Manual para ingenieros mecanicos


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Manual para ingenieros mecanicos

  1. 1. ContiTech Specialist in Rubber TechnologyEditionConveyor BeltingManual forMechanical EngineersContinental Aktiengesellschaft 1
  2. 2. ContiTech Specialist in Rubber Technology CONTI® Conveyor Belting ContiTech manufactures Conveyor Belting for all branches of industry and for a wide range of applications. The product range comprises Textile-Ply and Steel Cable Conveyor Belts, as well as Special-Purpose Conveyor Belts and a versatile range of accessories. CONTI Conveyor Belt Edition ContiTech issues a series of informative Conveyor Belt publications on the subject of conveyor system engineering. Brochures published to date contain a wealth of general and product-specific information, guidance on conveyor belt installation and repair, technical data for conveyor system design and application engineering, plus details on available accessories and belt types. Other topics are currently in preparation. Conveyor Belting Manual for Mechanical Engineers This brochure is the first time concise documentation has been compiled covering all aspects of a mechanical engineers working environment. A thorough understanding and careful monitoring of the system are essential to ensure reliable operation of a conveyor belt line. Invaluable information is provided on the structure of a conveyor belt, preparing the site for belt installation, commissioning, operation, maintenance, repair and seasonal system shutdown. ContiTech Advanced technology in rubber processing and manufacture Worldwide application Latest technology in production and development 3
  3. 3. Responsibilities of the mechanical engineer Planning Ordering InstallationConti offers Conti offers Conti offersProduct information Quality Engineers who provide expert adviceComputer service Punctual order-servicingSystem design data Site delivery Comprehensive rangeTechnical advice Packaging Your advantages areProject studies Pre-shipment release Your advantages areProblem analysis through a neutral body of Recommendations forResearch and development quality assurance optimum belt installationStandardization engineers time and cost-saving conformity with agreedYour advantages are grades of quality Coordination of delivery direct delivery of belt Decision-making aids Monitoring of project to site; protection from the right choice of belt schedules damage during smooth timing transportation Low-cost design optimum economy Effective standartization less stock required Smooth and clean operation of the conveyor system minimal maintenace
  4. 4. Splicing Comissioning InspectionConti offers Conti offers Conti offersOptimized splicing systems Belt approval Belt inspectionsSplicing materials Troubleshooting guidance Repair serviceVulcanization Expert on-site advice Instruction and training of vulcanizers andFundamental research maintenance staff Your advantages areYour advantages are Localization and elemination of trouble Your advantages are Splicing materials spots Expert opinions and specially developed for limitation of damage reports each belt type risk minimizing of overall risk optimum strength at splice Belt commissioning Assessment of the belt`s without problems condition Provision of latest minimum delay in systematic repairs vulcanizing equipment starting conveyor service uniform curing Repair materials to suit each type of belt Own fitters optimum service life excellent knowledge of materials and belts Trained maintenance staff low-cost repairs
  5. 5. ContiTech Specialist in Rubber Technology Quality assurance Advisory service at ContiTech at ContiTech ® CONTI Conveyor Belting and CONTIs Application Engineers Conveyor Belting Accessories are assist in determining the technically state-of-the-art products in every and economically most suitable type aspect of material specification and of CONTI product for the specific product design. This is guaranteed application. Backed by the R & D by Continentals in-house quality division of ContiTech, our consultants assurance experts. All CONTI are able to provide not only the products undergo rigid, independent optimum solution but one precisely quality controls throughout and after tailored to end-product service manufacturing to ensure uniformity requirements. and a constant high standard of technical excellence.
