IVAR MULTIPRESS User manual

300484EN|2021-11|rev00
MULTI•PRESS®
USER MANUAL
MULTIPRESS® - USER MANUAL

MULTI•PRESS®
User manual

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© 2021 IVAR S.p.A
INDEX
INTRODUCTION 4
FITTING SPECIFICATIONS 4
COMPATIBILITY 4
MATERIALS AND COMPONENTS 5
RANGE 6
SPECIAL FIGURES 8
U-Fittings
Under-floor distribution box fitting
ASSEMBLY AND INSTALLATION ACCESSORIES 9
INSTALLATION INSTRUCTIONS* 9
Cutting the pipe
Calibration
Chamfering
Inserting the pipe onto the press fitting
PIPE BRACKET* 11
Fixing points and surface mounting
Use of expansion legs in risers
Linear expansion in pipes
Example
Positioning
QUALITY CONTROL AND PRODUCTION PROCESS 15
Receipt of materials
Analysis during machining
* Credits: FRÄNKISCHE, Germany

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© 2021 IVAR S.p.A
ASSEMBLY 15
MULTI•PRESS® fitting assembly
LABORATORY TESTS 17
Reference standards
Traction
Thermal cycles
Vibration
Water hammer
CALCULATION OF PRESSURE DROPS 18
Distributed pressure drops
Concentrated pressure drops
Equivalent length
PRESSURE TESTING TO EN 806 PART 4 19
Test procedure
Procedure A
Procedure B
Procedure C
CERTIFICATION 20
SPECIFICATION ITEMS 21
FITTING DIMENSIONS 25

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© 2021 IVAR S.p.A
■ INTRODUCTION
MULTI•PRESS® is a system of multi-crimping profile press fittings available in a com-
plete range of figures for multilayer pipes from 16x2 to 63x4.5 mm diameter. The
MULTI•PRESS® range of multi-crimping profile press fittings offers versatility and flexi-
bility during installation. The fittings are designed, tested and guaranteed for use with
seven crimping profiles: BE, B, TH, R, H, F and U. They can be used with multilayer pipes
in climate control and sanitary DHW/DCW systems.
Figure 1. Tee fitting.
■ FITTING SPECIFICATIONS
• Tested and guaranteed for use with seven crimping profiles: BE, B, TH, R, H, F, U;
• Control of correct pipe positioning via the inspection holes in the bushing flange (orange plastic up to 32 mm diameter;
white plastic from 40 to 63 mm diameter)
• Two o-rings for a more secure seal
• Wide range of diameters from 16 mm to 63 mm
• Maximum continuous operating temperature 120 °C (check the pipe specifications for the effective limit of the system)
• Maximum operating pressure 10 (bar check the pipe specifications for the effective limit of the system)
• High pull-out resistance thanks to the sawtooth insert profile
• Optimised bush/fitting coupling system to prevent detachment of the steel bush.
■ COMPATIBILITY
Diameter (mm) 16 18 20 25 26 32 40 50 63
BE ✓ ✓ ✓ ✓
B
✓✓✓ ✓✓
F
✓✓✓ ✓✓✓✓✓
R
✓✓✓✓✓✓
H
✓✓✓✓✓✓✓
TH ✓✓✓✓✓✓✓✓✓
U
✓✓✓ ✓✓✓✓✓

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© 2021 IVAR S.p.A
■ MATERIALS AND COMPONENTS
The materials used in the fittings are:
• Body: brass, CW617N or Cuphin® CW724R (Pb ≤ 0.1%)
• Bushes: AISI 304 solution heat treated stainless steel
• Bush holders: nylon
• O-ring: peroxide-cured EPDM, certified safe for food contact and use in potable water systems
Body
The MULTI·PRESS range is available in two versions, with fitting body in CW617N brass or Cuphin®
CW724R (alloy with ≤ 0.1% lead content).
Both brass alloys are contained in the 4MS “Positive List” and can therefore be used in domestic potable
water distribution networks.
The sawtooth profile of the fitting terminals helps grip the pipe inside the fitting itself, increasing the pull-
out resistance in the event that the pipe-fitting system is subjected to tensile stress.
Bush
The bushes used in MULTI·PRESS fittings are made of AISI 304 solution heat treated stainless steel.
This material, in addition to guaranteeing long-term performance, also offers increased ductility, which
facilitates the crimping operation and ensures greater longevity of the crimping tools. The bush always
carries the name of the manufacturer, the diameter and thickness of the multilayer pipe with which the
fitting can be used, as well as the traceability symbol which identifies the month and year of production
of the fitting.
Bush holder
Made of plastic, this prevents direct contact between the brass body of the fitting and the aluminium
layer of the pipe, thus acting as a dielectric coupling; this prevents any damage due to electrolytic
corrosion due to contact between dissimilar metals. The bush holder also features inspection holes
which allow the installer to check correct positioning of the pipe once inserted.
O-ring
Each fitting has two peroxide-cured EPDM o-rings on each connection which, after crimping, ensure a
perfect seal between the pipe and fitting. The o-rings meet all applicable European standards, allowing
Multi·Press to be used in sanitary DHW/DCW systems.

