Mdm march april 2015 website

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Mine Site Rehabilitation Rehabilitation of the mine site can simply be defined as the processes or an activity that aims at restoring land that is not active and has been abandoned to a productive state in regard to natural habitats, soil productivity, and fresh water thus enhancing its sustainability its beneficial uses and achievements of specific social economic outcome.

When mine sites and quarries are abandoned they are prone to pollution caused by dumping of pollutants materials by the community members, insecurity which comes in due to lack of warnings and fence, in order to protect the land from the above calamities there is need to enforce rehabilitation program.

Rehabilitation program entails the following: Identifying the context of the rehabilitation plan, setting of the objectives for the program, developing the program, implementing the rehabilitation plan, management and monitoring of the program, closure of the program and finally follow up. The objectives should be realistic,

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measurable and time bound so as to achieve maximum effectiveness. It is also important to assess all risks associated with these objectives so to facilitate positive income, for these objectives to be achieved there must be adequate resources both financial resources and man power.

Rehabilitation program should be able to meet the following key requirements: Legislative requirements, safety and health of the area, economic viability and a possible positive economic impact to the local communities, create stable aesthetic landforms within the area, development of the area in accordance with local people cultural and beliefs in addition to hope and aspirations of all stakeholders, consider alternative reuse of the area, ecological sustainability, economic development, minimize soil erosion and reduction in maintenances requirements of the rehabilitated area.

Safety and healthy measures should be considered as integral part of rehabilitation and taken into action so as to minimize hazardous damages left

behind by mining activities such as: emission of chemicals into the ground leaving heavy metals that gets contaminated with soil and water, pits and pots, falling rocks, unstable ground, high toxic gases, explosive fluids and dangerous shafts which in turn poses threat to the general habitat endangering its existence. Alternative reuse of the abandoned mines and inactive quarries includes establishment of activities which are beneficial to the community such as using pits from these area such as water reservoirs and installation of sewage plants, open air museums which attracts tourism and can also be used for educational purposes.

Local people's cultural beliefs, wishes and hopes should be considered in rehabilitation program and in reusing of the mine site because they are the beneficiaries and they are the ones affected, this is achieved by involving them in decision making and taking part in the projects activities and the end results is sustainability of the project.

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Published by: E.S.C Magazine T/A Projects Publishers 62, 2nd Avenue, Houghton, 2198 P.O. Box 92744, Norwood, 2117, Johannesburg, South Africa.

Tel: +27 11 346 5053 Fax: +27 86 601 9195 Writers Briget Wangeci Editor Florence Nyaguthii Designer/Writer Moses Email: info@miningdevelopmentsnews.com Website www.miningdevelopmentsnews.com The Publisher does not accept any responsibility for the accuracy or authenticity of the contributions contained in the Magazine and advertisements. Views expressed by the contributors are not necessarily those of the Publishers. Š All rights reserved

eDITOR

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Heat Exchangers Equipments

Heat exchangers can simply be defined as the equipments used to transfer heat from a hot fluid flow to a cold fluid flow. Heat exchangers are basically classified based on the following criteria: Flow arrangement, nature of heat exchanger process, physical state of the fluid and the construction and geometry of the heat exchanger.

Classification based on heat exchanger processes is achieved in either of the following ways direct contact or indirect contact, direct contact is whereby heat transfer processes involves direct mixing of the two fluids while in the case of indirect contact heat transfer of the two fluids occurs through a separate wall and this process is

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known as thermal conduction.

Classification based on flow arrangement is determined by the relative directions of the two fluid streams, which can be parallel flow, counter flow or cross flow heat exchangers.

Heat exchangers equipments are designed into many different styles but the most commonly used are the shell and tube heat exchangers. Others are modified for other specific applications for example the plate fin heat exchangers used for single phase heating and cooling with low temperature and pressure where the fluids been processed are non

hazardous, open flow heat exchangers mainly used for final heat release from liquid to air, contact heat exchangers applicable where simultaneous heat and mass transfer takes place, double pin heat exchangers are applicable in small heat transfer areas that involves single phase heating and cooling, hairpin heat exchangers they are applicable where the heat transfer area is relatively small and where there is high pressure and temperature between the shell and tube fluids, spiral tube heat exchangers, spiral plate they are fabricated from coiled tubing and are applicable for small services such as pumping sea fluid, air cooled heat exchangers are mostly applicable in areas where water

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is insufficient.

The shell and tube heat exchangers originated from jacketed coil distiller they are the most used because they are available in a wide range of configurations that is they can be configured for condensing, vaporizing, liquid to liquid or gas to liquid. These shell and tube heat exchangers comprises of the following key elements: Shells, tubes, nozzles, tube sheets, baffles, tie rods, shell cover, channe

cov er and channel.

