Magnaflux Y7 User manual

Operating
Manual
Y7 Electromagnetic Yoke
Faraday Road, South Dorcan Industrial Estate, Swindon, SN3 5HE, UK
Telephone: + 44 (0)1793 524566 Fax: [phone]
Email: sales.eu@magnaflux.com Web: eu.magnaflux.com
Bahnhofstr 94-98, 73457 Essingen, Deutschland
Telephone: [phone] Fax: [phone]
Email: sales.de@magnaflux.com Web: eu.magnaflux.com/de

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4.2 ACCESSORIES
L10 MAGNETISING COIL
Developed for testing shafts, spindles and similar
parts.
• Ideal for inspecting for transverse cracks
• Components are magnetised and demagnetised
with the same coil
• 110V operation
• Suitable for wet and dry Magnetic Particle Inspec-
tion (MPI) methods
• Footswitch provides continuous control
Part number: 008C020
CERTIFIED TEST WEIGHTS
AC Test Weight (4.5Kg) Part number: 026T018B
DC Test Weight (18Kg) Part number: 026T018A
Certificate of Conformity
Y7 Yoke Serial Number:
Date of Manufacture:
Certified that the above item conforms to and meets the require-
ments of the following:
EC Directives
2006/95/EC
2014/30/EC
Specifications
ASME V ART7
ASTM E709
ASTM E1444
EN-ISO 9934-3
MIL-STD-271F(SH)
Certificate is issued under the auspices of the Equipment Product
Manager:
Magnaflux (A Division of ITW Ltd),
Faraday Road, South Dorcan Industrial Estate, Swindon, SN3 5HE, UK
Tel: [phone] Fax: [phone]
Email: sales.eu@magnaflux.com www.eu.magnaflux.com

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4. RECOMMENDED PRODUCTS
4.1 CHEMICAL CONSUMABLES
PREPARED INKS
Flash point
(PMCC)
Viscosity
(mm2/s)
Density
(g/cm3)
Particle
size (µm)
Settlement
volume
OIL-BASED (high-flash, low-odour kerosene base)
410HF 93 oC 3.45 0.81 7 - 25 0.12% V/V
14HF 93 oC 3.45 0.81 2 - 25 0.25% V/V
7HF 93 oC 3.45 0.81 0.6 - 2.5 2.5% V/V
WATER-BASED
WB-12 N/A N/A 1.2 7 - 9 0.1 - 0.4 ml
MF-655 WB N/A N/A 1.1 3 - 5 0.13 - 0.21 ml
DRY POWDERS
MAGNAVIS dry powders have closely-controlled particle size and shape, and
come in a range of colours to give the best possible contrast on a wide variety
of finishes. For best results, the powder should be cloud-applied near the surface
while the current is flowing.
Maximum working temperatures:
MAGNAVIS®1 Grey 315 oC
MAGNAVIS®8A Red 175 oC
CONTRAST PAINT
Use MAGNAVIS®WCP-2 White Contrast Paint when the contrast between the test
surface and the ink/powder is not clear enough for inspection. Apply a thin coating
for WCP-2 to the surface prior to testing.
SPECIFICATIONS
MAGNAGLO and MAGNAVIS concentrates, prepared inks and dry powders meet
the requirements of ASTM E1444. Our oil-suspended inks and concentrates meet
AMS specifications, plus appropriate industrial and Government specifications,
Certifications are available on request.
1. IMPORTANT SAFETY INFORMATION
DANGER TO PERSONS WITH CARDIAC PACEMAKERS
MAGNETIC FIELD RISK
Persons susceptible to strong magnetic fields, including those
with pacemakers, are advised not to use or approach this
equipment without seeking professional advice. Magnetic
fields can, in some cases, interfere with cardiac pacemakers
so if you wear a pacemaker, you must get a clearance certifi-
cate from your doctor before using this yoke.
DANGER OF ELECTROMAGNETIC FIELDS
Strong magnetic fields can have serious health eects.
DO NOT USE THIS YOKE:
• if you have a pacemaker, insulin pump or other implanted
device.
• if you have any metallic implants.
• if you are pregnant.
• for more than 8 hours a day.
• DO NOT smoke while performing Non Destructive Testing (NDT).
• DO NOT operate the Y7 Yoke for longer than 2 minutes ON followed by 2
minutes OFF.
• If the Yoke becomes too hot to hold in your bare hand, this is a sign that the duty
cycle has been exceeded. Stop inspecting and wait for the Yoke to cool before
continuing.
• DO NOT use any means to permanently operate the Yoke switch.
• DO NOT use the power cable to pull, lift or carry the equipment.
• When the Yoke is switched OFF, the magnetic attraction to the tested
component will be weakened and either the part or the Yoke could fall and
cause injury.
• DO NOT change the AC/DC selector switch while the current is ON.
• DO NOT operate from a DC power source.

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3.1 COMPONENTS AND OPERATING ELEMENTS
Area of increased exposure
1.1 SAFETY DISTANCES
The regulations below recommend that, while the yoke is in use, all personnel
(other than the operator) should maintain the following minimum safety distances
from the yoke:
• people without body-implanted devices: 20cm / 8”
• people with body-implanted devices (e.g. pacemakers): at least 5m / 16ft.
Exposure to electromagnetic fields is highest within a 0.5m radius of the yoke.
1.2 FLAMMABILITY
The Y7 Yoke is designed to be used in conjunction with appropriate chemicals as
a means of non-destructive testing (NDT) for defects, such as cracks, on a wide
range of manufactured components. Some chemicals may produce a flammable
atmosphere at the point of use so it is important that the testing is carried out in a
well-ventilated place and that all sources of ignition are excluded.
Good-quality NDT chemicals, such as Magnaflux magnetic inks and powders, are
formulated to minimise the risk of a flammable atmosphere when correctly used.

