Helium Technology S.r.l. has been established in 2010 to answer properly to the growing requests of
leak testing using helium as tracing gas in strategic industrial sectors as refrigeration, pharmaceutical,
food, automotive, etc., where the quality requirements are getting more and more strict.
The company belongs to Marposs group.
Helium Technology employs highly specialized personnel, with long time experience in this
sector. It can consequently support the customer during all the different phases of the process,
from the definition of the technical specifications and the most suitable solution at quotation
stage, to the design, development and manufacturing of dedicated application, up to the after
sales service. To perform this activity the company takes advantage of Marposs distribution
network, present in 23 countries with own sales offices and after sales service centres.
Marposs, established in 1952 by Mario Possati, is the leader supplier of precision
instruments for dimensional and geometrical measurement of mechanical parts in the
shop floor environment: gauges and control systems for machine tools, manual and
automatic systems for manufacturing and assembly lines, hardware and software for
data collection and process analysis, non destructive testing equipment and leak test
systems, with particular reference to components of car engine, transmission and injection.
The Headquarters and the main plant are located in Bentivoglio (BO).
Helium Technology - Calvignasco (MI)
Marposs - Bentivoglio (BO)
Leak testing is a non destructive method to verify the presence of a leak in a component or
device. The presence of a leakage could jeopardize the correct functioning of the component or
device or its life span, and also be potentially dangerous for the environment and for the safety
of its user.
There are different methods to verify the presence of a leakage, from the traditional immersion of
the component in a water tank, to the air detection in pressurized parts up to the use of tracing gas.
The use of helium as tracing gas for leak detection is a consolidated system in the main industrial
sectors, mostly where there is a high technological content, but it is quickly expanding to other
sectors due to the increasing requirements of the market for high quality.
Leak flow in mbar*L/s
mbar.l/s
10-10
10-9
10-8
“small” leaks
“small”
leaks
10-7
10-6
10-5
10-4
10-3
10-2
“industrial” leaks
“industrial”
leaks
10-1
10+0
10+1
10+2
10+3
“big”leaks
leaks
“big”
Bubble decay
test
Pressure
Pressure
Bubble decay
test
Helium leak
leak detection
Helium
detection
WHY HELIUM?
Helium is the second lightest element after hydrogen: it can penetrate small leaks rapidly (where
heavier elements could not) up to 10−11 mbar*L/s.
Is a noble gas: it is inert and does not react with other gases or with the part under test.
Is ecological: it is colorless, odorless, tasteless, non-toxic and does not create any problem in
case of dispersion in the environment.
Is present in the atmosphere only in small quantities (5 ppm) and so the background noise for
the leak detection instrument is very low.
HOW DOES IT WORK
The usage of helium as tracing gas to find and quantify leaks requires
an instrument able to detect its presence.
The instrument is the mass spectrometer, that transforms the
measurement of the mass of a gas into an electric signal.
To do this, the air that enters the spectrometer is ionized
and guided into a curved tube immersed in a magnetic field.
For a given value of the magnetic field only helium ions go through,
while the others are destroyed. The electric current produced by the
helium ions flow is measured to quantify the leak.
HEAVY
IONS
source
LIGHT
IONS
HELIUM
IONS
detector
TEST METHODS
Helium charged - vacuum test
The part is put into a chamber where vacuum is created. The part is then pressurized
with helium and the helium leakage is measured through a mass spectrometer.
The test is objective, since does not depend on the operator.
Detectable leak range goes from 5.0 x 10-3 mbar*L/s to 5.0 x 10-8 mbar*L/s.
This method is used in automatic systems to test components as evaporators,
condensers, tubes, hoses, pipes, airbags, canisters, fuel tanks, thermostatic valves.
Helium charged - sniffer test
The part is pressurized with helium. The mass spectrometer is fitted with a sniffer
probe that is moved over the areas of possible leak to detect its presence. The test
can be performed manually (by operator) or automatically.
The detectable leak range is between 5.0 x 10-3 mbar*L/s and 5.0 x 10-5 mbar*L/s.
This test is used for parts that cannot be put inside a vacuum chamber (refrigerators,
refrigerated food displays) or to locate a leak that has been detected by other
methods, in order to allow for parts repair.
