatic trap. The trap inlet should be located at the maximum allowable
water level, at or near the top of the reservoir, and it should discharge to a suitable drain.
3.7.3 For best performance, horizontal piping runs immediately ahead of the inlet check
valve should be kept to a minimum. Connect the discharge to the return main or other
installation point. Where the return line rises to a high level directly after leaving
the pump a second check valve should be fitted at the highest point, either in the
horizontal or vertical run, to prevent water from falling back on the outlet check
valve of the pump and reducing its service life. This prevents waterhammer in the
condensate return line.
Note: To achieve rated capacity, and maintain the pumps warranty, the pump must be
installed with check valves as supplied by Spirax Sarco.
10
IM-P135-14 ST Issue 2
To size the PTF4 in a closed system:
Establish the available motive pressure.
Establish the static backpressure on the pump-trap combination.
Place established pressures (bar g or psi g) into the formulae below:
Pump motive pressure – Minimum vent assist valve* delta P > Backpressure
Capacity charts to be read as normal, i.e. at the pump motive and backpressure.
If, the Pump motive pressure – Minimum vent assist valve* delta P < Backpressure,
then isolate or remove the vent assist valve and multiply the capacity by 0.77 to find
the reduced capacity without the vent assist valve.
* Please note that the vent assist valve is
clearly identified in Figure 1, page 5.
Check
valve
Condensate
return
line
Heat exchanger
Motive steam
or gas supply
Pump
exhaust
Height
Reservoir
Strainer
TD
Filling
head
Filling
height
†
Strainer
PTF4
† Minimum 304 mm (12") above the vent assist valve
Fig. 3 Closed loop system with trap
IM-P135-14 ST Issue 2
11
3.7.4 Inlet reservoir piping - To drain condensate from a single piece of equipment in a 'closed
loop system', a reservoir should be installed in a horizontal plane ahead of the pump.
Sufficient reservoir volume is needed above the filling head level to accept condensate
reaching the pump during the discharge stroke. Table 2, page 11, illustrates the minimum
reservoir sizing, based on condensate load, needed to prevent equipment flooding during
the pump discharge stroke. The reservoir can be a length of large diameter pipe or a
tank see Table 2.
3.7.5 Connect the operating medium supply to the motive supply inlet in the cover. The supply
main should have a strainer and steam trap installed upstream of the supply inlet. The
steam trap discharge should be piped to the downstream piping (Non-flooded).
Note: When the available motive pressure exceeds 13.8 bar g (200 psi g), a
Spirax Sarco pressure reducing valve is required to reduce pressure to the pump.
The PRV should be located as far from the pump as possible. For best operation,
motive pressure should be reduced to the minimum required to overcome
backpressure and achieve the desired capacity. A safety relief valve should be
installed at the connection provided in the pump cover or in the motive steam
supply piping.
3.7.6 The exhaust line must be piped, unrestricted, to the top of the reservoir in order to equalize
all pressures and ensure that the condensate drains by gravity. On vacuum systems the
exhaust line may be connected to the steam space being drained. A thermostatic air vent
should be installed at the highest point of the exhaust line to vent all non-condensibles
during start-up. Any horizontal runs in the exhaust line should be pitched so that the line
is self-draining.
3.7.7 If at any time the backpressure against the pump is less than the pressure in the
equipment being drained, a properly sized float and thermostatic trap must be installed
between the pump and discharge check valve as shown in Figure 3.
3.8 Closed system considerations
3.8.1 The pump will not satisfactorily operate below a motive pressure of 2 bar g (30 psi g).
3.8.2 The steam inlet pipework must allow for an equal quantity of steam to be fed into each
of the two mechanisms. For this to happen the steam inlet pipework must be of equal
pipe size and length when split into two lines from the main steam inlet pipework. For
the customer’s convenience and to ensure correct steam inlet hook-up the option has
been made available to purchase an inlet piping assembly.
3.8.3 At a minimum, when using steam, the inlet piping should be at least 50 mm (2") NB
pipe from the steam header dropping to the pump. Only when the steam (motive) inlet
pipework is close to 0.6 m (2 ft) to the pump should the motive line piping be reduced
and split equally into two separate lines. These should be of equal diameter and length
to be fed into each mechanism’s motive inlet. This will ensure steam (air or motive gas) is
supplied uniformly to each of the PTF4 pump mechanisms and will provide synchronous
operation of both mechanisms.
