Inventor
HELFERICH RICHARD L
US11 patents
⚠️ This page may combine multiple inventors who share the name “HELFERICH RICHARD L”. Patents are grouped by organization below to help distinguish them — per-person disambiguation is on the roadmap.
DURIRON CO
8 patentsUS4871495AOct 3, 1989
Process for producing porous ceramic filter for filtering of particulates from diesel exhaust gases
DURIRON CO68 citations95
US4432798AFeb 21, 1984
Aluminosilicate hydrogel bonded aggregate articles
DURIRON CO101 citations95
US4963515AOct 16, 1990
Lightweight hydrogel-bound aggregate shapes and process for producing same
DURIRON CO23 citations92
US4814300AMar 21, 1989
Porous ceramic shapes, compositions for the preparation thereof, and method for producing same
DURIRON CO42 citations92
US4357165ANov 2, 1982
Aluminosilicate hydrogel bonded granular compositions and method of preparing same
DURIRON CO40 citations92
US4846906AJul 11, 1989
Methods for the manufacture of porous ceramic shapes containing membraneous surfaces
DURIRON CO33 citations91
US4812424AMar 14, 1989
Kiln furniture for the firing of ceramic articles
DURIRON CO20 citations81
US4878947ANov 7, 1989
Method for manufacture of porous refractory articles
DURIRON CO14 citations73