Sales of the Smoothflo gas pressure regulator, which is equipped with a piston- embedded safety valve, from gas and welding company Afrox, exceeded expectations for the first year and, subsequently, helped to accelerate global demand.

Smoothflo was launched onto the South African market in July 2013. The regulator is suitable for use in all manufacturing industries, including mining, industrial, metal processing, shipbuilding and engineering, which use acetylene and oxygen.

Afrox gas equipment business manager Devandran Naicker tells Engineering News the Smoothflo regulator has provided exposure for Afrox South Africa to overseas markets, including Australia, Canada, Sweden and the UK. It was launched onto the Australian and Swedish markets in August and onto the UK and Canadian markets earlier this month.

“Sales figures are continuing to grow, with 2 000 units being sold locally and in excess of 10 000 units internationally. The sales figures are well above our first-year target,” he adds.

In the next three years, Afrox predicts that sales figures are likely to exceed 60 000 units.

Improved Design
Afrox gas equipment product manager Lourens le Roux tells Engineering News the Smoothflo incorporates a safety valve into the construction of the regulator, which enhances the safety features of the regulator.

The reliability of the Smoothflo regulator is also enhanced, with dust intrusion into the safety valve being decreased through its embedded design. “The embedded design also leads to fewer instances of safety-valve removal or tampering by unauthorised personnel, or replacement with an inferior part,” he says.

Design work on the regulator began in early 2011, when Afrox conducted worldwide customer focus-group discussions in partnership with industrial gas and engineering company The Linde Group. The feedback from gas industry clients was used to enhance the new regulator to ideally suit the clients.

The research gathered from the focus group discussions was referred to Afrox’ research and development department, which subsequently developed several prototypes before deciding on the final version that is being manufactured at the company’s Germiston-based plant.

Le Roux says gas regulators have employed a standard design over the past 30 to 40 years, which further encouraged Afrox to pursue a newly designed gas regulator that will afford the company substantial growth in a stagnant industry.

He tells Engineering News the Smoothflo regulator started as a “greenfield project” owing to the “complete redesign of a conventional gas regulator”.

Increasing Usability
Basic conventional gas regulators employ a neoprene diaphragm to adjust gas pressure, Le Roux notes. However, neoprene diaphragms are prone to bursting when they are subjected to overpressurisation or improper opening and closing procedures.

To regulate gas pressure, Afrox designed a lever-activated piston valve, which is unaffected by overpressurisation or improper opening or closing. The safety valve is built into the piston technology.

The piston also assists in countering gas pressure drops, keeping gas pressures at consistent levels throughout use. “The Smoothflo offers multistage regulating capabilities with single- stage design,” says Le Roux.

Further, a break-off inlet stem has been designed to shut off gas flow, should the gas regulator unintentionally become detached from the gas cylinder.

One of the challenges Afrox engineers faced during the design of the Smoothflo involved the fine adjustment of gas pressure with fewer turns using the adjustment knob. This challenge was overcome through a complete redesign of adjustment springs to incorporate an accurate setting ability using fewer turns.

“Conventional gas regulators usually require about 11 turns to attain maximum pressure, whereas the Smoothflo requires only three turns to attain maximum pressure,” says Le Roux.

Smoothflo employs a maintenance-free design. However, in the event of repair work, an authorised Afrox technician should be consulted to conduct such work.

Adding to improved health and safety features is the fire-retardant cladding, which, if combusted, produces nontoxic fumes. “This feature enables us to pursue sales in underground mining operations, as the product will not compromise underground safety regulations, even in the event of a fire,” he says.