Helium spray - vacuum test
The part to be tested is directly connected to a mass spectrometer and put inside
a chamber. Vacuum is created inside the part and the helium concentration in the
chamber is raised to 100%. If a leakage is present, the molecules of helium migrate
into the part and the leakage is measured by the spectrometer.
The possible leak range to be detected is from 5.0 x 10-3 mbar*L/s to 5.0 x 10-8
mbar*L/s.
This test is frequently used to check porosities in cast parts or for parts that operate
under vacuum, as water pumps and brake pumps.
Bombing test
This method applies to parts that are supposed to be sealed, as implantable medical
devices and bulbs.
The component under test will be first exposed for an extended length of time (e.g.
10 minutes) to a high helium pressure (40-50 bar) in a “bombing” chamber.
If the part is leaky, helium will be able to penetrate the device.
Then the component will be placed in a vacuum chamber. The amount of helium
that entered the device will be released in the vacuum chamber and measured by
the mass spectrometer.
This method is not able to detect small leaks. Usual leak range to be detected is
from 5.0 x 10-2 mbar*L/s to 1.0 x 10-4 mbar*L/s.
APPLICATION FIELDS
--------------
Refrigeration
Air conditioning
Automotive
Aerospace
Fire extinguisher
Pressurised containers
Valves
Carbonated beverage containers
Food packaging
Pharmaceutical
Petrochemical
Energy
Microelectronics
SEMI-AUTOMATIC LEAK TEST MACHINE
FOR A/C HOSES
Test type
Helium charged – vacuum test
Productivity
250 parts/h
Reject limit
2.0 x 10-5 mbar*L/s
corresponding to 3 g/y
Test pressure
(max)
40 bar
SEMI-AUTOMATIC LEAK TEST MACHINE
FOR LPG TANKS
Test type
Helium charged – vacuum test
Productivity
30 parts/h
Reject limit
2.0 x 10-4 mbar*L/s
corresponding to 18 g/y
Test pressure
(max)
4 bar
SEMI-AUTOMATIC LEAK TEST MACHINE
FOR COOLING SYSTEM VALVES
Test type
Helium charged – vacuum test
Productivity
160 parts/h
Reject limit
7.0 x 10-6 mbar*L/s
corresponding to 1 g/y
Test pressure
(max)
60 bar
SEMI-AUTOMATIC LEAK TEST MACHINE
FOR CONDENSERS
Test type
Helium charged – vacuum test
Productivity
140 parts/h
Reject limit
2.0 x 10-5 mbar*L/s
corresponding to 3 g/y
Test pressure
(max)
40 bar
AUTOMATIC ASSEMBLY LINE AND
LEAK TEST MACHINE FOR FUEL TANKS
Test type
Helium charged – vacuum test
Productivity
65 parts/h
Reject limit
2.0E -4 mbar*L/s
Test pressure
(max)
300 mbar abs
SEMI-AUTOMATIC LEAK TEST MACHINE
FOR BLOOD FILTERS
Test type
Helium charged – vacuum test
Productivity
1350 parts/h
Reject limit
3.0E -4 mbar*L/s
Test pressure
(max)
300 mbar abs
SEMI-AUTOMATIC LEAK TEST MACHINE
FOR FOOD PACKAGE
Test type
Helium charged – vacuum test
Productivity
1100 parts/h
Reject limit
1.0 x 10-4 mbar*L/s
Test pressure
(max)
300 mbar abs
SEMI-AUTOMATIC LEAK TEST MACHINE
FOR GASOLINE “FUEL RAIL”
Test type
Helium charged – vacuum test
Productivity
60 parts/h
Reject limit
1.0 x 10-4 mbar*L/s
corresponding to 6 g/y
Test pressure
(max)
200 bar
HELIUM RECOVER SYSTEM
Efficiency
between 85% and 95%
Flow range R1 model from 100/150 nL/min
Flow range R2 model from 200/300 nL/min
Flow range R3 model from 300/450 nL/min
Helium pressure
“out”
max 80 bar (adjustable)
Helium pressure “in” max 1.3 bar absolute
Helium refilling
pressure
max 6 bar
Marposs in the world:
www.marposs.com/addresses
Visit the
www.hetech.marposs.com website
Edition 04/2016 - Specifications are subject to modifications. © Copyright 2012-2016 MARPOSS S.p.A. (Italy) - All rights reserved.