Shell and tube exchangers have got the following benefits: Availability in many different materials and sizes, compact design, cost effective, easy

mai ntenance and availability of many manufacturers as compared to the others.

All heat exchangers requires maintenance and proper management through various heat exchanger inspection methods, thorough cleaning in addition to proper installation

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March/April 2015 Issue

Industrial and Medical Gases Gas refers to air substance that is capable of expansion and ability of been filled in any available space. Gases are grouped into five distinct categories that is: Medical, industrial, specialty gases, refrigerants and fuel gases. Medical gases are those used in the field of medicine and examples are medical oxygen, medical carbon dioxide, nitrous oxide also known as laughing gas, helium which comprises of the oxygen and the nitrous oxide. Industrial gases on the other hand refer to those gases that are manufactured for industrial use they include: Carbon monoxide, hydrogen, nitrogen, oxygen, acetylene and carbon dioxide.

Medical gases require proper handling and therefore all regulatory requirements and protocols should be adhered to. Some of these regulatory requirements are confirmatory of the facilities used to manufacture, process, and package these gases for distribution by the Current Good Manufacturing Practice for Medical Gases in addition to Statutory Regulation. Regulatory measures helps in preventing deaths and ill health conditions which can arise due to mishandling of these gases through: Inadequate quality control unit, mislabeling, inadequate training, use of

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poor equipments and poor testing procedures.

Gasoline filling solutions for both medical and industrial should be taken care of through the following ways: ensuring that they are tested well by use of high technology facilities, proper training should be offered to the operators, repairs and maintenance should also be done to them so as to enhance their performance and their efficiency. Some of these filling solutions are: industrial gas filling equipments, medical gas filling equipment, supervision systems, high pressure pumping gas equipments, liquid filling systems, explosive gas filling equipments and high pressure line control equipments. Supervision system solutions should be computerized so as to give accurate and reliable results, the used computerized systems in manufacturing, processing and housing the end products should be able to control and prevent unauthorized personnel and be able to detect any changes as well as keeping record of those changes.

only and the buffer skid for temperature, pressure and buffer control, these pressure line equipments are designed to control the following: buffer pressure, vaporize outlet temperature ,air supply and control of the buffer valve opening. The buffer skid has got the following advantages; reduced time in filling, avoids line overpressure due to its ability to absorb the liquid gas trapped in the vaporizer and its ability of been used as secondary source for minor components of gas mixtures. All gases should be kept in secure places and marked in ways that they can be easily identified so as to avoid mix up.

High pressure line equipment are of two type: The discharge gas control panel for temperature and pressure control

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NDT Inspection Solutions NDT is derived from the name Non Destructive Testing methods, it entails techniques used in inspection and detection of harmful changes in any structures such as damages, corrosion and cracks without causing damages to the materials being inspected and provides best results for corrective measures, it is used to assess components in plant, pipe systems, vessel, pipe construction and various kinds of engineering structures. The commonly used NDT methods in evaluation of materials are: magnetic particle testing, visual inspection, liquid penetrant inspection, ultrasonic testing, radiographic inspection and Eddy current and electromagnetic testing. NDT plays an important role in quality control of the manufactured products by enhancing reliability, safety and compliance to legislative requirements.

Magnetic particle testing is one of the most used NDT techniques since it is faster, easy to use and does not involve surface preparation; it uses magnetic particles to detect flaws in components whose materials can be magnetized, the test specimen is magnetized by use of either, permanent, electromagnetic or by passing electric current around it, usually the magnetic field introduced in this specimen has got magnetic lines of force and whenever there is flaws it interrupts this lines by existing and reentering the specimen, this helps to create visual indication giving approximation of shape and size of the flaw, magnetization techniques

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are categorized into: direct current techniques whereby current flows through test specimen and the magnetic field, it is used to detect defects and the magnetic flux techniques in which magnetic flux is induced into specimen by use of permanent magnet or flowing current through a coil or a conductor.

Visual inspection is an important method of non destructive testing technique it works by visual detection of the surface; it basically relies on evaluations made by use of eyes, its efficiency is facilitated by the following factors: proper eye sight of the tester, knowledge on the product and good lighting. Visual testing is classified as direct, visual and translucent visual testing, there are various scientific devices used to aid visibility while using visual testing they include: inspection glass, bore scope, hand magnifying glass, illuminated glass and mirror on stem.

Liquid penetrant testing technique is used to test non magnetic materials in this case surface flaws are revealed by placing surface of the product to a penetrant liquid against a contrasting background where it remains for a predetermined time, the excess penetrant is removed from the surface, the surface is then dried and developer is applied on it whereby it reverses this action and draws penetrant from the flaw, this indicates size, location as well shape of the flaw.

visible or fluorescent penetrant, visible penetrant produces a bold red line or a strain against a white developer background when observed under white light while as fluorescent penetrant produces a green line when observed under black light.

