Almatec AHD Series Operation instructions

OPERATING AND INSTALLATION INSTRUCTIONS
High-Pressure
Diaphragm Pumps
made of Plastic
AHD Series
AHD 15
AHD 25
AHD 40
Original Instruction
Read carefully before pump installation

AHD Series · Page 2
CONTENTS
Page
1. Introduction 3
1.1. General description of the machine, appropriate use and residual dangers 3
1.2. Storage 3
1.3. Codesystem 3
2. Technical data 5
2.1. Performance charts 5
2.2. Dimensions 7
3. Installing the pump 8
3.1. Installation into the piping system 8
3.1.1. Product ports 8
3.1.2. Connecting the air supply 8
3.2. Start-up and operation of the pump 9
3.3. Further safety hints 10
3.4. Additional temperature hints 11
3.5. Providing spare parts 12
4. Disassembly of the elements of construction 12
4.1. Pump housings and manifolds 12
4.2. Suction and discharge valves 13
4.3. Diaphragms 13
4.4. Dual stage housing 14
4.5. Center block 14
4.5.1. Shaft piston rings 14
4.5.2. Air control system PERSWING P®14
4.5.3. Air filter 14
5. Assembly of the elements of construction 15
5.1. Center block 15
5.1.1. Air control system PERSWING P® 15
5.1.2. Shaft piston rings 15
5.2. Dual stage housing 15
5.3. Diaphragms 15
5.4. Suction and discharge valves 16
5.5. Housing bolts with spring washers 16
5.6. Pump housings and manifolds 16
6. Testing advises 17
6.1. Air valve 17
6.2. Correct function and sealing 17
7. Troubleshooting 18
8. Spare part list 20
9. Exploded view 21
10 Optional equipment 22
10.1. Stroke counting 22
10.2. Diaphragm monitoring 23
10.3. ANSI flange connections 23
10.4. Spare part list optional equipment 23

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1. INTRODUCTION
ALMATEC high-pressure diaphragm pumps are constructed according to the state of the art and they are
reliable. Imminent danger by operating error or misuse can lead to damages of properties and/or persons.
The pumps are to be applied for the intended use and in a safety-related proper condition only.
Each person working on the ALMATEC high-pressure diaphragm pumps concerning installation, start-up,
handling or maintenance has to read this manual completely and in an attentive way and has to follow all
mentioned procedures and safety notes.
1.1. General description of the machine, appropriate use and residual dangers
The ALMATEC AHD Series pumps are oscillating positive displacement pumps
and are based on the functional principle of double diaphragm pumps. The basic
configuration consists of two external side housings with a center block between
them. Each of the side housings contains a product chamber which is separated
from the center block by a diaphragm. The two diaphragms are interconnected
by a piston rod. Controlled by an air control system, they are alternately
subjected to compressed air so that they move back and forth. The pressure
booster centered between the diaphragms boosts the drive air pressure to more
than twice its original value in the two product chambers.In the first diagram,
the compressed air has forced the left-hand diaphragm towards the product
chamber and displaced the liquid from that chamber through the open valve at
the top to the discharge port. Liquid is simultaneously drawn in by the right-hand
diaphragm, thus refilling the second product chamber. When the end of the
stroke is reached, it reverses automatically and the cycle is repeated in the
opposite direction. In the second diagram, liquid is drawn in by the left-hand
diaphragm and displaced by the right-hand diaphragm.
The appropriate use of an Almatec high-pressure diaphragm pump of the AHD series refers to the liquid (or
sludge) transport taking into account the operation parameter mentioned in this manual and in compliance
of the given terms for commissioning, operation, assembly, disassembly and maintenance.
Even if all necessary safety measures described in this manual have been met, a residual danger exists by
leakages or mechanical damages. At sealing areas or connections liquid can be released uncontrollably then.
1.2. Storage
In general the ALMATEC pump is delivered operational and packaged. If the unit is not installed right away,
proper storage conditions are important for a trouble free operation later. The pump has to be protected
from wetness, coldness, dirtying, UV-radiation and mechanical influences. The following storage conditions
are recommended:
- Steady ventilated, dust and vibration free storage room
- Ambient temperature between 15°C (59°F) and 25°C (77°F) with a relative humidity below 65%
- Prevention of direct thermal influences (sun, heating)
1.3. Code system
The ALMATEC Maschinenbau GmbH is certified as a modern, quality-orientated enterprise according to
DIN EN ISO 9001:2008 and 14001:2004. Before release for dispatch, any pump of the AHD series has to
undergo an extended final control. The performance data registered during this are archived in our records
and can be read back at any time.
As a general rule in the countries of the EU only such machines are allowed to take into operation, which are

AHD Series · Page 4
determined to meet the regulations of the EU machinery directive, the harmonized standards, European
standards and the respective national standards. Hence the operator has to verify whether the ALMATEC
pump manufactured and delivered properly according to the customer’s order meets the mentioned
requirements.
Therefore make sure, before putting the pump into operation, that the pump and the used materials of
construction are suitable for the provided application and the installation site. To check this, the exact pump
code is required. This code, the serial number and the year of construction are noted on the identification
plates on the pump itself.
Based on the ALMATEC pneumatic diaphragm pump range, ALMATEC high pressure pumps AHD 15, AHD 25,
AHD 40 have especially been developed for the requirements of feeding filter presses. Due to the integrated
pressure transmission, they can achieve a discharge pressure of 15 bar (218 psig) with an air pressure of 7 bar
(100 psig).
Here is an example to illustrate the system of the ALMATEC pump codes:
AHD 25 E T T - C
Optional equipments:
C Stroke counting
D Diaphragm monitoring
W ANSI flange connections
Material of E EPDM
ball valves: N NBR
T PTFE
Material of diaphragms: E EPDM
N NBR
T PTFE-EPDM compound
Material of housing: E PE UHMW
Size and port dimension
ALMATEC High pressure diaphragm pump

