INDEX 1.INTRODUCTION 2 2.GENERAL DESCRIPTION 3 3.FEATURES 3 4.PRINCIPLE OF OPERATION 4 5.MAGNETIZING FIELD SELECTION 4 6.OPERATING INSTRUCTION 5

Size: px

Start display at page:

Download "INDEX 1.INTRODUCTION 2 2.GENERAL DESCRIPTION 3 3.FEATURES 3 4.PRINCIPLE OF OPERATION 4 5.MAGNETIZING FIELD SELECTION 4 6.OPERATING INSTRUCTION 5"

Doreen Alexander
5 years ago
Views:

1 INDEX S.NO NO. PAGE 1.INTRODUCTION 2 2.GENERAL DESCRIPTION 3 3.FEATURES 3 4.PRINCIPLE OF OPERATION 4 5.MAGNETIZING FIELD SELECTION 4 6.OPERATING INSTRUCTION 5 7.TECHNICAL SPECIFICATION 6 8.MAINTAINANCE 7 9.PRECAUTIONS 8 10.TROUBLE SHOOTING 9 11.SPARE PARTS LIST WIRING DIAGRAM 11 1

1.INTRODUCTION This manual containts the necessary information to acquaint the operation of the SM-7 Model AC/HWDC Electromagnetic Yoke with its capability and

the purpose of this manual is to furnish the operator with a functional knowledge of the operation and to make understand the safety precautions which should be

2 1.INTRODUCTION This manual containts the necessary information to acquaint the operation of the SM-7 Model AC/HWDC Electromagnetic Yoke with its capability and operation.the purpose of this manual is to furnish the operator with a functional knowledge of the operation and to make understand the safety precautions which should be applied during operation and to make understand the safety precaution which should be applied during operation and maintenance of the equipment. PERSONNEL S FAILING TO COMPLETELY READ AND UNDERSTAND THESE INSTRUCTIONS BEFORE PROCEEDING WITH THE INSTALLING OPERATION OR MAINTENANCE OF THIS EQUIPMENT RUNS THE RISK OF INJURY. 2

3 2.GENERAL DESCRIPTION The light weight electromagnetic yok is the ideal tool for detection of surface or sub-surface cracks and flaws in any ferromagnetic material no other low cost portable equipment offers such versatility in magnetic particle inspection. Fast and simple to operate,it is widely used within either dry or wet method fluorescent or non-fluorescent magnetic powders,in the testing of welds,automotive or rail road components,machine parts,steel or grey iron castings,forgings and in plant inspection maintainance and repair.it is supplied in a carrying case for storage and transport. 3.FEATURES Choice of constant level AC or variable intensity pulse HWDC current for surface or sub-surface flaw detection. Solid state circuitry for infinitely variable ( stepless ) potentiometeric adjustment of DC magnetic field. Articulated legs to suite differing components contours,interpole distance adjustable from 0 to 300mm Low power consumption.current drawn at 220 V,1 phase supply is only 2 Ampere Extremely strong and intense magnetic field for superior sensitivity Portable and light weight Can be used for AC demagnetization too No risk of sparking or hot spots on the job No current flows through the component being tested 3

4 4.PRINCIPLE OF OPERATION When the yok is energized by connecting to proper power supply,depressing the push to test switch creates an intense longitudinal magnetic field between the legs.the resultant field can best be described as a multiplicity of invisible line of force extending across the gap between the legs.as the yok is applied to a ferro magnetic material,the magnetic circuit is closed and the field enters the part making its passage between the legs and at below the surface.a crack across this field cuts magnetic circuit,the two side of crack become opposite pole of magnet and a leakage field occurs in the air above the crack.magnetic particles sprinkled on the surface are attached by this leakage field and indicate the location of the flaw.for best results,the yoke is positioned such that the magnetic field created between the legs is transverse to the direction of suspected cracks. 5.MAGNETIZING FIELD SELECTION AC MAGNETIZATION The induced field is surface field which only detect surface flaws.it is particularly useful for inspecting thick and irregular sections for surface defects.best results are abtained with dry method. HWDC(PULSED)MAGNETIZATION 4

5 The induced field creates the pulsating magnetic field which penetrates the work piece and detects both surface and sub-surface flaws.the pulsing of the field improves particle mobility & sensitivity and hence,this mode can be used for both dry and wet method.wet method gives best results. 6.OPERATING INSTRUCTIONS MAGNETIZATION: Adjust the legs to a spacing of 120 mm to 180 mm and place the yoke firmly upon the work piece by securing best possible contact with the suspected defect transverse to the magnetic field between the legs.with the selector switch in either the AC or DC position:press the test switch to energize the yok and lightly dust the magnetic particles (Dry method) or flow the magnetic particle suspension (wet method) over the area being inspected.as an example,when testing for longitudinal cracks in a butt weld the yoke would be positioned so that the legs straddle the weld.if the direction of a possible defect is not known,two inspections should be made in such a possible defects is not known,two inspections should be made in such area,turning the yoke approximately 90 for second inspection.use the AC mode for surface flaws detection and DC for slightly sub-surface inspection. 5

