Platework Fabrication in Mining: Tanks, Chutes, and Ducting Excellence

Platework fabrication is the backbone of many mining infrastructure components, including storage tanks, ore chutes, bins, and large ducting systems. These heavy-duty steel plate structures must withstand harsh conditions and demanding loads. In South Africa and across the African continent, excellence in platework fabrication is critical to ensure reliability in mining operations. This blog explores the role of platework in mining, highlights standards and quality practices (like API 650, ISO 3834, SANS 347), and examines case studies demonstrating the advantages of modular, prefabricated platework in the African mining context.

The Role of Platework in Mining Infrastructure

Mining operations rely on robust platework for storage and processing needs. Thickener tanks, leach tanks, and silos store vast quantities of slurry or liquids, while chutes and bins handle the constant impact of ore and aggregates. Similarly, ducting systems channel dust or exhaust gases in processing plants. All these structures are fabricated from steel plate (often carbon steel or alloy steel) cut and welded into the required forms. Platework must be engineered to handle abrasion, corrosion, and heavy loads typical in mining environments. For example, a large dewatering thickener tank can span tens of meters in diameter and hold thousands of tonnes of material – requiring precision engineering and high-quality welding to ensure structural integrity. Even ore chutes and bins must be built to endure constant wear from falling rock and ore.

Because these components are so critical, mining companies demand “high-spec platework” – meaning structures fabricated to the highest quality standards and tight tolerances. Any failure (like a tank rupture or chute collapse) could halt production or pose safety hazards. Thus, platework fabrication is not just heavy steelwork; it’s a high-precision discipline within mining engineering.

Adhering to International and Local Fabrication Standards

To achieve excellence in platework, fabricators adhere to stringent standards and codes. One key standard for storage tanks is API 650, developed by the American Petroleum Institute. API 650 is widely used for the design and construction of large, welded steel storage tanks at atmospheric pressure. It covers everything from materials and welding to seismic design and inspection requirements. By designing mining tanks (such as water or reagent storage tanks) to API 650, engineers ensure features like proper anchoring, allowance for internal pressures, and rigorous testing of welds, resulting in tanks that meet global safety benchmarks.

Equally important is the quality of welding fabrication, governed by standards like ISO 3834. ISO 3834 specifies quality requirements for fusion welding of metallic materials, essentially laying out a welding quality management system. In South Africa, ISO 3834 certification has become common among leading fabricators to assure clients of consistent welding excellence. This standard mandates controls on welding procedures, welder qualifications, materials handling, and non-destructive testing (NDT). The goal is to **“build in” quality during fabrication rather than trying to inspect defects out after the fact. For instance, Betterect, a renowned South African steel fabricator, notes that “We fabricate according to ISO 3834, which specifies the production control requirements for fusion-welded products globally”. By doing so, every stage of welding – from preparation to execution and inspection – follows a controlled process, reducing the risk of weak welds or failures.

When platework involves pressure vessels or pressurised systems, compliance with local regulations is vital. South Africa’s SANS 347 (Categorisation and conformity assessment criteria for all pressure equipment) works in tandem with the national Pressure Equipment Regulations (PER). SANS 347 classifies pressure equipment by risk category and mandates certain quality standards. Legally, in South Africa any pressure equipment (including certain tanks or pressurised ducting) operating above 0.5 bar gauge must comply with SANS 347 and the PER. The PER explicitly requires that such equipment be fabricated under an ISO 3834-2 certified quality system. In practice, this means a platework fabricator building, say, a pressurised process tank or steam duct must have certified welding procedures and quality controls equivalent to ISO 3834 Part 2 (comprehensive quality requirements). This integration of SANS 347 and ISO 3834 ensures that pressure-bearing platework in mining is built to the highest safety standards to prevent catastrophic failures.

Other standards often come into play as well. For example, SANS 10160 (structural loading code) might be used to design platework for wind or seismic loads, and SANS 347 references international vessel codes like ASME VIII for pressure vessel design. Moreover, ISO 9001 quality management certification is common among fabricators, ensuring overall project management and traceability in fabrication projects. Together, these standards create a framework in which African mining projects can trust the platework supplied will meet both international norms and local regulatory requirements.

