# US 4,396,401 A · Poking system for gasifiers > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 4,396,401 A - Document ID: US4396401A - Status: Granted - Kind: A - Application number: 06/288,126 - Filed: 1981-07-29 - Granted: 1983-08-02 - Earliest claimed: 1980-08-02 - Assignees: Wellman Mechanical Engineering Limited - Inventors: Roderick M. Davis - Web page: https://patentgrep.com/patent/US4396401A ## CPC - C10J 3/32: Devices for distributing fuel evenly over the bed or for stirring up the fuel bed - C10J 3/20: Apparatus; Plants - C10J 3/36: Fixed grates - C10J 3/723: {Controlling or regulating the gasification process} - C10J 2300/093: Coal - C10J 2300/0956: Air or oxygen enriched air - C10J 2300/0959: Oxygen - C10J: PRODUCTION OF PRODUCER GAS, WATER-GAS, SYNTHESIS GAS FROM SOLID CARBONACEOUS MATERIAL, OR MIXTURES CONTAINING THESE GASES (synthesis gas from liquid or gaseous hydrocarbons C01B; underground gasification of minerals E21B43/295); CARBURETTING AIR OR OTHER GASES ## Abstract A poking system for use in checking the condition of and agitating the contents of a coal gasifier utilizes a carriage (22) for transporting a poker (50) around the gasifier from one poke hole (12) to another. The carriage (22) mounts a poker assembly (24) comprising a tiltable arm (30) controlled by hydraulic ram (36) and the poker is incrementally inserted into and with withdrawn from each pokehole (12) by means of a reciprocable slide (38) provide with poker engaging clamps (60) which are operated during the advance or return stroke of the slide (38) depending on whether the poker is to be inserted or withdrawn. A pyrometer (72) is provided on the arm (30) for detecting, during withdrawal, the location of that portion of the poker (50) which has been resident within the oxidation zone of the gasifier. ## Claims ### Claim 1 Apparatus for sensing temperature within the interior of a gasifier, said apparatus comprising a rod, means for advancing and retracting the rod into and out of the gasifier, means for sensing the position of the rod with respect to a datum position at least during withdrawal of the rod and a temperature sensor disposed externally of the interior of the gasifier adjacent the path of travel of the rod for sensing the temperature of the rod along its length as the rod is withdrawn from the gasifier whereby the positions and temperatures sensed by said position-sensing means and said temperature sensor respectively can be combined to provide an indirect indication of the location of one or more temperature-transition zones within that region of the gasifier from which the rod is withdrawn. ### Claim 2 (depends on 1) Apparatus as claimed in claim 1 in which the temperature sensor is constituted by a pyroelectric device providing an electrical output representing the radiation sensed. ### Claim 3 (depends on 2) Apparatus as claimed in claim 2 in which the pyroelectric device is associated with a threshold detector to determine whether the electrical output of the device is above or below a predetermined value corresponding to the radiation level emitted by that portion of the rod which, prior to withdrawal, has been exposed to and has approached thermal equilibrium with the oxidation zone of the gasifier. ### Claim 4 (depends on 1) Apparatus as claimed in claim 1 including means for adjusting the angle of entry and withdrawal of the rod into and out of the gasifier. ### Claim 5 (depends on 1) Apparatus as claimed in claim 1 in which the rod, said advancing and retracting means and the temperature sensor are all mounted on a mobile carriage which, in turn, is mounted on a track extending about the gasifier. ### Claim 6 (depends on 5) Apparatus as claimed in claim 5 in which said rod, and said advancing and retracting means are all mounted on the carriage through the agency of a slide structure provided with means for adjusting the slide structure relative to the carriage inwardly and outwardly with respect to the gasifier. ### Claim 7 (depends on 1) Apparatus as claimed in claim 1 in which said rod-advancing and retracting means comprises a reciprocating device and means for selectively coupling the rod to the reciprocating device during strokes of the latter in one direction or during strokes of the latter in the opposition direction whereby the rod is either advanced incrementally into the gasifier or retracted incrementally from the gasifier. ### Claim 8 (depends on 7) Apparatus as claimed in claim 7 in which said coupling means is further operable selectively to couple the rod to the reciprocating device during both strokes of the latter whereby the rod can be reciprocated back and forth in order to agitate the contents of the gasifier. ### Claim 9 (depends on 8) Apparatus as claimed in claim 8 in which said reciprocating device comprises a fluid-powered piston and cylinder assembly and further includes a pressure sensor associated with said cylinder to sense the fluid pressure therein and thereby provide a measure of the force applied to the rod by the reciprocating device, said coupling means being operable to couple the rod to the reciprocating device during both strokes of the latter when said pressure sensor indicates that the applied force exceeds a predetermined value.