6 In the dry method using the power blower bulb,the area between the legs of the yoke is dusted lightly with Magnetic powder and inspected closely for flaws or other defects.current should remain ON (continuous method).this process is repeated until the entire area of part is inspected. The Continuous method should always be used for maximum sensitivity.always use the lowest magnetizing current necessary (in DC) to produce distinct indications.avoid excessively strong fields which may magnetically saturate the test piece and cause Making effect or Back ground which will interfere with flaw indication. DEMAGNETIZATION: The SM-7 yoke can usually be used to abtain a satisfactory level of demagnetization.with the equipment in AC mode place the part across the pole and while the current is fllowing slowly withdraw the part from the field to a distance of the least 60 cm before turning off the magnetizing current. 7.TECHNICAL SPECIFICATIONS Specification Meets requirements of ASTM E Input supply 220 V, 50 Hz, 1 Ph Input Current 2 Amps Distance across the pole mm Magnetic Field AC-Constant Level, DC- Pulsed, 6

7 Infinitely variable Flux Density Approx.10,500 Lines of force / cm² at 100 mm pole spacing Pulling Capicity Approx.27 Kg (60 Lbs) in DC mode at 100 mm spacing. 5 Kg (11 Lbs) in AC mode at 100 mm spacing. Yoke Weight 3.5 Kgs Approx. Duty Cycle 23% (3 sec on followed by 10 sec Off Controls On / Off Switch AC / DC Switch DC Field intensity Potentiometer 8. MAINTENANCE 7

8 A periodic visual inspection of the interior electrical compound is highly recommended.such an inspection can preclude operational malfunctions and components failure.disconnect the supply before gaining access to the interior of the magnetic yoke. Check all the wiring for the discoloration,burnt insulation and loose connections.ensure the cable are free from cuts which expose the wiring. Prevent the yoke body and its interior from wet particles and liquids.liquid bath or wet magnetic particles if peeped inside the body can damage the yoke components and can affects its working efficiency. The equipment should be cleaned with a soft brush to loosen stubborn particles with care being exercised to avoid damaging delicate electrical leads. After every six months yokes should be checked for its pulling capacity.it should lift minimum 4.5 KG at 100 mm spacing for AC selection and 22.5 KG at 100 mm spacing for DC Selection. When equipment is not in use keep it at safe place,probably in its carrying case. 8

9 9. PRECAUTIONS Do not operate the SM-7 yoke for Longer than 3 seconds ON followed by 10 seconds OFF,ie. 23% duty cycle continuously. DO NOT energize the yoke for more than the duty cycle recommended.if the yoke is too hot to hold in the bare hand it is a sign that the duty cycle has been exceeded.wait for the yoke to cool before continuing. DO NOT connect the yoke to a battery for portable work. DO NOT change the AC / DC selector switch while the unit is energized. Ensure that there is firm contact between test piece and yoke legs for better indications of the defects and less noise. DO NOT open the yoke handle and change any settings on the PCB. DO NOT drop the yoke from a height or subject th handle to any service impact. Ensure that yoke is connected to earth through proper 3 pin plug for operator safety. DO NOT replace any parts with other than those recommended by SUPERMAG. DO NOT smoke while performing NDT. DO NOT use the supply cable to pull,lift or carry the equipment. 9

10 10.TROUBLE SHOOTING PROBLEM A)Unit does not operate in AC/DC MODE POSSIBLE CAUSES 1) Defective push button AC switch 2) Open wire in power cord or plug 3) Open coil wire B) Unit will not run off 1) Fused push-to-test switch. 2) Jammed push-to-test switch C) Unit over heats 1) Defective circuit board 2) Shorted coil 3) Enhanced Duty Cycle D) Unit does not operates in AC 1) AC/DC switch contacts open 2) Open wires in PCB or wiring E) There is no Control in DC Mode 1) Faulty Level control potentiometer 10

11 Do not replace any parts with other than those Recommended by SUPERMAG 11.SPARE PARTS LIST S.NO. PART NAME 1. PCB ASSEMBLY 2. PUSH TO ON SWITCH 3. AC / DC SWITCH 4. COIL WINDING ASSEMBLY 5. LEG ASSEMBLY 11

12 12

13 13

ATD AMP Variable Speed Reciprocating Saw Owner s Manual

ATD AMP Variable Speed Reciprocating Saw Owner s Manual ATD-10535 7 AMP Variable Speed Reciprocating Saw Owner s Manual Manufactured in China To ATD Tools, Inc. Specifications TECHNICAL SPECIFICATIONS Voltage: 120V Frequency: 60Hz Power input: 7 Amps No load