The company specialises in the manufacture of high integrity castings and the manufacture of atomised stainless steel shot and grit and low carbon steel shot.
“I suppose it was inevitable that I would get involved in the foundry industry from an early age. My late dad Terry Ryan was a foundryman all his life and through his influence I started to work in the foundry industry from the age of 14,” said Eddie Ryan, who is a partner with his brother Andrew in Sigma Wear Parts.
Manufacturing stainless steel abrasives is a specialised process and needs to produce a very spherical product, sub 1.5mm in size. The tonnage is not high because it is only used in niche areas where contamination must be kept to a minimum, for example high integrity castings in the automotive and aircraft industries
“I can’t believe that it was 40 years ago that I first started to help with the metal sampling and analysis at J&C Malleable, the company that my dad was working for at the time. I was given the opportunity to earn a bit of money during my school vacations and I soon realised that school was not for me. Unfortunately I was only allowed to leave school until I was 17. Until I reached that age I continued with my vacation job. The added bonus was that I was given an opportunity to work in the different departments in the foundry.”
Stainless steel abrasive volumes are low as compared to carbon steel abrasives because of cost but what clients don’t realise is that stainless steel abrasives have a much longer life span
“I eventually settled on pattern making and qualified as a patternmaker at the age of 21. I did various courses in foundry practice and metallurgy at college, which helped me become the foundryman that I am today.”
Sigma Wear Parts
“The company name – Sigma Wear Parts – is relatively new. It was only formed 18 months ago when we decided to amalgamate the foundry business of “Thor Wear Parts” and “Sigma Stainless Steel”, our sister company that manufactures stainless steel abrasive media for the surface preparation Industry,” explained Eddie.
“Both companies have established markets and clients locally and internationally. The foundry business was established in 2002 and the manufacture of stainless steel abrasives began in 2004.”
Sigma Stainless Steel
The Ryan family has specialised in the casting of atomised materials for over three decades.
Terry Ryan was instrumental in forming Thomas Abrasives, which at the time was a division of Thomas Foundry, and began manufacturing low carbon steel shot to supply to both the local and export markets.
In March the foundry installed a 100 kilogram furnace equipped with an Inductotherm Power-Trak 125-30R power source. This unit forms the heart of the new R&D facility. This furnace also allows the company to perform a specialised service in that Sigma Wear Parts can now offer a quick turnaround time for those urgent one-off castings and low volume castings in non-standard metal such as inconel and barium bronze. The size of this furnace dictates the weight of the casting – a maximum of a 50 kilogram net weight. Sigma Wear Parts will be able to manufacture castings in most metals from this unit
Since then the Ryan family have subsequently been involved in various other steel abrasives manufacturing ventures. To date they have designed, built and commissioned five abrasive manufacturing plants. Brothers Andrew and Eddie have been integral members of the family businesses since inception.
A natural extension of the experience and expertise gained from the various manufacturing processes utilised by the family was to start manufacturing stainless steel shot and grit in South Africa. Thus Andrew and Eddie started manufacturing stainless steel abrasive products under the Sigma Stainless Steel Abrasives label in 2004.
The company is a leading exporter of cast stainless steel abrasives to a very demanding European market. Again the company has proved its resilience and commitment to product innovation and is today a leading manufacturer of these products in the world.
“Manufacturing stainless steel abrasives is a specialised process and needs to produce a very spherical product, sub 1.5mm in size. The tonnage is not high because it is only used in niche areas where contamination must be kept to a minimum, for example high integrity castings in the automotive and aircraft industries,” explained Eddie Ryan.
“Stainless steel abrasive volumes are low as compared to carbon steel abrasives because of cost but what clients don’t realise is that stainless steel abrasives have a much longer life span.”
“Other advantages of why cast stainless shot is a popular product for cleaning and deburring aluminium or non-ferrous parts in air or wheel blast applications, is that it produces very bright surfaces and is ideal for producing finishes free from ferrous residue and it is available in very small sizes.”
The foundry floor
“The combination of proper abrasive type and size, along with air blast or wheel blast equipment selection, can produce finishes ranging from a very deep profile to provide an anchor pattern for heavy coatings, a clean, bright, cosmetically pleasing finish without metal removal and a finish stripped of coatings on composite materials without damage to the delicate underlying surface.”
Low carbon steel shot
Although the company slowed down manufacturing low carbon shot over three years ago due to economic reasons such as the high cost of energy input, the strengthening of the Rand at the time, the high price of scrap and the increasing demands of labour, which all led to the product becoming less competitive, it has ventured back into this market but on a much smaller scale.
“We have over 40 years of collective experience in low carbon technology and offer a product meeting and exceeding SAE J2175 and J444 standards. Low carbon shot has a bainitic microstructure, achieved by meticulous raw material selection, constant monitoring of metallurgical chemistry and a controlled atomisation process. Abrasive durability has been reported up to 20% higher than standard high carbon shot with no loss of cleaning efficiency,” explained Eddie.
Two three ton 2000 kilowatt fast melting furnaces drive the production department in the abrasive manufacturing division. The atomising unit and process is unique to and specially designed by the company.
Dedicated product processing lines consisting of retrieval, screening, crushing, classifying and packaging, exist for the different products produced by the company.
The foundry has two 500 kilogram furnaces, a 5-ton an hour Omega mixer that has been fitted with an auto blend unit and they are currently installing an Omega sand reclamation plant
All products are issued with a quality control certificate and traceability records are stringently kept.
