Durable, dependable, and incredibly versatile, Mentis Expanded Metal continues to be an economical and cost-effective material. The manufacturing process ensures optimum material integrity and strength and allows it to be used for a wide range of applications.

Ruben Roach, COO of Mentis Africa, one of the country’s foremost engineering and manufacturing companies based in Elandsfontein, explains that the material is made by slitting and expanding a solid sheet of metal into a web of diamonds.

“The metal sheet can, in fact, be expanded up to ten times its original size, losing no material in the process and resulting in a remarkably light mesh,” he says. “And expanded metal offers flexibility because it is available in a variety of sizes and materials.”

One of the most important features of expanded metal is its inherent structural integrity and strength. Roach says this, facilitated by the network of rigid strands, also permits light and air to pass freely through it. The final product is also lighter per metre and stronger per kg than its original sheet.

High quality local mild steel is used in the manufacturing process, but any other ductile metal such as aluminium and stainless steels are also suitable. The finished product can be painted, stove-enamelled, plated, and galvanised. The company produces expanded metal with a raised mesh, known as Mentex, and with a flattened surface, known as Flatex. Roach says that the most appropriate type of expanded metal differs for each intended application for which the material will be used. Expanded metal even provides opportunities for innovative architectural designs.

The range of mesh sizes and thicknesses of both Mentex and Flatex is extensive and the expanded metal can be bent, shaped to radii, angled, or notched. Customers can select a broad spectrum of mesh sizes, from the smallest mini-meshes with openings of 2 mm by 4 mm and a thickness of 0,4 millimetres to the larger versions with openings of 75 mm by 200 mm and a thickness of 6 mm.


In this tough economic climate purchasing decisions are, in many cases, based on price alone. This is of major concern as individuals with little understanding of the technical aspects behind a product such as handrailing can unwittingly compromise the safety of people.

Dean Weil, operations executive of Mentis Africa, cautions those making this type of purchasing decision to carefully review its selection of handrailing more thoroughly.

“Cheaper handrailing invariably means that thinner material is being used,” Weil says. “This could have a serious impact on the safety of personnel working on the plants where the product is installed. Thinner material being used in handrail manufacture obviously impacts on its structural integrity and will affect its strength over the long term.”

“In the event that the sub-standard product fails, the consequences to the company concerned could be much higher than the original savings it managed to achieve,” he says. “It makes good business sense to buy products of the correct quality, with sound structural integrity, that will contribute towards a safe working environment.”

The quality of handrailing systems in South Africa is governed by an industry standard arrived at by independent authorities, based on numerous tests to determine the correct material and specifications that ensure handrail is able to withstand a certain level of pressure and force. This includes the stanchions or uprights, as well as the horizontal rails.

The standard accepted base plate in local industry for a stanchion or upright is, for example, 10 mm thick, in order to deliver the appropriate load-bearing support for the stanchion and meet all safety requirements.

“Bases are being made available to the market that are only 8 mm thick,” Weil says. “Someone without sufficient technical knowledge could easily assume that a difference of just 2 mm cannot make a significant difference to the integrity of the product. Yet tests have proved that a 10 mm base is almost twice as strong as an 8 mm base.”

According to the industry standard, the bottom tube of the stanchion should have a wall thickness of 2.5 mm. Weil says the same applies here — inferior products with wall thicknesses of 2 mm and 1.6 mm are currently being put into use. Again, tubes with the specified 2.5 mm wall thickness have been tested and shown to be at least 20% stronger than the 2 mm and 1.6 mm tubes. The top tube should also have a minimum 2 mm wall thickness, but inferior products with a wall thickness of 1.6 mm are presently being utilised.

Handrails for industrial and general purposes should normally be of the two-rail type — comprising a handrail and a knee rail, supported on standards placed at suitable intervals. Handrailing should preferably, and always in areas where there are stairs, be continuous and have no obstruction on, above or near to it that could obstruct people’s hands as they move along it.

The recommended clearance between a handrail and any wall or object behind or below it is 65 mm.

Mentis Africa is the leading local manufacturer of high quality grating, expanded metal and handrailing systems in South Africa. With a legacy that goes back more than 70 years, today the company operates a comprehensively equipped facility in Johannesburg which is ISO accredited.


