Metallurgical 100 T 22 CBM Cast Iron Slag Pot and slag ladle for steel plant

CITIC IC is a modern industrial China group specialized in the producing of heavy plates in low-alloyed carbon steel grades. Organised as full integrated works, the major production facilities include cokery plant, blast-furnaces, oxygen steelplant - equipped with BOF-converters, secondary metallurgy, vacuum degassing, continuous and ingots casting - and plate mills. Complementary to the core business, a "down-stream" manufacturing unit is available as a branch of the Heavy Fabrication: it is mainly focused on the supply of slag-pots made out of cast-steel (GS) everywhere the emphasis is placed on large buckets in capacity up to 45 m³

(1.575 cu. feet).

The expertise of CITIC IC arises from its privilege to be both user and manufacturer of slag pots. The extensive experience gained in designing and engineering slag-pots is primarily based on the pots operating at the own steel plant and secondly on about 3.000 items produced over the 40 last years also in co-operation with manufacturers of slag pot carriers and service providers to metallurgical industries.
The Dillinger slag pots are operating worldwide whereverreliable tools are required for the disposal of molten or solid slag which arises from metallurgical or chemical processes.
Heavy Fabrication Division

Product definition
The product covered here is a load-bearing device whose sole purpose is to collect molten or solid slag generated during metallurgical or chemical processes, to retain it during transport and to deposit it at a place of disposal.
Slag pots are crucial items as they are part of a lifting equipment and therefore undergo in terms of mechanical design engineering and handling the national safety regulations of the state where they are supposed to be operated. The design of the Dillinger slag pots intended to be used within the European Community meets the requirements ofthe European Machinery Directive 2006/42/EC: every slag pots is supplied with the CE conformity marking.

Material
The pots are made out of the cast-steel DICAST, trade name owned by CITIC IC for castings: this material is similar to the steels A27/A 27M grade 65-35: April 2003, BS 3100 A1/A2: January 1991 or GS 20Mn5 to DIN 17182: May 1992. DICAST is a fully killed steel, vacuum-degassed and processed to a fine grain size structure with improved properties both in toughness and in elongation.
• Chemical compositionverified on product Elements C Si Mn P S
Required ≤0.23% ≤0.55% ≤1.65% ≤0.025% ≤0.025%
Typical 0.17% 0.40% 1.45% 0.015% 0.002%
• Mechanical propertieschecked at room temperature in the delivery condition i.e. after completion of the quality heat treatment from cylindrical cast-on test blocks (∅60 mm x 250 mm) available on every slag pot: both the sample preparation and the testing comply with ASTM A 370-96.
Properties Rm Reh
A KCV ( average of 3 specimens / individual ) Required ≥450 MPa ≥240 MPa ≥20 % ≥55 J / 39 J
Typical 490 MPa 280 MPa 30 % 120 J / 85 J
• Delivery condition: normalised
Note regarding the material selection: due to obvious advantages in terms of service life and maintenance cost-efficiency, cast steel has been becoming more significant in the slag pot construction over the last years versus both materials, spheroidal cast-iron and lamellar graphite cast-iron. In contrast to other materials, cast steel offers excellent repair possibilities as it is well-suited to welding.
Manufacturing
Except the supply of the forgings for trunnions and the engineering of the pattern, all further operations are carried-out at the in-house foundry plant.
• Moulding
the castings are manufactured in a workman-like manner as required in the China standard DIN EN 1599-1: August 1997, ruling the delivery conditions ofcastings. The moulding is individually carried out within a modular flask by using a sand preparation based on resin bonding.
• Trunnions
the trunnions - when any - are preferably cast-in:they are as a rule manufactured from the steel material S355 J2G3 to DIN EN 10250-2: December1999 and forged as per DIN 7527 February 1975.
Cast-on or hot-fitted trunnions can be also provided.
• Melting
the melting is carried out in the oxygen steel plant ( 2 off 180 t BOF converters ); the ladle capacity allows a continuous bottom pouring process the speed of which is permanently controlled. The metal analysis is checked by using a computer linked spectrograph.
Heavy Fabrication Division
• Heat treatment
every pot undergoes a combined quality heat treatment (annealing) aiming both to grain refining and to stress relieving i.e.:
- heating to a temperature above AR3, austenitising at about 915°C and controlled cooling in furnace
- intermediate holding at 600°C - 630°C and completion of cooling in furnace down to 300°C
• Fettling and dressing
The inner surface is processed fit-for-purpose so that the surface discontinuities - which might cause some sticking of the slag - are extensively removed. Additionally, the castings are descaled by shotblasting and the outside is additionally coated for transportation.
The surface quality results from the comprehensive practice of the manufacturer qualified by the requirements of MSS SP-55-1996 (Visual Method for Evaluation of Surface Irregularities).
Quality assurance
The fabrication route is governed by the provisions of the implemented Quality System ISO 9001: 2000.
The standard documentation ensures the full traceability of every process step:
• Manufacturer test certificates according to DIN EN 10.204 § 3.1 including chemical composition, mechanical properties and non-destructive examination;
• Dimensional check supported with a “as-built“ sketch;
• Record of the quality heat treatment;
• Documentation required by the Machinery Directive 2006/42/EC (when applicable).
Design
The slag pots can either be manufactured in accordance with a well-tried and proven concept provided by the commissioner or be customised to the specific requirements resulting from the operational environment. The range of the available design reaches from conventional to most advanced buckets. Slag pots are wearing products exposed to both mechanical and alternate thermal stresses the extent of them depends on the service conditions. An accurate design aims to minimise the impair of the operative environment on the service life: however, it remains always a compromise taking into consideration both physical and economical aspects, resulting in a variety of shapes tailored to the site operations.
A comprehensive data bank resulting from the previous experiences combined with a proper software implementing the Finite Element Analysis serves the individual design optimisation.
Service philosophy
The marketing strategy of CITICIC is to enjoy the direct contact to the slag pot operators and to establish a long-terms relationship for mutual profit.
Slag pots are more than just disposable products: we endeavour to propose options in terms of design engineering in taking advantage of our double experience as manufacturer and user, always targeting the optimisation of their service life.
Skill with slag pots
Further information on delivery programme as well as useful advises on product, design, material and application are provided by the customer service team of the foundry department: it will support you actively in helping you to elaborate the right solution.