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 -

NOVO DR
develops and manufactures cutting edge Portable Digital Radiography X-ray Inspection Systems.

5901 views
Technical Discussions
Navish M
Navish M
07:54 Jan-12-2009
Lifting Capacity of Yokes

Hello All,

What is the reason behind the lifting capacity of yokes 40lbs on permanent magnet and 10lbs on AC yokes?

Thanks

    
 
 
Nigel Armstrong
Engineering, - Specialist services
United Kingdom, Joined Oct 2000, 1094

Nigel Armstrong

Engineering, - Specialist services
United Kingdom,
Joined Oct 2000
1094
12:27 Jan-12-2009
Re: Lifting Capacity of Yokes
In Reply to Navish M at 07:54 Jan-12-2009 (Opening).

Navish

The requirement of 40lb lift is for DC as well as permanent yokes. DC produces a constant-direction, constant-strength field whereas AC produces a 50 Hz reversing direction and fluctuating-strength field. Have you ever tried lifting MORE than 10lb with an AC yoke, very difficult. Even the 10lb lift needs a well-maintained, flat-footed and deftly handled AC yoke to persistently achieve the lift.

    
 
 
Sibusiso MZILA
Engineering, Pipeline integrity
Transnet SOC Limited, South Africa, Joined May 2004, 12

Sibusiso MZILA

Engineering, Pipeline integrity
Transnet SOC Limited,
South Africa,
Joined May 2004
12
10:06 Jan-13-2009
Re: Lifting Capacity of Yokes
In Reply to Navish M at 07:54 Jan-12-2009 (Opening).

The major reason for this difference is based on the expected or required depth of penetration; AC has a maximum of 2mm penetration for surface testing whilst DC is expected to penetrate up to 8mm for surface and sub-surface testing.

    
 
 
Nilesh
Nilesh
13:48 Jan-13-2009
Re: Lifting Capacity of Yokes
In Reply to Navish M at 07:54 Jan-12-2009 (Opening).

Navish Mujawar,
Lifting capacity of yokes are 40 lbs for DC as well as permanent yoke.
Permanent yoke shall have 40 lbs since we are not using any current with it. So fully charged Permanent yoke lift 40 lbs. Due course of time its lifting capacity will drop down in that case you have to send it for re charging. These are used for normally sub surface discontinuities. But for AC as Mr. Nigel explained in one second AC changing its polarity for fifty times. So there is no chance for creating hard magnetic field. and it can lift 10 lbs. Its again gives us better results for surface discontinuities. AC producing magnetic field with sine wave current.
better mobility for particles and lighter penetration in material.

    
 
 

Product Spotlight

Trade-In Offer

We are offering our existing clients trade-in against Wavemaker® G3 systems, Standard (Blue) inflat
...
able rings and modules for excellent deals on the latest Wavemaker® G4mini system.
>

FlexoFORM™

The FlexoFORM™ solution integrates flexible phased array probe technology in a scanner to solv
...
e the challenges that come with inspecting pipe elbows. When combined with a water column, this solution can be used to collect easy-to-interpret data on elbows with diameters ranging from 4.5 in. OD up to flat and offers many benefits.
>

Exertus Dual 120

The Exertus Dual 120 Projector has the ability to accept Iridium 192 sources or Selenium 75 source
...
s. This projector incorporates design and safety features that make it flexible, compact and lightweight. The Projector is lighter than most of its competitors. It incorporates an improved source channel, based on a new helicoidal design, which makes maintenance easier. The helicoidal design also allows smoother movement of the source assembly inside the device, making it easier for the operator and improving safety. The Projector also has a unique safety feature not found in competitive products. The source assembly locking mechanism is triggered by the source holder capsule at the front of the source assembly, thereby always assuring the operator that the source has returned to the safe position. The Exertus Dual 120 is ISO3999:2004 compliant.
>

IntraPhase Athena Phased Array System

The Athena Phased Array system, manufactured by WesDyne NDE Products & Technology, consists of a pha
...
sed array acquisition system and PC running IntraSpect software. A PC is used to perform acquisition, analysis and storage of the data. System hardware is capable of operating up to four data sets with any combination of phased array or conventional UT probes. NOW AVAILABLE IN 64-64 CONFIGURATION.
>

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