Mentis Africa supplied positive-grip, pressed-section planks and walkways from its well-known Die-Line range for the Chamber of Mines rescue drilling unit based at Colliery Training College (CTC) at eMalahleni in Mpumalanga.

The walkway’s non-slip features, combined with its high strength to weight ratio, made it ideal for the vehicle-mounted drilling unit, according to Rene Lombard, external sales representative at Mentis Africa. The walkways and planks have been installed all around the drill vehicle to facilitate easy movement of personnel. 

“Its positive serration ensures good traction even in muddy and wet conditions, enhancing the safety and efficiency of people working on the drill during a mine rescue mission,” says Lombard. “Significantly, Mentis Die-Line walkways are lightweight so while being very strong, adds little extra weight to the vehicle.”

The rescue drill is on 24-hour standby to be deployed, with the assistance of CTC staff, in the case of mine accidents. It can drill a 150 mm diameter hole into the underground area where an accident has occurred. This allows the area to be assessed by camera, and for food and water to be supplied. It is also capable of drilling a large-diameter hole of 635 mm in diameter, down which a capsule is lowered to bring trapped mineworkers to surface.

“The Mentis Die-Line products are simple to install, requiring no specialised tools and minimal welding or clipping to supports,” Lombard says. “All the necessary bolts, nuts, washers, fishplates, jointing channels, saddle clamps, splice plates and mesh clips are provided.”

Lombard notes that the Mentis Die-Line walkway sections – plants with 2 mm thickness and walkways sections with a 2,5 mm thickness, can be provided in either 500 mm or 750 mm widths at a standard length of 2.4 m.

“Where the walkway or panel is subject to a corrosive environment – like harsh chemicals or saltwater – the mild steel construction can be bitumen-dipped or galvanised,” she says. “This allows these versatile products to be used in a wide variety of applications.”


Excellent non-slip characteristics is only one of the advantages the Mentis Die-Line range of positive grip pressed section walkway product offers users.

Available in three forms, namely planks, mats and walkways, this locally manufactured walkway pressed section has a positive serration which ensures positive traction in all walking and working surfaces, even where mud, water, grease oil and detergents are present and could cause slippery or hazardous underfoot conditions. The serration on the grating applies irrespective of the direction in which a person is walking.

Lance Quinlan, national technical sales consultant at Andrew Mentis, explains that Die-Line is easy to handle and erect with minimal welding or clipping required. This reduces the need for specialised installation labour.

“Another important advantage that Die-Line offers is its high strength to weight ratio as this ensures an optimum loading bearing capacity and therefore the safety of all who use the walkway system,” Quinlan says.

The Die-Line range also ensures high light penetration for further safety benefits and the sections align perfectly for enhanced aesthetics. The sections are designed for longitudinal span, obviating unnecessary steel support and heavy kick plates, both factors contributing greatly to enhanced cost effectiveness.

Transverse loading is transferred to the integrated kick flats (toe boards) which are provided with two slotted holes at each end and positioned around the neutral axis. Pressed angle splice plates fit on the outside and into the returned top edges, and M10 bolts and nuts are provided for easy installation.

The Die-Line products, together with all the necessary accessories including bolts, washers, nuts, fish plates, jointing channels, saddle clamps, splice plates and mesh clips, can be used for work platforms, catwalks, conveyor walkways, and stair treads.

Die-Line flooring channels are available in three sizes; 150 by 2 400 mm, 250 by 2 400 mm and 305 by 2 400 mm. All are 2 mm thick. Die-Line walkway sections are available either 500 mm or 750 mm wide at a standard length of 2 400 mm and 2.5 mm thick. It can be supplied uncoated, bitumen dipped or galvanised, facilitating use in a wide variety of applications including where harsh chemicals or saltwater is present. Mats are available either 500 mm or 750 mm by 2 400mm long and 2,5 mm thick.

Apart from the obvious safety considerations, Andrew Mentis is able to provide customised solutions for specific customer requirements across a number of market sectors.


The increasing amount of inferior expanded metal products being offered on the South African market is raising concerns about the reliability of these products when they are installed in safety-critical applications.

Expanded metal meshes are produced by cold-stretching and flattening solid sheets. No material is lost during the manufacturing process, even though the original sheet of metal can be expanded by up to ten times its original size, resulting in a mesh that is considerably lighter than the equivalent area of steel plate.

Raising the reason behind the concern, Lance Quinlan, national technical sales consultant at Andrew Mentis, says that while expanded mesh can never unravel, when the metal is over-expanded the strands become narrower, the spaces between strands increases and the strength of the knuckle centres in the mesh is diminished.

“Expanded metal is a very versatile product with literally thousands of applications. In many of these functions the strength of the mesh is not a predominant issue — for instance, general racking, trays, shelves, architectural decoration, outdoor furniture and certain enclosures and partitions.

“However, where expanded metal is being used for worker safety applications such as walkways and catwalks, guardrails and protection cages, filter and machine motor covers, lift side walls and ladder rungs, a structural failure resulting from sudden impact or subtle degradation could have catastrophic consequences.,” he explains.

With inferior expanded metal, personnel are exposed to potential injury and if pieces of damaged mesh are sucked into machinery the damage, downtime and associated costs would be significant.

Quinlan says that the main reason for over-expanding metal is to save costs, but this renders the product sub-standard.

“The industry needs to be aware of this when making a purchase decision based on price alone and must always ensure that the product is fit for the purpose intended,” he continues. “Often a close visual inspection will determine if there are any cracks between the knuckles and if the strands appear too thin.”

The SABS standard 190: Part 1 – 1983 specifies the required dimensions for expanded metal products, but Quinlan says not all manufacturers comply.

Andrew Mentis regularly submits expanded metal samples to the SABS and its manufacturing facility is audited to maintain current certification verifying that these products meet the criteria for shortway, thickness and bendability.

Andrew Mentis, an ISO 9001 certified operation, has been a longstanding supplier of expanded metal products to major operators in the mining, petrochemical and power sectors.

With extensive experience in the various applications of expanded metal, Andrew Mentis manufactures Mentex® raised and Flatex® flattened meshes. Typically, both Mentex® and Flatex® are manufactured from high quality local mild steel, but can also be manufactured from any other ductile metal. The product is typically supplied unpainted, but readily lends itself to any of the normal finishing processes such as painting, stove enamelling, plating and galvanising.

These products are available in a comprehensive range of sizes, mesh sizes and thicknesses and can be fabricated in any form. The mesh can be bent, shaped to radii, angled or notched, while maintaining its inherent rigidity. It is also available in various sizes, from mini meshes, with small openings of 1.4 mm by 2 mm and with a thickness of 0.4 mm to larger meshes with 115 mm by 300 mm openings and a thickness of 6 mm.


As South Africa looks to revitalise its manufacturing sector in the ongoing quest to create decent jobs, it could take more than a few salutary lessons from home-grown market leader Andrew Mentis (Pty) Ltd, trading as Mentis Sales.

Now the leading supplier of steel grating on the African continent, Andrew Mentis was started modestly as a precision engineering works in 1950 by the man after whom the company was named. With its founder’s ingenuity and tireless pursuit of quality, the business grew even beyond the country’s borders, and now has a significant footprint in Australia and New Zealand.

“Our recipe for success today continues to build on the philosophy of our founder, which includes specialised engineering expertise, innovation, high-quality products and constant investment in the latest technologies,” says Lance Quinlan, national technical sales consultant at Andrew Mentis.

The company’s unique Rectagrid grating, which it began manufacturing in 1967, remains the leading grating in South Africa, despite other manufacturers now replicating the design. As early as the 1970s, the company invested R1 million in specialised Austrian-built equipment to achieve the quality it sought – giving the business the world’s most modern fusion-welding equipment for grating.

“Now more than ever, South African manufacturers need to compete on the global stage, so we need entrepreneurs to follow in the footsteps of our founder Andrew Mentis, who can harness the combined power of skills and technology,” says Quinlan. “This needs to be a national focus in the country’s efforts to keep local manufacturing vibrant and create jobs in which people can grow their skill-levels.”

At its 55,000 m2 premises Elandsfontein, Johannesburg, the company walks this talk – employing over 300 people at the most modern grating manufacturing facilities in the southern hemisphere. Beyond its steel and fibreglass floor grating, it makes a wide range of expanded metal building products and meshes. This includes Interlink tubular, solid and angle iron hand-railing; Die-Line Safety walkways; Mentrail and EasyRail Highway Guardrail systems; Steel Floor tiles; and Hexmesh.

“By pioneering our own grating and expanded metal products, we have developed a substantial database of intellectual property and applications experience,” he says. “This ensures that the value we create is embedded in the South African economy, so we are self-reliant in terms of design.”


Mentis Rectgrid RS40 (40/40) has long been the structural integrity champion of locally manufactured floor gratings. As the single largest producer of floor grating in Africa, Andrew Mentis understands the critical role that the load bearing capacity of this product plays in ensuring a safe working environment for personnel.

Mentis Rectagrid RS40 (40/40) floor grating has been manufactured and used by both South African and international companies for more than 65 years. This highly engineered floor grating product, produced at Andrew Mentis’ world class facility at Elandsfontein, Johannesburg, is manufactured using a pressure locking system pioneered by the company.

Quality control during the manufacturing process ensures that close tolerances are maintained and this is significant as these tolerances and standards have been adopted for use by most leading grating manufacturers worldwide.

The production process ensures that the round transverse bar fits tightly through the pierced bearer bar. This not only guarantees the superior structural integrity of the product, but also eliminates vulnerability to corrosion. To further ensure optimum reliability in corrosive environments, floor grating can be hot dip galvanised or manufactured in stainless steel or 3CR12

All transverse bars are 7.6 mm in diameter and all panels finish on half pitches in both directions with allowance for 4 mm clearance between panels, known as the Open End System. Saddle clamps automatically hold panels at full pitching space when installed.

Floor grating is used in a wide variety of applications including access walkways on process plants and in factories and manufacturing facilities.


With almost 70 years of experience in the manufacture of expanded metal products, Andrew Mentis has been supplying a growing range of applications using this high quality and versatile material.

From screens, grates, scaffolding and truck bodies to walkways, tunnel linings and garden furniture, the uses are many and varied. Much of the attraction lies in the inherent structural integrity of expanded metal, as the strength is not compromised during the manufacturing process. Another great advantage is that light and air can easily pass through, creating opportunities for various innovative applications.

While the mesh is considerably lighter than the equivalent area of steel plate – as the original sheet can be expanded up to ten times – the network of rigid strands adds strength. It is either produced as raised mesh called Mentex®, or as a flattened mesh known as Flatex®. Normally manufactured from high quality local mild steel, both the Mentex® and Flatex® can also be manufactured from any other ductile metal.

These are available in a range of thicknesses and mesh sizes. ‘Mini meshes’ have openings as small as 1,4 mm by 2 mm and a thickness of 0,4 mm, while larger meshes have openings up to 115 mm by 300 mm openings and a thickness of 6 mm. While expanded metal is normally supplied unpainted, it can be finished with painting, stove enamelling, plating or galvanising.

Lance Quinlan, national technical sales consultant at Andrew Mentis, says the application of expanded metal is really limited only by the imagination of the designer or engineer, and the material is widely used in sectors as diverse as mining, construction and food. Expanded metal has even been used in the building of grain silos, and for decorative purposes.

Among the range of Andrew Mentis building products and architectural expanded metal products already widely used in the marketplace is the Mentis Angle Bead. This product provides a true straight-edge for forming an arris – or sharp edge – in plasterwork, which resists chipping or cracking. The Mentex Expanded Riblath is an effective plaster base for walls and ceilings and permanent shuttering for concrete, while the Mentis Plaster Stop delivers a straight-edge and finish for plaster at all openings and abutments.

Also in the range is Mentlath 213, used to provide a key for plaster and as a reinforcement to minimise cracking, as well as Mentex Strip Mesh 210, for plaster reinforcing along lines of potential weakness – such as at the corners of doors and window frames. Brickforce is for reinforcing in brickwork to strengthen walls, and Mentex 188/99 hailguards prevent gutters from filling up with hail, dirt and leaves.


