Today, castings often account for up to 70% of products supplied to the mining, energy and other sectors that have a great impact on the economy. It stands to reason that the casting of high-alloy steel in this day and age requires the use of modern production methods, and advanced casting technology to meet demands for higher-integrity, higher-performance components.
As a leading name in specialist steel foundries in South Africa and internationally, Steloy takes great pride in consistently supplying casting components of improved quality which is backed by the experience of trained technicians and value-added support services, thus meeting the application and quality requirements of the customers and industries we serve.
Centralised solidification analyses and modelling software (MAGMASOFT) is used to cross check conceptual patterns and designs as well as casting methods by running an array of simulations to determine not only casting integrity, but to also predict various quality levels.
CNC Patternmaking & Machining
Simulation data is transferred to our pattern machining centres to produce the required pattern for production to begin. Patterns are cut by one of our two 3-axle Computer Numeric Control (CNC) routers, ensuring accurate and repeatable results.
In addition to the standard pattern production method, Steloy is the first foundry operation in Africa to acquire a multi-functional 5 axis CNC router with a 3 x 4 metre bed that can be used to produce complex direct moulds - something that is not possible with standard pattern-to-mould technology. This direct mould technology allows for large, low volume, casting production while keeping costs down.
Moulding & Casting
Moulding is carried out on cold box machines for castings up to 30kg fettled mass, or by means of the no-bake process for castings up to 2,000kg fettled mass. A shell moulding facility is used for castings to higher tolerances. A fully automatic LP gas fired temperature heat treatment furnace with temperature recorder, coupled to a water quench facility, enables the heat treatment of all grades of castings produced in-house.
Advantages of Simulations
- Realistic and detailed mapping of all process steps
- Quality improvement by avoiding casting defects
- Time savings by creating mould-based solutions
- Cost reductions, particularly in the areas of materials and energy use
- Reduction of start-up costs
- Early and reliable decision-making
- Prediction of mould erosion, sand burn-on and penetration
- Calculation of melt convection during solidification
- Quantification of centerline and macroscopic shrinkage
- Tracking of the development of re-oxidation and sand inclusions
- Crack predictions
To further ensure the integrity of our end product, we recently invested in a fifth optical emission spectrometer. Considered the most advanced in the local foundry industry, the Thermo Electron ARL 3460 spectrometer from Switzerland enables the analysis of an unequalled variety of alloys across a wide spectral range.
Specialised QC Process
Steloy makes use of the Foundry Operation Management and Information System (FOMIS) which allows us to follow a strict quality control system to ensure accurate analysis, documentation and certification throughout the process. This enables the full traceability of our casting products from the quoting stage to delivery of the final product.
Inspection & Testing
All castings are inspected and tested to ensure adherence to the prescribed standards. The following non-destructive testing can be performed:
- Dimensional inspection
- Liquid penetrant inspection
- Radiographic inspection
- Ultrasonic inspection
- Mechanical testing
- Magnetic Particle Inspection
- Pneumatic testing
- Hydro testing up to 30Mpa
- Positive material identification
- 3rd party local and international inspection
- X-ray examination