Fukuda FL-601 Series Quick start guide

10491-T-001E-1
MULTIPUROSE AIR LEAK TESTER
OPERATIONAL MANUAL
FL-601SERIES
FUKUDA CO., LTD.
http://www.fukuda-jp.com
Thank you for purchasing the All Purpose Air Leak
Tester Model FL-601.
For best operating results and optimum efficiency, read
this instruction manual thoroughly to understand the
tester’s many functions prior to operation. Please keep
this manual within reach.

1
Introduction
Introduction Thank you for purchasing the Fukuda FL-601 series masterless air leak tester.
This manual is designed to provide FL-601 users with details on basic functions,
operating procedures, and safety guidelines. For best operating results and
optimum efficiency, read this instruction manual thoroughly to understand the
tester’s many functions prior to operation. Please keep this manual within
reach.
・
The contents of this manual may be modified without notice due to function
and performance improvements.
The tester’s actual external appearance may differ from the pictures
indicated in this manual.
This manual is written and explained based on example specifications for
the FL-601. However, the operating principles may be the same for other
specifications as well.
・
This manual has been written with care to provide the user with helpful and
useful information. Please contact your local FUKUDA distributor if there
are any inaccuracies or questions of concern.
FUKUDA distributor addresses are listed at the back of this manual.
・Reprinting or duplicating this manual partially or completely is prohibited
unless permitted by FUKUDA CO., LTD.
・Please do not read out, analyze, or publish this equipment’s installed
system software.
・Exporting this equipment requires permission from the Japanese
government in accordance to standards of the International Currency
Regulation and International Trade Control Law.
・For best operating results and optimum efficiency, read this instruction
manual thoroughly to understand the tester’s many functions prior to
operation.
Declaration
・The text in this manual is written according to FL-601 software version 1.**
Don’t use this tester for any purpose other than testing air leaks.
・Company names and product names being used in this manual are the
registered trademarks of their respective holders.
Trademark
・This air leak tester’s testing method is currently patent pending.

2
FOR YOUR SAFETY
Please read the “Safety Precautions” section thoroughly prior to operating this
equipment.
In this operation manual, pictographs and markings are used to indicate situations that may cause
injury to operators or other personnel, or cause potential damage to property. Descriptions of
each pictograph and symbol are indicated below. Please read this manual in its entirety prior to
handling the equipment and be sure to keep it handy at all times during operation.
PICTOGRAPHS THAT ARE USED IN THIS OPERATION MANUAL
PICTOGRAPHS DESCRIPTIONS
DANGER
Ignoring this warning and mishandling equipment may
result in serious injury or possible death.
WARNING
Ignoring this warning and mishandling equipment may
result in injury or possible death.
CAUTION
Ignoring this marking and mishandling equipment may
result in possible injury or property damage.
CAUTION : May cause electrical shock
TERMS THAT ARE USED IN THIS OPERATIONAL MANUAL
TERMS DESCRIPTION
Turn off the main
switch
(1) This implies not only turning off the power switch, but also turning
off all power supply sources to the equipment from other fixtures.
This is to prevent current from other machines from reaching the
air leak tester through its power terminal or other connections.
(2) When the equipment is being used independently, it implies that
the power plug should be disconnected from the power.
Turn off the Air
Pressure Source
This implies not only terminating the air pressure supply into the
equipment but also suspending the air pressure supply source and
making sure that there is no pressure remaining in the equipment.

3
FOR YOUR SAFETY
Descriptions for the icons used in this manual are shown below.
SYMBOLS DESCRIPTIONS
These points are essential for testing correctly and are reminders to
prevent problems from occurring. It may also highlight instructions
that are necessary to avoid malfunction and incorrect evaluations.
For your reference
Labels that are affixed to the Leak Tester Body
WARNING
MEMO
LABEL
(1) Do not remove the tester unit’s cover.
(2) Some parts inside of the tester carry a high
voltage and may be driven unexpectedly, due to the
tester’s mechanical sequences. Possible electrical
shock or injuries may result. (Only qualified
personnel should perform maintenance and service
procedures.)
DANGER

