| Number | Date | Country | Kind |
|---|---|---|---|
| 2451/90 | Jul 1990 | IEX | |
| 2454/90 | Jul 1990 | IEX | |
| 704/91 | Mar 1991 | IEX | |
| 1362/91 | Apr 1991 | IEX |
| Number | Name | Date | Kind |
|---|---|---|---|
| 2015959 | Needham | Oct 1935 | |
| 2903302 | Ross | Sep 1959 | |
| 3380780 | Allen et al. | Apr 1968 | |
| 3537187 | Cvacho et al. | Nov 1970 | |
| 3580416 | Hoenisch | May 1971 | |
| 3791046 | Bruggink, Sr. | Feb 1974 | |
| 3877241 | Wade | Apr 1975 | |
| 3903377 | Utter | Jan 1976 | |
| 4055280 | Kohl et al. | Oct 1977 | |
| 4104889 | Hoenisch | Aug 1978 | |
| 4158426 | Fronbieter | Jun 1979 | |
| 4775267 | Yamamoto | Oct 1988 |
| Number | Date | Country |
|---|---|---|
| 0296803 | Dec 1988 | EPX |
| 379544 | Sep 1932 | GBX |
| 2116284 | Sep 1983 | GBX |
| Entry |
|---|
| Patent Abstracts of Japan, vol. 9, No. 80 (M-370) [1803], Apr. 10, 1985; & JP-A-59 209 991 (Touhou Kikai Kogyo K.K.) Nov. 28, 1984. |
| Oil and Petrochemical Equipment News, vol. 12, Nov. 1966, pp. 44, 45, London, GB; J. R. H. Brown: "Pipeline spheres and launching receiving equipment". |