AHD Series · Page 5
2. TECHNICAL DATA
Pump size
AHD 15
AHD 25
AHD 40
Dimensions mm (“): width
depth
height
312 (12.3)
177 (7.0)
336 (13.2)
422 (16.6)
256 (10.1)
412 (16.2)
539 (21.2)
291 (11.5)
544 (21.4))
Flange connections, port DIN or ANSI
Air connection BSP
15 (1/2”)
1/4"
25 (1”)
1/2"
40 (1-1/2”)
1/2"
Weight kg (lbs)
11 (24)
24 (53)
53 (117)
Max. particle size of solids mm (“)
4 (0.16)
5 (0.20)
8 (0.31)
Suction lift, dry mWC (‘):EPDM/NBR ball valves
PTFE ball valves
Suction lift, wet mWC (‘)
2 (6.6)
1,5 (4.9)
9.5 (31.2)
3.5 (11.5)
2 (6.6)
9.5 (31.2)
3.5 (11.5)
2 (6.6)
9.5 (31.2)
Max. driving and operating pressure bar (psig)
7 (100)
7 (100)
7 (100)
Max. operating temperature °C (°F)
70 (158)
70 (158)
70 (158)
Sound pressure level acc. to DIN 45635,
part 24, depending on the operating data
[dB (A)]: driving pressure 3 bar
driving pressure 5 bar
driving pressure 7 bar
68-77
68-84
68-85
76-86
78-88
79-88
72-84
74-85
75-87
2.1. Performance charts
The data refer to water (20°C/68°F), under using of a compressor Atlas Copco VSG30 and calibrated
measuring equipment. The specified performance data are warranted by ALMATEC in accordance with DIN
EN ISO 9906. The blue lines state the air consumption in Nm³/min.

AHD Series · Page 6

AHD Series · Page 7
2.2. Dimensions
* in mm, with DIN flanges
** in inch, with ANSI flanges
mm* A B C D E F G H I K L M N O P Q R S T U V W
AHD 15 312 152 336 316 20 37 DN15/PN16 65 M12 236 276 24 R 1/4" 263 53 150 177 520 40 112 M8
AHD 25 421 200 412 392 20 44 DN25/PN16 85 M12 336 376 36 R 1/2" 336 56 190 255 748 40 160 M8
AHD 40 539 270 544 524 20 60 DN40/PN16 110 M16 434 484 47 R 1/2" 454 70 257 291 714 50 220 M10
inch** A B C D E F G H I K L M N O P Q R S T U V W
AHD 15 12.3 6.0 13.2 12.4 0.8 1.5 ANSI 1/2" - 300lbs 2.6 1/2" UNC 9.3 10.9 0.9 BSP 1/4" 10.4 2.1 5.9 7.0 0.2 0.8 1.6 4.4 M8
AHD 25 16.6 7.9 16.2 15.4 0.8 1.7 ANSI 1" - 300lbs 3.5 5/8" UNC 13.2 14.8 1.4 BSP 1/2" 13.2 2.2 7.5 10.0 0.3 1.9 1.6 6.3 M8
AHD 40 21.2 10.6 21.4 20.6 0.8 2.4 ANSI 1-1/2" - 300lbs 4.5 3/4" UNC 17.1 19.1 1.9 BSP 1/2" 17.9 2.8 10.1 11.5 0.3 0.6 2.0 8.7 M10

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3. INSTALLING THE PUMP
The number in brackets, which is added to every part mentioned in the following explanations, refers to its
position in the spare part list and the exploded view. UV-radiation can damage the housing parts of pumps
made of PE. The operator is responsible for an adequately stability and an appropriate fixation of the piping
according to the state of the art. To facilitate the installation and maintenance shut off valves should be
installed right before and after the pump.
3.1. Installation into the piping system
Each of the shock absorbers [14] the pump is standing on is equipped with a female thread at its bottom for
easy installation of the pump. Before connecting the pump, the blind plugs have to be removed from the
suction and discharge manifolds [4] as well as the air inlet [21].
3.1.1. Product ports
In general, the pumps have to be connected load free. Neglecting this causes leakage and maybe even
damages. They cannot serve as a fixing point within a piping system. To avoid vibrations compensators on
both sides of the pump are recommended. Alternatively, hoses for suction and discharge help absorbing
vibrations. These would as well avoid the transfer of pulsation and noise onto pipes, tanks and other parts of
a plant, besides the conveyance is more gentle. These hoses have to carry an appropriate armourment to
avoid diminishing the diameter of the suction pipe by the vacuum the pump develops.
The nominal width of the connection pipes has to be chosen in accordance to the connections of the pump.
A smaller piping can cause cavitation (suction line) as well as a loss of performance (suction and discharge
line). In case the pipe is too big, the dry suction capacity of the pump can decrease. Using flanges according
to DIN DN 15/25/40 PN 16 or ANSI 300 lb/sq.inch, the suction line has to be connected to the lower manifold
[4], the discharge to the upper one. The position of the manifolds can be varied in steps of 90° for a
horizontal or vertical connection. To do so, the corresponding two housing bolts [13] have to be taken out
beforehand. After turning the manifold [4], the bolts have to be fixed and tightened again.
The first version is the standard configuration when the pump is shipped: Suction port horizontal and
discharge port vertical to the top.
Seal the suction line diligently to avoid air intrusion. A suction line continuously rising will prevent the
formation of air locks in the line which would affect the suction lift.
If pressurised air chambers are positioned beyond the pump discharge, these have to be disconnected from
the pump by non-return valves. As the ALMATEC high pressure pumps regulates itself automatically
according to the pressure of the filter press, additionally influencing the pump by a pressurised regulated air
chamber cannot be permitted on principle.
3.1.2. Connecting the air supply
The air inlet [21] is located in the middle of the center block [19]. When delivered it is covered by a bilingual
sticker with safety instructions, which can be easily removed. To supply the pump with driving air sufficiently,
an appropriate diameter of the air supply line is required, at least the same nominal size as the air inlet of the
pump (AHD 15: 1/4", AHD 25/40: 1/2"). We recommend connecting the pump via a hosepipe with adapter

