Pressure Powered Pump™ PPEC

Pressure Powered Pump™ PPEC
INSTALLATION AND MAINTENANCE INSTRUCTIONS
IM-5-200-US
October 2015
Pressure Powered Pump™ PPEC
Safe operation of these products can be guaranteed only if they are properly installed, commissioned, used and maintained by qualified personnel (see point 11 on this document) 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.
1.5 Hazardous environment around the product
1. Intended use
Referring to the Installation and Maintenance Instructions,
Nameplate and Technical Information Sheet, check that the product is suitable for the intended use/application. The products listed
below comply with the requirements of the European Pressure
Equipment Directive 97/23/EC and carry the CE when so required.
The products fall within the following Pressure Equipment Directive
categories:
Product
PPEC I)
II)
Group 2 Gases
Iron
Steel
N/A
II
The products have been specifically designed for use on
steam, air and inert industrial gases which 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.
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.
Remove protective covers from all connections before
installation.
V)
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.
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.
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
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').
1.14Freezing
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
1.15Disposal
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.
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
2
Gradient
1:100
Trap set
Condensate
Steam
Trap set
Condensate
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
Guides
Small
lateral
movement
Large
lateral
movement
Operating Pressure Range 5 to 125 psi (.34 to 8.6 bar)
How Pressure Powered Pump™ Operates
1. In the normal position before start-up the float (5) is at its lowest position with the steam valve (6) closed and exhaust valve
(7) open.
2. When liquid flows by gravity through inlet check valve (8) into
pump body, the float (5) will become buoyant and rise.
3. As the float (5) continues to rise the mechanism link (3) is
engaged which increases the tension in the springs (15). When
the float (5) has risen to its upper tripping position the energy
in the springs is released instantaneously causing the linkage
mechanism (3) to snap upwards over center moving push rod
upwards to simultaneously open steam inlet valve and close
exhaust valve.
4. Steam will now flow through the steam valve (6) and develop a
pressure within the body forcing the liquid out through the dis-
PPEC
Operating Pressure
Inlet (Front Face)
charge check valve (9). The inlet check valve (8) will be closed
during the discharge cycle.
5. As the liquid level in the pump body decreases so does the
float’s position. Before the float reaches its lowest position the
mechanism link (3) is engaged increasing the tension in the
springs (15). When the float is at its lower tripping position in
the body the energy in the springs is released instantaneously
causing the linkage mechanism (3) to snap over center downward moving push rod down causing the steam valve (6) to
close and exhaust valve to open simultaneously.
6. Liquid will again flow through inlet check valve (8) to fill pump
body and the cycle will be repeated.
6
Exhaust
Outlet
1A
1
3
15
0.100”
7
12
13
9
Liquid
Outlet
5
8
8
Liquid
Inlet
3
10
Installation — Vented Systems (Fig. 2)
Check valve
to help reduce
likelihood of
backflow and
waterhammer.
Operating Steam
or Gas Supply
Vent to atmosphere. Vent to be piped to a
safe location such that there is no risk to
personnel. Vent head recommeded if vent
not piped to a pit or similar location.
Pump
Exhaust
Condensate
Return
Line
Condensate
Vented
Receiver
H
Height
Filling
Head
6”
Preferred
At least
12” Seal
on overflow. Discharge to
be piped to safe location
such that there is no risk to
personnel.
Inlet
Strainer
TD 42L or 52L Trap
When steam supply
is used
Figure 2
Recommended installation of pressure powered pump when fitted with a reservoir or vented receiver. In an “open” system flash steam must be vented or condensed ahead of pump inlet.
Application details will dictate which of the following options will be necessary to accomplish this.
Caution: Before installation or any maintenance is performed, ensure that all condensate, steam, air or gas lines
are closed to prevent personnel injury.
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 — Overflow piping must be used on a
vented system. Over-flow 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 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 over-flow, can occur for many reasons. These including,
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.
