BOWMAN EC Series Owner's manual

Heat Exchanger Technology by
Installation, Operation
& Maintenance Guide
HYDRAULIC OIL COOLERS
BOWMAN®
100 YEARS OF HEAT TRANSFER TECHNOLOGY

Thank you for purchasing a high quality Bowman hydraulic oil cooler.
Bowman® has been manufacturing hydraulic oil coolers for over 60 years and our products are
renowned for their quality, heat transfer performance and durability.
Please read this‘Installation, Operation & Maintenance Guide’ carefully before installation to
ensure your hydraulic oil cooler operates eciently and reliably.
Please keep this guide for future reference to ensure the long term performance of you
Bowman hydraulic oil cooler.
Should you require advice or assistance, please contact your Bowman stockist or distributor.
Further copies of this ‘Installation, Operation & Maintenance Guide’ can be downloaded from
our web site www.ej-bowman.com
Introduction
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Contents
Introduction 2
1. Safety
1.1 Hazards when handling
the oil cooler 3
1.2 Safety instructions 3
1.3 Approved use 3
1.4 Potential hazards 4
2. Installation
2.1 Transport / storage 4
2.2 Fitting 4
2.3 Connecting the cooler 5
2.4 Marine installation
recommendations 6
2.5 Orice plates 6
2.6 Composite end
cover torque gures 6
3. Operation
3.1 Maximum ow rates 7
3.2 General information 7
4. Commissioning 8
5. Maintenance / Repair
5.1 Winter shut-down in
areas exposed to frost 8
5.2 General Maintenance 9
5.3 Cleaning 9
5.4 End cover bolt
tightening sequence 9
6. Potential Service Issues 10
6.1 Tube failures 10
6.2 Fault nding 10
7. Warranty 11
8. Spare Parts 11
9. CE Marking Documentation11
10. Notes on zinc anodes 11
BOWMAN® Hydraulic Oil Coolers are only approved for cooling hydraulic oil.
Any other use unless sanctioned by BOWMAN® is not approved.
BOWMAN® declines all liability for damage associated or arising from such use:
The maximum permissible operating pressure must not exceed:
Oil side: 20 bar max.
Water side: 16 bar max.
Applies to EC-RK three pass threaded connections only – for other versions
please contact BOWMAN® for guidance.

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4. Commissioning 8
5. Maintenance / Repair
5.1 Winter shut-down in
areas exposed to frost 8
5.2 General Maintenance 9
5.3 Cleaning 9
5.4 End cover bolt
tightening sequence 9
6. Potential Service Issues 10
6.1 Tube failures 10
6.2 Fault nding 10
7. Warranty 11
8. Spare Parts 11
9. CE Marking Documentation11
10. Notes on zinc anodes 11
BOWMAN® Hydraulic Oil Coolers are constructed to current practice and recognised safety
standards. Hazards may still arise from operation, such as:
•Injury of the operator or
•Third parties or
•Damage to the oil cooler or
•Damage to property and equipment
Any person involved with the installation, commissioning, operation, maintenance or
repair of the cooler must be:
•Physically and mentally capable of performing such work
•Appropriately qualied
•Comply completely with the installation instructions
The oil cooler must only be used for its intended purpose.
In the event of breakdowns which may compromise safety, a qualied person must always be contacted.
1.2 Safety Instructions
The following symbols are used in these operating instructions:
This symbol indicates an immediate danger to health.
Failure to comply with this instruction may result in severe injury.
This symbol indicates a possible danger to health.
Failure to comply with this instruction may result in severe injury.
This symbol indicates a possible risk to health.
Failure to comply with this instruction may result in injury or damage to property.
This symbol indicates important information about correct handling of the equipment
Failure to comply with this instruction may cause damage to the heat exchanger
and/or its surroundings.
1.3 Approved use
1. Safety
1.1 Hazards When Handling the oil cooler
BOWMAN® Hydraulic Oil Coolers are only approved for cooling hydraulic oil.
Any other use unless sanctioned by BOWMAN® is not approved.
BOWMAN® declines all liability for damage associated or arising from such use:
The maximum permissible operating pressure must not exceed:
Oil side: 20 bar max.
Water side: 16 bar max.
Applies to EC-RK three pass threaded connections only – for other versions
please contact BOWMAN® for guidance.
Danger
Caution
Take Care