AHD Series · Page 9
and sealing. If this is not available, a direct connection via pipe thread and sparingly attaching some sealing
tape is possible. Please note: The air inlet [18] is made of plastic to protect the center block [16], seal in
carefully. Take care that no dirt or particles can intrude into the pump during the connection, as these can
accumulate inside the pump and can cause malfunctions. An air filter [19] directly behind the air inlet [18]
prevents the entry of bulk particles.
The following regulators should be included in the air supply line:
Pressure regulator with maintenance unit/separator for condensed water (no oil supply)
The pressure regulator is used to adjust the final pressure the press will stop at. As a rough
orientation a doubling pressure can be assumed, e. g. with 5 bar (72 psig) air supply, the pump will
stop at a pressure of 10 bar (145 psig) inside the filter press. Please note: The time required for
pressing increases along with the pressure. A higher pressure means a more dry filter cake and
higher stress for all materials involved. A general guiding value cannot be given, the correct
pressure has to be found out for every single application.
Air throttle (e.g. needle valve)
This is helpful to limit the flow rate when starting to fill the press (without limiting the velocity,
the pump will start very fast which results in a lower quality of the filter cake and increased wear
of the pump). At the choice of the valve a sufficient pass-through capacity of the valve as well as
an easy fine tuning has to be taken care of.
Besides, the following elements can be installed in the air supply line:
Solenoid valve: depending on the automatisation; optimally installed before the pressure
regulator, as mostly regulated.
Micro filter: protects the pump from remains of dirt and oil in the compressed air. A micro filter
can replace an air maintenance unit.
Pressure relief valve: prevents irregular regulation of the pump and filter press.
The integrated air control system PERSWING P® is a precision-control that requires oil-free, dry and clean
compressed air for optimal function. The quality of the driving air for the pump depends on the operating
conditions (e.g. flow rate at the beginning, final pressure of the filter press). For a rough orientation, we
recommend to lean against the following quality classes of ISO-DIS-8573-1: solids - class 2, dew point - class
4-3, oil - class 3. Eventual icing of the muffler or the whole pump most often results from insufficiently dried
driving air. A muffler [20] soiled after short period of operation indicates soiled driving air which can be
helped by a micro filter chosen according to the max. air flow. In humid surroundings, icing from the outside
may occur despite the driving air is dried. If so, a prolonged waste-air-exhaust (ca. 500 mm / 20 inch by pipe
or hose) can be helpful. When installing the pump into boards or cabinets, it has to be ensured that cold air
does not get caught behind the muffler. ALMATEC high pressure pumps do not require any lubrication. It has
to be secured, that no oil can enter the pump. In applications with a tendency to freezing at the waste air
exhaust, good experiences in practise have been achieved by pre-heating the driving air to increase the
distance to the dew point of the air. Doing so, it has to be considered that the driving air temperature
generally may not exceed 50°C (122°F) to avoid expansion and sticking effects on the air side. This max. air
temperature is a well valid when using a compressor producing warm air which is e.g. often true for truck
compressors.
3.2. Start-up and operation of the pump
When starting to install the pump, the housing bolts [13] have to be tightened. This has to be done before
the pump develops a decent discharge pressure. The bolts [13] should be tightened crosswise and alternately
starting with those arranged in the circle of the diaphragm. The aim of this is to work against the effect of
housing parts "settling" after manufacture (e.g. during transport) because of varying temperatures.
The housing bolts [13] have to be fixed according to the torque data of the following schedule. At the
beginning, the bolts need to be checked regularly and fixed if necessary. It can also be necessary after longer
periods of stoppage, at extreme temperature variations, after transport and dismantling the pump. In case of
temperature varying between extremes or high temperature difference between the liquid and the

