METHOD AND APPARATUS FOR IMPREGNATING THE SURFACE REGION OF AN ARTICLE
First Claim
1. A method of impregnating a surface region of an article made from a porous material, the method comprising the steps of:
- i) immersing the article in a liquid impregnating material;
ii) withdrawing the article from the liquid impregnating material into a transfer region;
iii) transferring the article from the transfer region into a removal region separated from the transfer region by a separation gas flow; and
iv) displacing excess impregnating material (12) from the surface of the article by exposing the article to the separation flow and a flow of gas in the removal region,wherein the separation gas flow is directed generally horizontally across an opening of the removal region; and
,the flow of gas to remove excess impregnating material is directed obliquely with respect the separation gas flow.
1 Assignment
0 Petitions
Accused Products
Abstract
An article 6 made from a porous material, such as a ceramic material, is dipped into a liquid impregnating material 12, such as molten urea in a bath 14. After withdrawal from the bath 14, excess impregnating material 12 is removed from the article 6 by means of an air knife 22. The air knife 22 is directed obliquely into an enclosure 18, which is maintained at a temperature above the melting point of urea. The article is passed into the enclosure 18 through the flow from a further air knife 20 which creates a separation airflow separating the interior of the enclosure 18 from the ambient surroundings. The article is carried by a fixture 6 to be conveyed along the processing line on a conveyor 2.
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Citations
20 Claims
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1. A method of impregnating a surface region of an article made from a porous material, the method comprising the steps of:
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i) immersing the article in a liquid impregnating material; ii) withdrawing the article from the liquid impregnating material into a transfer region; iii) transferring the article from the transfer region into a removal region separated from the transfer region by a separation gas flow; and iv) displacing excess impregnating material (12) from the surface of the article by exposing the article to the separation flow and a flow of gas in the removal region, wherein the separation gas flow is directed generally horizontally across an opening of the removal region; and
,the flow of gas to remove excess impregnating material is directed obliquely with respect the separation gas flow. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 15, 16, 17, 18, 19, 20)
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14. A method of impregnating a surface region of an article made from a porous ceramic material with urea, the method comprising the steps of:
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i) immersing the article in molten urea; ii) withdrawing the article from the molten urea; and iii) displacing excess urea from the surface of the article by exposing the article to a separation gas flow and a flow of gas within a removal region, at a temperature higher than the melting point of urea, wherein the separation gas flow is directed generally horizontally across an opening of a removal region; and
,the flow of gas to remove excess urea is directed obliquely with respect the separation gas flow.
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Specification