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1.3 ELECTRICAL
Ensure that the protective conductor (earth) is continuous from the Y7 laminations
through suitable connections to the electrical supply.
Recommendations:
• Use a Residual Current Circuit Breaker (RCCB) or Earth Leakage Circuit Breaker
(ELCB).
• If the switch area of the Yoke becomes wet with kerosene or water, disconnect
it from its supply until the area has dried.
• In damp conditions, use a 100V Yoke operated from a supply that is centre-
tapped to earth (55V-0-55V)
• If the Y7 shows signs of malfunctioning, or if cracks appear in the casing, take
the Yoke out of service immediately and have it examined by a qualified
electrician. Cracking is usually caused by dropping the Yoke or by twisting the
articulated legs.
• Do not change the AC/DC selector switch with the unit on.
• Do not operate from a DC power source.
• Do not attempt any repairs on this Yoke. The units are sealed and should be
returned to the factory.
• Wire colours (115/230V) – Brown-Live, Blue-Neutral and Green/Yellow-Earth
In many countries, it is a legal requirement that the electrical safety of equipment is
checked periodically, commensurate with use, but at least once a year. The basic
tests required are to check the condition and eectiveness of the electrical
insulation and the continuity of the protective conductor (earth). These tests can be
performed using a Portable Appliance Tester (PAT) or Portable Appliance Checker
(PAC).
3. TECHNICAL SPECIFICATION
Part number 001Y018
AC voltage ± 10% (V) 230
Frequency (Hz) 50/60
Supply current (A) (intermittent*) in air 2
Recommended supply fuse (A) 3
Weight (kg) lifted at 100 mm pole spacing AC: 4.5 DC: 13.5
Operating environment: temperature 0 - 40oC
Operating environment: relative humidity 10 - 95% non-condensing
* Maximum continuous duty: two minutes ON and two minutes OFF.

2. OPERATING THE Y7 YOKE
2.1 PRINCIPLE OF OPERATION
When the Yoke is connected to a suitable power source, depressing the ‘Push to
test’ switch creates an intense magnetic field between the Yoke legs. As the Yoke
is applied to a steel plate, the magnetic circuit is closed, and the magnetic field
enters the plate between the legs of the Yoke at and near the surface. A surface
crack across this field cuts the magnetic circuit, the two sides of the crack become
opposite poles of a magnet and a leakage field occurs in the air above the crack.
Magnetic particles are attracted by this leakage field and mark its location.
2.2 SAFE USE OF THE YOKE
Our yokes manufactured to the highest technical standards. You can ensure safe
operation of your yoke by observing general safety and accident prevention regu-
lations, including the advice outlined below.
Before using the Yoke:
• Familiarise yourself with thE yoke’s construction and method of operation. If
necessary, contact the manufacturer - Magnaflux GmbH - for instruction/training.
• Ensure it is physically undamaged.
• Ensure the cable is free from cuts which expose the wiring.
• Tighten the articulated joints if they are excessively loose.
During use:
• Follow the operating instructions carefully.
• Observe the safety distances (see section 1.1) and time limit for usage.
• Wear appropriate personal protective equipment to protect yourself from over
exposure to electromagnetic fields.
• Do not allow untrained personnel to operate the yoke; improper use of the
yoke can be hazardous to health.
• Only allow authorised personnel who are aware of the potential dangers of
electromagnetic exposure into the areas where the yoke is being used.
• Do not attempt to repair or rebuild the yoke unit.
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2.3 INSTRUCTIONS FOR USE
1. Adjust the leg spacing to 125 - 175mm and place the Yoke firmly on the work
piece, ensuring the best contact possible, with the suspected defect at right
angles to the poles. If the direction of the potential defect is not known, two
inspections of the area should be made, turning the Yoke approximately 90° for
the second inspection.
2. With the selector switch in either the AC or DC position, depress the test switch
to energise the Yoke.
3. Apply the magnetic ink/powder to the area between the Yoke legs and inspect
closely for cracks or defects. The current should remain ON (continuous
method) to ensure maximum sensitivity.
4. Repeat the process until the entire area of the part is inspected.
5. Demagnetisation: With the Yoke in the AC mode, place the part across the
poles and, whilst the current is flowing, withdraw the part from the field to a
distance of at least 0.75m before turning o the magnetising current.
Dierent parts and surfaces will dictate the best magnetising current, current magni-
tude, particle application and testing procedures to achieve good inspection results.
Always use the lowest magnetising current necessary to provide distinct indications,
as excessively high fields may magnetically saturate the test piece and cause a
‘masking eect’, hiding the defects.
2.4 MAGNETISING FIELD SELECTION
AC magnetisation
This induced field only detects surface cracks. It is particularly useful for inspecting
thick and irregular sections for surface defects. Best results are usually obtained
using the drymethod.
Pulsed DC magnetisation
This induced field penetrates the work piece and detects both surface and slightly
subsurface cracks. Best results are usually obtained using the wet method.