EMA is qualified to produce superalloys components for aerospace or gas turbine, using the equiaxed, directionally solidified and single crystal technologies. EMA is using investment casting production methods, with the goal to obtain a metal part containing:
EMA warranty a large series flexible production. EMA is always working to continually reduce the lead time and time per product and to increase the efficiency and productivity.
In every Department, every single component to be produced is always subjected to the EMA Implementation Operative Program. This programm is leaded by the technical engineering together with operators to
Our goal is to warrantee the high quality standards to the customer during the time. The EMA Departments personnel is fully trained and the continuous up grade is the basic EMA politics to maintain the high quality standards all over the production cycles.
Turbine components provided with internal cavities for cooling or for lightening require a ceramic core inside the wax model. This core is removed after casting by chemical etching.
The wax patterns of these special turbine components (cored) are injected in WAX Area in one solution in dies provided by core housing.
The ceramic cores used in EMA for components with equiaxed (EQX), directional (DS) and single-crystal (SX) grain structure have dimensions ranging from a few centimeters to 70 cm, with different and highly complex geometries.
The operations performed on the ceramic cores within this production Area are finishing, impregnation with a material that ensures the increment of the mechanical resistance during wax injection, CMM and GOM (3D industrial scanner) dimensional inspection, preparation for wax injection (e.g. spacers (chaplets) insertion, partial filling with wax, core-wax adherence optimization) and visual inspection for verifying their integrity and compliance with the quality specifications.
A wide range of components and therefore of wax patterns are currently produced in EMA with weights ranging from some grams up to 5 kg, lengths from 50 to 800 mm and thicknesses that in some cases do not exceed 0.5 mm.
Wax Area is equipped with a series of semi-automatic systems for wax injection into steel/aluminium dies for the manufacturing of the wax patterns of the final components. These systems ensure the control and monitoring of the thermo-fluido-dynamic production parameters during the whole wax injection process. In particular, the main process variables are subjected to a continuous control by means of complex feedback systems in order to ensure the stability of the injection process so that full compliance with the set standards and high product quality are always guaranteed.
The wax patterns thus manufactured are then manually processed on workbenches equipped with the most modern tools for components finishing and preparation to subsequent process operations. Subsequently, the wax patterns are subjected to a series of non-destructive tests such as visual inspection, digital X-ray inspection, dimensional measurements with CMM machines, optical scanning of the whole pattern with newest GOM cameras based on Blue Light Technology, wall thickness measurement by means of Ultrasonic Thickness Gauges to verify their compliance with the quality standards. The wax patterns are then assembled in a variable number, according to their type and dimension, on specific assemblies in order to increase the production efficiency in terms of raw and ancillary materials and productivity.
The environmental thermo-hygrometric conditions of the Wax Area (temperature and relative humidity) are in-line monitored to guarantee the dimensional stability of the wax patterns during their permanence in this production Area.
The Shell Area is equipped with 6 robotic cells for automatic application of ceramic layers for the manufacturing of highly performing shells.
The robotic cells offer maximum working flexibility so that there can be produced a wide range of shells in terms of:
The anthropomorphic robots (6/7 axis) are of the latest generation and guarantee accurate and delicate (vibration-free) handling of small and large wax assemblies. All rotary tanks containing ceramic slurries are equipped with automatic-lids and cooling paddles to avoid contaminations and maintain a controlled slurry temperature.
The rotary and vertical rain cabinets guarantee an uniform stucco powder distribution onto the wax assemblies.
All the ceramic slurries are prepared by means of an automatic mixing plant that ensures the transfer and mixing of the various constituent materials (i.e. binders, refractory powders, wetting and antifoaming agents) in automatic mode.
All the ceramic slurries are regularly checked during their use in production by measuring a series of physico-chemical characteristics (e.g. viscosity, plate weight, temperature, pH, total solids, silica content, specific gravity, gel test).
The granulometry of the incoming stucco powders are regularly checked.
