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ROTARY KILN & ROTARY VESSEL SERVICES

DGC AFRICA provides specialist Rotary Kiln & Rotating Vessel Services. Our services include the installation of a new plant, rebuilds, and the planning, scheduling, and consulting for shutdowns and major works on all types of rotary vessels including kilns, dryers, coolers, calciners, ball mills and rod mills.

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Mechanical condition inspections and reports with recommendations for rectifying identified problems are also offered. Our precision onsite and offsite services coupled with our flexibility towards customers’ unique needs allow for significant reductions in equipment downtime.

  HOT KILN ALIGNMENT  

The majority of problems associated with rotary kilns and vessels can be attributed to misalignment. As such, comprehensive hot kiln alignment significantly contributes towards rotary kilns’ and vessels’ ability to achieve maximum efficiency throughout their service life, whilst eliminating unforeseen breakdowns.

Our Hot Kiln Alignment Services in association with our Routine Inspection Services are tailored to increase plant availability, reduce maintenance-related costs and provide more optimal plant efficiency. Some of the consequences of not timeously doing routine or planned alignment are summarised below:

  • Plant operating outside optimal conditions

  • Excessive and unnecessary forces on the vessel/kiln shell

  • Metal fatigue and cracking of tyre and shell

  • Deformation of vessel/kiln

  • Excessive stress on tyres and rollers

  • Undue wear on tyres and rollers

  • Unnecessary loads on the drive mechanism

  • Damage to end seals

  • Premature bearing failure

  • Frequent premature failure on the refractory lining

DGC AFRICA has established a strategic alliance with GEOSERVEX (Poland), for the past 40 years the world leader in the development and implementation of the technology of kiln alignment in dynamic conditions (during normal operation). Geoservex are pioneers of the hot kiln alignment method and a worldwide leader of this service in the global market.

Kiln alignment has to be carried out during the normal operation of the kiln in order to obtain the most realistic information and data on the condition of the kiln without disturbing the clinker production. As a part of preventative maintenance, kiln alignment identifies the actual cause of problems and provides recommendations for appropriate solutions.

Our alignment approach is based on advanced measuring techniques and customised hardware and software. It is evaluated by experienced alignment specialists. Based on our experience and considering major root causes to all kiln failures, our alignment method aims to improve and ensure kiln availability by optimization of Kiln Axis, Kiln Shell Ovality, Kiln Crank and Kiln Axial Balance. The detailed scope of services is as follows:

  KILN    AXIS  

  • Measurement of kiln axis position in the horizontal and vertical plane by using advanced survey methods.

  • Measurement and calculation of tyre and supporting rollers diameter by using a special electronic instrument.

  • Measurement of base frame foundation settlement.

  • Preparation of optimal version of support roller adjustment program and schedule.

  KILN    SHELL OVALITY  

  • Kiln shell ovality test at all supports (direct survey of elastic deformation of the kiln shell).

  • Measurement of tyre migration and calculation of under-tyre clearance.

  KILN    CRANK  

  • Measurement of supporting rollers and shaft cyclical deflection.

  • Measurement of tyres wobbling.

  • Measurement of kiln shell profile at all shell sections.

  • Measurement of kiln shell permanent deformations.

  • Preparation of shell animation model (unique full 3D rotating shell). 

  • Measurement of kiln shell temperatures distribution (indication of shell temperature crank).

  KILN    AXIAL BALANCE  

  • Measurement of supporting rollers axis position, rollers skewing and operating angle.

  • Measurement of supporting rollers inclination and base frame axial slope.

  • Measurement of supporting rollers profiles (mechanical wear of running surface).

  • Evaluation of kiln thrust and mechanical balance. 

  SUPPLEMENTARY    MEASUREMENTS  

  • Measurement of girth gear wobbling.

  • Measurement of thrust rollers position in reference to the kiln axis.

  • Checking kiln drive alignment (option – the kiln must be stopped for a few hours due to safety reasons).

  • General mechanical inspection of drive mesh, support roller bearings and shaft condition, lubrication efficiency, inlet and outlet sealing, thrust unit, adjustment equipment, covers and housing.  

  COMPREHENSIVE    KILN INSPECTION  

Additional data are required from the plant to do an engineering study of the kiln. The following results have to be given by doing a comprehensive kiln inspection. 

  • Current loads on piers.

  • Pressure on bearings.

  • Hertz pressures on roller-tyre contact.

  • Bending stress in the kiln shell.

  • Stress in the tyres.

  • Stiffness matrix, optimization of kiln vertical axis position considering load distribution.

  • Preparation and submission of the completed report including results of a survey, short- and long-term recommendations for preventive maintenance actions.

  ADVANTAGES OF DOING  

  GEOSERVEX HKA METHOD  

  • After completion of kiln axis correction, we do cross-check of kiln axis measurement.