4
FOR YOUR SAFETY
●DURING OPERATION
■ ONLYUSEWITHTHESPECIFIEDVOLTAGEANDPRESSURE
・Do not apply electrical voltage other than what is designated for this equipment. Neglecting
this warning may result in fire, electric shock, or equipment malfunction.
・ Do not apply pressure other than what is designated for this equipment. It may cause an
explosion or damage the equipment.
■ DO NOT REMOVE THE COVER
・There are high temperature, high voltage, and high pressure areas within the equipment.
Removing the cover may result in electric shock, burns or other injuries. Contact our service
personnel regarding periodic or routine maintenance. Only qualified personnel should perform
maintenance and service procedures. If maintenance is to be performed, turn off the main
power and the compressed air source, and ensure that the air leak tester is in a stable
environment.
■ CYLINDER CONTROL
・When controlling clamp cylinder actuation via signals from the air leak tester, provide an
area sensor to help alleviate injuries. Cylinders may move unexpectedly due to gravity and
the weight of the jigs when the main power and pneumatic supply are terminated. We
recommend employing lock-up cylinders to avoid such problems.
■ DONOTPLACEFOREIGNMATERIALSINTOTHETESTER
・Do not insert foreign materials such as metals or inflammable materials into the tester through
the vent hole or other openings. It will damage the tester and could possibly cause fire or
electrical shocks.
■ SYSTEMDESIGN
・The system is designed with a protection/security circuit to ensure that the system remains
secured in emergency situations such as tester malfunction or breakdown.
■ POWER SUPPLY FRAMEGROUND
・Provide class 3 grounding for the power supply FG terminal. Potential electric shock may occur
if grounding is not properly secured.
■ DONOTSTEPONTHETESTER
・Do not play on the tester or use it as a step or footstool. The tester may fall down or break, and
cause possible injuries.
・Do not place anything on the tester. Items may fall and cause injuries.
■ DO NOT DISCONNECT THE COMPRESSED AIR SUPPLY UNLESS NECESSARY
・Do not disconnect the compressed air supply connected to the fixture, air filter, and pressure
regulator while they carry compressed air. An inadvertent disconnection will cause a large
amount of compressed air to spurt out, and may cause possible injuries and eye impairment
that could lead to blindness.
WARNING
CAUTION

5
FOR YOUR SAFETY
■ DO NOT OPERATE UNDER INCOMPLETE SYSTEM CONDITIONS
・Do not operate the tester unless under ideal working conditions. Factors such as lack of
workspace, incomplete piping or unsuitable conditions may cause the tester to spurt out a large
amount of compressed air, and could cause injuries and/or eye impairment that could lead to
blindness.
・Do not open/close the ball valves on the rear panel while they are under pressure. It may cause
compressed air or residual pressure to spurt out unexpectedly when unclamping. It may also
cause possible injury or eye impairment that could lead to blindness.
■ LONGTERMSHUTDOWN
・Be sure to turn off the main power source and to cut off the air source for safety.
●MISCELLANEOUS
■ WHEN DAMAGED POWER CORDS, WIRING AND/OR PIPING ARE FOUND
・When damaged power cords, wiring and/or piping are found, cut off the main power and
compressed air source immediately, and replace the damaged parts. Continued use of
damaged parts will cause fire, electric shock, and may rupture piping.
■ INTRUSIONOFFOREIGNMATERIALS
・If water, oil, or other foreign materials enter the tester, immediately cut off the main power
and the compressed air source. Continued operation of damaged testers can cause fire, or
possible electric shock. Contact your local FUKUDA distributor for technical advice.
■ DROPPED OR DAMAGED TESTERS
・When a tester is dropped, inadvertently falls, or breaks, cut off the main power and compressed
air source immediately. Continued operation of damaged testers can cause fire or possible
electric shock. For repair, contact your local FUKUDA distributor.
■ CONTINUEDUSEOFDAMAGEDTESTERSWILL…
・Continued use of damaged testers will cause irregular conditions such as smoke discharge, other
odd smells, or unusual sounds, and may lead to fire or electrical shock. Immediately cut off the
main power and compressed air sources, and make sure that it is no longer smoking. (Make
sure that it does not start a fire. If necessary, notify people nearby about this potential danger).
For maintenance and repair, contact your local FUKUDA distributor.
WARNING

