Inventor

HEROLD JOHN R

US2 patents

⚠️ This page may combine multiple inventors who share the name “HEROLD JOHN R”. Patents are grouped by organization below to help distinguish them — per-person disambiguation is on the roadmap.

FMC CORP

1 patent

US5782297AJul 21, 1998

Retrieval tool for back pressure valve and tree test plug

FMC CORP34 citations90

(unassigned)

1 patent

US5474124ADec 12, 1995

Wellhead retrieval tool assembly

15 citations69