Question

what is used in the rediography camera​

Answer 1

Most industries are moving from film based radiography to a digital sensor based radiography much the same way that traditional photography has made this move.Since the amount of radiation emerging from the opposite side of the material can be detected and measured, variations in this amount (or intensity) of radiation are used to determine thickness or composition of material.

Torch design

One design is best thought of as being like a torch. The radioactive source is placed inside a shielded box, a hinge allows part of the shielding to be opened exposing the source, allowing photons to exit the radiography camera.



This torch-type camera uses a hinge. The radioactive source is in red, the shielding is blue/green, and the gamma rays are yellow.

Another design for a torch is where the source is placed in a metal wheel, which can turn inside the camera to move between the expose and storage positions.




This torch-type camera uses a wheel design. The radioactive source is in red, and the gamma rays are yellow.

Cable-based design

One group of designs use a radioactive source, which connects to a drive cable contained shielded exposure device. In one design of equipment the source is stored in a block of lead or depleted uranium shielding that has an S-shaped tube-like hole through the block. In the safe position the source is in the center of the block and is attached to a metal wire that extends in both directions, to use the source a guide tube is attached to one side of the device while a drive cable is attached to the other end of the short cable. Using a hand-operated winch the source is then pushed out of the shield and along the source guide tube to the tip of the tube to expose the film, then cranked back into its fully shielded position.



A diagram of the S-shaped hole through a metal block; the source is stored at point A and is driven out on a cable through a hole to point B. It often goes a long way along a guide tube to where it is needed.

Contrast agents

Defects such as delaminations and planar cracks are difficult to detect using radiography, which is why penetrants are often used to enhance the contrast in the detection of such defects. Penetrants used include silver nitrate, zinc iodide, chloroform and diiodomethane. Choice of the penetrant is determined by the ease with which it can penetrate the cracks and also with which it can be removed. Diiodomethane has the advantages of high opacity, ease of penetration, and ease of removal because it evaporates relatively quickly. However, it can cause skin burns.