Finishing stainless steel blanks, tube and pipe efficiently

If you think about fabricating steps in order of process, you probably think about finishing as the last stage. Short of a final inspection and packaging, it is last. Furthermore, in many shops, finishing is an entry-level position, and although the process isn't quite an afterthought, a nice appearance usually isn't as critical as everything else that goes into a successful product—research, design, prototyping, testing, and so on. On the other hand, if you told Jose Mao-Cheia you thought about finishing last, he might just tell you that you’re thinking it through backward.

Jose Mao-Cheia is the owner of Stainless Accessories. Established in 1998, the company head office and factory is located in Nelson Mandela Bay, providing logistical access to other major Southern African centres by road, as well as to export markets by air and sea.

Historically Stainless Accessories was a manufacturer of automotive accessories for the export market. All customers were in the aftermarket sector and exports were done to the USA, Canada, United Kingdom, the Scandinavian Peninsula and Israel. Mirror finished stainless steel exhaust tips formed the bulk of the product range and were manufactured using automated equipment designed and built in-house, as well as specialised buffing techniques. These products have been displayed at various automotive speciality products trade events around the world, most notably SEMA.

Stainless Design has developed a concept of reinforcing tubing to exceed the strength of the equivalent diameter solid stainless steel bar, resulting in a better quality product at a significantly lower cost. Various features of these developments are now protected internationally by patents and patent applications, as well as the features of the design and construction

Stainless Accessories’ dedication to investing in technology is evident across the shop floor. A case in point is blanking. The company does a lot of blanking work with a production capacity of 530 000 per month. It is estimated that capacity of the existing facility could be increased to one million per month

Stainless Accessories currently has four blanking lines, three of which are dedicated to shell blanking

After two years of business the scope of manufacture was increased to include the tubes required for the production of exhaust tips. These tubes varied in diameter from 76.2mm to 101.6mm and were made up to 610mm in length.

Due to the volatility of our South African currency management started investigating alternative markets and products where their existing expertise in stainless steel fabrication and equipment could be utilised.

Over the next few years the company's core business shifted to the manufacture of catalytic converter shells and they gradually pulled out of the export market.

Stainless Accessories’ first catalytic converter shell was manufactured in December 2004 as a result of securing a contract with the Port Elizabeth facility of Faurecia, one of the world's leading automotive component suppliers for emission control technology. This contract was followed up with another contract with exhaust technology company Eberspächer, in September 2005.

ISO 9001/2000 accreditation was achieved by the company in the same year (2005) and by April 2006 the company was manufacturing one million components per annum. This figure rose to two million in 2007, three million in 2008 and six million by November 2011. Currently the company manufactures 7,2 million catalytic converter shell components per annum, and besides Faurecia and Eberspächer now boasts Tenneco, VWSA and Bentler as clients.

2006 also saw the company achieve ISO/TS 16949 accreditation, an important quality management system in the automotive industry.

The establishment of Stainless DesignFrom 2005 onwards, the company's core business had shifted to the manufacture of catalytic converter shells. However during this time, the experience gained in the fabrication and mirror finishing of stainless steel products was used in the design and development of a self locking balustrade system. Initial design and prototype development commenced in 2007, with 2008 and 2009 focusing on aesthetic improvements, simplification of assembly and automation of production. During the period Stainless Design, a company formed to manufacture and market the self locking balustrade system, along with their development partners, completed several commercial and residential developments while refining the product and installation methods.

As of July 2009, the patented balustrade systems were ready for broad marketing and Stainless Design began developing a network of installers.

Today Stainless Design can showcase commercial and residential installations around the globe and has sales distribution and installation centres throughout South Africa, South America (Brazil), Mauritius and Europe (Sweden).

The fourth blanking line, which was recently commissioned, can accommodate coils up to 800mm wide

Once the coil is processed through the blanking lines it then moves onto 25 different welding and finishing stations before moving on to final checking, packaging and dispatch. Each welding station has its own dedicated welding configuration, which have been built in house

The latest acquisition, installed earlier this year, is a Samsung Machine Tools PL2000SY CNC turning center which has a maximum turning diametre of 360mm, turning length of 520mm, a Y-axis travel of ±50mm and bar-work capacity of Ø65mm. The machine has a subspindle and driven tools with through tool coolant

"One big challenge in stainless steel tube finishing is the growing expectations about the surface finish. Tools and abrasives have improved to achieve better surface quality in less time. At the same time, fabricators require finishing methods that address health, safety, and environmental concerns," explained Mao-Cheia.

"As the use of stainless steel has expanded into new applications, many tube fabricators are finishing stainless steel for the first time. Some are just experiencing its hard, unforgiving nature, while also discovering how readily it is scratched and blemished. In addition, because stainless steel is priced higher than carbon steel and aluminium, material cost concerns are magnified."

"Even those already familiar with stainless steel's unique properties are encountering challenges because of variations in the metal's metallurgy."

"Expectations for the finish quality have grown more demanding, industry leaders say, in part because the use of stainless steel is growing in the food, pharmaceutical, and chemical processing industries, in which tube interiors are often required to have a mirror finish."

"Also, because stainless steel is rarely coated or painted, it is, by its very nature, an appearance metal. Therefore, expectations for the final finish are high."

"Demand has surfaced for the ability to achieve a high-quality finish on tube after it has been bent and fabricated."

"As with all types of manufacturing, tube fabricators are pressured to find ways to decrease downtime, look for lean efficiencies at every turn, and shorten the manufacturing process overall to reduce costs."

High expectations"Because stainless steel is inherently corrosion-resistant, no additional coatings or finishes are needed. There is however a misconception that stainless steel is maintenance free. The amount of maintenance required, if any, is dependent of the grade of stainless steel used, the consciousness of the environment in which it is installed and the surface finish of the product.

Virtually all stainless steel balustrade installations done inland have a brushed surface finish and use Grade 30L SS.

In a highly corrosive environment such as external installations in coastal regions grade 316 stainless steel is used, but more importantly the product surface is of a polished finished.

Stainless Design utilises automated machinery that was designed and manufactured in house to attain a perfect mirror finish on its modular balustrade system, radically reducing the maintenance required in corrosive environments.

Stainless steel balustrades"Stainless Design specialises in manufacturing and installing unique modular systems for industrial and residential applications. We currently hold several patents on a range of railing products that utilises interference fit technology to create a modern aesthetic system that is rigid, robust and structurally sound, and requires no welding in the production, assembly and installation."

Structural elementsStainless Design has developed a concept of reinforcing tubing to exceed the strength of the equivalent diameter solid stainless steel bar, resulting in a better quality product at a significantly lower cost. Various features of these developments are now protected internationally by patents and patent applications, as well as the features of the design and construction.

EquipmentStainless Accessories’ dedication to investing in technology is evident across the shop floor. A case in point is blanking. The company does a lot of blanking work with a production capacity of 530 000 per month. It is estimated that capacity of the existing facility could be increased to one million per month.

Stainless Accessories currently has four blanking lines three of which are dedicated to shell blanking. These lines exceed the output of the factory and comfortably run a single shift. This contingency of having three lines facilitates production in the event of a breakdown.

The fourth blanking line, which was recently commissioned, can accommodate coils up to 800mm wide.

"This enables us to blank much larger shell blanks in house without having to outsource this process thereby reducing our costs. This also enables us to process coil for large diameter shells of varying lengths with a single blanking tool," commented Mao-Cheia.

Stainless Design now machines most of its components for the stainless steel ballustrades

Installed last year was a C-Tek CNC milling machine, a C-Tek spark-eroding machine and an Akira-Seiki Performa V5.5 CNC machining centre, all supplied by MJH Machine Tools through their agent in Port Elizabeth Wam Engineering

The C-Tek spark-eroding machine

Once the coil is processed through the blanking lines it then moves onto 25 different welding and finishing stations before moving on to final checking, packaging and dispatch. Each welding station has its own dedicated welding configuration, which have been built in house.

Until recently Stainless Accessories was running two tube mills with the capability of producing tubing from 12.75 diametre up to and including 50.8 diametre. A further three tube mills arrived in January 2014, two of which are identical to the existing machines, and the third is able to process tubing up to 76mm diametre. Both Austenitic and ferritic steels from 1mm to 2mm thick can be accommodated.

Stainless Accessories also produces perforated tubing. This tubing is manufactured by processing coil through the blanking line and punching holes in different configurations and patterns as per the customer requirements. The coil is then transferred to the tube mills and processed into perforated tubing as per the process of regular tubing.

A finishing process for full-length mirror finishes up to 6,1 metres, has recently been designed, built and commissioned by the company.

Currently all mirror polished automated tubing in South Africa is imported. Stainless Design will now be the only company in South Africa offering locally produced mirror automated tubing manufactured from locally manufactured SS coil purchased from Columbus Stainless Steel.

Toolroom equipmentEven though the Stainless Accessories company accounts for 90% of production, Mao-Cheia believes in building up the Stainless Design side. One way of doing this is by developing new products and concepts, as well as manufacturing most of the components in house, that are required for the manufacture of the modular balustrading system.

"We have always had a toolroom to maintain our dies and fixtures for the blanking presses and tube mills. Since the development of the modular balustrading system we realised that we would have to develop our toolroom further because there are many different components that make up the system."

"We like to manufacture most of these components in-house so as to control costs, while at the same time keeping any of our developments under wraps. We either machine from solid, buy in investment castings that are then further processed, or cut and machine to size. All of this is done for our own consumption and we do not look for outside work on the machining side, except if we have a special request from one of our existing clients."

The company manufactures and maintains its own dies

Some of the team at Stainless Accessories / Stainless Design from left to right Fredrick Basson, Jose Mao-Cheia, Faisal Lagardien, Carlo Dashwood, Craig Sauls and George van Wyk

Different components manufactured by the company

Installed last year was a C-Tek CNC milling machine, a C-Tek spark-eroding machine and an Akira-Seiki Performa V5.5 CNC machining centre, all supplied by MJH Machine Tools through their agent in Port Elizabeth Wam Engineering.

The latest acquisition, installed earlier this year, is a Samsung Machine ToolsPL2000SY CNC turning center which has a maximum turning diametre of 360mm, turning length of 520mm, a Y-axis travel of ±50mm and bar-work capacity of Ø65mm. The machine has a subspindle and driven tools with through tool coolant.

Additionally the company has purchased the SprutCam software to run the machining section.

"You can see from the equipment in the toolroom that we do not have a long run production setup but we can do small production runs, which are required for some of our components. We have a mix of machines that suit us and where necessary we can also machine the various plastic components that we employ in our balustrading system. Most of these components are outsourced, and again we are constantly developing new and efficient designs in this area."

"The mix of machines also allows us versatility and the ability to carry out our own development."

Overall the two companies employ 250 staff and occupy 5 500m² of space in Struandale, Port Elizabeth.

For further details contact Stainless Accessories / Stainless Design on TEL: 041 452 3529 or visit www.stailesssteelbalustrades.net