Case Study: Modular Thickener Tanks in Southern Africa

One shining example of platework excellence is the collaboration between Betterect and FLSmidth to deliver several oversized bolted thickener tanks for a mining project in Southern Africa. FLSmidth, a global mining equipment supplier, contracted Betterect to fabricate multiple 45m diameter dewatering thickeners – each essentially a giant steel tank for settling slurry. The project demanded absolute precision: these tanks consist of hundreds of tons of platework, requiring over 60 km of welds in total fabrication.

Betterect employed a modular fabrication approach. The thickener tanks were built in large sections at the fabrication facility in Johannesburg, rather than welding the entire tank on the mine site. Each module was engineered with flanged connections so that the segments could be bolted together on-site with perfect alignment. This approach brought multiple benefits:

Speed: Fabricating the tank sections in parallel and in a controlled workshop environment allowed Betterect to complete the huge thickeners in less than half the usual time. In fact, what normally might take 16–20 weeks was done in record time.
Accuracy: Achieving alignment tolerances of 1 mm over 25 m span was possible with precision jigs and advanced welding techniques in the shop. Such accuracy ensured that when bolted together, the segments fit “with mathematical precision” – critical for structural stability.
Quality Control: All welding was done under ISO 3834 conditions with 100% NDT of each weld by third-party inspectors. Betterect even invested in advanced pulse-arc welding technology to improve weld quality and productivity. As Managing Director Nicolette Skjoldhammer noted, pulse welding “reduces defects… resulting in excellent weld quality… while significantly reducing welding time”. The result was welds of exceptional integrity, verified by radiographic and ultrasonic testing.
Simpler Assembly: On site, the bolted design meant no field welding was needed. No “hot work” on site improved safety and removed the need for large skilled welding crews at a remote mine. Smaller crews bolted the thickener segments together in about three weeks, far faster than traditional site-welding would take.
Cost Savings: The faster installation and reduced skilled labor translated to roughly 30% overall project cost savings compared to a conventional welded tank project. These savings come from shorter project schedule, less on-site manpower, and avoiding rework (since modules were pre-fitted and inspected).

This case study underscores how modular, prefabricated platework can achieve world-class results in Africa. By blending local fabrication expertise (Betterect) with global engineering (FLSmidth’s design) – a model dubbed “Team Africa” – the project delivered high-spec equipment on time. The thickeners meet the strictest quality criteria and will operate in a “demanding environment” with confidence in their longevity. Notably, Betterect’s standard practice of full NDT on every weld and adherence to ISO 3834 gave FLSmidth the confidence to deploy these giant tanks, knowing they comply with the highest design codes and quality standards.

Advantages of Modular and Prefabricated Platework

The success of the above project highlights a broader trend: the advantages of shop-fabricated, modular platework in mining and infrastructure. Some key advantages include:

Improved Quality: Workshop fabrication allows better control over welding and assembly. Climate-controlled facilities and fixed jigs ensure each plate and weld is done to spec. As seen, each weld can even be inspected and fixed before leaving the shop. This is far superior to trying to accomplish the same quality with cranes and welders outdoors at a remote site. In summary, workshop = higher quality, less rework.
Faster Project Schedules: By breaking a large structure into modules, different teams can work in parallel on each module, compressing the fabrication schedule. Site installation then becomes a matter of assembly, which is much faster than building from scratch on site. Studies have shown that fabrication and installation times are much shorter with pre-made spools or modules than on-site construction. In mining projects where time is money, shaving weeks or months off construction can yield significant savings.
Cost Savings: Shorter construction duration and fewer specialised labor requirements on site lead to lower costs. Additionally, labor productivity in a factory is higher (no weather delays, better equipment, easy access to tools). Modular platework also reduces on-site labor camps and logistics costs, since fewer workers are needed at the mine. All these factors can reduce total installed cost. Decision-makers often note that prefabrication cuts labor costs and avoids costly on-site mistakes.
Safety: Working at ground level in a workshop is inherently safer than doing high-elevation welding and erection on site. By doing as much as possible in controlled conditions, site safety risks (falls, welding fumes in confined spaces, etc.) are minimised. Also, eliminating on-site welding (as with bolted tanks) avoids fire hazards. The Betterect thickener project, for example, benefited from “no hot work required on site, and a much safer assembly process”.
Logistics to Remote Sites: Many African mining projects are in remote areas with limited infrastructure. Prefabricated platework can be designed in shippable modules that fit on trucks or containers. This way, the heavy processing equipment can be mostly built in urban centers (where fabrication facilities exist) and then transported in pieces to site. It is often easier to ship many small loads than to bring in an army of skilled welders and tons of steel to fabricate on site in a jungle or desert. Modular design accounts for transportation limits (e.g., bolted sections sized for road transport).
Quality Standards Compliance: Prefabrication also makes it easier to ensure compliance with standards. For instance, all welding can be done under an ISO 3834 certified process; all materials can be verified against project specs (mill certificates, etc.) before assembly. By contrast, field fabrication in remote areas might tempt shortcuts. Delivering a finished module with all documentation (weld maps, NDT reports, material traceability) gives the mine a higher assurance that, say, their acid storage tank truly meets API 650 and SANS 347 requirements as claimed.