Over-flows will normally be a minimum of 1 1/2 “ (DN40) in
diameter, but may need to be larger for high capacity units such
as packaged PTF4, or where the length of over flow pipe run,
between receiver and discharge point, is more than 2 meters (6
ft.). 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 zero to 5000 l/hr. (zero to 11000 lb. /hr.)
use 1½”
Condensate loads from 5000 I/hr.to 10000 I/hr. (11000 to 22000 lb.
/hr.) use 2”
Condensate loads from 10000 to 18000 I/hr. (22000 to 39600 lb. /
hr.) use 3”
Normally over-flow connections will be fitted with a “loop seal”
arrangement or a suitably sized float trap, to prevent steam
escaping via the over-flow connection.
1.Install the pump physically below the receiver to be
drained with the exhaust connection (10) vertically
upwards. 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
Fig. 2.For other filling head variations, see the capacity
table on TI-5-202-US.
Recommended Filling Head:
3/4” & 1” PPEC
6”
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 proper receiver sizing, refer to the table shown
below. All inlet line fittings must be fully ported.
4
Vented 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. The chart below shows
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 below,
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.
If desired, receiver overflow piping can be installed as
shown in Fig. 2 and piped to a suitable drain. The piping must form a loop type water seal at least 12” deep
immediately after the receiver.
Pump Size
Flash Steam
Up to
75 pph
150 pph
300 pph
600 pph
900 pph
5
Receiver
Vent Line
DiameterLength Diameter
3”
30”
1-1/2”
4”
30”
2”
6”
36”
2-1/2”
8”
36”
3”
10”
36”
4’
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 piping runs immediately ahead of the inlet check
valve and after the discharge check valve should be
kept to a minimum. Connect the discharge to the return
main or other installation point.
Note:To achieve rated capacity, pump must be installed
with check valves as supplied by Spirax Sarco,Inc.,
except, at inlet on sump pit application as shown in Fig.
9.
4. Connect the operating medium (steam, air or gas) supply to the motive 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 trap discharge
should be piped into the receiver ahead of the pump for
steam systems.
Note:When available motive pressure exceeds 125
psi, 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 back pressure
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.
5.Exhaust line should be piped, unrestricted, to atmosphere. Line should be vertical, if possible. If horizontal
runs must be used, line should be pitched so that it is
self draining to the pump or receiver.
Installation — Closed Loop Systems (Figs. 3 or 4)
A closed-loop installation is one in which the exhaust line
of the pump is piped back (pressure equalized) to the
steam space being drained.
Caution:Before installation or any maintenance is performed, ensure that all steam, condensate, air or gas lines
are closed to prevent personnel injury.
1. Install the pump physically below the equipment being
drained with the exhaust connection (10) vertically
upwards. 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 Fig. 3. For other filling head variations, see
Capacity Table on TIS 5.202.
Recommended Filling Head:
3/4” & 1” PPEC
6”
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 Fig.
3. For proper reservoir sizing, refer to “Inlet Reservoir
Piping” table shown on this page. 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. Connect the check valves (8) and (9) to the pump, making sure that the flow through the valves is in the proper
direction. For best performance, horizontal piping runs
immediately ahead of the inlet check valve and after the
discharge check valve should be kept to a minimum.
Connect the discharge to the return main or other
installation point.
Note: To achieve rated capacity, pump must be installed
with check valves as supplied by Spirax Sarco, Inc.
4.Connect the operating medium (steam only) supply to the motive supply inlet in the cover. 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 (Nonflooded).
Note:When available motive pressure exceeds 125
psi, 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 desired capacity. A safety relief valve should be
installed at the connection provided in the pump cover
or in the motive steam supply piping.
5. Exhaust line must be piped, unrestricted, to the steam
space being drained. The exhaust line can be connected to the top of the reservoir pipe when a proper connection in the steam space is not available. 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 exhaust line should be
pitched so that the line is self-draining.
6.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 4.
Inlet Reservoir Piping
To drain condensate from a single piece of equipment
in a “closed 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. The chart below shows 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. Feet of
reservoir piping needed for...
Pump Size
Liquid
P
ipe Size
Lb. per Hr.
