Energy saving in the Foundry Industry by Novel Single Shot Melting Process

Lead Research Organisation: Cranfield University
Department Name: Sch of Applied Sciences

Abstract

This project aims to compare the energy used in traditional foundry processes and a novel single shot foundry technology, CRIMSON, and to develop a model of the processes that encapsulates the energy content at each stage. This model can then be used to persuade casting designers to use more energy-efficient processes which consider casting quality as well as design flexibility. The UK retains a globally recognised casting expertise, in copper, aluminium and new light-metal alloys that underpins many competitive, technology-based industries vital to keep the UK's aerospace and automotive base ahead of the competition. These industries draw on advanced R&D work carried out by Birmingham's high-profile Casting Research Group.The University of Birmingham has been at the leading edge of casting R&D for many years. Today, it is internationally acknowledged as a front runner, and the CRIMSON technique - Constrained Rapid Induction Melting Single Shot method - is one such technology which is helping the casting industry make a step-change in product quality, manufacturing responsiveness and energy use.A typical light-metal foundry will tend to work in the following way: from 100 kg to several tonnes of metal is melted in a first furnace, held at about 700 oC in a second, transferred into a ladle and finally poured into the casting mould. It can take a shift (8 hours) to use all the melt in a typical batch and any leftover unused melt is poured off to be used again, or becomes scrap. Quality issues also arise, which must be mitigated: during the time for which the melt is held at temperature, atmospheric water is reduced to hydrogen and oxygen. The hydrogen is highly soluble in the metal at this temperature, but as the casting cools and solidifies, the gas is ejected into bubbles. The bubbles become porosity in the solid casting and have a detrimental effect on performance, therefore, as much gas must be removed as possible from the melt. The oxygen forms a thin layer of oxide on the melt surface, which is then inevitably entrained in the liquid metal when it is transferred between the different furnaces and when the metal is finally poured. The oxide layer (or bi-film) is now an inclusion which, again, has a detrimental effect on the material properties. The longer the metal is held liquid, the more hydrogen is absorbed and the thicker the oxide becomes on the surface.At each stage of the process there are energy losses due to oxidation and furnace inefficiencies, casting yields and eventually scrap. So from an initial theoretical 1.1 GJ/tonne required tomelt aluminium it is possible to estimate that each tonne of aluminium castings shipped will actually use about 182 GJ/tonne.Instead of going through this batch process, the CRIMSON method uses a high-powered furnace to melt just enough metal to fill a single mould, in one go, in a closed crucible. It transfers the crucible into an up-casting station for highly computer-controlled filling of the mould, against gravity, for an optimum filling and solidification regime. The CRIMSON method therefore only holds the liquid aluminium for a minimum of time thus drastically reducing the energy losses attributed to hold the metal at temperature. With the rapid melting times achieved, of the order of minutes, there isn't a long time at temperature for hydrogen to be absorbed or for thick layers of oxide to form. The metal is never allowed to fall under gravity and therefore any oxide formed is not entrained within the liquid. Thus higher quality castings are produced, leading to a reduction in scrap rate and therefore reduced overall energy losses.The first challenge in the project is to measure accurately the energy used at each stage in each of the processes investigated and to calculate the energy losses from oxidation and scrap. The second challenge is to incorporate this information into a model that can be used by casting designers and foundry engineers.

Related Projects

Project Reference Relationship Related To Start End Award Value
EP/G060096/1 21/04/2009 30/04/2012 £514,049
EP/G060096/2 Transfer EP/G060096/1 01/09/2012 31/08/2013 £116,344
 
Description Currently, the completed project objectives are as follows:
1) Objective 1 the measurements have been completed in two conventional foundries: one using cosworth facility/process where gas and electricity are applied, also using gravity sand casting process in Granger & Warral ltd. Another one using crucible furnace where gas is applied and investment casting process in Aeromet ltd.
2) Objective 2will be completed by the PhD student in due time as the work plan (WP2) has scheduled.
3) Objective 3 has been completed for two processes: one is sand casting process, another one is investment casting process.
4) Objective 4 has been completed where all the time and power used by the electric motors of CRIMSON facility are recorded.
5) Objective 5 has been partly finished where the liquid metal in the furnace was measured to assess quality using Prefill Footprinter and Hydrogen probe. The scrap rate for the sand casting process, investment casting process and CRIMSON process have been calculated and measured. Mechanical test and Weibull analysis will be processed when the next stage tests are completed in due time.
6) Objective 6 is partly completed. When the all the planned tests for the sand casting process, investment casting process and CRIMSON process have been completed, the model of foundry will be set up.