Radiographic testing method is used to detect internal flaws in different materials, short wavelength electromagnetic radiation are passed on specimen material, intensity of rays while passing in the material is modified according to the internal structure of the material and exposed on a film, areas of reduced thickness absorbs less rays and appears as dark areas on radiograph and areas of high absorption as light areas and the results obtained are interpreted whereby flaws present are identified. Ultrasonic testing technique is an inspection method that uses high frequency sound waves to measure physical properties in materials. The Eddy current testing is applied to electrically conductive materials only, a coil carrying an alternating current is placed round the specimen, where they generates and circulate eddy current in specimen close to the surface thus affecting current in the coil by mutual induction, flaws present affects strength of eddy current and they are measured by electrical changes in the exciting coil.

Penetrant used to display results are either

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Global Future Trends in Fire Safety Whatever the future has in store for fire safety, one thing that is absolutely certain is that the fire fighters and every fire service personnel will always be there. Always focused, determined and working diligently to ensure that the fatality rate and fire injuries are minimized, reduction in property damage by fire, ensure that there is a conducive environment for everyone and that the climate remains safe. For global future trends in fire safety to be implemented, it is important for all governments and universal leaders to coordinate their interests and opinions aimed at improving and sustaining fire safety. Other significant approaches include; technological innovations, high public awareness on fire safety, well studied and improved building codes, excellent fire training and more resources and energy put on research.

The future fire safety trends are aimed at; a generically improved technology based on fire safety, more intervention to reduce fire frequency rates, to control the increased rate in fire burn due to the

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highly combustible materials used in furniture and construction and it is also aiming at reducing the growing rate of building collapse as a result of fire and poorly structured buildings. In addition, fire safety trends are assessing the forest fire risks and innovating the necessary and the best strategies for wild fire prevention, implementation of the overtime analysis of changing residential fire dynamics and the implications on firefighters in order to reduce the tragic and gruesome loss of lives of fire fighters and the civilians and further improvement on aircraft fire safety in order to reduce the fire risk associated with the increased air traffic.

and most importantly environmental friendly and with absolutely no negative effect to the ozone layer.

In matters good environment and absolutely good climate, future fire safety trends are concerned and focused on protecting the ozone layer. The climatic and environmental goal of protecting the ozone layer can be achieved by the use of sustainable technology. This is a fire safety method that is expected to put out fire effectively, easy to install and maintain

Transforming these future trends into innovations will only start morphing into reality only when there is sufficient monetary fund globally and when every person is fully aware of the pros and cons of fire safety.

Fire safety intends to cooperate with the building codes and update the building codes. This will help reduce the risk of collapsing of buildings which is caused by the use of synthetic materials in construction and the construction of high ceilings and open floor plans which increase the rate of fire burn and high risk of collapsing. This will also be curbed by the use of quicker fire detection systems and the use of faster response facilities and highly improved telecommunication systems.

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Electrical machinery and installation

Electrical installation is a process in which electricity is transmitted from one point of control to a point of consumption anywhere on the premises; installation works entails the following activities connection of machinery at the supply terminals, extension and repair of an electrical installation, testing and inspection of electrical installation and testing and verification of installation. It is mandatory for installation electrician to have registered with electrical regulatory body in accordance with the terms of regulation and must have a certified copy of accreditation from the accreditation authority. Electrical machines are the equipment used in transmission of electricity; they are classified into Direct Current (D.C) and Alternating Current (A.C).

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Classification of electric machines is based on electric power supply, stator and rotor construction and National Electric Manufacturers Association Standards whereby their products are classified based on their operating features, quality, rating, testing, tolerances as well as composition.

Direct Current electric machinery are classified into permanent magnet and wound field, the Alternating Current on the other hand are classified into synchronous and induction, the A.C are used in large numbers in modern industry due to their advantages which includes: cost effectiveness, robust, higher speed, simplicity, ease of maintenance and simplicity.

Electrical machines have got the following features: Rigid frame, slot whose purpose is to offer mechanical

support and protection from abrasion, brushes which acts as an interface between external circuit and the armature winding, armature winding which refers to continuous winding which has neither beginning nor the end and it is composed of a number of coils in a series, rotor which is cylindrical in shape and it carries the armature winding, stator which is a hollow cylinder made of magnetic circuit and its function is to carry the field winding, the Commutator which rotates the rotor and it plays role of rectifying the induced voltage. Electric machines are applicable in some of these areas: Gasoline engine drives, compressors, air handling equipment, electronic locomotives, wind energy turbines, blowers and fans, conveyors and crushers.

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Electrical machines are subjected to defects which include mechanical failure of rotor, vibration and noise bearings and mechanical faults of the stator, but the good news is that this

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problem are reversible upon early detection through extensive testing.