Statistics have shown that the frequency of high speed accidents has grown exponentially on South Africa’s major routes, and injuries could be far worse were it not for the robust Mentrail guardrails that are erected on most Gauteng highways and on countless other arterial routes in South Africa.

Mentrail guardrails are manufactured by Andrew Mentis, and these guardrails are designed to ensure that out-of-control vehicles are restrained in such a manner that the least damage and danger are caused to other vehicles on the road.

Specialised machinery at Andrew Mentis’ facility in Elandsfontein manufactures the 2.6 mm thick steel guardrail in standard 3.81 metre lengths to SANS 1350-2005 specifications. The Mentrail guardrail has a tensile strength of 445 MPa and yield strength of 310 MPa.

Adding to the practicality of the Mentrail system, if a section of the guardrail itself is damaged, the performance of undamaged portions remains unaffected.

Mentrail is easy to install without further tension or stretching, and this can be done by a small team without requiring any special tools.

The advantages of Mentrail’s prefabricated, bolt-together, assembly-on-site design are obvious, with all assembly hardware supplied, eliminating any need for field fabrication. Pre-punched holes further facilitate erection, using 350 mm long post bolts to fix it to upright wooden posts. Available in either galvanised or uncoated lengths, it has a buried end for the start and terminates in an end wing.

For instances where double rows of guardrails are used, it has bullnose end wings. Its performance is enhanced by joints which absorb normal expansion and contraction so that the posts remain in alignment. Concave and convex rails are also available to cater for bends and turns.


Liability claims from slips, trips and falls in the workplace can be financially debilitating and have an extremely negative impact on the reputation of a business. Considered the most frequent cause of injuries in the workplace, these incidents can result in serious downtime and even closure of facilities.

Floors, stairs and handrails are often cited as the cause of such accidents. In some incidents, injury is caused by factors beyond the reasonable control of the business owner. However, there is great wisdom in the adage ‘prevention is better than cure’.

Lance Quinlan, national technical sales consultant at Andrew Mentis, says that companies should consult floor grating specialists to ensure that their floor grating adheres to the required building regulations and occupational health and safety (OHS) standards.

He explains that unfortunately for the consumer, not all floor grating products on the market are of a suitably high standard. “An inferior quality product may well look identical to a reputed brand when viewed through the eyes of an unsuspecting customer. However, the real litmus test comes after the installation is completed and employees start walking on the floor grating.”

Quinlan cautions that customers should carefully research the claims made by the floor grating manufacturer. “Mentis floor grating is engineered to take specific loading which then ensures the optimum safety of the people walking on or working in those areas. We initially meet with customers to determine their exact needs, then our processing department compiles the layouts for the required products according to the structural steel drawings supplied by the customer. A complete understanding of the load bearing capacity of grating is required to ensure that the correct floor grating product is selected for an application.”

All Mentis floor grating is manufactured in a world class facility at Elandsfontein, Johannesburg using a pressure locking system pioneered by the company. “Quality control is stringent during the manufacturing process to ensure that close tolerances are maintained and that the round transversal bar fits tightly through the pierced bearer bar on our floor grating products,” he says.

Mentis has two predominant floor grating products – Rectagrid RS40 40/40 and Rectagrid RS80 80/40. RS40 40/40 is a premium brand and is formed through a process of compressive pressure locking of bearer bars and transversals to form an exact pitch of 40 mm by 40 mm. Rectagrid RS80 80/40 is identical to RS40 40/40 grating except that we omit every second bearer bar, giving an 80 mm pitch bearer bar with a 40 mm pitch transversal. This effectively reduces the RS80 80/40’s permissible load bearing capacity by 50%.

Quinlan emphasises that the most critical element is the load bearing capacity of the floor grating. “The best way to ensure the structural integrity of floor grating is to align yourself with a manufacturer who has designed and engineered the product to attain predetermined tolerances. Mentis is pedantic about the strict criteria set for its floor grating.”

Non-negotiable factors include the fact that the transversals must be positively and permanently locked to the bearer bars. “In addition, there must be no cracks or crevices at intersections which could harbour corrosion. The locking method at the intersections should be designed to use the full depth of the bearer bar when calculating loads. Finally, the grating panels should be flat, square and untwisted. Safety in the workplace simply cannot be compromised,” he concludes.