Johannesburg-headquartered grating manufacturer Andrew Mentis produces a range of corrosion-resistant floor grating as well as handrailing systems in galvanised, 304 stainless steel and 3CR12 options that are suited to the extreme conditions found in wastewater treatment plants.

Wastewater traveling through sewer lines can become anaerobic or septic as a result of the metabolic processes of microbes commonly found therein. Specific sulphate-reducing bacteria thrive in these conditions and generate hydrogen sulphide as a byproduct of their respiration.

Hydrogen sulphide can be responsible for severe corrosion problems and toxic conditions within wastewater conveyance and treatment facilities.

Mentis grating is engineered to suit situations where strength to weight ratio is important, while Mentis handrailing is designed for optimum safety.

Andrew Mentis national technical sales consultant Lance Quinlan explains that the water and wastewater industry often create a slippery environment for operators and technicians.

“Vapours, water and chemicals create slick underfoot and handhold conditions near large machinery and tanks.”

Safety is paramount in this type of environment, where weakened handrailing and floor grating, caused by corrosion and damp, can result in slips, trips or falls, he stresses.

“In addition, replacing broken or corroded handrailing or floor grating results in unnecessary downtime which can impact negatively on productivity.”

Galvanising or using stainless steel in a wastewater treatment plant is not only a safe and cost-effective option, but it does not compromise the aesthetics of the environment, states Quinlan.

The company has been producing Rectagrid RS40, 40 mm by 40 mm floor grating, for more than 40 years and the effectiveness of the product has been proven over years of application in the construction, infrastructure and mining sectors.

The Mentis Rectagrid RS40 is manufactured using a pressure-locking system pioneered by the company. The locking characteristics guarantee the structural integrity of the product and further enhance its integrity in a corrosive environment.

The transversals on the floor grating are positively and permanently locked to the bearer bars and the locking method at the intersections is designed to use the full depth of the bearer bar when calculating loads. This ensures that the load-bearing capacity is top of mind when design and manufacturing is undertaken, states Quinlan.

The company’s tubular stainless-steel handrailing is reputed for its corrosion and stain resistance qualities. The stanchion base plates are designed to allow moisture to drain from the stanchion, adding further credence to its corrosion-resistant benefits. These handrails are not only functional, but also resilient and durable, notes the company.

The tubular handrailing system is complemented by a range of standard angles and matching accessories, with different bends and end-closers adding to the versatility of the product. The stanchions are 42.9 mm in diameter and have a 2.5 mm wall thickness, and are also available in 3CR12, 304 and 316 stainless steel polished to a satin finish.

In addition to grating and industrial handrail systems, Andrew Mentis, established in 1950, offers expanded metal, Mentrail (guard-rails for roads), steel floor tiles and Mendrill (automatic drilling and boring machines).  These products can all be obtained from the company's branches in Pretoria, Cape Town and Durban.

Andrew Mentis purchased R & R Engineering, which now trades as Mentis Australia. The company also purchased Rhino Grating, operating out of Brisbane and Melbourne.