Routine test program entail: Bearing control, short circuit test, insulation control, voltage test, vibration

measurements, resistance measurements and it is important to identify problem by performing generator functional test.

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Keestrack - SA Crushing & Screening Equipment

Our Experience Your key to Success

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Underground Communication And IT Solutions Excellent underground communication and IT solutions give room for enhancing efficiency, safety and significant productivity in the mining industries. This is in both conducive and harsh mining environment within a given underground mining industry.

Perfect underground communication and IT solutions consist of reliable, upto-date and effective technologies as well as skillful personnel, who exercise underground intelligence and expertise to ensure safety and productivity through effective asset monitoring.

Communication and tracking for underground mines that is digital in nature meets the underground communication infrastructure as well as

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a real time transfer of data. With the incorporation of features such as LAN Wi-fi protocol or Wi-fi digital system, effective communication and quality data is achieved allowing productivity in the underground mines. A tracking system that is Wi-fi based acts as an effective safety tool as it effectively helps monitor the mining machineries such as vehicles as well as personnel working underground. Other benefits that come with such a tracking system include its ability to allow video cameras, phones and also PCs operate underground plus enabling automation.

Detection systems for mines can as well be implemented for underground mining. For instance, proximity

detection system, which is in other words known as Collision Avoidance System (CAS), is a detection system that is designed to prevent the risk of personnel coming into contact with the underground mining machineries in a manner that cannot be controlled.

Cap lamps are another type of underground communication solution to the underground mining. A cap lamp that can be considered competent as compared to other camp lamps is the Integrated Communications Cap Lamp (ICCL) inbuilt with features like personal protection equipment and communication equipment such as PED text message reader.

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Underground wireless communication is also recommended as a solution to underground communication for underground mining resources such as coal. This is due to the beneďŹ ts that come with underground wireless communicatio n. First, it covers a long range of distance; current frequencies permit rum for approximately 20-50 km LOS connecting clients. A high speed that allow up to 50 Mbps bandwidth and it is

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also secure since it uses encryption of a higher standards.

For the most critical underground mining environment, underground mesh radio communication is recommended as the best solution. Full wireles s mesh network 's ability to allow a given node connect with another in communication in the mining site allows consistent communication even as the site changes with continuous

underground mining.

Underground mesh network does also support automation, data communication between heavy machines and also monitoring the performance of such machines.

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Emergency Preparedness for Mines Emergency preparedness in mines is a very important aspect in that it helps mines operators control injuries and accidents incidences during the mining operations thus been able to mitigate further damages. Effective and efficient emergency preparedness is achieved based on proper risk management processes for the mines together with the availability of resources. These resources and risk management processes must be able to deal with the following: give warning information about emergencies, control the hazard causing the emergency, have control of the backup services and facilities for the emergency, isolate areas of accidents from been accessed, first aid and training on first aid, detection of hazard and be able to respond appropriately to emergencies.

The system used to control emergencies in mines should poses the following features: ability to identify risks , ability to carry out emergency exercise, ability to reduce risks associated with emergency situations, ability to audit

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and review emergency exercises and also ability to aid rescue and escape of people from the mine during the time of emergency. The following dangers are likely to occur once persons in mine are exposed to accidents and hazardous areas while undertaking their activities in mines: Electrocution, contact with harmful substances especially toxic gases and fluids, high temperatures, exposure to viral and bacterial infection, too much cold and traumatic experiences, in order to avoid the above its very important to formulate effective Emergency Response Plan.

Emergency Response Plan is a written document and it should always be made accessible to mine workers at all times, these written documents should have the following features in it: Information pertaining the mine, plans and drawing, first aid supplies, first aid training, contact list, emergency equipments, incident control, communication systems, records, clearly outlined procedures on controlling hazards, contact list and information on how to

secure the site. Plans and drawings should clearly indicate old mines workings and locations such as helicopter landing areas, marshalling points, toxic areas, and first aid kits location.

When workers are subjected to injuries it's critical to provide them with best medical attention soon enough and most of the time transportation is required, emergency response plan should incorporate fast and easily accessible means of transport such as ambulances and rescue helicopters. Mines should provide detailed information of their site to the rescue team for instance Helicopters should have a designated area for landing and the following factors should also be considered: longitude, latitude, possible hazards, contact details, availability of fuel and other possible obstruction while landing.

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Condition Monitoring Systems Systems or machines are by all means vital in the daily undertaken activities that could not be easily done by human strength. These activities are especially in the industrial fields and the mining sectors to name just but a few. Unlike man, who can harmoniously detect a breakdown of his own body system and act by himself without hurting others, systems break instantly and man, who effectively controls the systems cannot easily escape the dangers the come with a system's breakdown; fatal injuries and even immediate deaths are not easily gotten away with. However, such fatal emergencies can be avoided in advance.

