| 摘要 |
The invention relates to spray valves (1) particularly for the direction of coolant against rolling rolls. During cold rolling there is an inevitable heating effect caused by the friction between a roll and the material being rolled that can distort the roll surface to provide a convex or a concave roll surface. Unless corrected the result would be the rolling of non-flat plate strip or foil. There are known valves and techniques for the selective spraying of a roll surface to assist in the prevention in the distortion of its surface. The invention has for its objective to improve such valves and techniques, which objective is met by a method of controlling the provision of coolant along the length of a roll by providing independent control over a number of spray valves strategically located along the length of the roll, each spray valve being separately controlled in accordance with the sensing of a deviation from flatness of the roll or a product rolled by the roll, each spray valve being so structured and controlled to enable it to be selectively switched on and off and when switched on be so controlled as to allow a variation of coolant issued by the spray valve. A valve to serve this purpose comprises a chamber, an outlet (3) from the chamber, a piston (5) slidably located in the chamber (4), at least one fluid inlet to the chamber, said piston cooperating with said at least one fluid inlet to provide a variable degree of opening and/or cooling of the fluid inlet and whereby to provide a variable degree of coolant issuing from the outlet from the chamber. |