  6. 6. ContiTech Specialist in Rubber TechnologyConveyor Belt ServiceConveyor BeltingManual forMechanical EngineersEdited byDr.-Ing. R. AllesDipl.-Ing. G. BöttcherObering. W. ErnstPublished byContinental Aktiengesellschaft, Hannover, Germany2nd Edition 1990
  7. 7. 1 Structure and identification 5 Commissioning _____________ 32 of conveyor belts _____________ 2 5.1 Tensionieng the belt_________________ 32 1.1 Tension members ____________________ 2 5.2 Starting the belt_____________________ 321.1.1 Conveyor belts with textile plies _________ 2 5.3 Training the belt ____________________ 331.1.2 Steel cable conveyor belts _____________ 5 1.2 Covers _____________________________ 6 6 Operation and problem solving _ 401.2.1 Cover thickness______________________ 6 6.1 Daily inspection of the conveyor belt;1.2.2 Cover grade ________________________ 6 causes of belt damage _______________ 401.2.3 Cover reinforcement __________________ 8 6.2 Dai!y inspection of the system__________ 421.2.4 Cover patterns ______________________ 8 7 Maintenance and repair _______ 44 2 Ordering and storing _________ 12 7.1 Repair materials ____________________ 44 2.1 How to order conveyor belts ___________ 12 7.2 Repairing damage with ®2.1.1 Example of how to order______________ 12 CONREMA repair materials___________ 462.1.2 Delivery of endless belts _____________ 12 7.2.1 Repairing damaged covers ___________ 46 2.2 Delivery and storage _________________ 13 7.2.2 Repairing penetrations and damage2.2.1 Packaging _________________________ 13 to the fabric________________________ 48 Technical data for textile tension members __________________________ 13 8 Seasonal shutdown and Diagrams showing different roll winter operation _____________ 54 diameters ______________________ 14-172.2.2 Storage ___________________________ 18 Index _________________________ 56 3 Preparations for installation ___ 20 3.1 Preparing the structure _______________ 20 Drive pulley ________________________ 20 Conveyor belt systems - Take-up station _____________________ 21 Troubleshooting guide Idlers and idler sets __________________ 21 (Supplement) Scrapers __________________________ 21 Loading and transfer chutes ___________ 22 ® CORREX abrasion resistant material ____ 22 3.2 Preparations for pulling the belt onto the structure _______________________ 233.2.1 Hanging the belt roll in let-off stands ____ 233.2.2 Pulling in the belt ___________________ 23 4 Splicing conveyor belts ______ 26 4.1 Splicing fabric-ply conveyor belts _______ 264.1.1 Mechanical splices (detachable) _______ 264.1.2 Vulcanized splices (non detachable) ____ 26 4.2 Splicing steel cable conveyor belts ______ 29
  8. 8. ContiTech Specialist in Rubber Technology 1 1.1 Tension membersStructure and 1.2 Coversidentificationof conveyor beltsAerial cableway is replacedby a belt conveyor
  9. 9. 1 Structure and identification of conveyor belts Structure and identification of conveyor belts Dimensions, test values, designations, etc. of conveyor belts are specified in the following standards: DIN 22101 Belt conveyors for bulk materials DIN 22102 Conveyor belts with textile plies DIN 22103 Flame resistant conveyor belts DIN 22104 Antistatic conveyor belts DIN 22109 Textile-ply conveyor belts for coal mining DIN 22131 Steel cable conveyor belts DIN 22129 Steel cable conveyor belts for underground coal mining (draft) Ordering and delivery of conveyor belts are based on specifications given in the above standards. Any dimensions or other requirements deviating from the corresponding standard are subject to special agreement with the manufacturer. 1.1 Tension members Conveyor belts are reinforced with one or more plies of special textile fabric or one layer of adjacent steel cables. The following code letters denote the type of material used as reinforcement. B cotton Z high-strength viscose staple fibre R high-strength rayon P polyamide (trade names such as "Nylon", "Perlon") E polyester (trade names such as "Trevira", "Diolen") D aramide (trade names such as "Kevlar”, "Arenka") St steel cables 1.1.1 Conveyor belts with textile plies In virtually all cases, square-woven fabric of various kinds of weave is used for conveyor belts. The terms "warp" (running parallel to the length of the cloth) and "weft" (running across the width of the cloth) have been taken over from the weaving process. During the years of pioneering belt development, only cotton was used as a textile material. The advancement to fully synthetic fibres brought with it the manufacture of new high-strength types of fabric, leading to a decisive change and improvement in the structure and performance of conveyor belts. Polyester: Fully synthetic, high strength with low elongation, high workload capacity, largely resistant to acids and alkalis, unaffected by moisture (at normal temperatures). Polyamide: Fully synthetic, high tear resistance, high elongation, rotproof, resistant to moisture and chemicals. Aramide; Fully synthetic, highly aromatic polyamide fibre with extra high strength and low elongation; has the advantages of all fully synthetic fibres, is flame- resistant without undergoing special treatment and is gaining significance in the manufacture of high-strength textile-ply belts.2
