Case Study: YZH BB350 Restores Continuous Underground Ore Transfer at Malaysian Mine — Operators Work Safely from Remote Console

Project Snapshot

The Operation: Underground Ore Transfer in a Malaysian Hard Rock Mine

Malaysia's hard rock mining sector — spanning gold, copper, and base metal operations across Peninsular Malaysia and East Malaysia — operates in some of the most geologically complex underground environments in Southeast Asia. Ore bodies are often structurally variable, producing a wide range of fragment sizes when blasted. Managing the resulting oversize material through the underground ore handling system is a persistent operational challenge.

At this underground mine in Malaysia, ore drawn from active stopes was transferred via a series of ore passes and tunnel drifts to a grizzly screen station installed at a key underground transfer level. The grizzly screen served as the primary size control point in the underground ore handling chain: correctly sized material passed through to the loading pocket below, while oversize boulders were retained on the screen bars for secondary breaking before transfer.

The grizzly screen station was located within a tunnel drift — a confined, elongated underground excavation with limited working height and restricted access. The combination of confined geometry, overhead rock exposure, and the unpredictable nature of ore draw from the stopes above created a working environment that the mine's safety team classified as high-risk.

The Problem: Frequent Blockages, Dangerous Manual Clearing

Blockage Frequency and Impact

Hard rock ore from the mine's stopes regularly produced boulders exceeding 600 to 900 mm in their longest dimension — well above the grizzly screen's maximum pass size. These boulders bridged across the screen bars, accumulating rapidly and creating complete blockages that halted ore transfer from the stope level to the loading pocket below.

Blockage events occurred four to six times per 10-hour production shift. Each event stopped ore transfer completely until the blockage was cleared.

The Manual Clearing Procedure: High Risk, High Cost

The mine's existing clearing procedure required a two-person team to descend to the grizzly screen station and manually break or dislodge the bridging boulders using pneumatic handheld breakers and pry bars. The procedure involved:

• Halting ore draw from the stope above

• Issuing a confined space entry permit and safety clearance

• Two workers descending to the grizzly screen level in full PPE

• Manual breaking of the bridging boulders — typically 40 to 90 minutes per event

• Worker withdrawal, safety check, and resumption of ore draw

The hazards associated with this procedure were well documented in the mine's risk register:

• Rockfall from above: Residual ore and loose rock in the ore pass above the grizzly screen could dislodge during or after manual breaking, falling onto workers below

• Structural collapse: The confined tunnel drift geometry limited escape routes and increased the consequences of any sudden ground movement

• Dust and fume exposure: Pneumatic breaking in a confined underground space generated high dust concentrations, with limited ventilation capacity to clear the air rapidly

• Ergonomic injury: Operating a heavy handheld breaker in a confined, low-headroom space over extended periods created significant musculoskeletal risk

Despite strict permit-to-work controls, the mine had recorded two lost-time injuries related to manual grizzly clearing in the three years prior to the BB350 installation. The mine's management had committed to eliminating manual entry into the grizzly hazard zone as a priority safety objective.

Production Impact

With four to six blockage events per shift and an average manual clearing time of 40 to 90 minutes per event, the mine was losing between 3 and 9 hours of ore transfer time per shift to grizzly blockage management. Across a full operating year of 300 production days on two shifts, this represented a cumulative production loss of 1,800 to 5,400 hours — a significant proportion of the underground ore handling system's available operating time.

The downstream surface crushing circuit was operating well below its design capacity as a direct result of the interrupted underground ore supply.

The Solution: YZH BB350 with 5G Wireless Remote Control Console

Following a structured equipment evaluation process, the mine's engineering and safety teams selected the YZH BB350 pedestal rock breaker boom system, configured with a 5G wireless remote control console.

Why the BB350

The BB350 is the larger model in YZH's B Series heavy-duty range, and its specifications were a precise match for the requirements of this application.

Reach and Working Envelope

The BB350's maximum horizontal working radius of 6,000 mm and maximum vertical working radius of 3,950 mm provided full coverage of the grizzly screen from the available pedestal position within the tunnel drift. The minimum vertical working radius of 1,860 mm allowed the hammer to work at low positions within the screen without the boom fouling the tunnel roof or walls — a critical requirement given the confined drift geometry.

The maximum installed height of 3,250 mm was confirmed to be within the available headroom at the grizzly screen station, allowing the boom to be stowed safely without contact with the tunnel roof.

Structural Capacity for Hard Rock

At 3,168 kg (boom weight without hammer), the BB350 is a heavy-duty structure built for sustained operation against hard, competent ore. The mine's ore has a Uniaxial Compressive Strength (UCS) in the range of 120 to 180 MPa. The BB350's high-strength steel construction and compatibility with high-energy hydraulic hammer configurations provided the structural integrity and impact energy required for efficient breaking of large, hard boulders in this demanding application.

360° Slewing Coverage

The BB350's full 360° slewing capability ensured that the hammer could reach every point on the grizzly screen surface — including the far corners and edges where bridging events were most likely to initiate — from a single fixed pedestal position. This eliminated the need for any repositioning of the pedestal or manual intervention to reach difficult blockage locations.

Extreme Climate Adaptability

The BB350 is rated for operation in temperatures from −45°C to +75°C. While Malaysia's underground environment does not present extreme cold, the high ambient temperatures in deep underground workings — often exceeding 35°C to 40°C at the working face — were a relevant consideration. The BB350's thermal design confirmed suitability for continuous operation in the mine's underground temperature conditions.

Why 5G Wireless Remote Control

The 5G wireless remote control console was the defining feature of the solution from a safety perspective. The mine had already invested in a 5G underground network infrastructure as part of a broader digitalisation programme, and the BB350's 5G console integration allowed the rock breaker boom to be operated as a fully remote system within that existing network.

