Production program

Process Equipment to Customer’s or Our Specification

• Equipment for Steel Plants
• Equipment for Hot and Cold Rolling Mills
• Equipment for the manufacture of seamless and welded tubes
• Equipment for tools for the extrusion of non-ferrous metals
• Metal-forming lines
• Hydraulic equipment

We use special tool steels which are made in Meral Ravne using method of ladle and vacuum technology (EAF+VAD) and the process of electric slag remelting (ESR). To satisfy the highest requirements of our customers for quality we also apply steels made using the method of powder metallurgy (PM/HIP)

Forging

• Round bars: Round: ø 90-1000 mm, square: sq. 90-900 mm, length: 2000-10000 mm,
• Discs: external dia.: ø 2500 mm, max. borehole dia.: ø 1800 mm, max. weight: 28 000 kg
• Forgings: dia.: ø 1050 mm, max. length: 10 000 mm, max. weight of a forging: 27 000 kg, conventional: 29 500 kg, ESR, EFS: 24 000 kg, machined: 12 000 kg

Casting

• Castings from 15 Kg up to 10000 Kg
• Steel grades: unalloyed and alloyed cast steel, wear – resistant cast,  steel on the basis of Cr and Mn, special alloys, stainless and corrosion – resistant cast steel
• Cast iron

Rolls for Cold Rolling

Production range: Forced steel rolls:

• Sendzimir Rolls: Dimension: 10 mm to 300 mm; Length of 3000 mm / Material: high alloyed crome – molybdenum steel, high speed steel, ASP powder metallurgical high speed steels.
• Surface hardened rolls: Dimension: 20 to 700 mm/ Length to 6000 mm / Weight of 12000 Kg
• Hardness range (usual): Between 52 up to 67HRC ( 85 – 105 SHc) /Up to 40 mm depth/ Subcooling to -100 °C

Casting Rolls

Manufacture

Moulds are made using state of the art methods and equipment. They are heated in gas-fired drying ovens, while efficient mould coating and chill spraying techniques ensure clean casting surfaces at all times.

Melting

All melting takes place in six main frequency coreless induction furnaces. Chemical composition and temperature are precisely controlled and adjusted by strict checks on the quality of materials. These checks ensure the homogeneous melt essential for continued repetitiveness of the required metallurgical standards.

Spin casting

Horizontal process. The horizontal spin casting machine has enabled the plant to upgrade the quality and reduce delivery times on indefinite chill cast iron and chromium rolls. The system permits extremely precise metallurgical control over roll composition.

Production range:

Up to 1200 mm diameter, Up to 8000 mm length, Up to 35000 kg weight

Materials and quality tables  |  ICDP – spin cast |  Improved ICDP – spin cast |  High – Cromium Iron spin cast |  HSS and SEMI HSS spin cast |  High – Cromium steel spin cast |  Clear Chill static cast |  Nodular cast Iron – static cast |  Nodular Graphitic Steel – static cast |  Other – static cast

Roll covers

• Rubber covers – natural and synthetic rubber
• Composite covers – fibre-reinforced materials
• Polyurethane covers – rotational and vertical casting
• Ceramic, metal and chrome covers

Components Made to Customer’s or Our Specification

• Machine parts (schafts, coilers and uncoilers, large hydravlic cylinders, large bearings)
• Industrial Knives
  

Special hydraulic cylinders

• Hydraulic cylinders for metallurgy
  

Metallurgical equipment

• Equipment for Steel Plants
  

Assembled Rolls

Design and engineering

• KOLDING is proud its know-how and experiance. We invest in R&D and belive in our engineering prowess
  

Quality Control

Business and production processes in the manufacture of rolls are run accordance with ISO 9001:2000 and ISO 14001. Non-Destructive Testing is used to ensure the quality of the material, which include standard non-destructive testing of semi-finished and finisher products made of steel and other materials:

• Ultrasonic testing utilizing the echo-impulse method, portable equipment and manual scanning (EN 10228-3)
• Magnetic powder testing using magnetising sources (EN 10228-1)
• Hardness testing
• Penetrant testing (EN 10228-2)
• In general, Ravne forged rolls are delivered with hardness tolerance +/- 20HV units +/- 1HRc

Ultrasonic and hardness testing

Testing is performed to international standards, costumer specification or internal quality regulations and is made by certified people.

Machining

The machine shop has a wide variety of equipment, custom-built for roll manufacturing. Facilities include roughing lathes, CNC finishing lathes, single head milling machines and grinding machines.

Heat treatment

We provide heat treatment for all steel grades as required by our production programs and business partners.

The service includes:

• Volume heat treatment of steels: stress-relief annealing, soft annealing, diffusion annealing, normalizing, hardening and tempering.
• Heat treatment of steel surface: case hardening, flame hardening, induction hardening.
• Chemical Treatment
• Nitriding ( HV 1000)