  • Diameter measurement and calculation of tyre and support roller by using electronic instrument.

  • Surface wear profile measurement of support roller at 4-5 locations.

  • Measurement of support roller axis position and roller skewing.

  • Measurement of roller operating angle.

  • Kiln shell animation model and submitting in pdf format (unique full 3D rotating shell).

  • Calculation of under tyre clearance.

  • Measurement of axial deviation on drive station (Pinion to Gearbox).

  • Measurement of thrust roller position with respect to kiln axis.

  • All the measured readings and their results are very high accuracy and manual error can be eliminated by using advanced survey instruments with software.

  • Output data can be cross-check and evaluated by calculations.

  BENEFITS OF DOING HKA  

  ONCE IN 2 YEARS  

  • Prevention against uneven load on supports.

  • Higher equipment availability and longer kiln life.

  • Elimination of excess longitudinal stress in the shell, no more cracks of the shell.

  • Elimination of high thrust forces for rollers, tyres side guidance, and thrust rollers.

  • Elimination of hot bearings and hot thrust collars.

  • Prevention against refractory loss and excess of ovality.

  • Reduction of heavy torque for kiln drive coming from misalignment and unbalanced opposite thrust forces.

  FINAL    REPORT  

When Hot Kiln Alignment has been carried out, our specialists provide a final comprehensive technical evaluation and analysis report, as well as recommendations for adjustments, repairs, spare parts, and optimizations.

 

The report is an essential document to help production and maintenance departments plan future maintenance activities, such as ensuring that the right spare parts are available and, most importantly, avoiding unscheduled, costly shutdowns.

 

The following information will be available in our detailed report for the high availability of rotary kilns and rotating vessels:

  • Actions to be taken as soon as possible.

  • Actions to be taken during the next kiln shutdown.

  • Actions to be taken for future activities.

  DOWNLOADS    

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  SUPERVISION & TROUBLE SHOOTING SERVICES  

DGC AFRICA is well placed with specialists who can deal with most of the key mining, cement, steel, and fertilizer plant’s rotary kilns and rotating vessels. 

 

We can provide technical guidance and assistance for troubleshooting, overhaul, repair, maintenance, and operation of ATOX VRM, Grate Coolers, Kiln, and Ball Mills.

 

If you have a problem in your kiln, mill, high vibrations in mill/kill drive, problem in grate coolers, or would like to undertake mechanical repairs during your shutdown, you may consult us and employ our trouble-free supervision services.

  OUR SPECIALIZATION    

We are specialists in the following jobs:

  KILN    

  • Shell Replacement

  • Tyre Replacement

  • Supporting Roller/Bearing Replacement

  • Girth Gear and Pinion Reversal/Replacement

  • Thrust Roller Replacement

  • Inlet/Outlet Seal Replacement

  • Supporting Roller Adjustments for Thrust Correction (during operation)

  • Solving of Hot Bearing Issue (during operation)

  • Vibration at Kiln Drive Station (during operation)

  BALL    MILL  

  • Replacement of Trunnion/Slide Shoe Bearings

  • Replacement of Mill Head with Trunnion

  • Reversal/Replacement of Mill Girth Gear/Pinion

  • Replacement of Inlet/Outlet Cones

  • Replacement of Mill Diaphragm/Liners etc.

  ATOX    MILL  

  • Grinding Rollers Overhauling (Bearing Replacement)

  • Replacement of Joint Head/Torque Arm

  • Replacement of Pull Rod Arrangements

  • Table/Roller Wear Segment Replacement

  GRATE    COOLER  

  • Cooler Main Beam Replacement

  • Cooler Stationary/Movable Beam Replacement

  • Grate Plates Replacement

  • Cooler Alignment

  KEY    BENEFITS  

  • Performed during both normal operation and standstill of the equipment.

  • Minimize downtime.

  • Commissioning the equipment with full load operation.

  • Performed by high experienced DGC AFRICA and Geoservex specialists.

  • Recommendations for future improvements.

  FINAL    REPORT  

When supervision and troubleshooting services are carried out by DGC AFRICA, our specialist will provide all service protocols related to the jobs performed as well as the recommendations for spare parts.

 

The service protocols are an essential document to ensure the equipment was installed within the allowed limit or not, and root causes for the same if not achieved. Also, this document helps the maintenance department to track activities performed on particular equipment while doing troubleshooting services.

  FIELD SERVICES  

We offer Machining, Repair and or Modification services in respect to machinery used in a range of industries such as Earthmoving, Mining, Marine, Transport and Agricultural Machinery and Systems including:

  • Modern Line Boring machines are capable of welding and boring in the field and are available at short notice supplied with or without an operator.