AHD Series · Page 10
surrounding, the housing bolts should be controlled more frequently (interval proposals are available on
request). Once the pump is leaking because of insufficient tension of the bolts, it cannot be sealed completely
by just tightening the bolts without cleaning the surfaces. The pump has to be opened and the sealing
surfaces have to be cleaned carefully. Especially the round sealing groove in the pump housing [1] needs to
be cleaned diligently.
Size
AHD 15
AHD 25
AHD 40
Torque values for housing bolts Nm (ft lbs):
8 (5.9)
13 (9.6)
24 (17.6)
The pressure of the driving air should be limited to the amount required to meet the performance needed.
Excessive pressure increases both the air consumption and the wear of the pump. The pump is regulated by
tuning the flow rate of the air. For a proper operation at the lower performance range the regulation via a
needle valve is recommended. An empty pump has to be driven slowly (e.g. via a needle-valve). The pump
starts automatically. Pumps of the AH series are self-priming when dry, thus it is not necessary to fill the
suction line of the pump. The suction lift capacity of a liquid-filled pump, however, is much higher. The pump
is appropriate for running dry during slow operation. Dry running at high stroke frequency causes premature
wear. The pumps can briefly (up to max. one hour) be operated against a closed discharge line. Throttling on
the suction side may damage the pump. When the pump operation has been stopped by a closed discharge,
the pressure equilibrium of the diaphragms must be ensured. This can be achieved by keeping the pump
connected to the air supply pressure; for longer stoppage, the pump must be released from the pressure
within the system on both fluid side and air supply side.
The ideal combinative effect of ALMATEC high pressure pumps and filter presses is illustrated very well by the
automatic adaptation to pressure and flow rate. When beginning to fill the empty press, the low discharge
pressure results in a high flow velocity for fast filling. Because of the pressure of the press increasing along
with the amount of sludge inside, the flow rate of the pump automatically reduces until standstill at final
pressure without any regulating or additional security devices. In contrast to a mechanically driven
diaphragm pump, the ALMATEC high pressure pump stops itself without any further air consumption. This
"integrated" automatic regulation permits operating the pump within its capacity without any danger of
over-pressure.
3.3. Further safety hints
Installation, operation, and maintenance by qualified staff only.
Before start-up of the pump anyone should acquaint oneself with the explanations of the chapter
troubleshooting (see pages 18/19). Only by this the defect quickly can be realized and eliminated in
case of trouble. Problems which cannot be solved or with an unknown reason should be passed on to
the manufacturer.
Before any maintenance and service procedures arising on the pump or on the optional equipment,
the complete installation has to be turned off and protected against accidental turn on. This is
possible by a lockable emergency stop for the air supply of the pump. Additional a danger sign
against restart should be attached.
Pressure tests of the plant a pump is included in may only be carried out with the pump disconnected
from the pressure on both ports or by using the pressure the pump develops while operating. The
load of a pressure in the plant may damage the pump.
AODD pumps must not be operated with a positive suction pressure.
Depending on the conditions of operation, the liquid conveyed might escape from the pump through
the muffler in case of a diaphragm rupture (in this case muffler has to be replaced). For further safety
requirements the optional equipment diaphragm monitoring and barrier chamber system are
recommended.
In case of a diaphragm rupture, it might be possible for the fluid pumped to intrude into the air side
of the pump. In very adverse conditions - e.g. pressure within the fluid system during stopped air
supply - the fluid might as well find its way into the air supply lines. To protect other devices like
pneumatic valves, it is recommended to protect the air supply line accordingly, e.g. via a non-return
valve. This would as well avoid polluting the air supply line.
The state of the muffler has to be inspected regularly, as a blocked muffler can be forced out of the
pump. If this happens, damages of properties and/or persons cannot be excluded.

AHD Series · Page 11
Pumps of the AH-Series must not be submerged.
When blowing out the filter press, the pump has to be protected against the pressure by a valve or a
slide.
If the product tends to settle, the pump has to be flushed regularly. For larger solids a filter has to be
installed in the suction line.
In case of delivery of hot liquids the wetted pump must not standstill for a longer time, because it
could lead to temporary leaks in the valve area and to a blockade of the air control system.
The relevant effective security advises have to be respected.
Pools of liquid which appear in the near outer area of the pump have to be inspected on danger
potential, if necessary safety measures are to be taken.
Chemical and biological reactions in the product chamber of the pump (mixture of different
substances) and the freezing of the liquid have to be avoided.
Before starting to disassemble the pump, take care that the pump has been emptied and rinsed.
Both ports piping are to be closed and drained if applicable. Further the pump has to be cut off from
any energy on the air and product side. If the pump is being deported from the plant, a reference
about the delivered liquid has to be attached.
Please respect the relevant additional security advices, if the pump has been used for aggressive,
dangerous or toxic liquids (e.g. suitable protective equipment according to the safety data sheet of
the liquid). In case of a diaphragm rupture, it is possible that residues of the liquid remain behind the
diaphragms, in the area of the air control system and at the muffler, despite of several flushing
processes. Hence, appropriate safety equipment according to the safety data sheet of the liquid is
indispensable.
Before putting the pump back into operation, the tightness of the pump has to be checked.
Air-operated diaphragm pumps can lead to bruises when lifting, sinking or assembling them.
Appropriate accessories and safety equipments are to be used. Big and heavy modules have to fixed
and secured to lifting gears when transporting/replacing them.
Especially when deliver critical liquids, wear parts, like diaphragms, should be replaced within a
preventive maintenance.
The use of non-original ALMATEC spare parts and structural changes lead to the lapse of the
warranty immediately. When operating such a pump, damages of properties and/or persons cannot
be excluded.
The operation of the pump with nitrogen as driving gas is possible. In closed rooms sufficient
ventilation must be provided.
Possible electrical connections (e.g. when using optional equipment with controllers) may be
executed by a qualified person only. The regulations of the respective manufacturers are to be
followed.
At any work arising it has to be made sure that no explosive atmosphere can appear. Appropriate
safety equipment is recommended.
The pump is tested with water before shipment. Water residues inside the pump cannot be
precluded. If the liquid, which is wanted to be conveyed, potentially interacts with water, please
consult Almatec.
Procedure for pump return: According to the requirements of our 14001-certification, every unit
which is send to ALMATEC for diagnosis or maintenance reasons has to be accompanied by a filled
out decontamination-sheet. Otherwise a processing is not possible. The decontamination-sheet is
enclosed to this manual. Please pay attention to the further safety regulations.
3.4. Additional temperature hints
The temperature and pressure limitations listed on page 5 are solely based on mechanical temperature limits
of the housing material used. Depending on the fluid pumped, the maximum safe operating temperature of
the housing material can be reduced significantly.
A general aspect of lower temperatures is, that below 0°C (32°F) cold-brittling of the elastomers used within
the pumps can results in accelerated wear. Regarding the housing materials, please note that PE - other than
PP - keeps its mechanical strengths at low temperatures. ALMATEC pumps can therefore be operated safely
as well within low-temperature installations: However, with liquids below 0°C (32°F) accelerated wear of
internal parts has to be accepted. Moreover, freezing, bogging or crystallisation of the fluid pumped must be
avoided, especially within the pump.