This is only via implementation of condition monitoring systems.

Condition monitoring systems are available in different versions; they can either be portable or online. Portable systems for condition monitoring are ultimate for inspections and appropriate diagnosis in the machine park.

Examples of them include data collectors plus vibration analyzers.

Online condition monitoring systems on the other hand are ideal for automatic detection of changes in the conditions of a machine; they work autonomousl y

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thereby making them accurate in timely detection of possible breakdown.

With the latest technology, there are special portable condition monitoring systems that play multiple roles in ensuring conditions of machines. Such a system is the VIBXPERT II, which is an all-in-one data collector, field balancer as well as a vibration analyzer. A number of its special features include; user friendliness and intuitive operation, automatic switchbox support, fast measurements by use of trending spectra, long-lived battery as well as powerful diagnostic tools for troubleshooting machines. Abnormal vibrations produced by rotating machines as a result of unbalancing, misalignment, defective bearings, looseness and gear damage. Though the vibrations are experienced at intervals, VIBXPERT II is well inbuilt with tools to curb and to eradicate the problem.

VIBXPERT II Balancer as a portable condition monitoring system that is portable, fault of unbalancing especially with the rotors equipment can easily and powerfully be handled. The balancer helps detect unbalances effectively thereby correcting the fault in advance.

VIBXPERT II has with it special features that have shaped its outstanding performance, which include one-hand

operation that is manageable, powerful reporting tool, upgradability to vibration analyzer, 1 and 2 plane field balancing as well as machine diagnostic and integrated vibration analysis.

Online condition monitoring systems are fast, reliable and powerful to protect assets such as machines with very high end technology. VIBGUARD is an example of advanced online condition monitoring system, which has 20 parallel channels, intelligent data reduction, DIN rail mountable, various configurations, continuous monitoring and seamless integration to control systems. It is most compatible to offer parallel and synchronous data acquisition, protects assets from unplanned shutdown and carries out high diagnostics to ensure high rate of productivity and measures time signals for all kinds of signal inputs. In order to perform in high depth of analysis and monitoring of turbo machinery, the VIBGAUARD is connected to the buffered outputs of real time protection systems. It is also swift in data processing, thus, it is suitable for protecting assets with much shorter running cycles like the machining tools and cranes. VIBGAUARD It is effective and offers high level of troubleshooting as it is also available in the portable version.

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Monitoring Devices and Protection Solution in Mining Industries Mining operations are carried worldwide in search of minerals and quality metals for the purpose of economic development, this operations involves extraction, processing and transportation. Mining processes exposes miners into dangers which may cause health problems or even cause death, this operations can also damage machines and equipments used while mining and therefore it is very important to take measures and procedures that aims at achieving safety of the miners, efficiency and durability of the equipments in use which in turn saves on cost and facilitates efficiency of the mining operation. This procedure entails deployment of monitoring devices together with protection solutions.

Monitoring and protection devices in mining are classified into: accessories, vibration solutions hygienic solutions and the communication solutions.

Accessories solution for the mines includes the following: Connectors, calibration units, fibre optic cables, enclosures and safe mounting hardware.

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Mining industrial hygienic solution comprises the workers safety equipments such as protective foot wear, head gear, helmets and the air mask, other examples of the hygienic solutions are the handheld equipments used for portable analysis and the acoustic calibrators. The vibration monitoring solutions includes: Sensors for high temperature, corrosive environment, hazardous environment, underground approved sensors, transmitters, switches and wireless solutions used to reach dangerous and hard to reach areas.

Communication mining solutions offers a comprehensive communication networks that are capable of meeting the mining industry needs and this helps in enhancing reliability. Effective and efficient communication monitoring solution should be able to meet the following features: flexibility so as to allow ease of any future change, should poses high speed performance, should have ability to support multiple applications simultaneously, should have low or reduced maintenance cost,

capable of facilitating faster response and should have a long range performance for control and monitoring.

Communication processes requires secure and reliable networks for it to operate in the right way and for this to be achieved there must be professional services whose function is to plan, design, implement and commission communication services, there must also be comprehensive network management software for monitoring mining operation and the assets in use and this is attainable by use of rugged wireless, hardened Ethernet switches and multiservice telecommunications platforms.

Approved monitoring and protection devices which are fully tested and rated are able to withstand harsh environment due to their design package which allows them to withstand high temperatures and vibrations without wearing out.

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Crushers and Conveyors coupling assures a faster and more efficient unit exchange were either the gearbox or pulley has failed, drastically reducing down-time and product losses.