  • Flange facing options include Ring Type Joint and Raised Face Flanges for a large range of sizes supplied with or without an operator.

  • Pipe cutting and bevelling machines are simple to operate and available in multiple sizes to suit your specific circumstances supplied with or without an operator.

  • Portable Shaft Lathes give the ability to repair damaged shafts on heavy equipment in the field to minimize both downtime and costs.

  • Either gantry [3 axes] or linear [2 axes] style milling machines available to suit your circumstances supplied with or without an operator. Suitable for resurfacing of Motor and Pump Bases, Machine Track Pads, and many other machine surfaces including vertical or inclined faces. We also offer onsite welding of pads to enable machining back to original specifications.

  • Tyre & roller grinding helps maintain surface contact minimizing wear and power usage.

  RESURFACING OF TYRE 

  & SUPPORTING ROLLERS  

DGC AFRICA provides Resurfacing of Tyre & Supporting Rollers (RTAR) services for all our esteemed rotary kiln and rotary vessel customers. We have specifically designed machines to accommodate and be suitable for various OEMs of rotating vessels including different dimensions of tyre and rollers. All work is completed by experienced DGC AFRICA Grinding specialists.

 

When DGC AFRICA conducts in-situ grinding of tyre and support rollers, no kiln downtime is needed and our company employs internationally trained grinding engineers to undertake the work. Our grinding engineers constantly monitor axial thrust and bearing temperature throughout the grinding process, carrying out roller adjustments that were required to stabilize axial movement and temperature.

 

Our company utilizes state-of-the-art portable belt grinding SM 400 Kiln Tyre Grinding Machine and SMF 1000 Kiln Rollers Grinding Machine, from Vetroresina Engineering Development S.r.l. Italy, which is built for heavy-duty applications.

  WHY RESURFACING    (RTAR)? 

Rotary kilns, dryers, and similar types of rotary equipment stay in continual operation most of the year and as time goes by, various types of wear problems occur. RTAR and roller naturally form irregular surface profiles due to improper skewing of rollers and in addition to pitting due to dust, spalling, irregular markings, and rolled-over edges.

  MAINTAIN AND IMPROVE  

  THE MECHANICAL STABILITY OF ROTARY KILN/DRYERS 

CONSEQUENCES IF NOT PERFORMING RTAR

  • Vibrations at the supports

  • Inability to control axial balancing of kiln, misalignment

  • Premature bearing failure

  • Increased main drive power consumption

  • Damage to tyre retaining components, and

  • Damage to support bases, and drive components.

  DGC AFRICA RTAR    SERVICES 

Our kiln specialist can control the behaviour of the kiln and rotary equipment during the Resurfacing process:

  • Resurfacing removes work hardening and minimizes the damage of fresh surfaces.

  • Resurfacing of tyre thrust face and thrust roller, to remove the waviness over the thrust face and also to remove the flat marks, step over the thrust roller top and bottomland and tyre thrust face while kiln in operation.

  • Resurfacing changes the thrust characteristics of the support rollers and allow free travel of the roller in the support bearings.

  • These changes are continuously monitored during the process and adjustments are made to control the position of the kiln/rotary equipment.

  • Geoservex specialists accurately measure and report the diameter before and after the resurfacing and necessary support rollers adjustment has to be carryout without disturbing the kiln production.

  BENEFITS OF RESURFACING  

  OF TYRE & SUPPORTING ROLLERS  

  • Reduce the power consumption of the drive station.

  • Improves the mechanical stability of rotary kiln and rotating equipment.

  • Improve the contact between tyre and rollers.

  • Eliminate vibration at the supports.

  • Reduces zero downtime.

  • Support roller adjustment for skew correction.

  • Improves the axial balancing of kiln.

  • Plant operation is uninterrupted.

  • Minimize the operating cost.

  • Prolong service life.

  CAPITAL REPAIR PROJECTS  

DGC AFRICA delivers a production-focused approach to Capital Repair Projects where we can perform any type of maintenance, repair, or installation services in the shortest possible safe completion times and to OEM standards.

 

We have an experienced field service team to assist with your company's scheduled or emergency maintenance shutdown in order to limit production loss. We can perform any type of maintenance, repair, or installation services to process equipment including:

  • New Kiln and Mill Installations

  • Kiln Shell Section Replacement

  • Kiln Tyre/Supporting Roller Replacement

  • Kiln Girth Gear/Pinion Reversal/Replacement

  • Kiln Thrust Roller Replacement

  • Vertical & Ball Mill Overhaul

  • Ball Mill Inlet/Outlet Shell Replacement

  • Ball Mill Inlet/Outlet Head Replacement

  • Ball Mill Head with Flange Reaming

  • Ball Mill Girth Gear/Pinion Reversal/Replacement

  • Ball Mill Trunnion/Slide Shoe Bearing Replacement

  • Grate Cooler Alignment and Overhauling

  • Drive Machinery Replacement and/or Alignment

  • Trunnion Roller Replacement or Overhaul

  • Support Base Replacement or Machining

  • Kiln Inlet/Outlet Seal Replacement

  • Shell Crack Repairs & Replacement

  • Tyre Crack Repairs & Replacement

  • Slew Bearing Installation or Replacement

  • Crusher Overhauls

  • Apron Feeder Overhaul

  KEY    BENEFITS  

  • Minimize the shutdown and complete the project within the given timeframe.

