The half-value layer of an X-ray machine is the thickness of the material required to weaken the intensity of electromagnetic rays to half of the initial value, the half-value layer is a representation of the shielding thickness, the shielding thickness of the commonly used representation of the lead equivalent, the half-value layer and 1/10 value layer.
The half-value layer reflects the ability of the ray to penetrate, for the half-value layer of the X-ray machine, need to be measured or calculated to ensure that the machine works.
The half-value layer is the thickness of the layer of material required to attenuate the number of incident X- or gamma-ray photons by half (50%), and is expressed as HVT. By analogy, a 1/10-value layer is the thickness of the material layer required to attenuate the number of incident X or γ-ray photons to 1/10 (10%), denoted by TVT.
HVT and TVT conversion relationship: 1HVT = 0.301TVT; 1TVT = 3.320HVT. In the shielding design is also often used to shielding materials on the ray half-value layer thickness and 1/10 value layer thickness to evaluate the shielding performance of the material on the ray and used to calculate the thickness of the shielding required. For X-ray machine half-value layer, need to be measured or calculated to ensure that the work of the machine.
Expanded Information:
An X-ray machine is a device capable of generating X-rays, which can be categorized into an industrial X-ray machine and a medical X-ray machine depending on its use.
1, industrial X-ray machine:
The use of high-voltage transformer added to the two metal electrodes of high voltage to produce rays. Industrial X-ray machine for aerospace, petroleum construction, natural gas pipelines, boilers, pressure vessels and other non-destructive flaw detection indispensable equipment. Industrial ray machine is divided into circumferential, circumferential 360 degrees to emit rays. Directional is 60 degrees to launch rays. Another sub voltage high and low.
From 10kV to 450kV, the higher the kV voltage, the greater the intensity of the ray. Hard x-rays can be generated with high voltage electrical methods, such as 100kV or 300kV voltage added to the x-ray tube, the resulting rays can penetrate 5 - 50mm steel plate. And the use of electron gas pedal methods can produce rays that penetrate more than 100mm of steel plate.
2, medical X-ray machine:
Medical X-ray machine is also called X-ray diagnostic equipment or medical X-ray fluoroscope. Medical X-ray diagnostic equipment is the earliest application, clinical popularity of the most widely used means of medical imaging. In other medical imaging in the section before the emergence of more than half a century, it has been the only clinical image visualization method.
These X-ray machines are suitable for medical use and are widely used in medical institutions and places, providing rapid medical diagnosis for relevant units. Most of its high-voltage generators are digital high-frequency, featuring rich layers of photographic imaging and a simple and friendly operating interface.
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