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© 2021 IVAR S.p.A
■ RANGE
MULTI·PRESS press fittings are available in a broad range of configurations and sizes from 16x2 to 63x4.5. All figures
with corresponding dimensional tables are provided in the appendix.
MP 5700 R
Straight reduced fitting
MP 5717
Elbow fitting with flat-seal lock nut
MP 5700
Straight fitting
MP 5760
Wall fitting
MP 5704
45° fitting
MP 5761
Wall fittings (kit with AS 1929)
MP 5710
Elbow fitting
MP 5762
Wall fittings (kit with AS 1927)
MP 5720
Tee fitting
MP 5780
Double wall fitting
MP 5720 RLL
Tee fitting with reduced side connections
MP 5765
Double wall fittings (kit with AS 1929)
MP 5720 RCL
Tee fitting with reduced central and side
branches
MP 5766
Double wall fittings (kit with AS 1927)
MP 5720 RC
Tee fitting with reduced central connec-
tion
MP 5781
Double 90° wall fitting
MP 5720 RL
Tee fitting with reduced side connection
MP 5769
Double 90° wall fittings (kit with AS 1929)
MP 5720 RR
Tee fitting with double reduced connec-
tions
MP 5723
Wall fitting for horizontal chases

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© 2021 IVAR S.p.A
MP 5608
Male straight fitting
MP 5724
RH wall terminal for horizontal chases
MP 5711
Male elbow fitting
MP 5725
LH wall terminal for horizontal chases
MP 5721
Male tee fitting
MP 5764
Wall terminals for horizontal chases (kit
with AS 1928)
MP 5609
Soft-seal male straight fitting
MP 5701
Plug
MP 5607
Straight fitting with FASTEC fitting
MP 5702
Straight fitting with chrome-plated copper
pipe
MP 5613
Female straight fitting
MP 5715
Elbow fitting with chrome-plated copper
pipe
MP 5712
Female elbow fitting
MP 5716
Tee fitting with chrome-plated copper
pipe
MP 5712 L
Long female elbow fitting
MP 5729
Built-in valve with DN 15 press-fit fitting,
knob and rose
MP 5722
Female tee fitting
MP 5730
Built-in valve with DN 15 press-fit fitting,
cap and rose
MP 5703
Straight fitting with flat-seal lock nut
MP 5610 B
Under-floor distribution box with 90°
press fitting
MP 5705
Straight fitting with lock nut
MP 5610 R
Under-floor distribution box with 90°
press fitting

