Tariff classification of compressor spare parts rejected under Heading 90.24; air compressors remain classified separately.

Imported piston rings and rider rings, described as carbon rings and claimed as spares for air compressors in a thermal unit, were held not classifiable under Heading 90.24. Heading 90.24 covers instruments or apparatus for measuring, checking or automatically controlling flow, depth, pressure or temperature, whereas an air compressor is separately covered under Heading 84.11 and does not become classifiable under Heading 90.24 merely because it deals with air or gas pressure. The goods were only compressor parts, and their use in the plant did not alter that classification. The claim for Heading 90.24 or 90.29 was rejected and the revenue classification was upheld.

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Issues: Whether imported piston rings and rider rings, described as carbon rings and stated to be spares for air compressors used in the appellant's thermal unit, were classifiable under Heading 90.24 or under Heading 85.18/27(1).

Analysis: Heading 90.24 applies to instruments and apparatus for measuring, checking or automatically controlling the flow, depth, pressure or other variables of liquids or gases, or for automatically controlling temperature. An air compressor is specifically covered by Heading 84.11, and it could not be treated as an instrument or apparatus falling within Heading 90.24 merely because it deals with air or gas pressure. The imported goods were only parts of air compressors, and the fact that the compressors were used in the appellant's plant did not make the spare parts classifiable with the plant or with Heading 90.24. The claim for classification under Heading 90.24 or 90.29 was therefore not made out.

Conclusion: The goods were not classifiable under Heading 90.24 and the revenue classification was upheld.

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