6
FOR YOUR SAFETY
■ ENFORCING PERIODIC CHECKUPS FOR YOUR FUKUDA TESTER
・This tester requires periodic checkups, maintenance and overhaul to maintain reliable test
results and precision. Regular cleaning to remove accumulated dust and lint inside of the
tester will eliminate the possibility of fire or electrical leaks. Accumulated dust, lint and oil in
the power plug outlet, tester connector, and terminal board may also result in fire or electrical
leaks. Enforce periodic checkups and keep the tester as clean as possible.
■ SECURE A PROPER OPERATING ENVIRONMENT
・Use and keep this tester in an environment which has been specifically designated according to
our specifications. This tester cannot be used where flammable, explosive, or vaporizing gas is
present.
・Be certain that the power supply meets specifications prior to your initial power connection.
・Using a welder close to this tester may damage it and is not recommended. Do not press the
touch panel or control keys on this tester with sharp objects.
・Do not wipe the tester with paint thinner or other solvents for cleaning purposes.
CAUTION

7
CONTENTS
INTRODUCTIO
N
1 P
FOR YOUR
SAFETY
2 P
CONTENTS 7 P
OUTLINE TESTER CHARACTERISTICS 10 P
TESTER MODEL 11 P
TESTER SPECIFICATIONS 12 P
EXCLUSIVE OPTION (APU) MODEL, & SPEC 13 P
(EXHAUST BYPASS & CHARGE BYPASS UNITS ) MODEL, & SPEC 14 P
ADDITIONAL EQUIPMENT 15 P
PRINCIPLE WHAT ISAN AIR LEAK TESTER? 18 P
THE IMPORTANCE OF LEAK TESTING AND THE PERMISSIVE LEAK
RATE
18 P
LEAK TESTER DETECTION LIMITS 18 P
LEAK TESTING PRINCIPLES 19 P
THE RELATION SHIP BETWEEN INDICATION AND LEAK RATE 20P
WHAT IS MASTER-LESS LEAK TESTER? 21P
CONVENTIONAL METHOD 21 P
MASTERING TESTING 21 P
POWER ON
PROCEDURE
DO YOU HAVE EVERYTHING? 24 P
TESTER STRUCTURE 24 P
ACCESSORY ITEMS 24 P
TEST PRESSURE REGULATOR 25 P
FILTER REGULATOR 25 P
PNEUMATIC REGULATOR 25 P
ADDITIONAL EQUIPMENT 26 P
THE NAMES OF EACH PART 28 P
MAIN BODY 28 P
CONNECTOR PARTS 30 P
CONTROL KEYS 31 P
INSTALLATION INSTRUCTIONS 32 P
OPERATION ENVIRONMENT 32 P
ABOUT THE WORK/MASTER 33 P
ABOUT THE MASTER TANK HANDLING 33 P
TRANSPORTATION INSTRUCTIONS 33 P
INSTALLATION SIZES 34 P
INSTALLATION MEASUREMENTS 34 P
MOUNTING TOOLASSEMBLY 34 P
BASIC PIPING 35 P
SELECTING REMOTE EQUIPMENT 36 P
CONNECTION TO EXTERNAL EQUIPMENT 37 P
REMOTE TERMINAL CHART 37 P
SEQUENCER CONNECTION EXAMPLE 39 P, 40 P
SWITCH CONNECTION EXAMPLE 39 P, 40 P
EXH. VALVE SIGNAL TERMINAL CHART 41 P
EXTERNAL SV CONNECTION
APU CONNECTION TERMINAL CHART 41 P
TIME CHART 42 P
OPERATION STAGES 43 P
REMOTE JUDGMENT CHART 44 P
POWER CONNECTION 46 P
POWER CORD CONNECTION 46 p
CONNECTING THE POWER CORD 46 P
OFF POWER SWITCH 47 P
ABOUT FUSE REPLACEMENT 47 P