Ensure the maximum permissible operating pressures are not exceeded.
NB: Before the oil cooler is disconnected it must be allowed to cool and
be depressurized. The supply and return from the cooler should
be isolated to minimise uid loss.
2. Installation
2.1 Transport / storage
The oil cooler must be drained prior to transportation. Once drained
and dry, the oil cooler must only be stored indoors in a non-aggressive
atmosphere. The connections should be capped to avoid ingress of dirt and
contaminants.
2.2 Fitting
Before tting, the cooler should be checked for visible signs of damage. The
oil cooler should be connected in counterow so that the uids ow in opposite
directions, as shown in the illustration below:
1.4 Potential Hazards
Take Care
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The maximum permissible operating temperature must not exceed:
Oil side: 120º C
Cooling Water side: 110ºC
Variants with higher temperature and pressure ratings are available. Please
contact the Sales for further details
Caution
Take Care
Multiple units can be connected in parallel.

Shut o all drainage valves in the ow and return pipes in both circuits.
When tting the oil cooler into the pipe work care must be taken to ensure that no debris
has been introduced into the oil cooler.
Unsupported lengths of pipework should be avoided so as not to subject the oil cooler
to excessive loads.
Water side pipework diameter should not reduce to less than the connection size within a
distance of 1m from the oil cooler.
Measures should be taken to isolate the oil cooler from excessive vibration.
Taper ttings are not recommended as these can split the shell and end cover castings if over
tightened.
The correct length of tting should be used as too long a tting will damage the tubestack.
Pipework materials must be compatible with the oil cooler materials. Stainless steel sea water
pipes and ttings should not be used adjacent to the oil cooler.
If the sea water supply is taken from a ships main, ensure that the recommended ow rate
cannot be exceeded. This will normally mean that an orice plate must be tted in the pipe
work at least 1m before the cooler with the orice size calculated to ensure that the maximum
sea water ow rate cannot be exceeded. If these precautions are not taken, it is possible that the
sea water ow rate through the cooler may be several times the recommended maximum
which will lead to rapid failure.
2.3 Connecting the oil cooler
Take Care
Or in series:
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2.4 Marine installation, recommendations
No oil cooler manufacturer can guarantee that their products will have an
indenite life and for this reason, we suggest that the cooling system is
designed to minimise any damage caused by a leaking oil cooler. This can be
achieved as follows:
1. The oil pressure should be higher than the sea water pressure, so that in
the event of a leak occurring, the oil will not be contaminated.
2. When the hydraulic system is not being used, the coolers should be
isolated from sea water pressure.
3. The sea water outlet pipe from the cooler should have a free run to waste.
4. Stainless steel sea water pipes and ttings should not be used adjacent to
the oil cooler.
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5. Important note for marine applications: during commisioning, shutdown
and standby periods, if the oil cooler has not been used over 4-6 day
period, it should be drained, cleaned and kept dry. Where this procedure is
not possible, drain the stagnant water and rell the oil cooler with clean
sea or fresh water, which should be replaced with oxygenated sea water
every 2-3 days to avoid further decomposition.
2.5 Orifice Plates
If the sea water supply is taken from a ship’s main, it is important to ensure that
the recommended ow cannot be exceeded.
This will normally mean that an orice plate must be tted in the pipework at
least 1m before the oil cooler, with the orice size calculated to ensure that the
maximum sea water ow rate cannot be exceeded.
The correct orice diameter can be determined from the table below.
Oil Cooler
Series
Max. Sea water
ow I/min
1 bar 2 bar 3 bar 4 bar 5 bar 6 bar 7 bar 8 bar 9 bar 10 bar
EC 50 11 9.5 8.5 8 7.5 7.2 6.8 6.7 6.5 6.3
FC 80 14 12 11 10 9.5 9 8.7 8.4 8.2 8
FG 110 17 14 13 12 11 10 10 9.8 9.6 9.3
GL 200 23 19 17 16 15 14 14 13 13 13
GK 300 28 23 21 19 18 17 17 16 16 15
JK 400 32 27 24 22 21 20 20 19 18 18
PK 500 41 34 31 28 27 26 25 24 23 23
RK 900 48 40 36 34 32 30 29 28 27 26
2.6 Composite end cover water pipe installation
For marine versions supplied with composite end covers, it is recommended
that a bonded seal is used in conjunction with the tting and tightened to the
appropriate torque gure given below to ensure sucient sealing.
The following tables gives maximum ow rates for either single two or three pass
conguration, using either sea water or fresh water cooling.
Orice diameter in mm for max. sea water ow
Three Pass Bowman
Oil Coolers
Size Torque (Nm)
EC range (3/4” BSP) 10
FC range (1” BSP) 15
FG range (1 ¼” BSP) 20
GL range (1 ½” BSP) 25

