Abstract: A kiln includes a hollow elongated housing which has an inlet and an outlet spaced from each other defining between them the interior of the housing designed to receive through the inlet the items to be treated. The housing includes a number of sections operative for treating the items as they gradually pass through the sections towards the outlet with different respective treating regimes. The sections downstream of the housing are interconnected with the section upstream of the housing so as to recover the heated gas from the downstream sections and supply the same into the upstream section in predetermined quantities and at a predetermined temperature.

Abstract: An insulation structure includes a hollow housing having first and second side walls spaced from each other, defining therebetween the interior of the housing. The walls are provided with a plurality of throughgoing holes. A plurality of rotatable rollers is provided in the housing extending from the first to the second walls. Each of the rollers has a portion which is narrower than that of the respective hole and which extends therethrough to the exterior of the housing. The structure is further provided with insulation to prevent heat leakage from the interior of the housing through the circumferential passage defined between the outer surface of each roller and the inner surface of the respective hole.

Abstract: A kiln includes a hollow housing which has an upper and lower wall, an inlet and outlet. The lower wall of the housing is provided with a first set of baffles spaced from one another along the length of the housing and extending towards the upper wall of the housing. The upper wall of the housing is provided with a second set of baffles spaced from one another along the length of the housing and extending towards the lower wall. The first and second sets of baffles bound betweem them a gap defining a transport path for items to be treated. At least one set of baffles is adjustable so as to vary the width of the gap.

Abstract: A hydraulic system for supplying hydraulic fluid to a hydraulically operated device alternately at pressures of different values, said system comprising a first hydraulic circuit arranged to be supplied with hydraulic fluid at a low pressure by a pump and for supplying the hydraulic device with fluid at said low pressure through a pilot operated valve, a second hydraulic circuit provided with a pressure multiplier piston device which produces hydraulic fluid at a pressure greater than that of the low pressure fluid and having a first chamber connected to the first hydraulic circuit and a second chamber of smaller area than the first chamber connected to the second hydraulic circuit, the second hydraulic circuit being provided with a pressure accumulator for maintaining high pressure in the second hydraulic circuit and said second hydraulic circuit being provided with a second pilot operated valve for supplying the hydraulic device with fluid at said high pressure.