  10. 10. Structure and identification of conveyor belts 1Whereas earlier types of conveyor belt used to be reinforced with a"purebred" fabric, specialists in textile technology have since developedfabrics with combinations of different materials. Depending on the physicalproperties of the warp and weft, these mixed fabrics give the belt the rightproperties to meet specific in-service requirements. Textile plies areidentified by two capital letters.The first letter shows the material used inwarp direction and the second letter shows that used in weft direction.e.g. EP (warp: polyester/weft: polyamide)Good properties fort he warp are:High strength, low permanent elongation, hence short take-ups. Strengthand elongation even remain unaffected by wet conditions, rotproof.Good properties for the weft are:High elastic elongation, hence good troughability and large filling crosssection, good workload capacity and therefore a good resistance tomechanical destruction.In addition, brief reference should also be made at this point to the types offabric commonly used for mining service:e.g. Pb (the second letter is small)This coding means that two different kinds of material have been twistedtogether to form one thread. The capital letter stands for the material givingthe highest measure of strength.Following the material code is the strength grading in figures according toDIN 22102 standard specifications. The strength of the textile fabric and thatof the entire belt are stated in N/mm width (previously kg/cm width).Strength values comply with the R10 standardized series of numberscontained in DIN 323, i.e. 160, 200, 250, 315, 400, 500, 630, 800,1000,1250,1600, 2000, 2500, 3150, 4000, 5000, 6300.Identification coding of a conveyor belt could for instance read as follows: EP = type of fabric /1000 = overall strength in N/mm belt width / 4 = number of pliesi.e. the belts tension member with a strength of 1000 N/mm belt widthconsists of 4 plies of polyester/polyamide textile fabric, EP 250.The high strength and ability of fully synthetic blended fabric to withstandhigh dynamic stressing enabled the number of plies to be reduced. This ledto the following generation of belts made by Continental: ®1-ply belts (only for underground) CON-MONTEX ®2-ply belts CON-BITEXMulti-ply belts 3
  11. 11. 1 Structure and identification of conveyor beltsTechnical Data (guide values)Type Nominal Elongation at Thickness of Tension Elastic Minimum Minimum belt strength at break (longit.) tension member mass elongation up pulley width at 30° splice member (w/o cover to 10% of mini- diameter (drive troughing angle (belt core) M or N) mum breaking pulley) strength (longit.) in N/mm in % in mm in kg/m2 in% in mm in mm2-ply belts (with thick intermediate rubber layer)CON- 200/2 200 12-16 3.5 3.9 0.6 - 1.2 250 400 ®BITEX 250/2 250 3.7 4.1 315 400 315/2 315 3.9 4.3 315 400 400/2 400 4.1 4.6 400 400 500/2 500 4.7 4.8 400 500 630/2 630 5.2 6.1 500 500 800/2 800 6.3 6.4 500 650 1000/2 1000 7.1 7.9 630 800 1250/2 1250 7.7 8.8 800 10002-ply beltsCON- 200/2 100 12-16 1.8 1.9 0.6 - 1.2 200 400MULTEX 250/2 125 2.0 2.3 250 400 315/2 160 2.2 2.4 250 400 400/2 200 2.6 2.8 315 400 500/2 250 3.2 3.2 400 500 630/2 315 3.8 4.2 500 500 800/2 400 4.8 4.8 630 650 1000/2 500 5.8 5.9 630 800 1250/2 630 6.2 6.5 800 8003-ply beltsCON- 315/3 200 12-16 2.7 2.8 0.6 - 1.2 315 400MULTEX 400/3 250 3.0 3.4 315 400 500/3 315 3.3 3.7 400 500 630/3 400 3.9 4.2 500 500 800/3 500 4.8 4.8 500 650 1000/3 630 5.7 6.4 630 800 1250/3 800 7.2 7.2 800 8004-ply beltsCON- 400/4 315 12-16 3.2 3.8 0.6 - 1.2 400 400MULTEX 500/4 400 4.0 4.5 500 500 630/4 500 4.4 4.9 500 500 800/4 630 5.2 5.6 630 650 1000/4 800 6.4 6.4 800 800 1250/4 1000 7.6 8.5 800 1000 1600/4 1250 9.6 9.6 1000 10005-ply beltsCON- 500/5 400 12-16 4.0 4.7 0.6 - 1.2 500 500MULTEX 630/5 500 5.0 5.7 630 500 800/5 630 5.5 6.1 630 650 1000/5 800 6.5 7.0 800 800 1250/5 1000 8.0 8.0 1000 1000 1600/5 1250 9.5 10.6 1000 1200 2000/5 1600 12.0 12.0 1250 1200 Other types of belt available on request4