AHD Series · Page 12
Please consider, that viscosity and specific gravity of most fluids change with temperature (most often
increasing at lower temperature). Depending on the application, this fact may not only result in result in a
reduced flow rate, the pump may even be unable to prime the thicker and/or “heavier“ fluid any more.
In case of varying application temperatures, the housing bolt tension has to be controlled very thoroughly, as
variations like these can change the effective tension of the housing bolts via the different thermal expansion
characteristics of single.
3.5. Providing spare parts
We recommend having spare part kits S on stock. These include the relevant spare parts for your pump.
4. DISASSEMBLY OF THE ELEMENTS OF CONSTRUCTIONS
When dismantling a pump the mentioned procedures and safety notes on the pages 8-12 have to be
considered generally.
ALMATEC high-pressure diaphragm pumps are often used to transport sludge, so that deposits and
incrustations inside the pump can complicate the disassembly. It has been proved to be useful to soak the
components before dismantling in water (if compatible with rinsing agent) to facilitate the separation after a
certain waiting period.
The general design of the ALMATEC high pressure pumps is simple. Every pump comes along with a mounting
tool for the air-valve system [22]. Take out the muffler [30] installed onto the center block [16] before
dismantling the pump to protect it against damages during the disassembly.
Required tools
AHD 15
AHD 25
AHD 40
Item
Description
Tool
Tool size
Tool size
Tool size
8
Lock pin, discharge valve
Screwdriver
Please check yourself
10
Plug
Open-end spanner
30 mm
36 mm
50 mm
13
Housing bolt
Open-end
spanner/ring
wrench/socket
wrench
10 mm
13 mm
17 mm
21
Air inlet
Open-end spanner
19 mm
27 mm
27 mm
22
PERSWING P® air control system
ALMATEC Tool
+ ring wrench
1 15 901 54
24 mm
4.1. Pump housings and manifolds
At first, loosen those bolts [13] at the top and at the bottom using a wrench and take them out together with
the tension plates [3]. After that, unscrew the remaining housing bolts [13], remove the tension discs [2] and
draw the housing bolts [13] out to the left until they are left of the right hand side diaphragm [17]. Now, the
right pump housing [1] can be taken away (if necessary carefully help it move with a rubber hammer). Draw
out both manifolds [4] and remove the O-rings [11,12].

AHD Series · Page 13
4.2. Suction and discharge valves
Image 1 Image 2
Lay down the pump housing [1] on its outer surface. Loosen lock pin discharge valve [8] and remove. Turn the
discharge valve [7] along its longitudinal axis by 180° using a suitable round bar (Image 1). After ca. 70°
change the bar to the other side of the discharge valve [7] (Image 2) and keep on turning the remaining 110°.
Take care not to damage the sealing surface for the diaphragm (V-groove) during this. Draw the discharge
valve [7] downwards and take it out (Image 3). Withdraw O-Ring, valve [40]. The discharge valve ball [18] can
be taken out easily now. The valve stop [9] can be shoved downwards to take it out (Image 4).
Image 3 Image 4
Unscrew the plug [10] out of the pump housing [1]. Use a suitable round bar (possible also is the shaft
bushing long [39]) to press out the suction valve [5] from outside to inwards through the bore of the plug
[10]. Take this as well as the suction valve ball [18] and the valve seat [6] out. Draw of O-ring, valves [40].
4.3. Diaphragms
After following the instructions above you will now have a unit consisting of the left pump housing [1] the
center block [19] and the dual stage housing [15] with the housing bolts [13] partly torn out to the left.
To disassemble the diaphragms [17] reach behind the right diaphragm [17] and screw it off the shaft [32].
Take out the diaphragm disc [41] afterwards. Insert two long suitable screws (e.g. two housing bolts) into the
threaded bores of the supporting disc [31] for approximately 10 mm (0.4 inch). Position a round bar as a
handle in between them and loosen the supporting disc (do not yet screw off completely) (Image 5). Take the
remaining housing bolts [13] out of the left pump housing [1] and remove the housing (disassembly of the
suction and discharge valves as described above [4.2]). Turn off the left diaphragm [17] as well.