  • The highest quality of the project works with tolerance limits for the reliability and availability of the equipment.

  • Round the clock 24/7 supervision by experienced DGC AFRICA and Geoservex specialists for spot decision making and ensuring the successful execution of the project, ensuring on-time completion.

  • Executed by highly experienced DGC AFRICA and Geoservex specialists and well-qualified and experienced technicians.

  • DGC AFRICA has been proven to maintain very high safety standards for our engineers and workmen and also depute one safety supervisors exclusively to oversee the safety aspects of the project to ensure zero accidents.

  • Daily progress of the project will be updated to our customers to ensure that immediate action can be taken to mitigate the slow progress of the works if any.

  • Commissioning the equipment with full load operation.

  • Our company only utilises certified tools and tackles which have been maintained to a high standard.

  • High availability of our equipment.

  PRO-ACTIVE    ON SAFETY  

We depute qualified safety supervisors along with our specialist site personnel to ensure round the clock safe action, methods and behaviour. Our teamwork nurtures a safe work environment for our employees and subcontractor’s workmen the same we ensure to strictly follow. We are committed to continue doing our best by making safety a mandatory requirement for all our employees and subcontractors workmen. Furthermore, all our tools and equipment are certified by recognized agencies and we provide mandatory safety training to all our engineers.

  BALL MILL SERVICES  

DGC AFRICA in conjunction with GEOSERVEX are well experienced in the various design of OEM makes ball mills in order to evaluate the condition of the ball mill. An inspection to be executed by our Mill specialists with in-depth knowledge of complete mill components for ensuring optimal, trouble-free operation.

  CONDITION INSPECTION  

  (DURING STATIC)  

To get a detailed picture of the mill’s overall condition, including parts that need to be replaced, it is important to carry out an external and internal inspection when the mill is not in operation.

  NDT    ANALYSIS  

  • Checking the thickness of the Trunnion journal.

  • Mill shell thickness.

  • Ultrasonic Testing (UT) of Trunnion journal.

  • Ultrasonic Testing (UT) of all welding joints.

  • Ultrasonic Testing (UT) of all T joints.

  • Magnetic Particle Inspection (MPI) of Girth and Pinion.

  • Magnetic Particle Inspection (MPI) of Mill manhole door.

  • Magnetic Particle Inspection (MPI) of Trunnion neck area.

  INSPECTION    & MEASUREMENT  

  • Mill Trunnion radial run out.

  • Mill lifting at inlet/outlet.

  • Mill slide ring radial run out.

  • Measurement of Girth Gear axial and radial run-out.

  • Measurement of root gap and backlash of gear and pinion.

  • Inspection of the Trunnion lubrication unit.

  • Visual inspection of Mill components.

  KEY    BENEFITS  

  • Minimize downtime.

  • Optimize the Mill availability.

  • Performed during operation or standstill of the Mill.

  • Uninterrupted production.

  • Executed by highly experienced Geoservex Mill specialist.

  • Final presentation and sharing of knowledge with plant personnel.

  • Recommendations for future improvements.   

When inspections of mill components have been carried out, our specialists provide a final comprehensive technical evaluation and analysis report, as well as recommendations for repairs, spare parts, adjustments, and optimizations.

The report is an essential document to help production and maintenance departments plan future maintenance activities, such as ensuring that the right spare parts are available, and – most importantly – avoid unscheduled, costly shutdowns.

  PARTS & EQUIPMENT  

At some point, regardless of how well your kiln has been maintained throughout its life, expensive parts like girth gear, rollers, kiln shell sections, etc. will need to be replaced or repaired.  We help you find the most cost-effective solution and scheduling to perform the works.

 

We can supply new machinery and equipment or spare parts to suit your existing machinery including;

  • New Kilns, Calciners, Dryers or Coolers

  • Replacement Kiln Tyres & Shell Sections

  • New Mills & Mill Parts

  • Kiln Seal Assemblies or Parts

  • Trunnion Rollers & Bearings

  • Girth Gears & Pinions & Associated Parts

  • Slew Bearings & Specialised Bearing

  • Gearboxes & Parts

  • Mining Machinery