Key capabilities of the 5G remote control configuration:

• Low-latency control response: 5G network latency of under 10 milliseconds provides near-instantaneous control response, giving the operator precise, real-time control of boom positioning and hammer activation

• High-definition camera integration: The operator monitors the grizzly screen via HD cameras installed at the screen station, displayed on the remote console screen, providing clear visibility of the blockage and the hammer position without any personnel being present underground

• Flexible operator positioning: The operator can work from any location within the mine's 5G network coverage — the designated surface control room, the underground control station, or any other safe position — without being physically present at the grizzly screen station

• Operational data logging: The 5G console logs boom operating hours, hammer activation cycles, and fault events, providing maintenance teams with accurate service interval data and fault history

The combination of the BB350's structural capability and the 5G remote console's operational flexibility delivered exactly what the mine required: a system that could break hard ore boulders efficiently and reliably, operated entirely by personnel in a safe location, with no requirement for anyone to enter the grizzly hazard zone.

Installation

The BB350 was delivered to the mine site in a single 20GP container. The complete system — boom structure, pedestal column, electric hydraulic power unit, control cabinet, 5G remote console, and hydraulic hammer — was packed and shipped as a single consignment, simplifying import documentation and site receiving logistics.

Installation was completed over six days:

YZH's commissioning engineer worked alongside the mine's underground maintenance team throughout the installation, transferring technical knowledge to the mine's own personnel to ensure full in-house capability for routine maintenance and first-level fault diagnosis from day one.

Results

Safety Performance: Zero Personnel Entry Achieved

The mine's primary safety objective — eliminating all personnel entry into the grizzly screen hazard zone for routine blockage clearing — was achieved from the first day of BB350 operation.

Since commissioning, no personnel entries into the grizzly screen station have been required for routine ore breaking operations. All blockage clearing is performed remotely by the console operator. The mine's safety management system has been updated to reflect the reclassification of the grizzly clearing task from a high-risk confined space entry to a remote-controlled operation.

The two injury categories previously associated with manual grizzly clearing — rockfall struck-by and ergonomic injury from handheld breaker operation — have been eliminated from the mine's active hazard register for this task.

Productivity: Clearing Time Cut by More Than 85%

The reduction in clearing time is attributable to three factors: the elimination of the safety clearance and permit-to-work process required for manual entry; the immediate availability of the BB350 (no mobilisation time, no crew assembly); and the superior breaking efficiency of the hydraulic hammer compared to manual pneumatic breaking tools.

Downstream Impact: Surface Crusher Utilisation Improved

With underground ore transfer now operating with significantly fewer and shorter interruptions, the surface crushing circuit has seen a measurable improvement in feed consistency. The mine's processing plant manager reports that surface crusher utilisation has increased by an estimated 12 to 18 percentage points since the BB350 was commissioned, as the previously chronic interruptions to underground ore supply have been largely eliminated.

This downstream productivity improvement — which was not the primary objective of the BB350 installation — has contributed additional financial value that the mine's management had not fully anticipated at the time of the investment decision.

Financial Summary

The mine's engineering team conducted a post-installation ROI analysis based on six months of operational data. The key findings:

Note: Financial figures are estimates based on the mine's internal cost and production data. Actual results will vary by operation.

Operator and Management Feedback

"The BB350 changed how we think about this part of the operation completely. What used to be one of our most dangerous tasks — sending people into the grizzly area — is now something the operator handles from the control room in a few minutes. The safety improvement is obvious, but the production improvement surprised us. We didn't realise how much time we were losing until we saw how fast the boom clears a blockage."
— Mine Operations Manager, Malaysia

"From a maintenance perspective, the BB350 is straightforward. The YZH team trained our people well during commissioning and the system has been reliable. We do the scheduled checks and it just runs."
— Underground Maintenance Supervisor, Malaysia

Equipment Specification Summary

Key Differentiators: BB350 vs. BA300 — Choosing the Right Model

The BB350 and BA300 are both members of YZH's B Series heavy-duty range and share the same core design philosophy. The BB350 is the larger model, offering greater reach, higher structural payload, and a larger working envelope — making it the preferred choice for applications where the grizzly screen or crusher feed opening is larger, the pedestal must be positioned further from the work zone, or the ore is particularly hard and large-fragmented.

For operations where the BA300's reach is sufficient, it offers a more compact and lighter solution. For larger grizzly screens, wider tunnel drifts, or applications requiring greater standoff distance from the hazard zone, the BB350 is the appropriate choice.

See also: Case Study — YZH BA300 at Underground Mine, Laos

About YZH

YZH has been manufacturing pedestal rock breaker boom systems since 2002. With over 3,000 units installed in 60+ countries, YZH is one of the most experienced manufacturers of stationary rock breaking solutions for mining and quarrying applications globally.

The BB350 is part of YZH's B Series heavy-duty range, designed for demanding primary crushing, grizzly screen, and underground ore handling applications. All B Series systems are available with electric HPU configuration and advanced remote control options — including 5G wireless console, standard radio remote, and wired panel — to match the specific infrastructure and safety requirements of each installation.

YZH systems are exported worldwide with full CE certification, comprehensive export documentation support, and after-sales technical assistance provided directly by the YZH engineering team.

Planning a Similar Underground Installation?

If your underground mine is managing grizzly screen blockages in a tunnel drift or ore pass station with manual labour, the YZH BB350 — or another model from the B Series range — may be the solution you need.

Provide our engineering team with your tunnel drift dimensions, grizzly screen size, ore type and fragment size, available headroom, and remote control infrastructure details. We will recommend the correct system configuration and provide a detailed quotation.

Phone / WhatsApp:+86-15610128027Email:yzh@breakerboomsystem.comOnline:Submit your underground project details here

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