B.E.D.: Switching from acetylene to alternative fuels for cutting, brazing, soldering and heating
ACROSS South African industries from mining and manufacturing to agriculture and energy, acetylene remains the default fuel choice for cutting, brazing, soldering and heating. Yet the case for switching to alternative fuels, such as liquefied petroleum gas (LPG), propane and MAPP (Methylacetylene-Propadiene Propane) gas, is growing stronger. Bolt and Engineering Distributors Group (B.E.D.), through its appointment as an authorised distributor for the international Harris Products Group, is helping South African industry to make this transition with confidence.
According to Shaun Geyer, B.E.D.’s Harris Products Brand Ambassador and Technical Specialist, the barrier to change is rarely cost or performance, but awareness: “It is surprising that acetylene remains as widely used as it is in South Africa, given the clear safety, cost and performance advantages of alternative fuels. The transition is simpler than may be assumed, and the benefits are compelling.”
A complete, optimised system
Central to the switch is the Harris injector mixer, which addresses a fundamental challenge: oxygen and LPG do not blend naturally.
“The injector mixer increases oxygen velocity through the torch, creating turbulence which produces a far more homogeneous mixture, resulting in better flame and cut quality,” explains Geyer. “What drives cutting performance is not flame temperature alone, but how effectively heat transfers into the material being cut.”
Harris’s high-preheat and high-speed alternative fuel nozzles maximise this effect. The injector also draws fuel gas through the system at very low pressure, under two PSIG (Pounds Per Square Inch Gauge) – reducing fuel consumption while almost completely eliminating flashback risk, delivering both a safety and a cost benefit.
Anthony McGuiness, Sales Manager for the Harris Products Group in Sub-Saharan Africa, points to the company’s long history of innovation in this space: “Harris pioneered alternative fuel cutting in the late 1930s and early 1940s with the Model 62-5F injector torch, which is still in use today – a testimony to its quality and longevity.”
“The transition from acetylene requires changing just three components: the gas-specific regulator, the hose and the nozzle, with the flashback arrestor remaining the same.”
For manual cutting, alternative fuels are superior from 15 millimetres steel plate thickness upwards, producing a clean, carbon-free cutting edge that eliminates the costly grinding step required after acetylene cutting and before welding. Cutting with alternative fuels also requires less operator skill, as the material is very close to the torch, with a nozzle-to-plate distance of only 10 to 15 millimetres.
For oxyfuel cutting, LPG covers 90 to 95 percent of applications and is the standard recommendation, being both widely available and cost-effective. For brazing, at 650 to 900 degrees Celsius and soldering, at around 350 degrees Celsius, customers may use MAPP gas or propane with a trigger torch, which draws in atmospheric oxygen. For industrial heating, LPG is again the appropriate choice.
Importantly, welding cannot be done with alternative fuels, as they lack the carbon content which acetylene has, which is essential for weld pool development.
McGuiness confirms that Harris addresses safety risks through product design, and all products meet international safety standards, including the emerging EN 17931 standard. Locally, B.E.D. ensures customers receive the correct gas-specific equipment, together with hands-on technical guidance on how to use it safely.
“We are focused on supporting our customers through every step of the process to using alternative fuels for cutting, brazing, soldering and heating.
This will be achieved through B.E.D.’s extensive national branch network and distribution centre as well as our substantial regional sales team, logistics infrastructure, excellent longstanding customer relationships and technical credibility,” Geyer concludes.