The foundry – Thor Wear Parts
In 2002 the family added a specialised foundry to the manufacturing mix, concentrating on small specialised castings for a select customer group. The vision was to build close relations with a small group of customers whereby optimum quality and service could be delivered. This strategy has proved very successful with the company seeing growth in both turnover, profit and output in every year since inception, despite the severe impact of the financial crisis.
“With my late Dad, Andrew and I having gained extensive experience in the foundry environment prior to focusing our attention on abrasive manufacturing it was not long before we had the inclination to see molten metal poured into moulds again as opposed to molten metal following the atomising process. Once it’s in your blood you can’t get rid of it,” said Eddie Ryan.
“We received an enquiry for high chrome replacement castings for shotblasting equipment. We had a spare furnace and floor space so it was a matter of sourcing the ancillary equipment and materials that would be needed to start a foundry.”
Moulds that have been prepared
A selection of castings made by Sigma Wear Parts
“In the beginning the foundry was not our priority but as further enquiries came in we took it more seriously and it has evolved into a fully-fledged foundry that has a current capacity of 140 tons per month.”
“We can manufacture castings up to three and half tons net weight per casting using the furnaces in the stainless steel abrasives division.”
“The typical castings that we manufacture include a range of precision components for rotary turbines, paper mill refiner plates, pumps and a whole host of wear parts including crusher spares and some high integrity cast components for the railway industry.”
“The mix of materials is made up of 70% high chrome castings with the rest made up of SG iron, stainless steel and cast iron and to a lesser extent the non-ferrous metals.”
“Recently we added an aluminium casting line that has proved very successful and now delivers very high integrity aluminium castings in various aluminium alloy grades.”
“On the equipment side we currently have two 500 kilogram furnaces, a 5-ton an hour Omega mixer that has been fitted with an auto blend unit and we are currently installing an Omega sand reclamation plant.”
“The laboratory is equipped with a Spectro SpectroMax spectrometer. With it we are able to determine all of the elements used in the cast metal industry, including trace analysis of carbon, phosphorous, sulfur and nitrogen. Our laboratory can analyze all base metals including iron, aluminium, copper, nickel, cobalt, titanium, zinc and lead. Every heat that is melted in our company is analyzed and the results recorded for full traceability.”
The foundry philosophy
“Our philosophy for the foundry is to offer our customers a quality service and to produce high quality castings consistently. Typically we engage ourselves with specialised and more difficult castings, and exciting processes. We like to look at ourselves as the complete cast engineering solution providers.”
“But to portray yourself as this type of business you have to have the equipment that can back-up your statement.”
The Haas VF 3 CNC vertical machining center is used to test, run and enhance current and new castings, tool designs and patterns. Highly dimensionally accurate patterns can be manufactured in the patternshop and on the Haas CNC machining center
The Renishaw Cyclone contact scanner provides the company the opportunity to do direct CAD output for reverse engineering, CAM output to machine components and a host of measuring and inspection capabilities
“In this respect for a number of years we have had a Haas VF 3 CNC vertical machining center to test, run and enhance current and new castings, tool designs and patterns. Highly dimensionally accurate patterns can be manufactured in our patternshop and on our Haas CNC machining center for our customers.”
“We use Solid Edge CAD software to design and develop castings and tooling and we use EdgeCam as our machining software. I must emphasise that this machine is not a production machine. It is used purely for new development and enhancing existing castings.”
“Standing next to the Haas is a Renishaw Cyclone contact scanner which provides us the opportunity to do direct CAD output for reverse engineering, CAM output to machine components and a host of measuring and inspection capabilities.”
“Last year we purchased uPrint SE 3D printer manufactured by Stratasys. It offers a low-cost, networked alternative for printing functional 3D models and tools from the desktop. The printer builds models layer-by-layer using ABS plastic. The uPrint SE 3D printer enables us to evaluate design concepts and test models for form, fit and function.”
“These add on services have been hugely beneficial in our quest to be the complete cast engineering solution providers.”
New Inductotherm Power-Trak 125-30R and furnace
“We have now taken this philosophy a step further in our service offerings. In March we installed a 100 kilogram furnace equipped with an Inductotherm Power-Trak 125-30R power source. This unit forms the heart of our new R&D Facility.”
“This furnace also allows us to perform a specialised service in that we can now offer a quick turnaround time for those urgent one-off castings and low volume castings in non-standard metal such as inconel and barium bronze. The size of this furnace dictates the weight of the casting but we are looking at a maximum of 50 kilogram net weight. We will be able to manufacture castings in most metals from this unit.”
The Spectro SpectroMax spectrometer determines all of the elements used in the cast metal industry, including trace analysis of carbon, phosphorous, sulfur and nitrogen
Dedicated product processing lines consisting of retrieval, screening, crushing, classifying and packaging, exist for the different products produced by the company
Sigma Wear Parts operates from a 4000 m² facility in Lilianton, Boksburg, Gauteng with the stainless steel shot and grit and the low carbon steel shot manufacturing operations housed in one factory, the foundry operations in an adjoining factory and the development and research equipment in another factory.
Currently the company employs 45 staff with 25 in the foundry division and the company has a Level 3 BBEEE rating.
The company is fully compliant with the current local and national environmental legislation governing all the processes carried out on site.
For further details contact Sigma Wear Parts (Pty) Ltd on TEL: 011 823 4443