3.8.3 When the PTF4 is placed in a closed system the exhust line from the exhaust valve must
be piped into the exhuast line from the vent assist valve. To ensure no backpressure is
placed on the vent assist valve the exhuast line from the exhaust valve must be tied in
at least 304 mm (12") above the vent assist valve:
-In an open system, the backpressure acting on the exhaust side of the vent assist valve
(VAV) will be atmospheric pressure.
-When the pump is fitted in a closed system, the backpressure acting on the exhaust
side of the vent assist valve (VAV) is the closed system pressure.
- The maximum possible closed system pressure acting on the exhaust side of the vent
assist valve will be the static backpressure acting on the pump-trap combination.
If the closed system pressure were higher than the static backpressure on the pump trap combination the condensate would flow through both the pump and trap. The
pump would not operate.
12
IM-P135-14 ST Issue 2
Fig. 4 Closed loop system with trap
Check
valve
304 mm (12")
* Minimum
above the vent assist valve
Condensate
return
line
Heat exchanger
Motive steam
or gas supply
Pump
exhaust
Height
Reservoir
Strainer
TD
Filling
head
Filling
height
*
Strainer
PTF4
Table 2 Inlet reservoir piping for the PTF4
Liquid load
kg / h
(lb / h)
4 535
(10 000
9 070
(20 000
13 605
(30 000
18 141
(40 000
22 676
(50 000
27 211
(60 000
kg / h)
lb / h)
kg / h)
lb / h)
kg / h)
lb / h)
kg / h)
lb / h)
kg / h)
lb / h)
kg / h)
lb / h)
in mm and (inches or feet)
Reservoir pipe size
Note: When the backpressure or motive pressure is less than 50%,
these reservoir lengths can be reduced by half
300 mm (12")
400 mm (16")
500 mm (20")
600 mm (24")
1 524 mm (5 ft)
914 mm (3 ft)
610 mm (2 ft)
3 048 mm (10 ft) 2 133 mm (7 ft)
1 219 mm (4 ft)
2 743 mm (9 ft)
1 828 mm (6 ft)
1 219 mm (4 ft)
3 658 mm (12 ft)
2 286 mm (7.5 ft)
1 828 mm (6 ft)
2 743 mm (9 ft)
1 828 mm (6 ft)
2 743 mm (9 ft)
1 828 mm (6 ft)
IM-P135-14 ST Issue 2
13
3.9 Installation - Multiple pressure powered pumps
To ensure even wear and extended service life of each of the pumps in a multiple pump
set the pumps should not be staged so that a primary pump operates continuously and the
secondary pump seldom operates. Each pump should be piped to ensure even operation of
each pump. When piping multiple pumps into a single return line an additional check valve
should be fitted in the single return line to reduce the likelihood of waterhammer in the return
line due to high flowrates and velocities induced during multiple pump discharge cycles.
3.10 PTF4 steam inlet / exhaust pipe - Hook-up
The PTF4 motive supply line should be sized correctly to ensure sufficient motive capacity during
the pumping stroke. A correctly sized inlet pipe will prevent pressure spikes and dips during the
pumping stroke and ensure smooth operation and published capacities are met.
At a minimum, when using steam, the inlet piping should be at least 50 mm (2") NB pipe from
the steam header dropping to the pump. Only when the steam (motive) inlet pipework is close
to 0.6 m (2 ft) to the pump should the motive line piping be reduced and split equal into two
separate lines. These should be of equal diameter and length to be fed into each mechanism’s
motive inlet. This will ensure steam (air or motive gas) is supplied uniformly to each of the PTF4
pump mechanisms and will provide synchronous operation of both - See Figures 5, 6 and 7.
Hook-up of the exhaust lines running from the pump must be clear and free to atmosphere when
piped in an open system, and clear and free when piped into the reservoir in a closed system.
The vent assist valves must be piped directly into either the pump’s receiver or, the pump’s
vent line. In the case of the latter the vent assist valve exhaust line must be piped into the vent
line at least 304 mm (12") away from the pump exhaust connection. Trap discharge pipelines
must not be piped into any of the pumps vent lines - See Figures 8 and 9 on pages 16 and 17.