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© 2021 IVAR S.p.A
■ SPECIAL FIGURES
U-Fittings
As well as properly distributing water to all connected components, any sanitary DHW/DCW plumbing system must guar-
antee the best hygienic conditions possible by preserving the quality of the mains water supply.
A sanitary DHW/DCW distribution system is composed of different sections of piping:
 Main distribution ring
 Ascending or descending risers
 Horizontal distribution sections to the floors
 Connections to the terminal units (i.e. basins, baths, showers etc.)
There are several possible options for these. The two best known are shown in the following images, with branch connec-
tion (left) or via manifold (right), which are not ideal from a sanitary perspective.
Figure 2 Branch system. Figure 3 Manifold system.
Indeed, those pipe segments serving rarely used components suffer from a lack of water circulation, meaning the water
in these becomes stagnant. The same water sitting inside pipes over a long period of time encourages the proliferation of
bacteria (including legionella), and should therefore be avoided as much as possible.
IVAR’s MP range of fittings includes the 5780 series, which is essential for installations such as those shown in the follow-
ing figures and which implement a series- (left) and a ring- (right) type distribution system.
Figure 4 Series distribution system. Figure 5 Ring distribution system.
In both cases, the goal of these configurations is to facilitate water circulation in the pipes, thus avoiding stagnation and
reducing health risks. In the case of series distribution (left), the component used most frequently should be in the furthest
position from the column so that every time this is used, the water is replaced completely through circulation in all the
branches. In the case of ring distribution (right), the use of any plumbing fixture achieves the same result, making this dis-
tribution system the most effective for reducing hygienic risk. Depending on given regulations, there may be a requirement
to build facilities for hospitals and community structures using a ring distribution system, including an automatic withdrawal
point activated by timer. This ensures periodic water circulation in the system up to the terminal units during the thermal
disinfection cycles.
Under-floor distribution box fitting
Multilayer pipes are installed in corrugated conduit in some systems, for example,
when additional protection is required or in countries where installation regulations
require the pipes to be removable. For connection to the terminal units in these cases,
the MP5610 series under-floor distribution box fittings are required. Made with a 1/2"
F connection, these accommodate the corrugated protective conduit inside, keeping
the pipe insulated up to the point of exit from the masonry wall. The CW617N brass
fitting is fixed to the plastic box by a pair of screws, so that it can be easily disassembled
for crimping and then reinserted in the box.
Figure 6 Hidden distribution.

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■ ASSEMBLY AND INSTALLATION ACCESSORIES
AR 01
Calibration device for multilayer pipes
AR 02
Calibration set for multilayer pipes
including carry case
AR 09
Grip for multilayer pipe calibration device
AR 04
Calibration devices for multilayer pipes
AR 37
Battery crimping machine with carry case,
battery and charger
AR 10 R
Jaws for press fittings
AR 37 B
Battery
AR 37 C
Battery charger
AR 110
Pressing collars
AR 120
Intermediate jaw for pressing collars
■ INSTALLATION INSTRUCTIONS
Cutting the Pipe
Figure 7 Pipe Cutting Procedure.
Cuts in multilayer pipe must be performed to specifications using suitable pipe shears which prevent ovalisation of the
pipe, ensuring that the cut is perpendicular to the pipe profile.
Credits: FRÄNKISCHE, Germany

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© 2021 IVAR S.p.A
Calibration
Figure 8 Calibration Procedure.
The calibration operation determines the correct internal diameter of the pipe while the chamfering operation bevels the
end of the pipe so as to avoid the displacement of the o-rings from their seat during insertion. Correct calibration and
chamfering requires use of the AR 01 tool.
 For 16x2, 18x2, 20x2, 26x3 and 32x3 pipes, use code 500406
 For 40x3.5 pipes, use code 500407
 For 50x4 pipes, use code 500408
 For 63x4.5 pipes, use code 500409.
Alternatively, it is possible to use the complete set of calibration tools item no. AR 02 (code 501797).
Chamfering
Figure 9 Chamfering Procedure.
1. Insert the tool inside the pipe, making sure it enters the cutting blades.
2. Rotate the tool to create a bevel inside the pipe.
3. Lubricate the o-rings on the fittings with water and insert the pipe onto the fitting.
WARNING! Use only water to lubricate the fittings. Use of mineral-based oil or grease is prohibited.
It is also prohibited to change the original o-rings.
Credits: FRÄNKISCHE, Germany
Credits: FRÄNKISCHE, Germany

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© 2021 IVAR S.p.A
Inserting the pipe onto the press fitting
Figure 10 Inserting the Pipe.
Figure 11 Crimping Procedure.
1. Insert the fitting up to the stop.
2. Ensure that you have reached the correct installation depth thanks to the opening on the plastic ring. If excessive
resistance is encountered during insertion of the fitting, repeat the calibration/chamfering operations and lubri-
cate the o-rings again with water.
3. Open the jaws of the crimp tool and insert the fitting to be crimped, ensuring that the plastic ring is inserted in the
reference groove (with B and TH profile jaws), or that the jaws are in contact with the plastic ring (with F, H and U
profile jaws).
4. Operate the crimping tool following the instructions given in the user manual.
Crimping is performed with the AR 37 electric crimping tool. Consult the manufacturer's instructions to ensure correct use
of these tools.
■ PIPE BRACKET
Fixing points and surface mounting
For surface mount installations, it is recommended that straight lengths of pipe be
used for convenience (ALPEX-DUO and IVAR-APEX B).
The maximum unsupported distance ”S”, for surface-mount pipework in walls or
ceilings installation, is given in the following table.
Figure 12 Surface-mount installation on walls.
Credits: FRÄNKISCHE, GermanyCredits: FRÄNKISCHE, Germany
Credits: FRÄNKISCHE, Germany