AHD Series · Page 14
Image 5 Image 6
Now, a supporting disc [31] is visible on each side which can be disassembled as follows: Screw two suitable
screws (e.g. two housing bolts) as well approx. 10 mm deep into the threaded bores of the on the left side
hand supporting disc [31]. Attach a round bar in between those to unscrew the supporting disc [31] on the
right and to fix the other disc (Image 6). Shove the shaft [32] into the right side and unscrew the other
supporting disc [31] as well. Take out the shaft [32] and separate the center block [19] and the dual stage
housing [15]. Take care not to damage the O-Ring dual stage bushing [36] when disassembling the shaft [32],
lead the thread through this O-Ring by screwing.
4.4. Dual stage housing
The dual stage housing [15] is the smaller of both blocks in the middle of the pump. Loosen the dual stage
bushing [16] along with the dual stage piston [35] from the dual stage housing [15] and push the dual stage
piston [35] out of the dual stage bushing [16]. Take out the shaft bushing, short [33]. The sealing elements
[33,36,37,38] have to be replaced in case they are soiled or damaged. As far as the piston rings are
concerned, we refer to their own chapter 4.5.1. within this manual.
4.5. Center block
Take the shaft bushing, long [39] out first and lay the center block [19] plainly onto a soft base (do not
damage the sealing edges!).
4.5.1. Shaft piston rings
Remove both parts of the shaft piston rings [20] from their grooves carefully (do not damage the edges in the
center housing) A re-assembly of the same piston rings is impossible; they have to be replaced. Handle the
piston rings in the dual stage housing [15] the same way.
4.5.2. Air control system PERSWING P®
Screw off both end caps of the PERSWING P® air control system [22] using the plastic mounting tool delivered
with the pump. Take out main and pilot piston. Press out the air-valve housing with the mounting tool turned
around.
4.5.3. Air filter
To take out the air filter [29] the air inlet [21] has to be screwed off first, afterwards the filter [29] can be
unscrewed easily with a big screw driver.

AHD Series · Page 15
5. ASSEMBLY OF THE ELEMENTS OF CONSTRUCTION
5.1. Center block
5.1.1. Air control system PERSWING P®
To install the air control system PERSWING P® [22], first screw in one end cap flushly into the center block
[19]. Insert one of the six O-rings, air-valve housing [24] into the end cap from the inside. Moisten the four O-
rings [24] of the air-valve housing with a bit of water and push the housing into the center block [19] using
the mounting tool. Take care that it slips in softly. Do never insert the housing violently with a hammer. In
case the housing cocks or hardly gets in, take it out again completely and start again. Insert the main piston
and the pilot piston. Lay the sixth O-Ring [24] on the edge of the air-valve housing and screw in the second
end cap.
5.1.2. Shaft piston rings
The O-Rings located underneath the piston rings [20] have to be installed first. A
re-assembly of the used piston rings is impossible; they have to be replaced! To
assemble piston rings [20], carefully shape them like kidneys with locking ring
pliers and insert the rings into the grooves; completely press the rings into the
grooves smoothly using a clean housing bolt [13]. Insert the shaft bushing, long
[39] on side of the center block were the big O-ring dual stage bushing [38] is
located.
5.2. Dual stage housing
Install piston rings [rings and O-rings,20] as described. Insert the shaft bushing, short [33] on the side of the
big O-ring dual stage bushing [38]. Insert the O-rings, dual stage bushing into their grooves in the dual stage
housing [15] respectively the center block [19]. Lay the dual stage bushing [16] into the dual stage housing
[15] and afterwards insert the dual stage piston [35] with the conic side at first (corresponding to the shape
of the dual stage housing [15]) into the dual stage bushing [16].
5.3. Diaphragms
At first, the center block [19] and the dual stage housing [15] have to be put together and the shaft [32] has
to be shoved in rotatingly with care. The threads on both sides of the shaft differ in their lengths. Screw the
first supporting disc [31] onto the shaft [32] up to its block at the side where the thread is the shorter. Attach
the other supporting disc [31] tightly on the other end and tighten the fist disc as well (for tightening the
discs, follow the disassembly instructions 4.3). Take the screws used for fixing (e.g. two housing bolts) out of
the supporting discs [31]. Align the bore holes in center block [19] and dual stage housing [15]. Put on the
diaphragm discs [41] on both sides.
Screw a diaphragm [17] on one side onto the shaft [32] until it blocks. Take care that the bore holes for the
housing bolts are aligned between the diaphragm [17], the center block [19] and the dual stage housing [15].
Insert three housing bolts [13] carefully as an assembly auxiliary. Push the diaphragm [17] into the center
block [19] resp. dual stage housing [15] as far as possible. Screw the second diaphragm [17] up to its block
onto the other end of the shaft (watch out for all bores to be aligned, if necessary, slightly turn back the
diaphragm). Shove in the remaining housing bolts [13] finally.
The sealing surfaces of the diaphragms [17] and the pump housings [1] have to be absolutely clean and
undamaged; mere small scratches can cause leaking.