6.1 Further Research Activities
The further research activities have been mentioned in section 4. Uncompleted tasks in Objective 2, 5 and 6 will be finished in due time.
Exploitation Route The research could be used to stimulated low energy casing in materials other than aluminium alloys.
Sectors Energy,Manufacturing, including Industrial Biotechology,Transport

 
Description The project has stimulated two further research proposals. One has recently been funded the other is awaiting a decision. Concepts form this work are being used by Depuy Synthes in Cork to manufacture knee implants. The impacts of this research project include the better understanding of the new CRIMSON process and its advantages in making high energy efficiency, reducing GHGs emission and improve casting quality in comparison with the conventional foundry processes. From the both industrial and social point of views, the understanding of the relationship among production process, energy contents and environmental aspect is important to both the engineers and sociologists. The new CRIMSON process has been tested and proved that it can satisfy these high requirements as mentioned above.
Sector Energy,Manufacturing, including Industrial Biotechology,Transport
Impact Types Economic

 
Description Energy Resilient Manufacturing
Amount £233,012 (GBP)
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 03/2015 
End 09/2016
 
Description Energy Resilient Manufacturing 2: Small is Beautiful Phase 2 (SIB2)
Amount £755,750 (GBP)
Funding ID EP/P012272/1 
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 01/2017 
End 07/2020
 
Description Development of concept of Digital Foundry with SME 
Organisation Digital Manufacturing Technologies Ltd (DMT Ltd)
Country United Kingdom 
Sector Private 
PI Contribution Development of system for producing a demonstrator component using AM produced mould and CRIMSON casting process
Collaborator Contribution Production of the AM mould and collaboration with end customer
Impact Ongoing work
Start Year 2019
 
Description A formal working group, expert panel or dialogue - TECHNICAL WORKING GROUP FOR THE EMAS SECTORAL REFERENCE DOCUMENT ON BEST ENVIRONMENTAL MANAGEMENT PRACTICES FOR THE FABRICATED METAL PRODUCTS MANUFACTURING SECTOR 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact This EMAS Working party creates the standards by which companies are audited and achieve Eco accreditation during the Manufacture of Metallic Products.
Year(s) Of Engagement Activity 2017
URL http://susproc.jrc.ec.europa.eu/activities/emas/fab_metal_prod.html
 
Description EU funded project Cradle-to-grave approach to light alloys CRAL: 27th June 2018 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Industry/Business
Results and Impact Brembo, coordinator of CRAL project , together with its partner CANNON, is pleased to invite you to the workshop "Cradle-to-grave approach to light alloys". The workshop is organized in the frame of the EU funded LIFE CRAL project.
Started in July 2016, CRAL project aims to implement a Semi-Solid Metal (SSM) pilot line breakthrough, capable of producing high-quality and light-weight automotive cast components from both recycled low-purity aluminium alloys and new ECO-magnesium alloys in a safe and clean manner.
Year(s) Of Engagement Activity 2018
URL https://allevents.in/provincia%20di%20bergamo/workshop-cradle-to-grave-approach-to-light-alloys/1000...
 
Description TECHNICAL WORKING GROUP FOR THE EMAS SECTORAL REFERENCE DOCUMENT ON BEST ENVIRONMENTAL MANAGEMENT PRACTICES FOR THE FABRICATED METAL PRODUCTS MANUFACTURING SECTOR 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Policymakers/politicians
Results and Impact This EMAS Working party creates the standards by which companies are audited and achieve Eco accreditation during the Manufacture of Metallic Products.
Year(s) Of Engagement Activity 2016
URL http://susproc.jrc.ec.europa.eu/activities/emas/fab_metal_prod.html
 
Description Workshop for Road-Mapping Towards a Sustainable Lower Energy Foundry 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Industry/Business
Results and Impact Road-Mapping towards a Sustainable Lower Energy Foundry workshop took place on the 2nd of December 2015 at Cast Metals Federation (CMF). Foundries and Academic experts from across the UK were invited by CMF and Cranfield University to discuss the challenges and benefits of achieving sustainable lower energy foundries. This research is based on "Energy Resilient Manufacturing (analysis)" through the EPSRC funded "Small is Beautiful" project. The second workshop will be held in July 2016.
To move forward in the short term foundries suggest, to increase awareness of impact across life cycle, introduce life cycle assessment (LCA) tools, use energy audit to assess 'as is' and create future targets for reductions, train people, practice simulation for assessing scenarios, Invest in technology, define a clear business plan and agenda from the top against a time plan.
Medium term they recommend to improve evidential design capability, increase sharing and collaborations, breaking down barriers / increase opportunities to collaboration, develop an inter group / network for sharing and research, stop relying on suppliers to get new information and develop own capability, develop a culture of sharing / innovation / co-production, KPIs, benchmarking between companies and sharing and working in partnership with universities.
In the long term, foundries advice to introduce new technology for rapid prototyping, more tailored, flexible, complete solutions, value added and integrating design. Produce a solution not just manufacturing what the customer asks for. Augmented reality, disruptive technologies, innovate UK funding for projects, understand funding available for innovative projects, changing government legislation, machinery investment, overseas partnership and pressure on companies compliance with H&S and environmental issues.
Year(s) Of Engagement Activity 2015