In order to guarantee the stability of the shell manufacturing process, the control systems of the Shell Area ensure, through complex feedback systems:
Continuous development activities are carried out for the selection of new, increasingly performing materials and new in-line measuring instruments.
The Furnace Area is divided into two macro-areas:
- internal cleaning of the ceramic mould/shell by means of vacuum technique and water washing to ensure the complete removal of all debris that can be potential causes for metallurgical defects
- integrity control of the ceramic mould/shell by using tracers able to intercept even the most imperceptible cracks
- application of insulating blanket onto the ceramic moulds/shells of the equiaxed components with size and shape guaranteed by CAD/CAM cutting machine;
The equipments used for the casting, the real heart of our manufacturing process, are of three kinds:
- Resistive furnace for high vacuum casting of small dimension components (up to 10 kg per cast) by using the Bridgman controlled solidification in single crystal or multigrain structure.
- High vacuum induction furnace for casting mediante un processo di tipo tilt pouring components up to 70 kg per casting with equiaxed solidification; each furnace is feeded by a dedicated pre-heat furnace
- High vacuum induction furnace for casting , mediante un processo/tecnologia di tipo Bridgman, components up to 32 kg per cast on big assemblies, and with controlled solidification, single or multi grain.
All the equipments are provided with feedback systems for the control and recording of each casting key process parameters such as vacuum level, temperatures, pouring velocity, withdrawal velocity. All furnaces are integrated to a manufacturing execution system that ensures the possibility to access the on going casting activities from any computer workstation within the factory and to monitor, at any moment, the castings key parameters and eventually correlate them with any other process parameters and with the results of the post cast non-destructive controls.
The POST CAST area is done up the following cells:
The Investment Casting Modelling is performed in EMA to support two key Manufacturing Engineering processes:
- Product Introduction by the research and definition of optimal and robust combination of main process parameters, enabling reduced time and cost for the new component development;
- Continuous Improvement by yield increment and cost reduction activities.
Investment Casting Modelling is applied to the production of components with directional, single crystal and equiaxed grain structure.
The ceramic shell heating and filling with alloy as well as the casting solidification processes are simulated by the application of finite element method (FEM), using QM00 proprietary software and ProCAST software. In this way thermal and mechanical induced defects, specific to each process configuration modeled, are predicted.
Using Casting Modelling, different process methods can be developed, tested and optimized within virtual environment, reducing the number of physical casting trials, by the variation and trialling of such items as:
- part and core geometry;
- assembly geometry;
- shell material and thickness;
- alloy material;
- casting programs.
All the production components are submitted to metallurgical and dimensional checks to ensure the compliance to the pattern and to the specifications.
In the list of the metallurgical checks we can find the NDT (visual inspection, x-ray and penetrant test) and the check for the grain structure, a non-destructive method, used on metals, for testing the structural indications visible on the surface after selective etching, in an illuminated room with visible radiation. The method for visual grain inspection allows to highlight indications through contrast.
In the dimensional inspection group we can also find the checks go / no go (profile scan, gauge, calliper clock, calliper ect..) and the checks with Coordinate Measuring Machine (CMM) and with Structured Light (GOM). Moreover, in case of castings with cooling passages, wall thickness is measured by ultrasonic technique.
In case of particulars components, it is possible to perform further test, for example measure of air/water range, inspection of the cooling passages, conductivity test.. The high precision machines used for the dimensional tests, together with tools monitored periodically by visual inspection and by metrological checks, ensure the production of components of excellent quality.
The EMA laboratory has all the necessary equipment to perform metallographic and chemical testing of the castings products and process in order to meet the validation requirements, production check and detailed root cause analysis. . Both metallographic and chemical analysis have Nadcap accreditation and customers approval. All the mechanical testing are performed by outside by approved laboratories.
The main metallographic equipment are:
The main equipment for alloy chemical analysis are:
The main equipment for the chemical-physical analysis of the other materials used are: