The company specialises in the manufacture of atomised powders and granulated ferrous products, including stainless steel shot and grit, low carbon steel shot and special purpose alloy powders.

The Ryan family has specialised in the casting of atomised materials for over three decades. Father Terry Ryan being a founding shareholder of Thomas Abrasives, which at the time was a division of Thomas Foundry, began manufacturing low carbon steel shot to supply to both the local and export markets.

Since then the Ryan family have subsequently been involved in various other steel abrasives manufacturing ventures, which are recognisable by the company and brand names Thor Foundry, Sigma Abrasives and Beta Steel. 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. Now having bought out the other family members, they continue to own and operate Sigma Wear Parts, a company that was established in 2012 when the brothers decided to amalgamate the foundry business of Thor Wear Parts and Sigma Stainless Steel, the sister company that manufactured stainless steel abrasive media for the surface preparation Industry.

“Both companies had established markets and clients locally and internationally. The foundry business was established in 2002 and the manufacture of stainless steel abrasives began in 2004,” explained Eddie Ryan.

One area of the plant at Sigma Wear Parts

“Besides the synergies in manufacturing processes a number of other reasons, including cost factors, helped make our decision. We are still manufacturing stainless steel abrasives but we have closed the foundry side. Again it was a decision that involved costs. The foundry did not produce significant tonnage but what we did produce lost out to cheap Chinese imports. The facility is still able to produce castings if required in the future.”

Stainless steel shot and grit
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 now 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 and the only one in South Africa.

“Manufacturing stainless steel abrasives is a specialised process and needs to produce a very spherical product, sub 1.5mm in size. Compared to steel abrasives, the tonnage is not high because it is only used in niche areas where ferrous contamination must be kept to a minimum, for example high-integrity castings in the automotive and aircraft industries,” explained Eddie Ryan.

“Stainless steel abrasive, due to their costs have to be of the highest quality allowing the customer to achieve the desired result at the most economical rate. Having been in operation now for nearly 20 years Sigma is a world leader in this field. The company is also ISO 9001:2015 registered.”

Manufacturing stainless steel abrasives is a specialised process and needs to produce a very spherical product, sub 1.5mm in size. Compared to steel abrasives, the tonnage is not high because it is only used in niche areas where ferrous contamination must be kept to a minimum, for example high-integrity castings in the automotive and aircraft industries

“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.”

“Shot typical applications include preparation of metal surfaces prior to subsequent coating, removal of sand from castings, descaling of steel strips, bars pipes, shot peening and a host of other applications. Industry users include foundries, automotive, aviation, blast/paint contractors, pipeline manufacturers and steel fabricators for example.”

“Grit applications are similar to shot, depending on the desired finish, and include preparation of metal surfaces prior to subsequent coating, surface profiling prior to rubber bonding and lining, removal of sand from castings, descaling of bars and strips. Industry users are very similar except that we can add ship builder and plant maintenance.”

“Stainless steel shot and grit is used in the same applications and industries as steel. However stainless steel shot and grit is more expensive and as a result it is only used where surface preparation and finish are considered for example, safety critical reasons such as in the aerospace and automotive industries or where an aesthetic finish is required.”

“We produce four different grades of stainless steel abrasives and 98% of our production is exported.”

Sigma Wear Parts produce four different grades of stainless steel abrasives and 98% of production is exported. The most recent grade Sigma Wear Parts have developed is named Beta Prime and it is a chrome base stainless, and is fast gaining traction in the German and French automotive industries as well as other industries in Europe. It is mainly used when blasting aluminium castings and pressure die-castings and is gaining acceptance because of its durability, the finish it provides and it has a higher acceptability in the green industry specification and electric car arenas as compared to chrome nickel stainless steel

“The most recent grade we have developed, called Beta Prime, is a chrome base stainless that is fast gaining traction in the German and French automotive industries as well as other industries in Europe. It is mainly used when blasting aluminium castings and pressure die-castings and is gaining acceptance because of its durability, the finish it provides and it has a higher acceptability in the green industry specification and electric car arenas as compared to chrome nickel stainless steel. We still manufacture chrome nickel stainless steel abrasives.”

Revitalisation of the manufacture of low carbon steel shot
“When we established Sigma Wear Parts we were still manufacturing low carbon steel shot and continued to do so for a number of years. But again cheap imports got to us and we continued just with the stainless steel abrasives.”

“However, in view of recent developments in South Africa when the only manufacturer closed its plant there was a void left. We have the know-how and equipment so we have decided to go back into manufacturing low carbon steel shot.”

“Just over two years ago we installed a new 3 ton furnace so we have the capacity and South Africa needs a local producer, especially as imports have seen a significant rise in prices.”

Atomised metal powders
“We have a large manufacturing capacity for producing ferro Silicon 14-16 % dense medium separation medium powders.”

“The process and development of both the milled and atomised versions of this product were carried out by our sister company Samarium SA, who have also been instrumental in the development and design of all our manufacturing processes.”

Sigma Wear Parts have been manufacturing dense medium separation (DMS) powders for a number of years

“We have been manufacturing the powders for a number of years now. The initial production process is very similar to manufacturing our other abrasive products in that it involves granulation or atomisation.”

In addition to the ferro silicon powders, Sigma, through Samarium SA, operates a specialised R&D facility producing small batches of custom powders of various compositions.”

“In general, we market and sell via a local and international distributor network that has been established over the 22 years we have been in business.”

For further details contact Sigma Wear Parts on TEL: 011 823 4443 or visit www.teamsigma.com.au