Drive units sent to C.I.S for repair will be completely stripped down; all the parts are then carefully inspected to determine the reason for possible failure. A detailed quote will follow stipulating the necessary parts needed for the repair as well as the pricing, delivery and warranty periods. Our repairs cover many manufactures i.e.

Fenner, SEW, Flender, David Brown, Weserhutte Mixtec, Bauer, Hansen and Renold Croft.

Conveyor Belting As importers and distributors of belting, C.I.S' Belting division has sourced a world class belting manufacturing group who manufacture our belts in accordance with: Ÿ R.M.A – Rubber Manufactures of America Ÿ J.I.S.K – Japanese Ÿ D.I.N – German Ÿ B.S. – British Ÿ A.S. – Australian Ÿ M.A.H.S. – United States of America Ÿ S.A.N.S – South African National standards.

C.I.S supply a full range of multi ply and steel cord belting for all applications and we are able to supply specialised belting including belting with sidewalls and cleats, elevator conveyors complete with steel or polyurethane buckets etc.

(H Frames) and Stringers in accordance to SANS 1313 specifications, in addition to which our unique bearing housing has proven to be both reliable and robust in operation.

One key feature is the large flinger which gives the roller the advantage in areas with spillage. It has been noted that C.I.S' roller has reduced customer idler consumption by 40% in one year.

Our standard idler roller consists of: Ÿ SANS 3.8mm thick wall conveyor idler steel tube. Ÿ Glass filled nylon bearing housing and triple lip flinger. Ÿ 6205 rubber sealed for life bearing with a C3 clearance. Ÿ Conveyor idler steel shaft. Ÿ Red oxide coating to minimise rust.

Pulley Manufacturing Repairs C.I.S' Pulley Manufacturing & Repairs division manufactures a wide range of pulleys including Turbine, T top, grease filled, oil filled, spiral pulleys etc which are manufactured in accordance to SANS 1669 specifications. We offer various lagging options including ceramic tiled, ceramic paste, hot vulcanized rubber lagging etc.

As most worn pulleys can be repaired to their original state, C.I.S is fully equipped to repair and refurbish all

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In addition to this, C.I.S is able to supply a unique mechanical rip stop in the form of transverse wires which are imbedded in the belt. The transverse wire is a galvanised steel cord that runs the width of the belt ranging from 1.5mm to 2.5mm thick with a pitch of 6mm to 14mm depending on the class of belt. These cords run the full width of the belt which provides the advantage of good impact and reduces tears caused by external forces.

Gearbox Manufacturing and Repairs Our capabilities stretch beyond the everyday repairs and manufacturing of speed reducers. C.I.S offers a proud range of bevel helical reducers from 22kw to 315kw, all reducers are designed and manufactured in-house and are available with the lantern housing or base plate type arrangement, along with a fluid drive and electric motor of your choice. C.I.S have more than 20 years of expertise in the manufacturing of bevel helical speed reducers and have supplied units to the local and international mining industry.

Conveyor Idlers C.I.S' Conveyor Idlers Manufacturing division has the capacity to manufacture a wide variety of Idlers, Frames, Stools

C.I.S specialise in change over modifications from hollow shaft mounted arrangements to the bikon rigid coupling assembly. The rigid

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CNC Machining and Milling Our CNC Machining and Milling division is constantly expanding and keeping abreast of the latest in technological trends and boasts ten machines dedicated to manufacturing various parts for the gearbox, pulley and idler divisions as well as high volume general engineering.

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Our engineering division to ensure pulley information meets with SANS specifications. Our engineering division is also on hand to assist our customers with with full pulley designs etc.

Stretch Wrap Machines This is a must for the packaging industry as these machines and all accompanying mechanical components are manufactured in C.I.S' workshop.

Our stretch wrap machines have become very popular within various industries including: Farming, Bottling, Printing, Chemical etc.

KEY FEATURES OF THE MACHINE: Ÿ Pre Stretch Dispenser (provides you with tighter wraps using less plastic) Ÿ Banner Eye (Automatic reading of product height Ÿ Variable Speed Drive (pre setting of the top speed as well as the ramp up time) Ÿ Hard Wire Electric Panel (380v panel built for reliability) Ÿ Turn Table (1.5m diameter to handle standard pallet sizes, supported by 26 bearings with a weight capacity of 2.5 tons.

makes of pulleys. All repairs include a one year manufacturing default warranty.

C.I.S is able to manufacture 2.5m Ø pulleys suitable for all belt widths. Our standard manufacturing practise when welding end plates to shells is to use submersible arc welding to ensure maximum penetration; in addition to which a minimum of 2mm is skimmed off the face to eliminate run out.

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Refuge Chambers and Safe Havens in Mines

Refuge chambers and safe haven are an integral part of Emergency Response Management, they are used to offer safety of the mine workers awaiting rescue during emergencies posed by irrespirable atmosphere conditions that are likely to endanger their lives, some of these harmful conditions are: toxic gases, fire, floods, explosives, collapse of old walls, dust, smoke and tailings.