8
CONTENTS
BASIC OPERATION BASIC OPERATION 50 P
SETTING CONTENTS 51 P
SETTING PROCEDURES 53 P
TESTING OPERATION ORDINARY TESTING FUNCTION 58 P
MASTERING TESTING FUNCTION 61P
PRINTER OPERATION 64P
RS-232C OUTPUT 68 P
MAINTENANCE FUNCTIONS WHAT ARE MAINTENANCE FUNCTIONS? 72 P
VOLUME MEASUREMENT USING AFLOW MASTER 73 P
VOLUME MEASUREMENT USING AMANUAL CALIBRATOR 76 P
I/O CHECK FUNCTIONS 81P
SELF-CHECK FUNCTIONS 84 P
STABILITY CONFIRMATION FUNCTIONS 87P
SOFTWARE VERSION DISPLAY 89P
APU TUNING 91 P
CAL PORT OPEN 94 P
OPTIONAL EQUIPMENT EXHAUST BYPASS UNIT 96 P
CHARGE BYPASS UNIT 99 P
APU UNIT (PNEUMATIC REGULATOR) 102P
DAILY MAINTENANCE ERROR MANAGEMENT 108 P
MAINTENANCE & INSPECTION 110 P
DAILY INSPECTIONS 110 P
PERIODIC INSPECTIONS 110 P
SUPPLEMENT MASTERLESS Q&A 112 P
PNEUMATIC CIRCUIT DIAGRAM 117P
EXTERNAL DIMENSIONS 120 P
WARRANTY REPAIR REGULATIONS
WARRANTY
FUKUDADISTRIBUTORS LIST

9
OUTLINE

10
OUTLINE TESTER CHARACTERISTICS/ TRAITS
■ TESTER CHARACTERISTICS
The FL-601 is an air leak tester which has improved performance by using fitting technology to
provide the most efficient air leak testing performance.
This equipment has the following characteristics:
(1) A restricted function set allows highly efficient leak testing at reasonable costs.
(2) Compact size allows installation of more than one unit without consuming too much space.
(3) Operational data/information is displayed on an LCD, enabling easy operation.
Furthermore, the FL-601 features the following functions:
•No Master Required
(Ano-leakstandard)
By eliminating the master used in differential pressure air
leak testing methods, costs are reduced and testing space
is minimized.
•Improved detection accuracy
By stabilizing the internal air alteration in the fitting
side chamber, detection sensitivity
is greatly improved.
Improved data compensation technology enables highly
sensitive detection without interference from negative
environmental factors.
•Can set up to 16 different conditions Capable of setting up to 16 different processing conditions.
•Self –check function
The self-check function notifies you of any malfunctions
that occur in any valve or miscommunications made by the
sensors. It is also possible to detect sensor malfunctions
triggered by deterioration.
•Data control function
It is possible to transmit data to external devices via
RS-232C. Transferred data can then be analyzed using
software such as LOTUS or EXCEL.

11
OUTLINE TESTER MODEL
■ TESTER MODEL
ＦＬ－６０１➊－➋－➌
➊ PRESSURE RANGE
Model Applied Pressure Setting Pressure Range Indicated Pressure Range
Ｖ -5.0 ～ -90.0 kPa 0.0 ～ -90.0 kPa 0.0 ～ -90.0 kPa
ＵＬ 5.0 ～ 20.0 kPa 0.0 ～ 20.0 kPa 0.0 ～ 50.0 kPa
Ｌ 10.0～ 99.9 kPa 00.0 ～ 99.9 kPa 00.0 ～ 99.9 kPa
Ｍ 100 ～ 700 kPa 0 ～ 700 kPa 0 ～ 999 kPa
Ｈ 300 ～ 990 kPa 0 ～ 990 kPa 0 ～ 999 kPa
Ｈ１ 0.50～ 2.00 MPa 0.00 ～ 2.00 MPa 0 ～ 2.00 MPa
Please consult your nearest representative for pressures lower than the UL range.
➋ POWER SUPPLY VOLTAGE
Model POWER SUPPLY VOLTAGE
２ AC90 ～ 110V 200 ～ 240V
➌ EXTERNAL OPTION
Model Product Name Note
FR-51 Filter/ Regulator Unit Positive Pressure UL Range Standard spec. R5
FR-52 Filter/ Regulator Unit Positive Pressure UL Range Precision spec. P-200
FR-53 Filter/ Regulator Unit Positive Pressure L Range Standard spec.
FR-54 Filter/ Regulator Unit Positive Pressure L Range Precision spec.
FR-55 Filter/ Regulator Unit Positive Pressure L Range Precision spec. and
High Performance spec. Filter
FR-56 Filter/ Regulator Unit Positive Pressure M Range Standard spec.
FR-57 Filter/ Regulator Unit Positive Pressure M Range Precision spec.
FR-58 Filter/ Regulator Unit Positive Pressure M Range Precision spec. and
High Performance spec. Filter
FR-59 Filter/ Regulator Unit Positive Pressure H Range Standard spec.
FR-60 Filter/ Regulator Unit Positive Pressure H1 Range Standard spec.
FR-61 Filter/ Regulator Unit Negative Pressure V Range Standard spec.
FR-62 Filter/ Regulator Unit Negative Pressure V Range Precision spec. P-200