  12. 12. Aufbau und Kennzeichnung der Fördergurte 1 1.1.2 Steel cable conveyor belts All ContiTech Steel Cable Conveyor Belts bear the registered trade name ® of STAHLCORD . Reinforcement for steel cable conveyor belts is in the form of one ply of high-tensile steel cables embedded in rubber and arranged in one plane ® running parallel to each other longitudinally. STAHLCORD Conveyor Belts are ideally suited to long-distance conveyors due to the high breaking strength of the steel cables. The belt construction itself plus the high-tensile ® steel cables enclosed on all sides by rubber provide STAHLCORD Conveyor Belts with a high resistance to impact damage at conveyor feed points, even when handling large lump-size material and where large drop ® heights are concerned. STAHLCORD Conveyor Belts also have a good troughability. Identification and dimensions are specified in DIN 22131 (Standard DIN 22129 "Steel cable belts for underground coal mining" is available in draft version). Coding for the tension member is made up as follows: St = steel cables / 2000 = overall strength in N/mm belt width Since only one layer of steel cables is embedded in the rubber according to DIN 22131, the figure after the oblique which appears in the coding reference for textile-ply belts does not apply in this case. Strengths of steel cable conveyor belts currently range from 500 N/mm to 7300 N/mm. The strength of the belt is determined by the strength of the steel cables and their spacing (pitch). Grades of strength specified in DIN 22 131 are supplemented by special versions according to the R 20 series.Technical Data (guide values) Type Nominal Pitch Thickness of Tension member mass Minimum Minimum strength tension (belt core) without covers pulley cover at splice member diameter thickness (belt core) (M or N) (V) (drive pulley) in N/mm in mm in mm in kg/m2 in kg/m2 in mm in mm St 500 500 12.5 2.8 5.3 6.4 500 3 St 630 630 10 2.8 5.8 6.8 500 3 St 800 800 12 3.6 7.4 8.8 630 3 St 1000 1000 12 4.0 8.9 10.4 630 3 St 1250 1250 14 4.7 10.6 12.3 630 3 St 1400 1400 9 4.0 10.3 11.6 630 3 St 1600 1600 15 5.5 12.8 14.7 800 4 St 1800 1800 13.5 5.5 13.5 15.4 800 4 St 2000 2000 12 5.5 14.3 16.2 800 4 St 2250 2250 11 5.5 15.0 16.8 800 4 St 2500 2500 15 7.0 18.0 20.3 1000 5 St 2800 2800 13.5 7.0 19.0 21.3 1000 5 St 3150 3150 15 7.8 22.0 24.5 1250 5.5 1 St 3500 3500 ) 15 8.2 23.6 26.3 1250 5.5 1 St 4000 4000 ) 15 8.8 26.6 29.4 1250 6.5 1 St 4500 4500 ) 16 9.6 29.0 32.1 1400 7 1 St 5000 5000 ) 17 10.7 33.0 36.3 1600 7.5 1 St 5400 5600 ) 17 11.7 36.2 39.9 1600 8 1 St 6300 6300 ) 18 12.2 40.4 44.0 1600 8.5 1 St 7300 7300 ) 19 13.1 43.9 47.7 1800 9 51) without allowances according to DIN 22101
  13. 13. 1 Structure and identification of conveyor belts 1.2 Covers If the reinforcement of a conveyor belt is to retain its strength, it must be given ample protection from mechanical damage and rotting. The tension member is therefore provided with a cover on the top or conveying side of the belt and also on the bottom side. 1.2.1 Cover thickness Cover thicknesses are generally determined by the anticipated amount of wear caused by the conveyed material and measure between 0.5 and 20.0 mm. A somewhat thinner bottom cover can be selected in most cases but the ratio of top to bottom cover thickness should not exceed about 3:1 (cf. DIN 22101). Great differences between the two cover thicknesses can lead to undesired tensions within the belt and bulging of its edges due to shrinkage of the rubber following vulcanization. Minimum cover thicknesses are prescribed for steel cable conveyor belts (DIN 22101). Special attention when selecting the cover thicknesses can also optimize the lateral rigidity required for some applications. 1.2.2 Cover grade It is easy to realize the different types of stressing a conveyor belt is subjected to when we consider the vast range of materials to be conveyed - literally anything from coal to foodstuffs. Similarly, the number of different cover grades to choose from is high. Basic qualities and main properties of a cover are specified in correspond- ing DIN standards and are distinguished by the letters shown below: Code letters Property Steel cable belts Fabric-ply belts (DIN 22 131) (DIN 22 102) flame resistant F antistatic E flame resistant und antistatic* K S self-extinguishing and antistatic* (DIN 22 131) V (DIN 22 109) resistant to elevated temperatures T resistant to low temperatures R resistant to oil and grease G belts for foofstuffs A belts for chemical products C belts with fixed mechanical M, N M, N, P, Q parameters special grades X * (Belt cover grades for coal mining service are subject to special conditions of approval issued by the German mines authorities.) It is quite possible that several of these properties have to be fulfilled by one belt, e.g. in the handling of freshly baked bread or confectionary, the cover may have to be white and resistant to oil and grease as well as higher temperatures. When ordering it is therefore extremely important to give a precise definition of the material to be conveyed and its characteristics.6
