Operating Manual

Y7 Electromagnetic Yoke

Faraday Road, South Dorcan Industrial Estate, Swindon, SN3 5HE, UKTelephone: + 44 (0)1793 524566 Fax: +44 (0)1793 490459 Email: sales.eu@magnaflux.com Web: eu.magnaflux.com

Bahnhofstr 94-98, 73457 Essingen, Deutschland Telephone: +49 (0) 7365 81-0 Fax: +49 (0) 7365 81-449 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: 026T018BDC 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/EC2014/30/EC

Specifications

ASME V ART7ASTM E709ASTM E1444EN-ISO 9934-3MIL-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: +44 (0)1793 524566 Fax: +44 (0)1793 490459 Email: sales.eu@magnaflux.com www.eu.magnaflux.com

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4. RECOMMENDED PRODUCTS

4.1 CHEMICAL CONSUMABLES

PREPARED INKSFlash 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 POWDERSMAGNAVIS 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 oCMAGNAVIS® 8A Red 175 oC

CONTRAST PAINTUse 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.

SPECIFICATIONSMAGNAGLO 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 PACEMAKERSMAGNETIC FIELD RISKPersons 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 FIELDSStrong magnetic fields can have serious health effects.

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 ELECTRICALEnsure 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 effectiveness 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 OPERATIONWhen 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 YOKEOur yokes manufactured to the highest technical standards. You can ensure safeoperation 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 off the magnetising current.

Different 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 effect’, hiding the defects.

2.4 MAGNETISING FIELD SELECTION

AC magnetisationThis 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 magnetisationThis induced field penetrates the work piece and detects both surface and slightly subsurface cracks. Best results are usually obtained using the wet method.