12
OUTLINE TESTER SPECIFICATIONS
■TESTER SPECIFICATIONS
Testing Method Work/ Work Comparison, Work/ Master Comparison, Work/ Fixed
Master Comparison, Differential Pressure Method Air Leak Tester
Volume Testing By employing a flow master, Volume testing and calibration can be
done according to actual leak standards.
Differential Pressure
Sensor
VR-55A（2CD）F.S.2000Pa/5V
Work Side Accuracy±1% , Master Side Accuracy±2%
V Range -101 kPa Accuracy±2％FS
UL Range 50 kPa Accuracy±2％FS
L Range 100 kPa Accuracy±2％FS
M Range 1 MPa Accuracy±2％FS
H Range 1 MPa Accuracy±2％FS
Applied Pressure Sensor
(Semiconductor sensor)
H1 Range 2 MPa Accuracy±2％FS
Work Side Volume V,UL,L,M Range Approx. 4.1 ml
H1 Range Approx. 3.6ml
Calibration port about
4.2ml.
Master Side Volume V,UL,L,M,H Range Approx. 3.8ml
H1Range Approx.3.2ml
Master Tank Inner volume 28ml (Hi Range Pressure is not included.)
Testing Sensitivity Standard work of 50ml used for Leak Experiment
Result: within ±5% 1ml/min.
Air Pilot Drive Valve Driving Pressure 300～400kPa
Display
LCD Display (with CFL backlight)
Indication Dot Numbers 128×48
Effective Indication Measurement W90mm×D36mm
Group Setting 0～15 group（16ch total）
External Input / Output
REMOTE 50pin(ExternalControlSignal)
APU SIGNAL 8pin (APU Control Signal)
EXT VALV SIGNAL 34pin (Externally Mounted Option Valve Signal)
RS-232C 9pin(DataOutputSignal)
Operation Temperature/
Humidity Range 0～40℃, 45～85%RH with no condensation
Power Supply Voltage AC90～110V, 200～240V
Consumption Current Approx. 100VA
Air Specifications
Please supply clean , stable , and dry air
Recommended Condition: Based on JISB8392-1:2000
Compressed Air Quality Class1,3,1
Class Article Reference
1 Maximum Particle Diameter 0.1μm
3 Minimum Pressure Dew-point -20℃
1 Maximum Oil Content 0.01mg/mm3
External Dimensions W162×H256×D345 (Not including protruding objects)
For External Dimension Diagram, please refer to page 119.
Weight Approx. 7.5kg