These dangers are likely to occur more frequently and therefore it is of paramount importance to conduct risk assessment in mines so as to detect and come up with ways of mitigation. Risk assessment plan should be able to

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identify health hazards, assess the identified risks and make possible changes to reduce risks and injuries to the affected persons.

An effective chamber should be situated in areas that are free from non combustible materials in addition measures and procedures that ensure its readiness at all time should be imposed.

The following requirements should be considered when installing and utilizing safe haven and refuge chambers :construction and design, Emergency procedures, legislative requirements, sufficient training, location of the

chamber, ventilation systems, food and water , sufficient air, toilet facilities, means of egress, tunnel design, sirens, seals, internal lighting, pressure equalization systems, communication systems, capacity of the chamber, gas monitoring equipments, first aid equipments, power supply , emergency backups, doors which are easily accessible, towing and lifting points.

Construction and design of a refuge chamber should ease its usage as well as its movement these chambers are mostly made of robust equipment so as to minimize damages arising from

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vigorous movement, all seals should be in good condition so as to prevent contaminants from getting in, it is important to have an alternative means of egress incase the main access is blocked and these escape hatches should be possible to open without difficulties, pressure equalization systems plays a vital role in that they control and maintain internal pressure at a level above that of outside, communication systems are essential part of a refuge chamber because they link the rescue team and the persons been rescued thus enhancing management of the emergency.

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Efficient refuge chambers and safe havens should be able to operate in the following complementary modes: stand by, stand alone and externally supported. Externally supported mode is where by an incident has occurred and the chamber is occupied with respiratory atmosphere from a reliable external compressed air supply, stand alone is a situation in which there is disconnection of external power and air and the chamber is fully occupied and has the ability of providing life support to the occupants in addition to conditioning atmosphere of the chamber atmosphere with acceptable limits of heat and humidity, while as stand by mode is a situation in which the

chamber is unoccupied and no incident has occurred but it is ready for an emergency use.

Refuge chambers and safe havens needs to be taken care of so as to enhance their performance, longevity and efficiency these is achieved through the following: Inspection which entails; checking of any malfunctions of refuge chamber systems, cleaning of the chambers equipment as per manufacturers direction, checking of the worn out equipment, maintenance and repair of the problems identified during inspection, testing of the chambers performance as per the manufacturer's instructions

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Uranium Uranium is a natural occurring mineral element, it is a silver colored metal that is radioactive, it is found in varying trace amounts in rocks, plants, animals, soil, water, rocks and humans. Natural uranium constitute three isotopes which are uranium -234 present at 0.0054%, uranium -235 present at 0.72 % and uranium -238 which is present at 99.28% in nature. Uranium can be found in the following three forms: volcanic, sedimentary where uranium deposits are found in sediments and hydrothermal where it is formed by combination of heat and water deep within the earth's crust.

Depleted Uranium differs from natural uranium by having most of its u-235 and u-234 removed so as to enrich it for nuclear fuel weapons and it closely resembles natural uranium in terms of physical, chemical toxic properties.

Uranium minerals are mined through the following ways: In situ Leaching, underground and open pit mining, underground mining is suitable where ore bodies are found deeper in the earth, underground mining process requires specialized equipments for conďŹ ned places, proper ground support, good ventilation and efďŹ cient tunnels. Open

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pit mining is applicable where ore bodies are found close to the earth surface, it is very economical and the only challenge is that it creates land disturbances. In situ leaching mining methods are applicable in perme able mat eria

ls suc h as gravel and sand, weakly acidic and alkaline water is pumped into ore body where the uranium is dissolved and extracted. Uranium materials are used for both military and commercial purposes.

The most commercial application is the manufacturing of nuclear fuel used to

produce electricity in nuclear reactors, other commercial usage includes medical systems for radio therapy, industrial radiography equipments, coloring pigments for jewels, porcelain and glasses, and it is also applicable in aircrafts as a counter weight. Military application it used in production of the atomic bombs and nuclear weapons.

Uranium is radioactive element due to instability of its atom, the energy emitted during this process is called ionizing radiation, uranium has got three ionizing radiations which are alpha, beta and gamma radiation. Their exposure to human occurs either internally or externally. Alpha particles consists of helium nuclei they are only hazardous when ingested or inhaled, beta particles are electrons and are hazardous upon exposure with direct skin contact, gamma rays travels at a light speed and are capable of penetrating deeply into human tissues.

Uranium radiations can be avoided through: Follow ups of the safety and radiation procedures, appropriate disposal of the contaminated materials, use of approved protective gadgets and avoidance of the restricted areas.

