PRINCIPAL TECHNICAL NOTE

The RD model screens are made of a fixed part and a movable one. The fixed part, having an inclination of 15 degrees apeak, includes the bar section, the skid of the bar extension, the side-runners, the upper and lower joining-girders. The movable part is composed of a steel trolley on which are assembled the rotating comb and the respective trolley shifting and rotating comb hydraulic systems.

 

 

The rotation of the comb comes to an end by some hydraulic cylinders while the shifting of the comb-holder trolley is achieved by a two-shafted hydraulic motor that operates two tight epicycloidal reducers on which two crowns fit together. These ones couple with some racks fixed upon the side-runners. In the course of bar-cleaning the hydraulic system, which is assembled on the trolley, gives to the comb a rotation towards the canal-bed of the riddling bars. At the bottom the bars are shaped in such a way as to help the comb raking-up working; in fact they end in a bending radius which measures 400 millimetres. The rotation causes a progressive coming of the comb-teeth into the bars. In this way the comb-teeth carry the bottom material towards the bars before; afterwards they begin by cleaning the vertical part.

While the trolley comes down, the rotating comb is open (it’s parallel to the bars). At the discharge outlet a scraping blade cleans the comb draining away the material on to the back of the fixed skid. The rotating comb wheels around over some flanged pins on which are assembled some special bushes in self-oiled material. The comb-holder trolley is provided with six wheels in bronze material or in a special material (Derlyn). These wheels make it possible to shift the trolley inside of the two side-runners. The wheels fit together upon some flanged pins which are fixed to the trolley flanks. It is possible to pull completely out the comb-holder trolley from the machine in case of eventual overhauling or important repairs. The trolley runners of the RD model are the biggest compared to the CR and CMR model runners and so is the whole structure. The bar section includes some flat structural shapes which standard thickness is: 40x8, 40x10, 60x10 centimetres. Other sections are used by request. At the bottom of the machine the bars are fixed to the plate lying on the ground, whereas at the top they are fixed to the structure of the bar extension. As regards the construction there are no limits about the height of the bars. The least cleft among the bars measures 12 millimetres

The main characteristics of this machine are strength and best assurance, which is certainly indicative of excellent quality and good working. The machine is used for canals from 1,5 mt. to 3,5 mt. and it may reach over 10-15 mt. In this case the screen that we supply, is divided into two parts or into several parts. They must be joined on spot in such a way as to help the transport and the assembly. The standard machine is provided with a pipe-winder drum and a device of hydraulic lock marked “CF”. This kind of device stops the trolley at the top of the screen when the trolley remains stationary. In addition to a pressure-gauge that you can find at the end of the climb, we assemble (as an optional fitting) an end of stroke running in an emergency.

It is very important to point out that, as it is not used the end of stroke, inside of the machine there isn’t any kind of electrical equipment or electromechanical equipment, which makes it possible a safer installation especially in humid environments running a flooding danger or in explosion-risk areas. All the hydraulic operations inside of the machine are regulated by a hydraulic power plant staying apart from the machine and laying down everywhere. Inside of the power plant (as a standard fitting) we assemble an electric panel which is used for the control and the inspection of the screen. The electrical cables of the hydraulic power plant are protected by some oil-less sheathings.

Inside of the electric panel we assemble a Digital programmer with which it is possible to set the length of the stroke when the trolley comes down; in this way the bar-cleaning can start at the height that you prefer. When the electric panel is not supplied, the power plant is provided with a branch-circuit box and an inside terminal board. The machine works making breaks which can be anyway tuned up. During the break the trolley always stops at the top of the machine. In case of stress or difficulties during the working the trolley automatically reverses. The machine is furnished with CE mark and it can be supplied with different optional fittings.