AHD Series · Page 16
5.4. Suction and discharge valves
The inner parts of the pump housings [1] have to be re-assembled exactly vice versa to the way described for
the disassembly. Ensure that the suction [5] and discharge valves [7] are pushed into their extreme position
and that the bores in the pump housings [1] (at the bottom of the liquid camber) and the suction valves [5] fit
to each other. Make sure that the hole in the pump housing [1] and the thread of the locking pin discharge
valve [8] are aligned, then install locking pin discharge valve [8] in the discharge valve [7] and screw it.
5.5. Housing bolts with spring washers
When assembly the housing bolts [13] pay attention to the correct
arrangement of the spring washers. The pump sizes AHD 15 / AHD
25 have three spring washers on both housing bolt sides and the
AHD 40 have four pieces. The arrangement represented in the
drawings makes an improvement of power and way possible.
Already used spring washers may not be installed again.
5.6. Pump housings and manifolds
All the sealing elements [11,12] of the manifolds [4] should always be replaced, moisturising the rings helps
to ease the assembly. Draw the inner O-ring [12] onto the manifold [4] and press the outer O-ring [11] into
the pump housing [1]. Set the manifolds [4] on the plainly lying pump housing [1] slightly rotating them. Put
the central unit mounted before [center block, dual stage housing, diaphragms, housing bolts] and the pump
housing [1] lying on its side with the manifolds [4] standing upwards together, namely in the way that the air
inlet [21] ends up right of the dual stage housing [15].
Mount the second pump housing [1]. Now, both the upper and lower pair of housing bolts [13] can be
inserted. Make sure that the position of the manifolds [4] matches the installation situation, to avoid later
readjustment. Install tension discs [2] and tension plates [3]. Attach nuts and washers to the ends of the bolts
and fix the housing bolts [13] crosswise evenly according to the given torque values until the pump housings
[1] are situated on the center block [19] respectively the dual stage housing [15]. Any further tightening of
the bolts does not improve sealing but can deform the housing!
Finally screw the muffler [30] into the center block [19]. The pump can be operated now.

AHD Series · Page 17
6. TESTING ADVISES
6.1. Air control system
The correct function of the air distribution can easily be checked for an assembled center unit consisting of a
center block [19] completely and dual stage housing [15] equipped with all inner parts. Attach the air supply.
Move the pilot piston back and forth while the bores where the air leaves the center block [19] are blocked.
Now, the switching and the movement of the main piston have to be audible.
6.2. Correct function and sealing
The fully assembled ALMATEC high pressure pump has to be equipped with an air supply as well as
temporary suction and discharge lines both leading to a water containment. The dry suction capacity can be
checked with a vacuum gauge by closing the suction line carefully complete. Slowly closing the discharge has
to cause standstill of the pump. The pressure in the discharge line has to correspond to the air pressure
(Attention: the maximum permissible air pressure is 7 bar / 100 psig; which evokes a max. operating pressure
of 15 bar / 218 psig!). The pump switches to the other product chamber by scarcely opening the discharge for
a short time. No liquid may escape from the pump in both positions. After finishing the test, the air supply
has to be closed at first, after that the discharge line has to be opened slowly to let the pump empty itself
while the suction line is opened.

AHD Series · Page 18
7. TROUBLESHOOTING
Malfunction
Possible Reason
Solutions/Remarks
pump does not operate
air supply line blocked/closed
muffler blocked
working chambers blocked
air control system defective
discharge line blocked/closed
open air supply
clean/replace muffler
remove blockage
replace air valve system
clean/open line
pump operates unsteadily
piston rings worn
air control system worn
diaphragm rupture
air control system soiled
check valve blocked
icing
replace piston rings
replace air control system
replace diaphragm, clean pump
clean/replace air control system
cleaning, removal of bulk particles
improve air processing
air within liquid
suction line leaky
container with liquid empty
diaphragm rupture
cavitation
seal suction line
fill/new container
replace diaphragm
adapt suction lift, possibly install
suction pressurised air chamber
insufficient discharge pressure
insufficient pressure/amount of
driving air
air supply line leaky
air control system leaky
check valve worn
more air consuming components
increase air supply
check/repair air supply
replace air control system
check/replace check valve
increase pressure/amount of air
output decreases
air control system soiled
icing
air pressure drop
suction line/inlet strainer soiled
discharge line/outlet strainer soiled
muffler blocked
check valve worn
change in viscosity
more air consuming components
clean/replace air control system
improve air processing: dryer/filter
ensure sufficient supply of air
cleaning
cleaning
replace the muffler
replace valve
change back/adjust pump
increase pressure/amount of air
pump stops itself
icing of the air control system
air pressure to low
air pressure drop
discharge line blocked
air filter blocked
valve closed
air control system defective
wear/leaking of air control system
diaphragm rupture
check valve blocked/worn
improve air processing:
dryer/heater etc.
increase air pressure
ensure sufficient air supply
clean discharge line
clean air filter
open valve
replace air control system
replace air control system
replace diaphragm, clean pump
clean/replace check valve

AHD Series · Page 19
Malfunction
Possible Reason
Solutions/Remarks
pumps operates, however suction
capacity insufficient
pump operates too fast
operation beyond physical limits
cavitation
operation beyond pump capacity
air cushion within suction/discharge
line
dry suction against discharge
pressure
valve filter within suction line closed
valve filter within discharge line
closed
container with liquid empty
vacuum inside the container
wear of the check valves
suction line leaky
suction line blocked
air pressure cushion at discharge
check valve blocked
start more slowly
adjust installation
check, cool down
adjust installation resp. install
bigger pump
bleed the line
wet pump, start without pressure
open valve/clean filter
open valve/clean filter
fill/new container
bleed container
replace valves
seal suction line
clean suction line
bleed discharge line
clean/replace valve
insufficient suction capacity after
pump repair
connections tighten incompletely
check valves inserted falsely
tighten/seal connections
correct positioning of check valves
diaphragm overstrained
pressure within the plant/system
inadmissible vacuum
icing
ensure that pressure is only
developed by the pump itself,
check plant/valves,
replace diaphragms
check suction line, open valve
improve air processing
leaking between housing parts
housing bolts loosened
O-rings sleeve damaged
diaphragms attacked chemically
diaphragms overstrained
tension installation/pipework
tighten bolts, check pump
replace O-rings
replace diaphragms
replace diaphragms
loosen, eliminate tension,
use of a compensator
muffler grey
driving air too humid, icing
improve quality of driving air
muffler black
soiled, oily air
improve quality of driving air,
install sensitive filter in suction line
pump is connected to air but does
not operate
air control system blocked
bulk particles/dirt
chemical influence (O-rings
swollen)
valve closed in discharge line
clean/replace air control system
clean pump, replace necessary
parts, improve air quality
check, replace damaged parts
open valve
liquid leaves the pump via the
muffler
diaphragm rupture
replace diaphragms,
clean pump