March/April 2015 Issue

SUPERWATT TO POWER SWAKOP URANIUM'S HUSAB PROJECT Founded in 2006 in response to the growing demand for back-up power solutions in South Africa and Africa, SUPERWATT (Pty) Ltd, the Cape Town based Power Solutions company, has become a leader in supplying turnkey applications with modular platforms, including step-up or step-down transformers which allow for the future expansion and reconfiguration of the back-up power systems.

Based in Cape Town, with national representation, the Superwatt head office includes a storage facility, which is a “Customs Approved Bonded Warehouse”. This makes it an ideal transit point, as well as being free of Southern African Customs Union (SACU) Duties and VAT for the export of installations outside of SACU countries.

The strength of Superwatt is the ability to design custom projects through a hands-on approach and efficient service. Superwatt is involved from the concept and design stages, through to the installation and commissioning of products, followed by a maintenance contract if required. Each client's needs are individually assessed and designed, which surpasses just fulfilling a market standard. Larger power generating sets are assembled using engines from global, leading manufacturers. These include Perkins (UK), Cummins (USA) and MTU (Germany). Alternators are provided by leading alternator manufacturers Stamford UK, Leroy Somer and other well-known brands.

In 2014 SUPERWATT (Pty) Ltd was awarded the contract for the supply and installation of the standby power plant for Swakop Uranium's HUSAB Project, and the project is currently well underway, scheduled for completion in August 2015. The HUSAB Project Joint Venture, comprising AMEC, the international engineering and project Management Company, and Tenova Bateman, is a reimbursable contract for the engineering, procurement and construction management of Swakop Uranium's HUSAB Project near Swakopmund in Namibia.

March/April 2015 Issue

The HUSAB project is owned and operated by Swakop Uranium, a wholly-owned Namibian subsidiary of Taurus Minerals Limited, an entity owned by China General Nuclear and the China-Africa Development Fund.

Swakop Uranium's HUSAB Project is the largest in-situ, and highest grade, granite-hosted uranium deposit in Namibia, and currently the third-largest uranium-only deposit in the world.

The HUSAB uranium deposit is located approximately 45 kilometers northeast of Namibia's main port, Walvis Bay, in the same area that holds several world-class uranium deposits and mines, including Rössing Uranium and the Langer Heinrich mine.

Based on a Definitive Feasibility Study, the HUSAB Project is being developed as a largescale load-and-haul, open-pit mining operation, with ore from the mine feeding a conventional agitated acid leach process plant, at a rate of 15 million metric tons of ore per year. With anticipated annual production of approximately 15,5 million pounds of uranium, the HUSAB Project is set to become the second-largest uranium mine in the world.

Superwatt's diesel standby modular power solution to the mine will comprise seven 2MVA prime power generators in combination with eight 4MVA step-up transformers. A single 33kV/14MVA cable will feed the emergency power to the mine's substation. The project is offered as a complete turnkey solution and includes fuel and oil storage and filtration, a centralized generator control room for the system, and an interface with the mine's information and control center. The generator control system will be integrated with the intake substation allowing automatic synchronization to the NAMPOWER grid at 33kV. The system will support either stand-alone operation; or run parallel in a “mains co-generation operation”.

The latter mode has multiple uses which include peak power demand reduction; fixed power export per generator, testing or exercise runs; or

on-demand load reduction.

Superwatt is becoming known in Africa as the turnkey solutions based supplier of modular platforms. Typical equipment includes containerized generator sets, step-up transformers for MV applications, MV switchgear, fuel storage tanks, pumps and filtration units, etc. Optical fiber interconnection is offered for bigger installations to ensure true electrical isolation between generators and also to guarantee 100% signal quality between the various controllers. Modularity is enhanced by the fact that the generators are designed to function either as single units, or as multiple units in parallel clusters without the need of external synchronising panels.

Superwatt is no newcomer to building Power Plants in Africa. In Namibia Superwatt has completed two contracts for Uramin Namibia (Pty) Ltd – part of the French nuclear giant Areva. Phase one was for a 6MVA synchronized solution providing the primary source of electrical power for the commissioning of the desalination plant about 30km north of Swakopmund. The second phase known as the Trekkopje Maxi Project, consisted of 9 generators, totaling some 12MVA and was completed in February 2012. This phase saw 4.5MVA of the 6MVA relocated from the desalination plant to the Uranium mine in addition to 6 new generators to increase the generation capacity to 12MVA prime. Approval was obtained from NAMPOWER to synchronize to their grid at 33kV. This functionality was subsequently added to the Trekkopje site, enabling the plant to export power to NAMPOWER on demand.

Superwatt (Pty) Ltd is also active in North Africa, with the first phase of a 28MVA modular installation including all civils, tanks and overhead lines reaching completing in June 2015, after which the 2nd phase is scheduled to commence.

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