13
OUTLINE EXCLUSIVE OPTION
■ PNEUMATIC REGULATOR (APU) SPECIFICATIONS
Please refer to the following when connecting the APU to be used in combination with the
FL-601.
ＡＰＵ－➊ ➋－(➌)－➍－➎－➏
➊ Configuration
Applicable work volume guidelines*1
Symbol Configuration
V *2 UL L M *3
70W φ70 mm ～200ml ～2L ～2L
90W φ90 mm ～400ml ～2L ～4L More than 2L
130W φ130 mm More than More than 2 More than 4
*1 These values are only to be used as guidelines. Please use these as a reference, as the actual values
will vary depending on the margin degree of the cycle time, the source pressure (including the primary
pressure decrease valve) supply capacity, the test pressure and the work structure, etc.
*2 Do not select the APU-70W series for small pressure applications (less than -30kPa,) even for works
with a small volume.
*3 Select neither APU-70W series nor 1% sensor in case of using the low pressure (less than 100kPa)
and middle pressure by switching even in M range.
➋Pressure Control Range
Symbol Configuration
Note
P Positive
V Negative
The FL-601 will automatically control this range by simply
connecting the cables.
➌Pressure Range（kPa）
Symbol Pressure Range Note
－100 V 70W,90W,130W only
+20 UL 90W,130W only
+100 L 70W,90W,130W only
+700 M 70W,90W only
➍APU Specifically for Use with Leak Testers
Symbol Note
X005
This model is specifically for use with air leak testers. The charge pressure
characteristics are different from standard APUs. Please use caution when
purchasing this model separately or when replacing parts. (Other functions,
including its control, are consistent with other models.)
➎Sensor Models and Accuracy
S
y
mbol Model
A
ccurac
y
C SX-100D ±0.15% of F.S.
E SX-34 ±1.0% of F.S.
➏APU Control Cable
Symbol Length of Cable Note
1.5 1.5m Standard Attachment
3 3.0m Option
*This cable is used to connect the FL-601(APU SIGNAL) to the APU (INPUT)
*Refer to the APU series catalogue or user manual for common specifications other than those
described here.

14
OUTLINE EXCLUSIVE OPTIONS
■EXHAUST / PRESSURE BYPASS UNIT (EBU-600 / CBU-600) MODELS AND SPECIFICATIONS
EXHAUST BYPASS UNIT
EBU-600➊－➋
➊Range
Symbol Pressure Range REMARKS
V -5 ～-90 kPa TEST.SUP
C 10～700 kPa AIR IN
➋ Bypass Unit Cable
Symbol Cable Length REMARKS
1.5 1.5m ACCESSORY ITEM
3 3.0m OPTIONAL ITEM
PRESSURE BYPASS UNIT
CBU-600➊－➋
➊Range
Symbol Pressure Range REMARKS
C 10～700 kPa AIR IN
➋ Bypass Unit Control Cable
Symbol Cable Length REMARKS
1.5 1.5m ACCESSORY ITEM
3 3.0m OPTIONAL ITEM

15
OUTLINE ADDITIONAL EQUIPMENT
■ADDITIONAL EQUIPMENT
PRODUCT NAME MODEL Remarks
BL－80RSⅡPrinter Body
AR305/1.5 RS232C Straight Cable 9P female - 25P male
1.5m
UR－121+NC－LSC01 BL-80RSⅡBattery + Battery Charger
Printer
BL－100W+AC－100J BL-80RSⅡAC adapter
FE－20 (Vacuum)
FE－20C (Positive)
EBU－600 V－□(Vacuum)
Exhaust Bypass Unit
EBU－600C－□(Positive)
Charge Bypass Unit CBU－600C－□(Positive)
Please refer to page14 for
ordering details/specifications.
Flow Master FFM－100 Please specify your test pressure and leak rate when
you fill out your purchase order.
Master Tank capacity:28ml
Manual Calibrator CAL－0.1 0.1ml F.S. (R 1/8)
Manual Calibrator CAL－1.0 1.0ml F.S. (R 1/8)
Manual Calibrator CAL－5.0 5.0ml F.S. (R 1/8)
Remote Control Dial
Regulator 2302－3C Large Leak Source Pressure Regulator
APU－70W
APU－90W
Pneumatic Regulator
APU－130W
Please refer to page 13 for details and specifications
on our various models.
Pressure Switch PS01
Pressure Switch for Negative Pressure
Sensitivity ±3%F.S.
Pressure Preset Capacity: -101kPa ～0 kPa
PS02
Pressure Switch for Positive Pressure
Sensitivity ±3%F.S. Pressure Preset
Capacity: 0 kPa ～100 kPa
PS03
Pressure Switch for Positive Pressure
Sensitivity ±3%F.S. Pressure Preset
Capacity: 0 MPa ～0.97 MPa
Air Tank Tank volume 20 Liters
(Works up to 2L)
Air Tank Tank volume 38 Liters
(Works at least 2L)
Tank to stabilize the source pressure