AHD Series · Page 20
8. SPARE PART LIST
Pump size
AHD 15
AHD 25
AHD 40
Item
Pc.
Description
Material
Part number
Part number
Part number
1
2
Pump housing
PE
3 15 510 52
3 25 510 52
3 40 510 52
2
2
Tension disc
1.4301
3 15 508 22
3 25 508 22
3 40 508 22
3
4
Tension plate
1.4301
3 15 608 22
3 25 608 22
3 40 608 22
4
2
Suction/discharge port
PE
3 15 511 52
3 25 511 52
3 40 511 52
5
2
Suction valve
PE
3 15 013 52
3 25 013 52
3 40 013 52
6
2
Suction valve seat
PE
3 15 014 52
3 25 014 52
3 40 014 52
7
2
Discharge valve
PE
3 15 515 52
3 25 515 52
3 40 515 52
8
2
Lock pin, discharge valve
PETP
3 15 519 84
3 15 519 84
3 40 519 84
9
2
Ball retainer
PE
3 15 016 52
3 25 016 52
3 40 016 52
10
2
Plug
PE
1 25 017 52
3 25 017 52
1 40 017 52
11
4
O-Ring, ports, outside
EPDM
9 37 528 72
9 42 540 72
9 65 516 72
12
4
O-Ring, ports, inside (code EEE/ENN)
EPDM
9 33 526 72
9 33 526 72
9 51 513 72
O-Ring, ports, inside (code ETT)
FEP/FKM
9 33 553 59
9 33 553 59
9 50 554 59
13
12
Housing bolt
1.4301
3 15 520 22
3 25 520 22
3 40 520 22
14
4
Shock absorbers
NR
1 15 322 85
1 15 322 85
1 40 322 85
15
1
Dual stage housing
PA
3 15 148 53
3 25 148 53
3 40 148 53
16
1
Dual stage bushing
PETP
3 15 049 84
3 25 049 84
3 40 049 84
17
2
Heavy duty diaphragm (code EEE)
EPDM
3 15 031 72
3 25 031 72
3 40 031 72
Heavy duty diaphragm (code ENN)
NBR
3 15 031 71
3 25 031 71
3 40 031 71
Heavy duty diaphragm (code ETT)
PTFE
3 15 031 67
3 25 031 67
3 40 031 67
18
4
Valve ball (code EEE)
EPDM
1 25 032 72
3 25 032 72
3 40 032 72
Valve ball (code ENN)
NBR
1 25 032 71
3 25 032 71
3 40 032 71
Valve ball (code ETT)
PTFE
1 25 032 60
3 25 032 60
3 40 032 60
19
1
Center block
PA
3 15 140 53
3 25 140 53
3 40 140 53
20
3
Shaft piston ring, cpl.
PTFE
1 40 041 64
1 50 041 64
3 40 041 64
21
1
Air inlet
PETP
1 15 047 84
1 40 047 84
1 40 047 84
22
1
PERSWING P® air control system, cpl.
PETP
2 15 001 84
2 40 001 84
2 50 001 84
24*
6
O-ring, air valve housing
NBR
9 35 504 71
9 46 515 71
9 66 533 71
29
1
Air filter
PE
1 15 043 51
1 40 043 51
1 40 043 51
30
1
Muffler
PE
1 15 244 51
1 40 244 51
1 50 244 51
31
2
Supporting disc
AL
3 15 533 31
3 25 533 31
3 40 533 31
32
1
Shaft
1.4301
3 15 030 22
3 25 030 22
3 40 030 22
33
1
Shaft bushing, short
1.4301
3 15 035 22
3 25 035 22
3 40 035 22
34
2
O-ring, shaft bushing
NBR
9 24 514 71
9 30 510 71
9 36 591 71
35
1
Dual stage piston
AL
3 15 034 31
3 25 034 31
3 40 034 31
36
1
O-ring, dual stage piston
FKM/NBR
9 10 507 74
9 12 506 71
9 17 557 74
37
1
Piston ring, cpl.
PE
3 15 037 52
3 25 037 52
3 40 037 52
38
2
O-ring, dual stage bushing
NBR
9 99 567 71
9 99 562 71
9 99 573 71
39
1
Shaft bushing, long
1.4301
3 15 036 22
3 25 036 22
3 40 036 22
40
4
O-ring, valves (code EEE/ENN)
EPDM
9 37 603 72
9 48 604 72
9 72 605 72
O-ring, valves (code ETT)
PTFE
9 37 603 60
9 48 604 60
9 72 605 60
41
2
Diaphragm disc
PTFE
3 15 039 60
3 25 039 60
3 40 039 60
* included in item 22
All parts in italics are not product wetted.
Please see page 4 for explanation of the pump code.
When ordering please state the serial number of the pump.
For spare part lists for special equipment please see page 22 and the following ones.