6 of 6 codes

Code Means Normalised Valid
1 Conductor The outermost, shallowest string. Conductor always
2 Surface Surface casing, set to protect usable-quality water. Surface always
3 Intermediate An intermediate string. Intermediate always
4 Conventional Production Production casing of uniform diameter. Conventional Production always
5 Tapered Production Production casing that changes diameter with depth. Tapered Production always
6 Other Anything else. Other always

Where this mapping came from: OilGasDataProcessing process_completions.translate_casing_type_code (CMPL 'Casing Data' field 15)