Yankee Dryer

Yankee Dryer

YANKEE DRYER

 

PERFORMANCE AND BENEFITS

 

Yankee dryer are used for tissue and machine glazes grader, ABK italia has supplied more than 120 Yankee cylinders in all the world on its machines and on machines and on machines built by other manufacturers on a variety of grades such as creped tissue, hard tissue, MG papers, poster papers, one-side coated board grades, folding boxboard.

 

Special alloys of the Yankee shells and employed for different applications. Chromium plating is also available for special grades.

 

The production program covers:

 

  • Face length up to 3.600mm;
  • Standard diameters of 2.500, 3.200, 3,600 and 4,500mm
  • Total weight up to 50 tons;
  • Operating pressure of 5 or 8.5 bar;
  • Pressure vessel coding available for all countries;
  • Surfaces hardness up to 240 HB

 

SPECIAL FEATURES

 

The construction of a Yankee dryer must be such as to allow operation at high steam pressure, high speed and maximum drying capacity.

This is obtained with a special grooving, or ribbing, of the inner surface.

The condensate will collect in the grooves and the major part of the surface will run dry, eliminating the heat transfer losses due to the condensate layer.

Special stainless-steel spoiler clips inserted in the grooves will induce turbulence in the condensate layer, enhancing further the overall heat transfer. The ribbing of the Yankee requires a special condensate removal device, with multiple header provided with small stainless-steel tube which sip, like a soda straw, the condensate out of each groove.

 

MODERN FOUNDRY

 

Casting a Yankee dryer shell of more than 25 tons in less than 30 seconds requires modern foundry techniques and long experiences, ABK Italia can boast both: the art of the trade has been maintained and transmitted to the younger generations, and state-of-the art equipment has been implemented along by the years to obtain the highest reliability and standards of quality.

 

Thanks to its experiences, capability and technological level, ABK Italian can guarantee Yankee shells with zero defects.

 

MATERIAL

Shell: GJL 30-UNI 1561 cast iron

Heads: GS 400-15-UNI 1563 nodular iron

 

A last generation gas heated furnace allows a perfect control of the casting, to obtain the desired characteristic of body structure, surface hardness, heat transfer, and strength. The alloy composition is controlled by a spectrometric technique, which allow precise and immediate chemical analysis before the pouring of the Yankee cylinders.

 

SPECIAL ACCESSORIES

 

All the Yankee supplied us are complete with their accessories, such as steam and condensate rotary joints and a specially built, double-reduction, hollow shaft gear box.

 

This gear box will be lubricated by a dedicated force oil lubrication unit, which will also serve the Yankee bearing housings.