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© 2021 IVAR S.p.A
Pipe size (mm) Weight of pipe with water (kg/m) S (cm)
Horizontal Vertical
16x2 0.225 120 150
18x2 0.267 130 150
20x2 0.355 135 150
25x2.5 0.608 150 175
26x3 0.608 150 175
32x3 0.935 165 200
40x3.5 1.438 200 200
50x4 2.264 250 250
63x4.5 3.611 250 250
For ALPEX-DUO and IVAR-APEX B installed in the floor, the fastening points must be at minimum intervals of one metre.
Appropriate fastening collars must also be used immediately before and after all elbows.
Use of expansion legs in risers
It is essential to use expansion legs (indicated in the following figures with ” a”) also for pipes passing through a hole which
connect to risers between floors. The expansion leg will be able to absorb movements due to changes in length. It is es-
sential to make use of a section of corrugated conduit or insulation to protect the pipe in the area where it passes through
the hole. Do not place pipe bends near sharp edges, as there is a risk of damage in this case.
Figure 13 Example of expansion leg. Figure 14 Example of expansion leg. Figure 15 Example of expansion leg.
Linear expansion in pipes
The pipe brackets have a dual purpose, both to support the pipework and to handle changes in length caused by tempera-
ture variations occurring during operation. The brackets can be rigid or of sliding type, that is able to allow axial movement
of the pipe. The pipework must always be laid out so that changes in length are not restricted. In general, fixed brackets
can be installed at the centre of long lengths of pipe, in order to allow any change in length to occur in two directions.
Figure 16 Fixed pipe bracket. Figure 17 Sliding pipe bracket.
Figure 18 Use of pipe brackets.
Credits: FRÄNKISCHE, Germany Credits: FRÄNKISCHE, Germany Credits: FRÄNKISCHE, Germany
Credits: FRÄNKISCHE, Germany
Credits: FRÄNKISCHE, Germany
Credits: FRÄNKISCHE, Germany

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Example
Assuming a temperature variation of 50° C and a pipe length of 5 metres (with IVAR ALPEX DUO pipe), the following in-
crease in length will occur:
ΔL = 0.026 mm/m°C • 50 °C • 5m = 6.5 mm
The linear expansion values for pipe are given below in millimetres, depending on ΔT and pipe length.
Pipe length Temperature differential ΔT (°C)
m 10 20 30 40 50 60 70
1.0 0.3 0.5 0.8 1.0 1.3 1.6 1.8
2.0 0.5 1.0 1.6 2.1 2.6 3.1 3.6
3.0 0.8 1.6 2.3 3.1 3.9 4.7 5.5
4.0 1.0 2.1 3.1 4.1 5.2 6.2 7.3
5.0 1.3 2.6 3.9 5.2 6.5 7.8 9.1
6.0 1.6 3.1 4.7 6.2 7.8 9.4 10.9
7.0 1.8 3.6 5.5 7.2 9.1 10.9 12.7
8.0 2.1 4.2 6.2 8.8 10.4 12.5 14.6
9.0 2.3 4.7 7.0 9.4 11.7 14.0 16.4
10.0 2.6 5.2 7.8 10.4 13.0 15.6 18.2
Positioning
The positioning of expansion legs is essential in the case of changes in length or direction. The example on the left is a
situation where it is essential to use an expansion leg on a change of direction.
The example on the right shows a situation where it is useful to apply a U-shaped bend: on very long pipes without changes
in direction, it is recommended to use a U-shaped bend with two expansion legs installed vertically to absorb the linear
expansion, and a fixed collar on the horizontal section.
Figure 19 Fixed pipe bracket. Figure 20 Change of direction.
Another example where an expansion leg is required on the change of direction is shown below.
a: expansion leg
da: pipe outer diameter
FP: fixed pipe bracket
GP: sliding pipe bracket
L: pipe length
ΔL: linear expansion
Ls: expansion leg length
Figure 21 Change of direction.
Credits: FRÄNKISCHE, Germany Credits: FRÄNKISCHE, Germany
Credits: FRÄNKISCHE, Germany