1-1/2”2”3”4”6”
500 or less
2’
10003’ 2’
15005’ 3’
2000
6’4’2’
3000 6’ 3’
4000 8’ 3.5’2’
5000 10’ 4.5’2.5’
6000 5.5’3’
7000 6’ 3.5’
8000 7’ 4’
P1
Return Line
Balanced
Pressure
Thermostatic
Air Vent
Pilot Operated
Temperature
Control Valve
1/2” HP Steam
Supply
Heat Exchanger
Reservoir
Filling
Head
Spira-tec
Steam Trap
Loss Detector
Pressure
Powered
Pump
Draining L.P. Heat Exchanger to
Overhead Return. Pressure at PP
Pump outlet P2 exceeds pressure
of supply to Heat Exchanger P1.
P2
Thermo-Dynamic®
Trap
Figure 3
6
Startup Procedure
(All Hookups)
P1
Balanced
Pressure
Thermostatic
Air Vent
Steam
Supply
Wye Strainer
Pilot Operated
Temperature Control Valve
Temperature
Control Sensor
Return
Flow
Heater
Centrifugal
Pump
Reservoir Pipe
Steam
Supply
Pressure
Powered
Pump
Figure 4
Draining L.P. Heat Exchanger to
Overhead Return. Pressure at PP Pump
outlet P2 does not exceed pressure of
supply to Heat Exchanger P1.
P2
1. Slowly open supply (steam, air or gas) to provide
pressure at the PP Pump inlet valve. Check that
trap/drainer on motive line is operational.
2. Open gate valves in the PP Pump inlet and discharge lines.
3. Open valve(s) ahead of unit allowing condensate
to enter the receiver/reservoir and fill the PP
Pump body. Pump will discharge when full.
4. Observe operation for any abnormalities. PP
Pump(s) should cycle periodically with an audible
exhaust at the end of the pumping cycle. If any
irregularities are observed, recheck installation
instructions for proper hookup. Consult factory if
necessary.
5. If overflow piping has been provided, check that
a water seal has been established to prevent any
steam from being vented during normal operation. Prime overflow piping if necessary.
Float & Thermostatic
Steam Trap
Maintenance: Inspection & Repairs
CAUTION:
Before removing the cover and mechanism assembly, be sure that
the pump is completely isolated and relieved of any internal pressure. Motive supply, exhaust/tie-back, condensate inlet, and discharge lines should all be closed prior to performing any work on
the pump. Use caution when removing cover and gasket. Gasket
contains thin stainless steel reinforcement that may cause cuts to
the skin.
1.Break all connections to the cover. Remove cover bolts and lift
the cover and mechanism assembly from the body, noting the
cover orientation.
2.Visually inspect the mechanism to verify that it is free of dirt
and scale and moves freely.
3.Visually check springs (15). If defective, remove retaining clips
and slide spring from pins. Replace with new springs (if necessary) and install retaining clips.
4.To check inlet and exhaust valves:
a.Remove the mechanism casting securing bolts (13). Carefully
lift mechanism assembly free from cover.
NOTE:
Mechanism assembly is factory set and tested. No adjustments to the
mechanism assembly should be made. If required, entire cover and
mechanism assembly should be returned to the factory for repair service.
Inlet
Seat
85-90
ft-lb
7
Exhaust
Seat
85-90
ft-lb
b.Visually inspect seating surfaces of inlet and exhaust valves
for signs of wear (inlet valve assembly must be removed to
check seat). Clean seating areas and reinstall or replace if
necessary. When replacing steam or exhaust valve heads
or seats, make certain the actuator disc (12) is adjusted as
shown in drawing on page one. Torque seats as shown in
table below. The float must be in the down position when
making this adjustment.
c.To reassemble, reverse the above procedure. Replace gaskets.
5.When reinstalling cover and mechanism assembly, cover
should be oriented as noted (1) above. Follow the start-up procedure to bring the pump back in operation. Torque cover bolts
as shown on previous page.
For use of these units in hookups other than those described and
illustrated, and for any additional information you may require,
contact Spirax Sarco Applications Engineering Department, toll
free: 1-800-833-3246
PPEC
Cover Bolts
175-185
ft-lbs
Pressure Powered Pump™ Troubleshooting Checklist
If a correctly sized Pressure Powered Pump does not
operate properly, an incorrect hookup 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 back pressure conditions
beyond the original design parameters. With the system
conditions and problem symptoms determined, check the
following in turn and correct as necessary.