Digital counter
Steam
inlet
½" Flex hose
Vent assist valve
Strainer
*
UTD52L
* Optional
Ball
valve
Gauge glass
Ball
valve
*
Trap discharge
Fig. 5
Recommended
steam inlet piping hook-up
For pressure /
temperature limits
see Section 2.3
14
IM-P135-14 ST Issue 2
Fig. 6
Recommended
steam inlet piping hook-up
For pressure /
temperature limits
see Section 2.3
Motive steam
inlet
UTD52L
Pipe discharge to
condensate return line
or to safe place
Fig. 7
Recommended
steam inlet piping hook-up
IM-P135-14 ST Issue 2
15
Thermostatic air vent
Condensate
inlet
Check
valve
Alternate vent assist valve pipe hook-up
Exhaust valve pipe
Exhaust
valve
pipe
Reservoir
Vent assist valve
exhaust pipe
Min.
304 mm
(12")
PTF4
Condensate
return
Fig. 8 Typical PTF4 exhaust and vent assist valve pipe hook-up for closed system
3.11 Start-up procedure
3.11.1 Slowly open the supply (steam, air or gas) to provide pressure at the pressure power
pump inlet valve. Check that trap / drainer on motive line is operational.
3.11.2 Open the gate valves in the pressure power pump inlet and discharge lines.
3.11.3 Open valve(s) ahead of the unit allowing condensate to enter the receiver / reservoir
and fill the pressure power pump body. The pump will discharge when full.
3.11.4Observe operation for any abnormalities. Pressure power pump(s) will cycle
periodically with an audible exhaust at the end of the pumping cycle. If any
irregularities are observed, recheck the installation instructions for correct hook-up
(See following pages). Consult Spirax Sarco if necessary.
3.11.5If the overflow piping has been provided, check that a water seal has been
established to prevent any steam from being vented during normal operation. Prime
the overflow piping if necessary.
16
IM-P135-14 ST Issue 2
Vent to atmosphere. The vent must be piped to a safe
location such that there is no risk to personnel. The use of
a VHT vent head is recommeded if it can not be piped to a
pit or similar location.
Condensate
inlet
Alternate vent assist
valve pipe hook-up
Exhaust valve pipe
Vented
receiver
Vent assist valve
exhaust pipe
Min.
304 mm
(12")
Min.
304 mm
(12")
At least 304 mm
(12") seal on
the overflow.
Discharge to be
piped to a safe
location such that
there is no risk to
personnel.
PTF4
Condensate
return
Fig. 9 Typical PTF4 exhaust and vent assist valve pipe hook-up for open (vented) system
4. Commissioning
After installation or maintenance ensure that the system is fully functioning. Carry out tests
on any alarms or protective devices.
Note: As with all steam systems it is very important that the pressure is built up slowly to
avoid possible damage to any sensitive equipment.
IM-P135-14 ST Issue 2
17
5. Operation
How the Pivotrol Pump® operates
.1.1 In the normal position before start-up the float (18) is at its lowest position with the steam
5
inlet valve (4) closed, the exhaust valve (6) is open.
5.1.2 When liquid flows, by gravity, through the inlet check valve (21) into the pump body,
the float (18) will become buoyant and rise.
5.1.3As the float (18) continues to rise the float arm assembly (14) is engaged which
increases the compression in the spring (13). When the float (18) has risen to its upper
tripping position the energy in the spring is released instantaneously causing the float
arm assembly (14) to snap upwards over center moving the pushrod (9) upwards
to simultaneously open the steam inlet valve (4) and close the exhaust valve (6).
5.1.4 Steam will now flow through the steam inlet valve (4) and develop a pressure within the
body forcing the liquid out through the discharge check valve (21). The inlet check
valve (21) will be closed during the discharge cycle.
5.1.5 As the liquid level in the pump body lowers so does the float’s (18) position. Before
the float (18) reaches its lowest position the float arm assembly (14) is engaged
increasing the compression in the spring (13). When the float (18) is at its lower
tripping position in the body the energy in the spring (13) is released instantaneously
causing the float arm assembly (14) to snap over center downward moving the
pushrod (9) down causing the steam inlet valve (4) to close and exhaust valve (6) to
open simultaneously.
5.1.6 Liquid will again flow through the inlet check valve (21) to fill the pump body and the
cycle will be repeated.
18
IM-P135-14 ST Issue 2
Operating pressure range 2 to 13.8 bar g (30 to 200 psi g)
Exhaust outlet
Motive inlet
Cross
sectional
view
7
Please note that pressure
gauges may be fitted into
any of the top gauge glass
connectors.
5
4
6
19
9
22
8
23
2
2
3
1
18
10
12
14
15
11 13
21
17
20
16
18
21
Fig. 10
IM-P135-14 ST Issue 2
19
6. Maintenance
Note: Before actioning any maintenance programme
observe the 'Safety information' in Section 1.