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Take Care
3. Operation
3.1 Maximum water flow rates
The following tables give maximum ow rates through the tube stack for either
single, two or three pass conguration, using either sea or fresh water.
Max Recommended Flowrate (I/min) Max Recommended Flowrate (I/min) Max Recommended Flowrate (I/min)
EC range 50 80 170
FC range 80 120 230
FG range 110 170 320
GL range 200 290 560
GK range 300 450 900
JK range 400 600 1200
PK range 650 1000 2000
RK range 900 1400 2800
Max Recommended Flowrate (I/min) Max Recommended Flowrate (I/min) Max Recommended Flowrate (I/min)
EC range 75 120 255
FC range 135 200 380
FG range 180 270 530
GL range 320 470 900
GK range 460 690 1400
JK range 660 1000 2000
PK range 1000 1500 3000
RK range 1400 2150 4300
Sea Water Application (Maximum 2 m/s)
Fresh water Application (Maximum 3 m/s)
3-Pass
Type
3-Pass
Type
3.2 General information
The oil cooler should be pressurized on the oil (shell) side such that it is at a higher pressure than
the water (tube) side. This will ensure that if a leak occurs it will be detected by a reduction in the
oil level and the oil will not be contaminated. A dierential pressure of 2 bar would be sucient. It
is essential that the following instructions are followed to prevent corrosion/erosion of the heat
exchanger:
a) Always maintain the water pH to within correct levels. The ideal water pH should be kept
within 7.4 to 7.6. On no account should it be below 7.2 or above 7.8.
b) Minimum water velocity of 1m/s should be used.
c) Ensure compliance with water quality and maximum permissible pressure requirements.
d) Air must be adequately vented from both circuits.
e) Stagnant water should not be allowed to accumulate in the oil cooler. If it is not in use
for any period of time the water should be drained o.
2-Pass 1-Pass
2-Pass 1-Pass

4. Commissioning
Commissioning of the oil cooler should not be undertaken until this document has
been fully read and understood. Both circuits of the oil cooler must be
closed prior to commissioning.
Adequate provision should be made to ensure that correct operating/service
equipment along with personal protection equipment (PPE) in accordance with
current standards/legislation is used prior to the commencement of any working.
Cooling water should be introduced to the oil cooler prior to the gradual introduction
of hot oil. Both circuits should be vented initially and again when operating
temperatures and pressures are reached. The system should be checked for leaks.
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Danger
Take Care
Copper-nickel alloys have a very good resistance to seawater corrosion due to
the formation of a thin protective lm on the surface of the metal. This lm starts
to develop over the rst few days after the metal has been in contact with clean,
oxygenated seawater, and requires a further 3 months to develop fully. This is the
most important part of the process to ensure long term corrosion resistance
behaviour of copper nickel. The protective surface lm of cuprous oxide is
indicated by either a brown, greenish brown or blackish brown thin lm layer. The
process of ensuring that copper alloy receives an eective oxide coating prior to
service is known as“conditioning” which is a very important stage for the alloy.
Ferrous sulphate can be used if commissioning in clean sea water is not possible.
Schedule cleaning may help to reduce the risk possibly with non-metallic brushes.
Please refer to Copper Alliance webpage for more information: www.copper.org.
5. Maintenance / Repair
5.1 Winter shutdown in areas exposed to frost
Care should be taken to prevent frost damage from a winter shutdown in conditions exposed
to frost. We recommend draining down the oil cooler or removing the it completely from the
installation for the duration of the shutdown period.