Growing Demand for High-Spec Platework in Mining

With mining companies across Africa striving for greater efficiency and safety, the demand for high-spec platework fabrication is on the rise. Several factors drive this trend:

Expansion of Mining Projects: African mining is growing in regions like West Africa (gold), Southern Africa (platinum, diamonds), East Africa, and beyond. New projects mean new processing plants, tanks, and conveying systems – all requiring quality platework. Even existing mines are investing in infrastructure upgrades (for example, adding new concentrators or tailings thickeners) which calls for specialist fabricators.
Focus on Reliability and Downtime Reduction: Unplanned downtime is extremely costly. Using well-fabricated platework that meets top standards reduces the risk of breakdowns. Mining firms are willing to invest in “excellence” upfront to avoid failures later. For instance, a mine that installs an API 650-compliant tank with proper corrosion allowances and weld quality can trust it for decades of service, whereas a cheaply built tank might leak or fail early.
Local Fabrication Capacity: African fabrication companies have matured, achieving certifications like ISO 3834 and ISO 9001, and handling mega-projects. In South Africa alone, nearly 288 companies are ISO 3834 certified as of 2023, a number that has grown steadily. This means mining companies have local partners capable of delivering world-class platework. The Betterect example shows a local fabricator meeting global OEM specs in record time, which will encourage similar collaborations.
Modular Construction Trends: As demonstrated in other industries, modular construction is gaining favor for its efficiency. We see this extending to mining – from modular thickener tanks to even entire modular process plants. The success of bolted thickeners and prefabricated plants (some EPCM companies offer “plant in a box” solutions) is fueling wider adoption. Clients are asking for designs that allow shop fabrication and quick site assembly to de-risk project delivery.
Stringent Compliance and ESG Goals: Regulatory pressure (like South Africa’s safety standards SANS 347) and corporate ESG (environmental, social, governance) commitments mean mining firms can’t cut corners on infrastructure. They must use certified materials, qualified welders, and prove compliance. High-quality platework fabrication aligns with these goals – for example, ensuring tailings tanks don’t collapse and pollute, or ensuring worker safety by using certified tanks and chutes. Thus, investment in proper fabrication is seen as part of responsible mining practice.
Statistics & Market Trends: While specific platework market data is niche, related indicators show positive trends. Global mining capital expenditure by major companies was expected to rise over 10% in 2024, and Africa’s share of this spending is significant as several new mines come online. The fabrication and construction sector benefits proportionally. In South Africa, despite some recent dips, mining investment still accounts for a substantial portion (~14%) of fixed investment, underpinning continued demand for infrastructure. Moreover, as mineral processing technology evolves (e.g. larger thickeners, bigger crushers requiring larger chutes and bins), the complexity and size of platework also increase – calling for top-tier fabrication capabilities.

In summary, platework fabrication is a critical element of mining projects that requires a combination of engineering expertise, skilled welding, and adherence to standards. African mining operations are increasingly insisting on quality and modular construction, as evidenced by projects like the Betterect/FLSmidth thickener collaboration. By leveraging international standards (API 650, ISO 3834, etc.) and innovative modular approaches, mining projects can achieve “tanks, chutes, and ducting excellence” – resulting in safer, more efficient, and cost-effective operations.

Get in touch with S.M.E.I. Projects today to discuss your next project.