16
OUTLINE ADDITIONAL EQUIPMENT
MEMO

17
PRINCIPLE

18
PRINCIPLE WHAT IS AN AIR LEAK TESTER?
■What Is Air Leak Testing?
□The Importance of Leak Testing and the Permissive Leak Rate
A “leak” in a product may cause a variety of problems depending on the industry. For example, the existence
of a leak in gasoline valves may cause fire or explosion, while a leak in a water valve may cause corrosion
and be responsible for performance deterioration. From these examples, we can conclude that every
product would, under ideal circumstances, not leak or have “zero” leak.
Although “zero” leak is highly desirable, it is nearly impossible, or very difficult to achieve, therefore it
becomes necessary to determine the most reasonable leak rate (permissive leak rate) while foreseeing
potential damages and effects that may originate from a leak problem. This permissive leak rate differs from
product to product, and industry to industry.
For example, a leak in a gasoline valve may cause a fire or explosion, making it necessary to define what a
non-risky leak rate is. In other words, how much gas will presumably evaporate into the atmosphere
before it becomes dangerous?
For water valves, it is necessary to determine the permissive leak rate that will not affect product
performance not only for a short time but also for the lifetime of the product.
Generally speaking, the degree of leak detection and the cost of leak inspections will have an inverse
proportional relationship. The pursuit of “zero” leak often results in production cost increases and often
prolongs production time. Thus, the permissive leak rate is determined based on the function and
performance characteristic of the inspected product and the amount of leak inspection costs that
manufacturers are allowed to invest.
□Leak Tester Detection Limits
FUKUDA Air Leak Testers are designed to use compressed air as its testing media in order to detect a small
quantity of pressure alteration (caused by a leak in the work,) to automatically evaluate the existence of a
leak. Considering various restrictions, the minimum detection sensitivity of the leak is roughly expressed as
follows.
For more detailed information, refer to the following pages.
Minute leak detection sensitivity (ml/min) =
(
)
Time(min) 10mleWork volum -3
×

19
PRINCIPLE WHAT IS AIR LEAK TESTING?
■What Is Air Leak Testing?
Some traditional methods of leak testing employed by manufacturers included the hydraulic submersion
method, which involved immersing work parts into water to observe bubble formation, and the soap water
application method, which consists of applying soap water on the surface of the work part in order to observe
bubble formation. Although these methods were commonly practiced, they most often received a great deal
of interference from outside sources and the results were mostly determined by the subjectivity and
experience of the operator. These methods also required a long processing time and evaluation was
terminated if bubbles were not found during this period. Additionally, the care required to properly execute
these methods, such as cleaning and drying, caused many manufactures unnecessary problems and
headaches.
The Helium leak testing method is another method that some manufacturers have employed. This method
is costly in that not only is the initial investment of having to purchase the Helium leak tester expensive, but
running costs and maintenance become prohibitive.
FUKUDA Air Leak Testers use an original, highly sensitive differential pressure sensor, which allows
testing minute leaks in a shorter period of time. By using air as its testing media, not only can one expect
high accuracy and sensitivity but also a reduction in running costs and the elimination of post-processing.
Different leak testing conditions and requirements can be easily set according to the test products and
setting definite conditions with numeric values enables automated leak testing with consistent objectivity.
The operation of this equipment can also be controlled by external signals, allowing you to extract the testing
results, thereby allowing full automation of the production process and a subsequent reduction in labor
costs.
□Leak Testing Principles
と
Please consider a balance scale used for
measuring small amounts of medicine.
The balance scale is an instrument used to
precisely measure the weight of a certain
value by comparing the object against a
reference weight.
Fukuda air leak testers use this same
underlying principle for our testing method.
When the test is started, the same amount
of air pressure is injected into the master
and the work. The tester then examines the
leak amount by observing a change in the
balance over a certain period of time.
If the test part has no leak, the charged
pressure amount will not alter and the
balance between the reference value and
test parts will be maintained. However, if
a leak is present, the pressure within the
test part will decline as time lapses, causing
a pressure imbalance between the two.
The speed with which the imbalance
develops depends on the size of the leak.
Referenc
e
weight
(master) Medicine
Referenc
e
part
s
(with no master)
Work
Measuring medicine using a balance scale
Apply the same pressure to both and
observe the pressure balance
Imbalance occurs with presence of a leak