Our client, CS Energy Ltd awarded MEA the Pulveriser Mill Rejects Handling contract at Callide Power Station, Biloela. The existing system captured the Mill Rejects through a high pressure water ejector system, which required periodic cleaning of larger rejects and was prone to blockages, which in turn caused a forced outage of the entire Mill. MEA worked closely with it client to determine the best option to convey the Mill rejects effectively; A Submerged Chain Conveyor (SCC) was agreed upon. The conveyor takes the hot rejects (350°c and sizes up to 100mm), cools them to approx 50°c and conveys them via the chain flights to an incline of 24°, where it is discharged into a skip for collection. The SCC was designed for ease of maintenance and included: Removable Idler Assemblies accessible from the outside of the SCC. Chain driven Dive/Sprocket assembly with a "Sealed for Life Gearbox". Fully accessible SCC body via numerous inspection covers and bolted hatches. Shear pin design coupling to protect against any possible damage to the mechanical components. Under speed sensor to detect any possible breakage within the chain flight assembly. Wash water to all Idler Wheel Assemblies to flush any product from its sealing mechanism. Bypass chute to deflect material into a local skip, instead of discharging onto the 'future' conveyor system. The project was fully designed, manufactured, site installed and commissioned by MEA and has been operating at full capacity for some time without any causes of concern. CS Energy are now negotiating with MEA the possibility to installing an additional nine more of these SCC's across the remaining Mills and linked by a central conveyor system to discharge all Mill Rejects into one bunded stockpile.

Dragline Power Control Room (PCR)

MEA was awarded the contract to supply and manufacture a Power Control Room (PCR) for a Bucyrus - Erie Dragline at BMA Coal. The room was designed using plate/stiffener construction for the walls and Channel Lattice Frame for the Floor and Roof. Each wall, roof and floor section was fabricated and NDT tested separately, prior to being abrasive blasted to class 2.5 and prime to a 75um DFT in MEA's in house paint facility. The sections were carefully raised into place to completely assemble the room, allowing all joints to be seal welding 'air tight'. The internal walls and roof were insulated using 100mm Fibre Thermal Insulation and cladded using 1.0mm Panel Rib Surfmist colourbond sheeting. The floor was fitted with a removable 'false floor' which allowed the Electricians to run cables below floor level at a later date. The Ceiling was fitted with an air conditioning duct behind the Panel Rib sheeting, to allow cool air to be supplied to the room and its critical electrical components. The room was supplied with a suitable Lifting Frame, Chains and Lift Points, as well as access platforms, stairs and handrail sections.

Dragline Air Compressor and Transformer Blister Room

As part of MEA's multidiscipline facility and its focus on turn key projects, we are able to provide our client with a full Engineering Design office capability. As part of our mining client, 'BMA Coals' Dragline upgrade, MEA was commissioned to carryout design work to modify the House structure and include a large 'Blister Room' to the rear left hand side wall. The Blister Room included 2 x Sulair 10/30 Air compressors, enclosed with in a sealed room. The room contained two personnel access doors, as well as maintenance access via double pivoting front doors. The Transformer which weighed 4.41 T, was to be supported using a purpose built structure with full access to all sides and protected by a roof canopy. The existing stairs were to be modified to suit the new structures. Due to the additional load on the Dragline, full survey, centre of gravity and pivot checks were undertaken. MEA carried out the on site survey of the Dragline to determine the existing structural supports that would ultimately take the additional loading off the 'Blister Room'. The Engineering scope, from initial site survey to completion of 3D Modelled General Arrangements and Workshop Detailed Drawings took our design team 4 weeks to complete. (A mean tasks considering the challenges faced). The supply and manufacture is to be carried out by MEA and is due for completion early 2009.

69 Tooth Drive Bull Gear & 16 Tooth Drive Pinion Gear Set - Magnesite Mining

Designed and manufactured for "Q'Mag Ltd" as upgraded replacement Gearing for drive to their Log-Washing Plant, handling ROM Magnesite Ore at their Kunnawarra  Mine Site {Qld}. Bull Gear is of fabricated construction, utilising grade 350 carbon steel plate for the Web and Gussets, and K1045 high grade carbon steel for the Hub. The Rim is of similar K1045 steel but produced as a Roll Forged  Ring to maintain Gear Teeth strength and integrity. The completed fabricated Gear is NDT Inspected and thermal Stress Relieved, before final machining and Gear cutting. The matching Pinion Gear is machined and Gear cut from grade 4340 alloy steel forged billet. Both Bull Gear & Pinion have Induction Hardened Teeth to reduce wear and increase life expectancy!

Dragline Highwall Cable Boom / Skid - Open-Cut Coal Mining

With the current high market returns within the Coal Industry, the need to push deeper with Open Cut Mining becomes more prevalent. Draglines are required to operate from benches to access the deeper coal seams, which introduces problems with the safety and security of the main trailing HV Cable from damage sustained from the Highwall rock conditions. This was the problem facing BMA Coal's Norwich Park Mine site. MEA's design scope was for a skid mounted mobile Cable Boom, positioned at the top of the Highwall, to accept and safely project the HV Dragline Cable over the Berm and away from potential rubbing against Highwall rock faces, whilst providing the heavy construction necessary to accept their largest D11 Caterpillar Dozer's to pass over cable without damage. All these aspects were achieved and at a much reduced cost through utilising 'free issued' old Dragline Boom Cord Pipes with the main construction of this Cable Boom / Skid. The Dragline Cable runs down the center of the Skid under timber sleeper deck area, and is accessed via removable sections. Heavy duty pivoting Ramps locked in up position, along with provision of heavy construction tow/lift points at all corners, and 'Dozer Push Bars' at rear end, allows ease of mobility and haulage of Cable Boom / Skid from mine pit to mine pit!

Dense Phase Fly Ash Dust Vessels - Power Generation

New manufactured and tested Vessels for C S Energy's dense phase system handling Fly Ash Dust from Electrostatic Precipitators at Callide Power Station, to replace existing units with thinning of the walls due to heavy internal wear / erosion. New Vessels were constructed from grade 460R certified  boiler plate steel to Pressure Vessel Standard AS1210, with full NDT inspection of all welds and thermal Stress Relieving of completed fabrication. New 70mm thk Top Plates were sourced from the same boiler plate grade and NC machined to finished tolerances. Completed Vessels & Top Plates were shop assembled and successfully passed Hydro-static Pressure Testing, before Surface Protection (blast/paint) with heat resistant aluminium silver Epoxy, and QA documentation completed for registration as 'Unfired Pressure Vessels' Plant.