6.2 Maintenance
CAUTION: Use caution when removing the cover and gasket. The gasket contains thin
stainless steel reinforcement that may cause cuts to the skin. Care should be taken to
prevent personal injury from the strong snapping action.
6.2.1 Break and disconnect all connections to the cover. Remove the cover bolts and lift the
cover and mechanism assembly from the body, noting the cover orientation ('V' notch) Reference Figs 12 - 14 to visually see how to remove the cover and mechanism assembly.
6.2.2
Visually inspect the mechanism to verify that it is free of dirt and scale and that the float
and mechanism moves freely. Note: Each mechanism assembly is factory set and
tested. No adjustment to the mechanism should be made. If the mechanism assembly
does not function correctly the entire mechanism should be returned to Spirax Sarco for
replacement under the warranty terms.
6.2.3 To re-assemble, reverse the above procedure noting the following points:
a. When installing the cover and mechanism in tight spaces the mechanism should
be held horizontally as shown in Figure 12.
b. The float should be inserted into the pump body first, carefully ensuring the cycle
counter probe and paddle do not clash with the body, per Figure 13. Special
attention must be made when fitting the cover and mechanism assembly. Do
not knock the mechanism against the body or similarly hard object as this
may dislodge the pivots and can permanently affect the pumps performance.
c. As the mechanism is inserted into the pump body the mechanism should be held
vertically and gently lowered to its final resting positon. The cover must be orientated
so that the 'V' cast into the pump cover lines up with the body vertical line on the
outside diameter of the mating flange located on Figure 11. This ensures correct float
orientation - See Figure 14.
6.2.4 Assemble the cover bolts and torque to 210 to 238 N m (155 to 175 lbf ft) in a cross
pattern as shown in Figure 11.
8
1
4
5
6
3
2
7
Fig. 11
Cover 'V'
20
IM-P135-14 ST Issue 2
Fig. 12
Fig. 13
Fig. 14
IM-P135-14 ST Issue 2
21
7. Fault finding
Note: Before actioning any maintenance programme
observe the 'Safety information' in Section 1.
If a correctly sized PTF4 pressure powered pump does not operate properly, an incorrect
hook-up is suspect in new installations. For existing installations where the pump operates
occasionally or not at all, the cause is often a change in the system supply or backpressure
conditions beyond the original design parameters. With the system conditions and problem
symptoms determined, check the following in turn and correct as necessary.
Symptom
Cause
1.a) Motive supply closed.
b) Condensate inlet line closed.
c) Condensate discharge line closed.
d) Motive pressure insufficient to overcome
backpressure.
1
e) Check valves(s) installed in wrong
direction.
f) Pump air-locked.
Pump fails to operate on start-up.
g) Vent assist valve not closing on start-up.
2
Supply line / equipment flooded, but the
pump appears to cycle normally
(periodic audible exhaust observed).
Remove the check valve and visually
inspect, body and plate faces, hinge and
spring.
22
2.a) Pump undersized.
b) Insufficient filling head.
c) Insufficient motive pressure to achieve
rated capacity.
d) Restriction in condensate inlet line.
e) Inlet check valve stuck open (debris).
IM-P135-14 ST Issue 2
Check and Cure
1.a) Open valve(s) to supply motive pressure to pump.
b) Open all valves to allow condensate to reach pump.
c) Open all valves to allow free discharge from pump to destination.
d) Check motive pressure and static backpressure. Adjust motive pressure to 1 to 1.3 bar g
(15 - 20 psi g) higher than static backpressure.
e) Verify proper flow direction is correct.
f) On a vented system, ensure that the vent line is unrestricted to atmosphere and selfdraining to the pump or receiver. On a closed system, isolate the pump from the
pressurised space being drained. (Exhaust tie-back line closed.) Break the exhaust
connection at the pump cover. Keep personnel clear of the exhaust connection. If the
pump begins to cycle, air locking has occurred. Recheck that the exhaust tie-back is in
accordance with the installation instructions. Install a thermostatic air vent at a high point
in the exhaust line. Ensure that the equalizer line is self-draining.
g) Close the isolation valve fitted in the exhaust line above the vent assist valve, closing the
vent assist valve discharge but still allowing the exhaust valve to discharge fully. Allow
hot condensate to reach the pump and then re-open the isolation valve above the vent
assist valve.