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ΔL (m) = α • L • ΔT
Ls= C • √(da• ΔL)
where:
α: coefficient of expansion (1/°C)
C: constant depending on the type of material (33 for
ALPEX DUO and IVAR-APEX B pipe)
da: pipe outer diameter (mm)
L: pipe length (m)
ΔL: linear expansion (mm)
Ls: expansion leg length (mm)
ΔT: temperature differential (°C)
Figure 22 Sizing graph examples.
Formulas for calculating the length of an expansion leg and graphs allowing for immediate sizing are given below.
Credits: FRÄNKISCHE, Germany

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© 2021 IVAR S.p.A
■ QUALITY CONTROL AND PRODUCTION PROCESS
The production process for IVAR press fittings is monitored throughout. The characteristics of the end product depend on
the care taken in its production. Some of the most important aspects of this are described below.
Receipt of materials
The body of the fitting blank comes from VALMON STAMPATI s.p.a., a Brescia-based
industrial company part of the I.V.A.R. group, which deals with the printing of semi-fin-
ished products starting from brass bars, obtaining the shape of the final piece, which
will then be deburred and sandblasted.
IVAR's Quality Control department receives the samples of the raw brass components
forming the body of the MULTI•PRESS® fittings and checks their dimensions using a 3D
scanning process. An operative uses a mobile scanner to do this.
The physical component is compared with the technical drawing, and if it falls within
the tolerances, the lot is accepted for processing. Otherwise, the nonconformity is re-
ported to the stamping company.
Figure 23 Three-dimensional scanning.
Analysis during machining
The machining process for entire production batches is begun only after analysis of the
initial samples of the machining itself. If they conform with the technical department’s
drawings, production of the batch begins.
Throughout the entire machining process, the QC operatives take samples of the
com-ponents from the machines. Samples are checked with an optical dimensional
verification tool through a comparison with the mathematical 3D reference model. For
press fittings, for example, the critical dimensions are the threads, the bases where
the bush holders will rest, and the seats for the seal-ing o-rings. In the event of non-
conformities, batch production is halted and all items produced up to that point are
checked again with the optical scanner.
The bodies of the MULTI•PRESS® press fittings are now ready to move on to the as-
sem-bly phase with the other components.
Figure 24 Comparison with technical drawing.
■ ASSEMBLY
IVAR has dedicated machinery for preparing just the bush including the polymer bush holder. During this process, the bush
is also laser engraved with information on the size of the fitting, the certifications and the crimping profiles which can be
used. The purpose of this preliminary process is to speed up the supply of components to the machines which handle assembly
of the press fitting.
MULTI•PRESS® fitting assembly
The assembly station for the fittings is supplied with the necessary components via automated systems. The fitting bodies
enter the machine via a loading choke system which ensures constant supply of one piece a time. Each piece is analysed
by a vision system with video camera which recognises the profile and associates it with the correct assembly program,
defining its pick-up co-ordinates for the robotic arm.
On board the machine, the fitting body is placed on the rotating table and reaches in turn the workstations required to
obtain the end result.
For example, in order to make up a single-bush fitting with a single outlet for multilayer pipe, the fitting passes through
two stations.
The first is responsible for inserting the two peroxide-cured EPDM sealing o-rings on the connection. Correct insertion of
the o-rings is monitored by a dedicated video camera which films and analyses all the MULTI•PRESS® fittings manufactured
by IVAR.

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Figure 25 Assembly station schematic diagram.
A. Rejected components
B. 20 mm bushes
C. 16 mm bushes
D. 20 mm O-rings
E. Assembly machine
F. Division system and robot
G. Machine onboard PC
H. Case tipper
I. Body parts feeding
L. Packaging machine
The second station fits the bush including bush holder on the fitting body. From here, the fitting reaches the end of the
rotating table and is placed inside the package, which contains the correct quantity of fittings destined for sale.
A scale checks the weight of the bagged fittings to ensure that there have not been any errors during the process, and the
bag is placed inside the recycled cardboard box.
Throughout the assembly process, the QC operatives monitor the components by picking samples. Moreover, each ma-
chine is network-connected and monitored remotely. It is possible to monitor the cycle times and performance over time,
as well as any anomalies.
Figure 26 Process control. Figure 27 Assembly station rotating table.

