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 -
2327 views
Technical Discussions
Suresh
Suresh
07:04 Sep-22-2008
RT Back Scattering

Hi,
How does a letter B appears black in RT film, when it is placed at the back of film ?

I find some procedures mentioning,

"If a dark image "B" appears on a lighter background then this is not a cause for rejection"

thanks for replies,


Suresh


    
 
 Reply 
 
ezio
Other, Retired ex Laboratory Technical Manager
OMECO Research Centre, Italy, Joined Sep 2008, 273

ezio

Other, Retired ex Laboratory Technical Manager
OMECO Research Centre,
Italy,
Joined Sep 2008
273
07:44 Sep-22-2008
Re: RT Back Scattering
----------- Start Original Message -----------
: Hi,
: How does a letter B appears black in RT film, when it is placed at the back of film ?
: I find some procedures mentioning,
: "If a dark image "B" appears on a lighter background then this is not a cause for rejection"
: thanks for replies,
:
: Suresh
------------ End Original Message ------------

It is correct: if B appears darker, back scatterig radiation is irrelevant.


    
 
 Reply 
 
DJ Kallhof
DJ Kallhof
09:16 Sep-22-2008
Re: RT Back Scattering
The reason it shows up on the film dark is from scatter between the "B" itself and the film.
----------- Start Original Message -----------
: Hi,
: How does a letter B appears black in RT film, when it is placed at the back of film ?
: I find some procedures mentioning,
: "If a dark image "B" appears on a lighter background then this is not a cause for rejection"
: thanks for replies,
:
: Suresh
------------ End Original Message ------------




    
 
 Reply 
 
Nigel Armstrong
Engineering, - Specialist services
United Kingdom, Joined Oct 2000, 1096

Nigel Armstrong

Engineering, - Specialist services
United Kingdom,
Joined Oct 2000
1096
00:57 Sep-23-2008
Re: RT Back Scattering - slight edit
Hi Suresh

A light image "B" on the film against a darker background means less radiation is reaching the film immediately under the "B" than is reaching the surrounding area. The lead letter is SHIELDING the film from scattered radiation from materials behind the film which lie in the radiation path. UNACCEPTABLE.

If the density of the surrounding film is less than that of the image of the "B", i.e. the "B" is a dark image against a lighter film background, then the scatter effect is weaker from the background than backscatter and/or emission from the lead "B". ACCEPTABLE.


Thoughtful set-up and use of lead sheet will minimise backscatter.

Good shooting.

Nigel

----------- Start Original Message -----------
: : Hi,
: : How does a letter B appears black in RT film, when it is placed at the back of film ?
: : I find some procedures mentioning,
: : "If a dark image "B" appears on a lighter background then this is not a cause for rejection"
: : thanks for replies,
::
: : Suresh
: It is correct: if B appears darker, back scatterig radiation is irrelevant.
------------ End Original Message ------------




    
 
 Reply 
 

Product Spotlight

Magnetic X-Ray Pipeline Crawler

Zhong Yi brand pipeline crawler is magnetic/micro-video controlled crawler with DC X ray unit inst
...
alled for checking welding of pipeline. Move steadily inside the pipeline 6''-60''diameter with speed of up to 18m/min, Max. moving diatance 5 kilometers and provide the efficient inspection of the pipeline.
>

SITEX CPSERIES

Teledyne ICM’s CPSERIES has been designed with a view to revolutionizing the handling and perfor
...
mances of portable X-Ray sets. Despite having managed to halve the weight of similar portable X-Ray generators available on the market (while continuing to provide the same power output), the SITEX CPSERIES generators feature a shutter, a laser pointer, a beryllium window, an aluminum filter and two integrated diaphragms (customized sizes are available upon request). Without compromising the robustness and reliability for which ICM products are renowned, the small size and light weight of the SITEX CPSERIES will radically change the way that you perform your RT inspections. And you will see a positive impact in terms of both quality and return on investment (ROI).
>

Cygnus 6+ PRO Multi-Mode Ultrasonic Thickness Gauge

The Cygnus 6+ PRO thickness gauge is the most advance gauge within the Cygnus range with key featu
...
res including: comprehensive data logging; A-scan and B-scan display; manual gain control; Bluetooth connectivity; and much more. With its unique dual display and three measuring modes (Multiple-Echo, Echo-Echo and Single-Echo), this surface thickness gauge offers maximum versatility for inspections.
>

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