2.a) Verify capacity rate - See TI-P135-13. Increase the check valve size or install an
additional pump as required.
b) Verify filling head - See Section 2.3. Lower the pump to achieve the required filling head.
c) Check motive pressure setting and maximum backpressure during operation. Compare
with the capacity table - See TI-P135-13. Increase the motive pressure as required to
meet load conditions.
d) Verify that fully ported fittings are used. Blowdown the strainer, if fitted. Check that all valves
are fully open.
e) Isolate the inlet check valve and relieve line pressure. Clean seating surfaces and reinstall
or replace, if necessary.
IM-P135-14 ST Issue 2
23
Symptom
Cause
3.a) Discharge line closed or blocked.
3
Supply line / equipment flooded, and the
pump has stopped cycling (audible
periodic exhaust not observed).
Important safety note:
For steps (d) through (g) it is necessary to
break the exhaust / tie-back line at the
pump exhaust connection. On closed loop
systems, care should be exercised to
ensure that the pump is isolated (motive
supply, condensate inlet and discharge,
and exhaust / tie-back line all closed) and
that case pressure is relieved prior to
breaking this connection to avoid injury to
personnel. Also, under fault conditions, it is
possible that hot condensate may run out
of the exhaust connection when broken for
both closed loop and vented systems. This
possibility should be taken into
consideration when performing these steps
to avoid scalding of personnel or water
damage to nearby equipment.
4
Chattering or banging in the return main
after the pump discharges.
24
b) Discharge check valve stuck closed.
c) Insufficient motive pressure.
d) Motive inlet valve leaking and / or worn.
e) Mechanism faults:
i) Broken spring.
ii) Ruptured float.
f) Exhaust / tie-back causing vapour lock
(vented or closed loop).
g) Inlet check valve stuck closed.
4.a) Vacuum created at the pump outlet after
discharge because of acceleration /
deceleration of large water slug(s) in the
return main (usually results from long
horizontal run with multiple rises and
drops).
b) Pump 'blow-by'.
IM-P135-14 ST Issue 2
Check and Cure
3.a) Check the motive pressure and static backpressure (at pump discharge). If equal, a closed
or blocked discharge line is suspected. Check all valves downstream of the pump to ensure
that the discharge is not obstructed.
b) After checking per 3(a), isolate the discharge check valve and safely relieve line pressure.
Remove the check valve and visually inspect the body and plate faces, hinge and spring.
Clean the seating surfaces and reinstall or replace, if necessary.­
c) If the motive pressure is below the static backpressure, increase the motive pressure
setting to 1 to 1.3 bar g (15 - 20 psi g) above the static backpressure. Do not exceed the
rated pressure limits of the equipment.
d) Slowly open the motive supply line, leaving the condensate inlet and discharge lines closed.
Observe the exhaust connection for steam or air leakage. If leakage is observed, an inlet valve
problem is indicated. Isolate the pump, and safely relieve pressure, remove the cover and
mechanism assembly and visually inspect. Replace inlet valve and seat assembly.
e) With the motive line open, slowly open the condensate inlet line to the pump, allowing the pump
to fill and observe the exhaust connection. Keep personnel clear of exhaust! If condensate
runs out of the exhaust connection, a mechanism fault is clearly indicated. Isolate the pump by
shutting off the motive supply and condensate inlet, and safely relieve the pressure, remove the
cover and mechanism assembly, and visually inspect. Examine the springs and float for obvious
defects. Also check the stroke mechanism for any source of binding or increased friction. Repair
and / or replace all defects observed.
f) If the mechanism is heard to trip and no fluid is observed running out the exhaust connection,
slowly open the discharge line from the pump and observe operation. Keep personnel clear of
exhaust connection! If the pump cycles normally, a fault in the exhaust / tie-back line is
suspected. Recheck the exhaust / tie-back piping layout for compliance with the installation
instructions. Exhaust / tie-back line must be self-draining to prevent vapour locking the pump.
g) If the mechanism is not heard to trip and fluid is not observed running from the exhaust
connection, it is suspected that the fault lies in the condensate inlet piping. Ensure that all
valves leading to the pump have been opened. If so, this indicates that the inlet valve is
stuck closed. Isolate the pump and check the valve and relieve line pressure. Visually
inspect the head, seat and stem. Clean seating surfaces and reinstall or replace, if
necessary. Reinstall exhaust / tie-back connection and open the line.
