2,148t In 25 Days For Dormac Shipyards
Between 5 and 30 May 2026, Worldwide Load Testing Specialists (Pty) Ltd (WWLTS) delivered two compressed marine-crane proof-testing campaigns for Dormac Shipyards:
BBC Opal at Dormac Shipyard, Durban, from 5-9 May, and BBC Onyx at Richards Bay Harbour from 27-30 May.
The work supported the vessels’ five-year class inspection requirements under the attending DNV surveyor. WWLTS engineered the load application and rigging studies, supplied the water-bag, rigging and loadmeasurement systems, controlled execution, and issued test records through registered lifting machinery inspectors. Across the two vessels, WWLTS proof-tested 15 lifting appliances. The centrepiece was four NMF DK SL 400018/200030 deck cranes, each rated at 400 t and proof-loaded individually to 440 t. The programme also covered four auxiliary hoists to 50 t, two NMF DKV deck cranes to 88 t, two provision cranes to 1.25 t, two engine-room cranes to 4.2 t and 3.125 t, and one rescue-boat appliance to 2.31 t. The issued certificates verify a cumulative applied proof load of 2,148.135 t within the 25-day interval.
Project Methods and Engineering Controls
Equipment selection was governed by OEM load charts, test radii, headroom, sling geometry, component WLLs, instrument ranges and stable load sharing. BBC Opal’s 400 t load test used three 100 t, four 35 t and one 40 t water bag, a 300 t spreader, 13 endless round slings, 10 bow shackles and six calibrated load cells across six measured paths.
BBC Onyx required a different seven-bag arrangement: four 100 t, two 40 t and one 35 t bag, a 400 t adjustable spreader with the 6 m inner points selected, two 200 t/5 m steel-wire-rope top slings, and five measured paths.
Modular water-bag capacities could be combined around each vessel’s geometry without mobilising more than 440 t of solid weights. WWLTS telemetry load cells operated without interference from port wireless systems. A specialist pump supplied seawater at approximately 1.8 t per minute to a 16 m delivery head, enabling controlled simultaneous filling and return of water after testing. Before loading, equipment was checked against certificates and staged in connection order. Rigging not captured below a load cell was separately weighed as unmeasured tare, preventing the water mass from being mistaken for total suspended load.
Calibrated channels were checked from the empty-rig condition, while bag mass remained measured. Filling progressed under LMI supervision in 10 t steps to 100 t, 25 t steps from 100-400 t, and 10 t steps from 400-440 t. Dynamic functions were verified at authorised stages; the final 440 t overload was held for 7-10 minutes. At each checkpoint, a cabin LMI used radio read-back to compare the crane’s indication with the WWLTS load-cell total plus tare. Any unexplained discrepancy stopped the test. DNV recorded the results before controlled draining, inspection, de-rigging and equipment reconciliation.
The innovation lay in converting a large installed inventory into two vessel-specific, multi-tier measured load systems at very short notice. Rather than treating the test as a single nominal water load, WWLTS engineered the complete load path: top-sling angle, spreader reactions, branch allocation, bag capacity, measured and unmeasured tare, headroom, crane radius, onboard-indicator comparison and emergency de-load. The BBC Opal and BBC Onyx arrangements used different spreaders, sling sets and numbers of measured paths, yet applied the same traceable control philosophy.
The team also adapted in the field without compromising the approved load basis. On BBC Opal, the planned low centre position for the 40 t bag created insufficient headroom. WWLTS reconfigured that bag into the upper cluster, reviewed the geometry and maintained the required total and load distribution. This prevented a clearance conflict while preserving the proof-test objective. Modular bags and calibrated load cells also allowed smaller appliances to be tested during short weather windows, protecting the programme while the heavy-crane stages waited for safe conditions.
Planning, Site Conditions and Risk Control
Both mobilisations began with only seven days’ notice and three possible ports of call. For BBC Opal the options were Cape Town, Port Elizabeth and Durban; for BBC Onyx they were Walvis Bay, Port Elizabeth and Richards Bay. Final confirmation triggered rapid mobilisation, including 100 t bags from Cape Town. Dispatch delays reduced the Onyx execution window to three effective days. WWLTS responded with three staggered crews comprising six people, typically working from 05:00 to 16:00, while sequencing smaller tests around the priority heavy-crane operations.
Marine and quayside conditions were controlled through approved staging areas, vehicle restraints, hose management, waterside rescue arrangements and exclusion zones.
Weather was continuously monitored. Wet and gusty conditions affected the Opal period, so the two 440 t tests were reserved for the clear window on 9 May and completed, drained and released before daylight ended. Testing was prohibited above 8.3 m/s (30 km/h), with any lower OEM, vessel, port or class limit taking precedence. Onyx shifts likewise started early ahead of forecast deterioration.
The controlled method incorporated lift plans, equipment calculations, risk assessments, task briefings, defined radio communications, certified rigging and calibrated instrumentation, a 26-hazard risk register and 12 mandatory hold points. The work followed ISO 19356:2016, the approved test programme, OEM requirements and DNV class oversight. WWLTS retained operational control of load application, while the vessel’s crew assisted with assigned rigging and safety duties under one command structure. Both campaigns were completed with no injuries, equipment damage, lost-time events or reportable incidents.
Customer Satisfaction and Realised Efficiency
The defining client outcome was schedule certainty. BBC Opal sailed on the evening of 9 May after both 440 t tests were completed in a single clear-weather day; BBC Onyx also departed as planned after the balance of its scope was completed on 30 May.
Dormac was therefore able to fulfil its obligations without additional vessel downtime or delay-related cost. Completion and acceptance of both scopes and test records demonstrate confidence in WWLTS’s planning and execution. Dormac job sign-off sheets for BBC Opal and BBC Onyx are attached.
Worldwide Load Testing Specialists (Pty) Ltd,
+27 (0) 31 572 4940,
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