| All Patents in class 451/347 |
Patents 1 -
9
of 9
      |
| Picture | Number | Date | Patentee | Title |
| | 1,987,837 | Jan. 15, 1935 | A.W. Mall | Portable grinding machine |
| | 2,081,360 | May 25, 1937 | A.W. Mall | Rail slotter |
| | 2,106,034 | Jan. 18, 1938 | A.W. Mall | Rail grinder |
| | 2,116,491 | May 03, 1938 | A.W. Mall | Angle grinding spindle |
| | 2,148,766 | Feb. 28, 1939 | A.W. Mall | Track grinding machine |
| | 2,214,141 | Sep. 10, 1940 | A.W. Mall | Rail slotter |
| | 2,223,732 | Dec. 03, 1940 | A.W. Mall | All purpose grinding apparatus |
 | 3,509,667 | May 05, 1970 | K.L. Lindmark | Method of grinding welded rail |
 | 3,566,546 | Mar. 02, 1971 | K.L. Lindmark | Apparatus for grinding welded rail |