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Take Care
5.2 General maintenance
While the unit is in operation, weekly inspection of the heat exchanger and its connections
should be made for leaks and externally visible damage. BOWMAN® recommend that the
tubestack should be cleaned and inspected annually and the o rings should be renewed at
this time. Removal of the screws around the periphery of each end cover will allow the end
covers and seals to be removed. The tubestack can then be withdrawn from either end of
the body.
5.3 Cleaning
Whilst we strongly recommend that mechanical and chemical cleaning of the heat exchanger is
carried out only by specialised companies, below are some general guidelines that may be useful;
a) Removing the end covers allows access to the tube stack, which can be removed
from the body.
b) Wash the tube plates and tubes using a hand held hose or lance. An industrial steam
cleaner can also be used if available.
c) Tube brushes can be used to clean through each tube to aid removing stubborn deposits.
Small diameter rods and brushes for tube cleaning are available from companies such as
Rico Industrial Services www.ricoservices.co.uk
d) Detergents or chemicals suitable for use with the tube material* can be used if
fouling is severe. Allow time for the detergent or chemical cleaner to work, before hosing
down with plenty of water. *Please refer to the spare parts list for details of the tube materials.
e) The tube stack should be ushed through with clean water to remove all traces
of cleaning chemicals/detergents. If necessary, the cleaning uid should be neutralised.
f) When retting the end covers after cleaning, new‘O’seals must be used
5.4 End cover screw tightening sequence
End covers must be retted in their original
orientation and tightened to the torque gures
below.
Cooler Series Screw Size Torque (Nm) Cooler Series Screw Size Torque (Nm)
EC M6 8 GK M12 54
FC M8 22 JK M16 95
FG M8 22 PK M16 130
GL M10 37 RK M16 130

6. Potential Service Issues
6.1 Tube failures
The majority of problems facing an oil cooler are those of corrosion or erosion on the water side.
Three common types of failure are:
a) Impingement attack (or erosion corrosion)
This is caused by water containing air bubbles owing at high speed through the tubes. The
impingement of rapidly moving water may lead to a breakdown of the protective copper oxide lm on
the tubes thus allowing corrosion/erosion. This is worse with water containing sand or grit. The eect of
these conditions would be pockmarking and pinholing of the tubes.
b) Oxide corrosion
This is caused by water containing organic matter such as that found in polluted estuaries. Usually
this water produces hydrogen sulphide, which is very corrosive and can cause failure of the tubes,
particularly if excessive water ows are used.
c) Pitting
This problem is caused by very aggressive sea water in the tubes, especially in partially lled coolers
where the sea water is stagnant. Low sea water ow rates can create a high temperature rise on the sea
water side. Under these conditions deposits may build or settle in the tube, allowing pitting corrosion to
take place under the deposits.
This is only a brief introduction to corrosion problems. The subject is complex and the purpose of these
notes is to outline in very general terms what may occur under extreme conditions.
6.2 Fault finding
Symptoms Possible Causes Remedy
Increase in temperature on shell
side or excessive pressure loss
Oil sludging, tube scaling or build
up of both resulting in an insulat-
ing lm covering the tubes
The complete oil cooler should
be thoroughly cleaned
Pressure loss is as expected, but
the temperature of the oil rises
Film, scale or restrictions on the
inside of the tubes
The complete oil cooler should
be thoroughly cleaned
Oil leaking into the cooling water
circuit or vice versa
Split or perforated tubes Tubes should be blocked with
hard wooden plugs as a
temporary measure & the
tubestack replaced asap
Inadequate performance Flow rates too low
Unit connected in parallel ow
Check ow rates & increase if
necessary
Reconnect in counterow as per
section 2.2
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