MechChem Africa July 2019

⎪ Power transmission, bearings, bushes and seals ⎪

forcostlyandtime-consumingadjustments. Pressure switches monitor air flow to de- tect if the ventilation motor has stopped working.Where there is littlevertical space for installing a motor, a connection kit can be used tomount a standard forced cooling unit in an axial position. Transparent doors can also be fitted to facilitatemaintenance procedures such as brush inspection, without having to remove inspectiondoors. Leroy-Somer has developed an on- line configurator to assist in the selec- tion of motors, brake motors or geared motors, combined with variable speed drives. A link to this energy savings web- site can be found at http://acim.nidec. com/motors/leroy-somer/services/ calculate-your-energy-savings The modular concept of this range enables a continuous production line for the entire LS product range, thus reducing delivery times. Lead times for adaptedmo- tors are also significantly shortened. Vert Energy also offers a maintenance programme which ensures optimum per- formance of dc motors and significantly extends service life. q “If there is the slightest imperfection in the flat surface of the join, this can cause costly damage to the drive and the screen,” says Mayhew-Ridgers. “This is why OEMs such as Kwatani havedetailed installationprocedures for issues suchas torqueingof bolts. Installers and maintenance teams need to stick closely to these specifications.” q exacting specifications. Mayhew-Ridgers notes that Kwatani has spent a great deal of effort on the sealing configuration, to ensure no oil leaks, stating that the company is probably the only OEM that services its own gearboxes. “This ensures adherence to strict toler- ances, so that units have sustained perfor- mance and longevity,” Mayhew-Ridgers tells MechChem Africa . He also highlights themassive centripetal forces that are exerted on the screening ma- chine by the unbalanced motor and gearbox, making it vital to secure them well to the screen. “To achieve this, we specify our own fabri- catedbolts, nuts andwashers. If sub-standard fasteners are used, components can come loose and cause extensive damage.” Unbalanced motors usually have to be installed at an angle. Taking account of the weight of these components, thereare rigging points all around the housing to manipulate the angleof installation. The feet arenormally larger than those of competitors, for a better contact surface.

Multi-level e-house from Shaw Controls for oil & gas sector A multi-level E-house, designed, engineered and manufactured by Shaw Controls, has been supplied as a fit-for-purpose solution at a major South African Port. S hawControls,amemberoftheZest WEG Group, has designed, engi- neered,manufacturedandsupplied a fit-for-purpose E-house solution into an oil and gas sector application at a major South African port. before transportation to site. Other important aspects of this E-house design include its fire rating, fire detection systems and HVAC systems for heating, cooling and ventilation. Rock wool mineral insulationbetween the cladding segregates themodules andprovides a two-hour struc- tural fire rating. Climate control systems will ensure that the coastal temperatures and humidity of KwaZulu-Natal do not disrupt smooth operations. q

Bevan Richards, managing director of Shaw Controls, explains that, using a draft concept supplied by the customer, the company has taken its E-house design and manufacturing capabilities to newheights. “Shaw Controls was responsible for the complete mechanical and electrical design as well as manufacture of this E-house solution, which comprises five modules,” says Richards. “Probably in a ‘first’ for SouthAfrica and accommodating space constraints on site, the design is amulti-level construction that will be fitted onto the available footprint.” This E-house solution comprises three modules at ground level with two above. The substantial structure, including all electrical substation equipment, weighs approximately 90 tonnes. A section of the groundfloorhousesamediumvoltage(MV) switchroom with a dry-type transformer for enhanced safety, and a module fitted with three 450 kW MV variable speed drives (VSDs). The thirdmodule contains a1MVAgen- erator set, sourced fromZestWEGGroup’s dedicated genset manufacturing facility in Cape Town, for backup power. The first floor comprises one module with a low voltage motor control centre (MCC) and four freestanding low voltage (LV) VSD panels, and a second module for control and automation. An additional E-house comprising onemodule for a sepa- rate (LV) substation has also been supplied. “Ourexpertiseandexperienceindesign- ing appropriate mechanical and electrical solutions using 3D modelling software makes this kind of innovation possible,” says Richards. Using a turnkey approach allows Shaw Controls to efficiently construct the full solution at its dedicated E-house facil- ity in Heidelberg, saving customers the complexity of managing multiple contrac- tors on site. At this facility, the modules are trial-fitted, assembled and tested

A view of the E-house module assembly at Shaw Controls showing both ground floor, which houses MV switchgear module and MV VSD module, and upper floor comprising MCC module and DCS/ESD module.

A view inside the LV MCC room of the E-house.

The MV VSD room of the H-house.

July 2019 • MechChem Africa ¦ 13