Methods for performing inspections and detecting chemical leaks using an infrared camera system

A method of visually detecting a gas leak of any one or more chemicals of a group of predetermined chemicals, the gas leak emanating from a component of a group of components in different locations, the method comprising:

• aiming a passive infrared camera system towards the component, wherein the passive infrared camera system comprises:
• a lens,
• a refrigerated portion defined by the interior of a Dewar flask, the refrigerated portion comprising therein:
• an infrared sensor device;
• and
• a single filter configuration comprising at least one fixed optical bandpass filter, each filter fixed along an optical path between the lens and the infrared sensor device, the single filter configuration comprising an aggregate pass band with a full width at half maximum transmittance being less than about 600 mn, wherein at least part of the aggregate pass band for the single filter configuration is within an absorption band for each of the predetermined chemicals and wherein the aggregate pass band for the at least one optical bandpass filter is at least about 200 mn;
• and
• a refrigeration system adapted to cool the refrigerated portion, the refrigeration system comprising a closed-cycle Stirling cryocooler;
• receiving an infrared image with the infrared sensor device of the gas leak under normal operating and ambient conditions for the component, after the infrared image passes through the lens and the at least one optical bandpass filter, and after the infrared image is filtered by the at least one optical bandpass filter;
• electronically processing the filtered infrared image received by the infrared sensor device to provide a visible image of the gas leak under variable ambient conditions of the area around the leak;
• and
• visually detecting the leak based on the visible image under the variable ambient conditions.

A method of visually detecting a gas leak of any one or more chemicals of a group of predetermined chemicals, the gas leak emanating from a component of a group of components in different locations, the method comprising:

• aiming a passive infrared camera system towards the component, wherein the passive infrared camera system comprises:
• a lens,
• a refrigerated portion defined by the interior of a Dewar flask, the refrigerated portion comprising therein:
• an infrared sensor device;
• and
• a single filter configuration comprising at least one fixed optical bandpass filter, each filter fixed along an optical path between the lens and the infrared sensor device, wherein the aggregate pass band for the single filter configuration is at least from about 3100 nm to about 3600 nm and at least about 200 nn and wherein at least part of the aggregate pass band for single filter configuration is within the absorption band for each of the predetermined chemicals;
• and
• a refrigeration system adapted to cool the refrigerated portion, the refrigeration system comprising a closed-cycle Stirling ciyocooler;
• receiving an infrared image with the infrared sensor device of the gas leak under normal operating and ambient conditions for the component, after the infrared image passes through the lens and the at least one optical bandpass filter, and after the infrared image is filtered by the at least one optical bandpass filter;
• electronically processing the filtered infrared image received by the infrared sensor device to provide a visible image of the gas leak under variable ambient conditions of the area around the leak;
• and
• visually detecting the leak based on the visible image under the variable ambient conditions.

A method of visually detecting a gas leak of any one or more chemicals of a group of predetermined chemicals, the gas leak emanating from a component of a group of components in different locations, the method comprising:

• aiming a passive infrared camera system towards the component, wherein the passive infrared camera system comprises:
• a lens,
• a refrigerated portion defined by the interior of a Dewar flask, the refrigerated portion comprising therein:
• an infrared sensor device;
• and
• a single filter configuration comprising at least one fixed optical bandpass filter, each filter fixed along an optical path between the lens and the infrared sensor device, wherein the aggregate pass band for the single filter configuration is at least from about 3200 nm to about 3500 nm, is at least 200 nm, and has a center wavelength located between about 3320 nm and about 3440 nm, and wherein at least part of the aggregate pass band for the single filter configuration is within the absorption band for each of the predetermined chemicals;
• and
• a refrigeration system adapted to cool the refrigerated portion, the refrigeration system comprising a closed-cycle Stirling cryocooler;
• receiving an infrared image with the infrared sensor device of the gas leak under normal operating and ambient conditions for the component, after the infrared image passes through the lens and is filtered by the single filter configuration;
• electronically processing the filtered infrared image received by the infrared sensor device to provide a visible image of the gas leak under variable ambient conditions of the area around the leak;
• and
• visually detecting the leak based on the visible image under the variable ambient conditions.