where expertise comes together - since 1996 -

The Largest Open Access Portal of Nondestructive Testing (NDT)

Conference Proceedings, Articles, News, Exhibition, Forum, Network and more

where expertise comes together
- since 1996 -

Zawada NDT
Suppliers of instruments to test steel wire ropes in-situ, using magnetic, non-destructive method.

3019 views
Technical Discussions
Engkus Kusnadi
NDT Inspector, -
PT SEAMLESS PIPE INDONESIA JAYA, Indonesia, Joined Apr 2007, 5

Engkus Kusnadi

NDT Inspector, -
PT SEAMLESS PIPE INDONESIA JAYA,
Indonesia,
Joined Apr 2007
5
05:20 Mar-03-2009
Magnetic field of Circular magnetization

Dear All

Why magnetic field of Circular magnetization by shootin rod weak and take time appears on Burmah Castrol
Stip than Longitudinal Magnetization by Coil.

Regards,

Kusnadie

    
 
 
mandar
mandar
07:38 Mar-05-2009
Re: Magnetic field of Circular magnetization
In Reply to Engkus Kusnadi at 05:20 Mar-03-2009 (Opening).

Dear kusnadie ,

your question is not clear to me as magnetization by central conductor and by coil are two entirely different magnetic fields please give more information about part geometry and methods of magnetization used

    
 
 
Kusnadie
Kusnadie
01:00 Mar-06-2009
Re: Magnetic field of Circular magnetization
In Reply to mandar at 07:38 Mar-05-2009 .

Dear Mandar,

Thank you,
During conduct inspection on seamless pipe by Wet Magnetic Particle Inspection i use Burmah castrol strip to check sufficiency of magnetic field. First time the pipe magnetize by shooting rod to produce circular magnetization then verify sufficiency of magnetic field by Burmah Castrol Strip but indication get weak and take time to appears than longitudinal field by coil on 2nd step. Whereas all facility already on good condition and calculation Formulas
as per ASTM.

Regards,

Kusnadie

    
 
 
Andreas
NDT Inspector, Specially in the oilfield
Tuboscope Vetco(Deutschland)Gmbh, Germany, Joined Oct 1999, 126

Andreas

NDT Inspector, Specially in the oilfield
Tuboscope Vetco(Deutschland)Gmbh,
Germany,
Joined Oct 1999
126
15:28 Mar-09-2009
Re: Magnetic field of Circular magnetization
In Reply to Engkus Kusnadi at 05:20 Mar-03-2009 (Opening).

The formula you refering to is for longitutinal mag not for circular.Have a look into the ASTM E-709.
There are also some "rules of thumb" if not specified by the specification you working to.
For direct cirular mag use 300 - 800 amps per inch diameter when using a central conductor.
By using a prod use use 90 - 115 amps per inch prod spacing for parts up to 3/4" thickness.For thicker parts use 100- 120 amps per inch spacing.
This are only estimates better to verify the field my measurement.


regards

andreas

    
 
 
Tim Brown
Tim Brown
20:32 Jul-07-2010
Re: Magnetic field of Circular magnetization
In Reply to Andreas at 15:28 Mar-09-2009 .

The circular field that is created with the central shooting rod doesn't leak much from the pipe, especially if the surface condition is good. By comparison, the longitudinal field created in the pipe by the encircling coil will have a very strong leakage field that can easily be detected with a simple field indicator.

The use of Burmah Castrol strips to verify the strength of a residual circular field in a pipe is questionable and not reliable.

    
 
 
Andreas
NDT Inspector, Specially in the oilfield
Tuboscope Vetco(Deutschland)Gmbh, Germany, Joined Oct 1999, 126

Andreas

NDT Inspector, Specially in the oilfield
Tuboscope Vetco(Deutschland)Gmbh,
Germany,
Joined Oct 1999
126
21:51 Jul-07-2010
Re: Magnetic field of Circular magnetization
In Reply to Tim Brown at 20:32 Jul-07-2010 .

Hallo Tim ,
when you have circular field there will nearly no flux leakage at the surface. To prove the field with the strip ,you need to find a dent etc at the surface and place the strip there.
You will see than that the strip works.

Andreas

    
 
 
Jim Draper
Consultant, ASNT Level III MT PT RT VT
Draper NDT, USA, Joined Jul 2009, 99

Jim Draper

Consultant, ASNT Level III MT PT RT VT
Draper NDT,
USA,
Joined Jul 2009
99
00:58 Jul-08-2010
Re: Magnetic field of Circular magnetization
In Reply to Andreas at 21:51 Jul-07-2010 .

I like to use QQIs or a hall effect gauss meter to verify the strength of the circular field. Formulas do not take into account the permeability of the material. Another thing I have done is, use a scribe to scratch a line running parallel with the part. This should show that you have established a circular field. It also takes more amps to produce a sufficient shot using contacts than is does when using a coil.

    
 
 

Product Spotlight

Spot weld inspection with Phased Array – PHAsis.one

The first PAUT spot weld inspection device offering a physical resolution of the spot weld diamete
...
r better than 0.35mm. Precise: more than 700 real UT measurements per spot weld. Easy to go: minimal training required due to the user friendly inspection software. Be sure: safe evaluation due to the imaging result display and automated creation of an evaluation proposal for the spot weld quality.
>

Immersion systems

ScanMaster ultrasonic immersion systems are designed for high throughput, multi shift operation in a
...
n industrial or lab environment. These fully integrated systems provide various scanning configurations and incorporate conventional and phased arrays technologies to support diverse applications, such as inspection of disks, bars, shafts, billets and plates. All of ScanMaster immersion systems are built from high accuracy scanning frames allowing for scanning of complex parts and include a multi-channel ultrasonic instrument with exceptional performance. The systems are approved by all major manufacturers for C-scan inspection of jet engine forged discs. Together with a comprehensive set of software modules these flexible series of systems provide the customer with the best price performance solutions.
>

Semi-Automated Phased Array Immersion System for Small Composite Parts

Turn-key semi-automated system as an improved and affordable solution for inspection of small comp
...
osite parts. Includes support table, immersion tank, scanner, PA instrument, PC, Analysis software, database, wedge management and other options.
>

Varex Imaging Large Field of View (FOV) Digital Detector Arrays (DDAs)

A larger FOV DDA can reduce the space and volume of the X-ray inspection system on the factory floor
...
, enable faster scanning times, better throughput and better resolution images at a lower dose. Customers can also save time and money. With these benefits in mind, Varex Imaging has designed a family of large FOV detectors (4343HE, XRD 1611, 4343DX-I, 4343CT) for our industrial imaging customers.
>

Share...
We use technical and analytics cookies to ensure that we will give you the best experience of our website - More Info
Accept
top
this is debug window
s