Our company offers the slag pots made out of cast-steel with the capacity up to 45m3 (1.575 cu. feet).
The extensive experience gained in designing and engineering slag pots is primary based on the pots on about 3’000 items produced and delivered to our customers over the 20 last years also in cooperation with manufacturers of slag pots carriers and service providers to metallurgical industries.
The slag pots delivered by our company are operated worldwide wherever reliable tools are required for the disposal of molten or solid slag which arises from metallurgical or chemical processes.
The product covered here is a solid-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 the 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 slag pots are made out of the cast steels which are fully killed, vacuum degassed and processed to a fine grain size structure with improved properties both in toughness and in elongation.
The mechanical properties are checked at a room temperature in the delivery condition i.e. after completion of the quality heat treatment from cylindrical cast-on test blocks (Ø 60mm x 250mm) available on every slag pot: both sampling preparation and the testing comply with ASTM A 370-96.
Note regarding the material selection: due to obvious advantages in terms of service life and maintenance cost-efficiency, the cast steel became 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.
Except the supply of the forgings of the trunnions and the engineering of the pattern, all further operations are carried-out at the in-house foundry plant.
The castings are manufactured in a workman-like manner as required in the standards ruling the delivery conditions of castings. 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: as a rule they are manufactured from the steel material S355 J2G3 to DIN EN 10250-2 and forged as per DIN 7527. Cast-on and hot-fitted trunnions can also be 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 computed linked spectrograph.– Heat treatment
Every pot undergoes a combined quality heat treatment (annealing) aiming both to grain refining and stress relieving i.e.:
- Heating to a temperature above AR3, austenitising at about 915oC and controlled cooling in furnace,
- Intermediate holding at 600oC-630oC and completion of cooling in furnace down to 300oC.
– Fettling and dressing
The inner surface is processed fit-to-purpose to that the surface discontinuities – which might cause some sticking of the slag – are extensively removed. Additionally, the castings are descaled by shot-blasting and the outside is additionally coated for transportation.
The surface quality results from the comprehensive practice of the manufacturer qualifies by the requirements of MSS SP-55-1996 (Visual Method for Evaluation of Surface irregularities).
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.
The slag pots can either be manufactured with a well-known and proven concept provided by the Buyer or be customized to the specific requirements resulting from the operational environment. The range of the available design reaches from conventional to most advanced buckets.
The 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 minimize 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 optimization.
The marketing strategy of our company is to enjoy the direct contact to the slag pot operators and to establish a long-term relationship for mutual profit.
The slag pots are more than just disposable products: we endeavor to propose options in terms of design engineering in taking advantage of our double experience as manufacturer and supplier, always targeting the optimization of their service life.