Symptom
1.Pump fails to operate on startup.
Check and Cure
1.a) Open valve(s) to supply motive
pressure to pump.
b) Open all valves to allow condensate to reach pump.
b) Condensate inlet line closed.
c) Condensate discharge line closed. c) Open all valves to allow free discharge from pump to
destination.
d) Check motive pressure and static backpressure.
d) Motive pressure insufficient to
Adjust motive pressure to 10-15 psi higher than static
overcome backpressure.
backpressure.
e) Check valves(s) installed in wrong e) Verify proper flow direction and correct, if required.
direction.
f) On vented system, assure that vent line is unrestrictf) Pump air-locked.
ed to atmosphere and self-draining to the pump or
receiver. On a closed system, isolate the pump from
the pressurized space being drained. (Exhaust tieback line closed.) Break exhaust connection at pump
cover. Keep personnel clear of exhaust connection.
If pump begins to cycle, air locking has occurred.
Recheck that exhaust tie-back is in accordance with
the installation instructions. Install a thermostatic air
vent at a high point in the exhaust line. Assure that
the equalizer line is self-draining.
1.a) Motive supply closed.
2.a) Verify rate capacity per TIS 5.202 capacity table.
Increase check valve size or install additional pump as
required.
b) Verify required filling head per TIS 5.202. Lower pump
b) Insufficient filling head.
to achieve required filling head.
c) Check motive pressure setting and maximum backc) Insufficient motive pressure to
pressure during operation. Compare to capacity table
achieve rated capacity.
of TIS 5.202. Increase motive pressure as required to
meet load conditions.
d) Restriction in condensate inlet line. d) Verify that fully ported fittings are used. Blowdown the
strainer, if fitted. Check that all valves are fully open.
e) Isolate inlet check valve and relieve line pressure.
e) Inlet check valve stuck open
Remove cap an visually inspect head, seat, and stem.
(debris).
Clean seating surfaces and reinstall or replace, if necessary.
2.a) Pump undersized.
3.Supply line/equipment flooded, and
pump has stopped cycling (audible
periodic exhaust not observed).
Installation and troubleshooting should be performed by
qualified service personnel. Before breaking any connections of the pump or piping system every effort should be
made to assure that internal pressure has been relieved
and that 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 pressure, this fact will be apparent before
completely removing the pipe or component. Always
relieve pressure before breaking any joint.
Cause
2.Supply line/equipment flooded, but
pump appears to cycle normally
(periodic audible exhaust observed).
CAUTION:
3.a) Discharge line closed or blocked.
b) Discharge check valve stuck
closed.
c) Insufficient motive pressure.
3.a) Check motive pressure and static back-pressure (at
pump discharge). If equal, a closed or blocked discharge line is suspected. Check all valves downstream
of pump to assure an unobstructed discharge.
b) After checking per 3(a), isolate discharge check valve
and relieve line pressure. Visually inspect head, seat
and stem. Clean seating surfaces and reinstall or
replace, if necessary.­
c) If motive pressure is below static backpressure,
increase motive pressure setting to 10-15 psig above
static backpressure. Do not exceed rated pressure
limits of equipment.
For steps 3(d) through 3(g) on page 7—With exhaust/
tie-back line isolated from the equipment being
drained (close-loop systems), break the exhaust/tieback connection at the pump cover and—
8
Symptom
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 assure 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.
Cause
d) Motive inlet valve leaking and/or
worn.
e)
Mechanism Faults
i) Broken springs
ii) Ruptured float
iii) Mechanism binding
f) Exhaust/tie-back causing vapor
lock (vented or closed loop).
g) Inlet check valve stuck closed.
4.Chattering or banging in return main
after pump discharges.
5.Vent line discharging excessive flash
steam (vented applications only).
9
4.a) Vacuum created at pump outlet
after discharge because of acceleration/deceleration of large water
slug in return main (usually results
from long horizontal run with multiple rises and drops).
b) Pump “blow-by”.
