METHOD OF INSPECTING AIR-TIGHTNESS OF SINGLE-BLOCK GAS LASERS DISCONNECTED FROM EXHAUST CART BY EMISSION SPECTRAL ANALYSIS

摘要

FIELD: physics.;SUBSTANCE: method of inspecting air-tightness of single-block gas lasers disconnected from an exhaust cart includes using a test gas to evaluate air-tightness, selecting analytical pairs of spectral lines of the test and working gases to estimate concentration of the test gas, plotting a calibration curve of relative intensity of the selected analytical pair versus concentration of test gas, recording the radiation spectrum of the glow discharge of the inspected laser, determining concentration of the test gas from the calibration curve, creating a closed volume around the inspected laser casing, filling said closed volume with the test gas, accumulating the test gas in the inspected laser, recording lines of the test gas in the radiation spectrum of glow discharge after storage in the medium of the test gas, determining concentration of test gas from the calibration curve and evaluating air-tightness of the laser from the difference in measured concentration of test gas before and after the control storage time. The test gas used is a gas which is not the working gas for said laser or a typical impurity gas and having in the selected spectral region lines which do not overlap with lines of the main gases or molecular bands of typical impurity gases, having high intensity at low concentration of the test gas. The time during which the inspected article is held in the medium of said gas is determined using the formula: Δt≥P_min∗V/Q, where Δt is the time for holding in the medium of the test gas, s; P_min is the minimum pressure of the test gas which can be detected, Pa; V is the volume of the gas mixture of the single-block gas laser, m³; Q is the minimum leakage flow rate to be detected, Pa·m³/s.;EFFECT: faster inspection.;2 dwg