The present invention relates to a method and apparatus for producing heating elements in the form of tubes with a resistive heater therein, surrounded by refractory powder. A filling pipe is inserted into said tube, and powder is allowed to flow down said pipe. The pipe is moved upwardly, to allow powder to flow out, and then moved downwardly to rest on the powder. In a preferred form, the pipe is forced downwardly to further compact the powder, preferably by means of an impact with a hammer. Means may be provided to selectively grip the pipe to move it upwards, and the gripping means and the hammer can have a common drive mechanism. A valve may be provided to allow flow of powder into the pipe to be shut off when said tube is filled with powder.

 
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