Check and Cure
d) Slowly open 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 pump, remove cover and mechanism assembly and visually inspect. Replace inlet valve and seat
assembly.
e) With motive line open, slowly open condensate inlet
line to the pump, allowing pump to fill and observe
exhaust connection. Keep personnel clear of
exhaust! If condensate runs out exhaust connection, a mechanism fault is clearly indicated. Isolate
pump by shutting off motive supply and condensate
inlet, remove cover and mechanism assembly, and
visually inspect. Examine springs and float for obvious defects. Stroke mechanism and check for any
source of binding or increased friction. Repair and/
or replace all defects observed.
f) If 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
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 vapor locking the pump.
g) If 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. Assure 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
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 line.
4.a) Install a vacuum breaker at the top of the lift (at high
point in return line). For pressurized return systems
and air eliminator may be required downstream of
the vacuum breaker. (See Fig. 8).
b) Check 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
pump trap combination will prevent passage of steam
into the return main and allow the pump to cycle normally when condensate is present (See Fig. 4)
5.a) Faulty steam traps discharging live 5.a) Check for leaking traps discharging into condensate
return. Repair or replace faulty traps. (See also 4(b),
steam into condensate inlet line
Pump “Blow-By”).
(See also 4(b), Pump “Blow-By”).
b) Excessive (over 50 lb/hr) flash
b) Vent receiver ahead of pump.
steam being vented through pump.
c) Exhaust valve stuck or worn.
c) Isolate pump and remove cover and mechanism
assembly. Remove exhaust head and seat assembly. Visually inspect seating surface. Clean and reinstall or replace, if worn.
Other Typical Hook-up Sketches
FloatOperated
Air Vent
Reservoir
Figure 8
Pressure Powered Pump
Discharging to Long Delivery Line
(Air Eliminator needed with seal in piping)
The hook-up sketches shown 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
Applications Engineering Department, toll free:
1-800-833-3246
Non-Electric
Pressure Powered Pump
†H - Total lift or back pressure is the height (H) in feet
x 0.433 plus PSIG in return line, plus downstream piping friction presure drop in PSI calculated at a flow
rate of the lesser of the 6 times the actual condensate
flowrate.
LP
Flash
Steam
Exhaust Steam
Vented to
LP System
Total Lift
†H
Flash Recovery
Vessel
HP Condensate
& Flash Steam
Thermo-Dynamic
Steam Trap
Figure 9
Wye Strainer
Condensate
Wye
Strainer
Non-Electric
Pressure
Powered
Pump
Figure 10
Non-Electric
Pressure
Powered Pump
Wye
Strainer
Thermo-Dynamic
Steam Trap
Flash Steam Recovery
at Pressure Above or
Below Atmospheric
Pressure Powered
Pump Draining Water
from Sump Pit
Back
Pressure
Great
Than LP
Flash
Pressure
15” Swing Check
Wye
Strainer
Steam
Supply
1” Equalizer Line
Return
Main
Vacuum
Space
Vacuum
Breaker
Air Vent
Self Acting
Temperature
Control
Flow
Arrangement of Small Steam/
Liquid Heat Exchanger where
steam space pressure may fall
below back presure.
Temperature
Control
Sensor
Steam
Supply
Heater
Total Lift
H
P
Filling Head
Alternate
Discharge
Connection
Return
Wye
Strainer
Centrifugal Pump
Wye
Strainer
ThermoDynamic
Steam Trap
Pipe to Drain
Non-Electric
Pressure
Powered Pump
Head “H” must be enough to give trap
capacity needed when steam space
pressure falls to zero.
Pipe to
Drain
Figure 11 - Draining Condensate from Vacuum Space to Return Main
10
Figure 12
Draining Small Heat
Exchanger and Other Loads
to Pressure Powered Pump
Spira-tec Steam Trap
Loss Detector
Vent
Float & Thermostatic
Steam Trap
Multiple Loads
Connected to
Vented Receiver
Non-Electric
Pressure
Powered Pump
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
11
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