Apparatus for quenching butt-welded portion of rail

An apparatus for quenching a butt-welded portion of a rail, comprising:

• an inverse U-shaped cooling box (2) for covering from above and throughout a butt-welded portion of a rail (1), and for quenching said butt-welded portion by ejection of cooling air, said cooling box (2) including two partition plates (9, 10) for dividing said cooling box into a head cooling chamber (3), a web left cooling chamber (7) and a web right cooling chamber (8), which chambers are independent of each other, each of said head cooling chamber, said web left cooling chamber and said web right cooling chamber having a plurality of cooling air nozzles (13) arranged to be directed toward said butt-welded portion;
• a cooling air supply mechanism for supplying cooling air to said cooling box (2), said cooling air supply mechanism comprising a cooling air source (20), a solenoid valve (22) for selectively opening and closing the flow of cooling air, a cooling air supply pipe arranged with said solenoid valve for introducing cooling air from said cooling air source (20) into each of said head cooling chamber (3), said web left cooling chamber (7) and said web right cooling chamber (8), a head cooling air regulating valve (16) for regulating a flow rate of cooling air to be supplied to said head cooling chamber (3), a web cooling air regulating valve (17) for regulating a flow rate of cooling air to be supplied to said web left cooling chamber (7) and said web right cooling chamber (8), and valve opening controlling means for controlling an opening of each of said head cooling air regulating valve (16) and said web cooling air regulating valve (17);
• and
• a cooling box holding mechanism (36) for releasably holding said cooling box (2) at a prescribed position so as to cover said rail (1) throughout said butt-welded portion, said holding mechanism comprising
• a horizontal supporting plate (37) fixed to a side of said cooling box which extends at right angles to the axial line of said rail,
• a pair of clamps (38, 39) located on the lower surface of said supporting plate for gripping the head of said rail to hold releasably said cooling box (2) at a prescribed position so as to cover said rail throughout said butt-welded portion, one clamp (38) of said pair of clamps being slidable at right angles to the axial direction of said rail along the lower surface of said supporting plate, and the other clamp (39) being fixed to the lower surface of said supporting plate,
• a horizontally arranged rod (40) fixed at one end to said slidable clamp (38) and projecting at right angles to the axial direction of said rail (1), and
• a lever (42) and a link (41) for coupling said lever to the other end of said rod, a top end of said lever being pivotally connected to the lower surface of said supporting plate so that said slidable clamp is guided by said rod and urged by said link to grip the head of said rail in clamping relation with said other clamp when said lever is operated, wherein said cooling box is held at said prescribed position so as to cover throughout said butt-welded portion of said rail.