GB1318802A - Apparatus for producing thermoplastic foam - Google Patents

Abstract

1318802 Mixing apparatus MIDLAND INSULATORS (NOTTINGHAM) Ltd and E H O'HARA 10 May 1971 [13 May 1970] 50468/ 72 Divided out of 1318801 Heading B1C [Also in Division C3] Apparatus for producing foamed urea formaldehyde resins, from the resin and a catalyst, comprises a gun for foaming either the catalyst or the resin, the gun having an outlet for spraying the foam, pressure vessels for the resin and the catalyst respectively connected to the gun, a reserve container connected through a control valve to each vessel. Optionally these may be provided an audible alarm system which indicates when the content of either vessel reaches a given minimum level. The valves may be operated automatically or manually. The reserve containers may be open or pressurised vessels. In the drawing, pressure vessels 1, 2 are connected via 3, 4 to foaming gun 5 which is also fed by compressed air from line 6. Vessel 1 is filled with urea formaldehyde resin while 2 is filled with a catalyst comprising phosphoric acid. 7 and 8 are reserve vessels connected to 1, 2 via valves 9, 10. Audible alarm 11 is connected to level sensors in 1, 2 and operates valves 9, 10. Gun 5 comprises chamber 12 filled with glass balls 13 and nozzle 14, and is fed with air from 6, resin from 1 and catalyst from 2 so as to produce foam in spray form from 14. When the level of either vessel 1 or 2 reaches a given minimum, alarm 11 is operated thereby opening valves 9 and 10 to replenish vessel 1 or 2 from 7 or 8. Connections 3, 4 to gun 5 may be interchanged so as to foam the resin instead of the catalyst.