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■ LABORATORY TESTS
Reference standards
IVAR bases most of its laboratory tests on the DVGW W-534 worksheet, a unambiguous basis for the assessment of
fittings, joints and pipes for use in contact with potable water.
Traction
The purpose of this test is to define the mechanical characteristics of
the pipe-fitting system. During the test, it must not be possible to pull
the pipe out of the fitting, the pipe must not crack, kink or bend, while
the fittings must not sustain damage which could affect their operation.
The pipes are clamped in a device for stress testing, which allows the
maximum axial traction force to be reached without bending and/or
kinking. The maximum traction force is reached in 10-15 seconds and
held for more than an hour, with deviations of 2.5% permitted. The test
is carried out at 20 ± 5 °C and 93 ± 2 °C; different test pieces are used
for the two different temperatures.
Figure 28 Schematic diagram of the test
Thermal cycles
The thermal cycles test is a fatigue test which guarantees the reliability
of the IVAR pipe-fitting system over time. In the first part of the test, a
circuit is assembled composed of pipes and fittings in accordance with
schemes set out by the reference standard. Once ready, the circuit un-
dergoes 5,000 thermal cycles of alternating hot and cold water. The du-
ration and temperature of the individual cycles depend on the specific
case. Generally, IVAR bases its tests on the specifications provided by
the DWGV W-534 worksheet. For an even more complete assessment
of the pipe-fitting system, IVAR may adopt further tests in addition to
those mentioned.
All components of the circuit must hold their seal throughout and at
the end of the test. This also applies for threaded fittings of the fittings
being examined, where applicable.
Figure 29 Schematic diagram of the test
Vibration
This test is designed to check the compatibility of the pipe-fitting sys-
tem and ensure the pipe does not detach from the fitting. Two sections
of pipe connected by a fitting undergo the combined action of two
factors:
 Internal water pressure greater than 15 bar
 Mechanical misalignment stress of ±10 mm at a frequency of 20 Hz.
The test is passed if no breakages or leaks occur after the number
of vibration cycles provided for by the reference standard.
Figure 30 Schematic diagram of the test
Water hammer
This test is designed to check the mechanical robustness of the fitting
and the absence of leaks. The test is performed with pipes and with at
least three fittings for each of the dimensions under examination.
The test is performed at an ambient temperature of 20 ±5 °C with
water as the pressure transmission fluid. Within the test circuit, the
pressure is quickly and repeatedly varied from the minimum value (0.5
bar) to the maximum value (25 bar) at which it is to be tested.
Figure 31 Schematic diagram of the test

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© 2021 IVAR S.p.A
■ CALCULATION OF PRESSURE DROPS
As it passes through the pipework and the terminal devices making up the system, the fluid is subject to a reduction in
pressure known as pressure drops.
Distributed pressure drops
For every metre of pipework which the fluid flows through, a distributed pressure drop (or head loss) is assigned. The
following equation can be used to calculate this:
Where:
 w: velocity of the fluid [m/s]
 μ: kinematic viscosity of the fluid [Pa s]
 R: radius of the pipe in question [m]
 L: length of the pipe in question [m]
The pressure drop is therefore directly proportional to the viscosity and the velocity of the fluid, and the length of the pipe;
it is inversely proportional to the square of the radius of the pipe.
Concentrated pressure drops
There are losses due to obstacles such as bends, elbows, valves and fittings that the fluid may meet as it flows through the
pipes. These factors are defined as concentrated pressure drops and do not depend on the length of the pipework. They
can be expressed using the following formula:
Where:
 ρ: density of the fluid [kg/m3]
 w: velocity of the fluid [m/s]
 β: coefficient of friction This is a dimensionless quantity whose value, generated experimentally, depends in turn on
the Reynolds number, the internal roughness of the piping and the distance covered by the fluid from the pipe inlet.
Equivalent length
In order to size the circulation pump for the climate control system (or to check compatibility with the available pressure
in the sanitary DHW/DCW system), it is necessary to find the sum of pressure losses along the entire plumbing circuit. This
can be done in two ways: analytically, by adding together the distributed and concentrated losses of each component, or
else by using a simplified method.
This consists of calculating the pressure drops of the components of the system as if they were generated by a linear
section of pipe LEQ of a certain length.
The total pressure drops of the system are calculated with the following formula:
Where:
 ρ: density of the fluid [kg/m3]
 w: velocity of the fluid [m/s]
 D Diameter of the pipe in question [m]
 βcoefficient of friction
Finally, LEQ is the sum of the equivalent lengths for all roughness encountered by the fluid in its passage through the sys-
tem. In order to convert the concentrated pressure drops into equivalent lengths of pipe, it is advisable to use conversion
tables supplied by the manufacturers of the components in question.