4.a) Install a vacuum breaker at the top of the lift (at a high point in the return line). For
pressurised return systems an air eliminator may be required downstream of the vacuum
breaker - See Figure 15, page 27.
b) Check the condensate inlet pressure and static backpressure at the pump discharge. If the
inlet pressure equals or exceeds the static backpressure, a 'blow through' problem is
suspected. On vented systems, check for leaking traps discharging into the condensate inlet
line which would increase inlet line pressure. Replace any faulty traps. On closed loop
systems, if condensate inlet pressure can exceed static backpressure under normal operation
(i.e. boost in equipment operating pressure via a modulating control valve or significant
decrease in static return main pressure), a pump-trap combination is required. The pumptrap combination will prevent passage of steam into the return main and allow the pump to
cycle normally when condensate is present - See Figures 5, 6 and 7, pages 14 and 15.
IM-P135-14 ST Issue 2
25
Symptom
Cause
5.a) Faulty steam traps are discharging live
steam into the condensate inlet line (See
also 4(b), Pump 'blow-by').
5
b) Excessive (over 110 kg / h, 50 lb / h) flash
steam is being vented through the pump.
c) Exhaust valve stuck or worn.
Vent line discharging excessive flash
steam (vented applications only).
d) Vent assist valve not closing.
Other typical hook-up drawings
The hook-up drawings illustrated on pages 27 to 31, do not necessarily represent
recommended arrangements for specific service conditions; but rather serve only to
illustrate the variety of applications where the pressure-powered pump can be utilized.
Design requirements for each application should be evaluated for the best condensate
recovery arrangement tailored to your specific needs.
For use of the pressure-powered pump in hook-ups other than those described previously,
and for any additional information you may require, contact Spirax Sarco.
26
IM-P135-14 ST Issue 2
Check and Cure
5.a) Check for leaking traps discharging into the condensate return. Repair or replace faulty
traps (See also 4(b), Pump 'blow-by').
b) Vent the receiver ahead of the pump.
c) Isolate the pump and safely relieve the pressure, and remove the cover and mechanism
assembly. Remove the exhaust head and seat assembly. Visually inspect the seating
surface. Clean and reinstall or replace, if worn.
d) Close the isolation valve fitted in the exhaust line above the vent assist valve, closing the
vent assist valve discharge but still allowing the exhaust valve to discharge fully. If the
discharge stops and the pumping capacity is still acceptable leave as is. If by closing the
vent assist valve the capacity is no longer acceptable replace the vent assist valve.
Float operated air vent
Reservoir
PTF4
Non-electric pressure powered pump
Fig. 15 Pressure-powered pump discharging to a long delivery line
(An air eliminator is needed with a seal in the piping)
IM-P135-14 ST Issue 2
27
*H - Total lift or backpressure is the height (H) in feet x 0.433 plus psi g in the return line,
plus downstream piping friction presure drop in psiI calculated at a flowrate of the lesser of
the 6 times the actual condensate flowrate.
Total
lift
*H
TD
'Y' type
strainer
PTF4
Check valve
'Y' type strainer
Check valve
Fig. 16 Pressure-powered pump draining water from a sump pit
28
IM-P135-14 ST Issue 2
LP
flash
steam
HP condensate
and flash steam
Exhaust steam
vented to
LP system
Flash
recovery
vessel
Backpressure
greater
than LP
flash
pressure
'Y' type
strainer
TD
Condensate
PTF4
Check valve
Check valve
Fig. 17 Flash steam recovery at pressure above or below atmospheric
IM-P135-14 ST Issue 2
29
25 mm (1") equalizer Line
Total lift
H
Vacuum
space
Return
main
Steam
supply
P
Filling
head
'Y' type strainer
'Y' type
strainer
Alternate
discharge
connection
TD
PTF4
Non-electric
pressure-powered
pump
Pipe to
drain
Fig. 18 Draining condensate from a vacuum space to return main
30
IM-P135-14 ST Issue 2
Arrangement of small steam / liquid heat exchanger where steam space pressure may
fall below the backpresure.
Steam
supply
Flow
'Y' type
strainer
Vacuum
breaker
Vent to atmosphere. The vent must be
piped to a safe location such that there
is no risk to personnel. The use of a VHT
vent head is recommeded if it can not be
piped to a pit or similar location.
Temperature
control
and
sensor
Air vent
Heater
'Y' type
strainer
Return
Centrifugal pump
FT steam trap
H
Spiratec
steam trap loss
detector
Vent
Multiple loads
connected to
vented receiver
Head 'H' must be enough to give
trap capacity needed when steam
space pressure falls to zero.
PTF4
Fig. 19 Draining a small heat exchanger and other loads to a pressure-powered pump
IM-P135-14 ST Issue 2
31
32
IM-P135-14 ST Issue 2
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