A. Celli Paper S.p.a.

Salvatore Sorrentino

Guiseppe Antonini

Mauro Celli

Giuseppe Antonini

A method for producing a Yankee dryer cylinder, or Yankee cylinder, comprises the steps of disposing of a first and of at least a second cylindrical portion of shell. These are made of steel, have the same diameter and are provided with a plurality of grooves at an internal surface. In particular, the portions of shell, at a respective end, are provided of respective flange portions. The method provides to coaxially position the portions of shell up to arrange respective coupling surfaces of the flange portions adjacent one to the other. Then the engagement of the portions of shell is provided by means of a plurality of clamping members, each of which arranged to clamp the adjacent flange portions. Then, it is provided the circumferential welding of the cylindrical portion of the shell that are opposite to the flange portions, and the removal of the clamping members and of the flange portions.

Method for assembling an improved Yankee cylinder

A method for producing a Yankee dryer cylinder, or Yankee cylinder, includes the steps of executing a cylindrical tubular semifinished product made of steel and having a side wall provided with an internal surface and an external surface. A forging step of the cylindrical tubular semifinished product follows for obtaining predetermined thicknesses at the central portion and at the terminal portions of the side wall where the enlarged terminal portions are made. The cylindrical shell is completed executing a plurality of grooves at the internal surface of the cylindrical tubular semifinished product. Then a plurality of longitudinal blind holes are executed at the external surfaces of the enlarged terminal portions of the cylindrical shell. Then, the heads are positioned at each of enlarged terminal portion of the cylindrical shell to which they are fixed by means of studs that pass the blind holes of the shell and respective through holes of which the heads are provided.

Method for producing an improved yankee cylinder

A Yankee dryer cylinder () having a cylindrical shell () having a central portion (), a first and a second end portion () and a longitudinal axis (). At an internal surface (), the cylindrical shell () includes a plurality of circumferential grooves (). The cylinder () includes a first and a second head () fixed, respectively, to the end portions () of the cylindrical shell (). The shell () includes a first and a second group of circumferential end grooves () positioned respectively at the first and the second end portion () and a third group of circumferential grooves positioned at the central portion (). The grooves of the first and of the second group have a width that is greater than the width of the circumferential grooves positioned at the central portion, to uniformly distribute the loads in operating conditions.

Yankee dryer cylinder with improved internal geometry

Yankee dryer cylinder () having a cylindrical shell made of steel (), having a first and a second end opposite each other () and provided with a plurality of circumferential grooves (). The cylinder () includes a first and a second head () made of cast iron and fixed respectively to the first and to the second end () of the cylindrical shell made of steel (). It is, furthermore, provided a hollow shaft () mounted inside the cylindrical shell () and connected to the first and to the second head () at a first and a second end (), respectively. The cylinder is also provided with a first and a second bearing journal () fixed to the hollow shaft () at a respective end ().

Yankee dryer cylinder with controlled thermal expansion

The cylinder () comprises: a shell () and two heads (), defining an inner hollow space (), inside which a heat-transfer fluid flows. Support and rotation journals () are also provided, fixed to said heads; and a thermal insulation system () for the heads (). The thermal insulation system comprises, for each head, a plurality of thermal insulation panels (), each of which comprises a closed space () defined in a shell, inside which there is housed a thermal insulating material ().

Insulation for cylinder heads

The air hood () for Yankee rolls () comprises at least one supply circuit () to supply dry hot air towards outlets (A) to a working area, and at least one suction circuit () to suck wet air from the working area. The hood comprises a thermal insulation insulating at least partially the supply circuit from the suction circuit.

Growing community of inventors

Pinerolo, Italy

Salvatore Sorrentino