PAMIR-250 pulse X-ray machine

A pulsed x-ray unit with a voltage on a x-ray tube of 250 kilovolts, the PAMIR-250 is part of the PAMIR series of advanced pulse-based flaw detectors. The instruments of this line (see also PAMIR-200, PAMIR-300) were developed on the basis of the popular pulsed x-ray machines ARINA. PAMIR 250 is identical in radiographic characteristics to X-ray equipment ARINA-7, but surpasses it in some performance characteristics. In PAMIR-250, the time of continuous operation of the X-ray tube is increased, it is more “durable” with intensive operation in operating modes close to the limit.

PAMIR 250 - solvable problems

The purpose of the PAMIR 250 X-ray machine is to conduct X-ray inspection of welds of metal structures with a wall thickness of up to 80 millimeters (the value for steel, with high-sensitivity x-ray film, using fluorescent reinforcing screens). The PAMIR-250 X-ray unit acts as a portable source of ionizing penetrating radiation. Most often used when performing work on non-destructive testing of welded joints of pipelines in non-stationary conditions.
Power supply of PAMIR-250 can be carried out both from an autonomous battery source, for example, SPRUT IPA-24.18, and from an industrial AC mains 220 V.

PAMIR 250 - the design of the elements and the operation of the X-ray unit

The main elements of the device are an X-ray emitter and a portable control panel, interconnected by a 30-meter cable. The removal of the control panel from the radiating unit to such a distance (in the direction opposite to the exit of the working beam of radiation) ensures the protection of the operator during the exposure.
The emitter unit consists of a high-voltage module filled with oil and a primary circuit that provides pulses to the input of the high-voltage unit.

The high-voltage module includes a pulse transformer, a spark gap discharger, an X-ray pulsed X-ray tube with a cold cathode. The primary circuit consists of storage capacitors and a gas switch. These circuits of the radiating unit PAMIR-250 form short high-voltage nanosecond pulses at the electrodes of the vacuum tube. With such a short but powerful effect, a process of explosive electron emission occurs in the vacuum gap of the tube, accompanied by a flash of x-rays.
In the PAMIR-250 control panel there are: a source of primary voltage, an exposure timer, a control and protection circuit. The primary voltage source is a single-cycle high-frequency transistor oscillator with self-excitation, the load of which is a high-voltage step-up transformer.

The control and protection circuits ensure stable operation of the generator and circuit protection in the absence of a load (the high-voltage cable connector is not inserted) in the high-voltage circuit and protection from overheating.
To eliminate the possibility of unauthorized use of the device is equipped with a security lock.
The following controls and displays are located on the front panel of the control panel:

Toggle switch on the network.
Security key (also known as an X-ray activation key).
Exposure timer
Button start exposure.
The timer has several time ranges. Their switching is carried out using a microswitch located in the lower left corner of the timer faceplate. From the factory, the device comes out with a timer setting for 5 minutes.
To improve the image quality by reducing the effect of scattered photons on the film, as well as to provide additional safety measures for operators when working with ionizing radiation sources having a wide angle of the working radiation beam solution, the XRS-AP collimator is recommended for frontal translucency.