  14. 14. Structure and identification of conveyor belts 1Properties of the most popular ContiTech cover grades (guide values)DIN Continental Density Suitable for Permissible temperature** Resistant Tension Colour PolymerCode equivalent p in °C to oil and member constant peak grease kg/dm3 min. max. min. max.M ATRB 1.09 general conveying -50 +60 -55 +70 no any black NR (maximum type requirements)N CONTINENTAL 1.13 general conveying -30 +60 -35 +70 no any black NR/ EXTRA type SBR ®X CONTI-CLEAN 1.12 heavy soiling -50 +60 -55 +70 no any black BR/NR (dirt repelled) (with high moisture type content)N, K FH 1.24 machine belts in -30 +60 -35 +70 no any black NR/BR (flame retardant) open cast mines typeS, K FW (flame 1.38 underground and -30 +60 -35 +70 no any black SBR resistant) surface typeV V 1.42 underground - +100 - +110 within fabric black CR (self- 1.60 mining (maximum limits steel extinguishing) safety requirements) ®S, T VULKAN 1.39 hot materials -30 +110 -30 +130 within any black CR spezial with glowing limits type (flame resistant) embers ®T VULKAN - 1.13 hot materials -30 +110 -40 +130 no any black SBR T 130 type ®T VULKAN 1.13 hot materials -30 +130 -40 +150 no any black SBR extra-T150 type ®T, C* VULKAN 1.13 hot materials, -30 +160 -40 +180 no fabric black IIR super - T 180 also resistant to only acids and alkalisG TDAX 1.17 oily, greasy -10 +70 -20 +90 yes fabric black NBR materials onlyG TBBX 1.13 oil sand -50 +60 -50 +70 yes any black NBR typeA TDLX 1.21 foodstuffs (oily, -10 +120 -15 +140 yes fabric white NBR greasy and hot) onlyX, C* TOWN 1.0 materials with acid -40 +60 -45 +70 no fabric grey NR content onlyE TBBN 1.25 potentially -30 +60 -35 +70 no any black NR (electrically explosive type conductive) materialsV PVC (self- 1.35 underground -5 +50 -5 +60 yes fabric brown PVC extinguishing) only* For applications involving potential chemical attack, we recommend prior consultationwith our Application Engineers.** These temperature specifications refer to the conveyor belt; maximum temperature loads areHowever also subject to the nature of exposure to these temperatures (see also German RubberManufacturers` Association guidelines No. 339).Details of other cover grades and specifications given on request. 7
  15. 15. 1 Structure and identification of conveyor belts 1.2.3 Cover reinforcement To protect the tension member and give added resistance to impacts, the cover can be provided with additional transverse reinforcement made of textile cord or steel strands. This increases the belts resistance to penetra- tion and reduces the danger of longitudinal slitting. Transverse reinforcement of the covers Type Transverse Arrangement Tension member reinforcement ® CONTI-CROSS textile cord one side STAHLCORD T (polyamide) (top or bottom) (all types) ® CONTI-CROSS textile cord both sides STAHLCORD T/T (polyamide) (all types) ® CONTI-CROSS Steel strands both sides STAHLCORD S/S special-purpose types Breaker fabric one side fabric-ply belts (polyamide) (top) or both sides 1.2.4 Cover patterns To ensure optimum transport of special materials, e.g. on luggage and parcel conveyors, industrial assembly and sorting conveyors, or when conveying at a certain gradient, it may be necessary to provide the belt cover with a pattern. The most popular patterns to improve holding or eliminate rollback of materials can be seen below. Coarse cloth impression Transverse ribbing Coarse duck impression Transverse multi-cleats Herringbone pattern Longitudinal multi-cleats8
  16. 16. Structure and identification of conveyor belts 1The Steep-Angle Conveyor Belt with 15 mm high chevron cleats on the topcover is designed to carry bulk materials such as coal, sand, gravel, oreminerals, etc. This belt can be troughed at 45° and is capable of transportingits load at a gradient of up to about 30° depending on the type of materialhandled.In addition to cover patterns, there are belts with high bonded sections.Section designs are varied and are vulcanized-on using the cold bondingprocess. These belts are named as follows:Partitioned BeltsFin-Type Belts ®CONTIWELL Box-Section Belts ®CONTIWELL Corrugated-Sidewall BeltsGradients of up to approx. 60° can be achieved using these belts,depending on the type of belt and the material being conveyed.Conveyor belts cannot be used for gradients exceeding 60° This is where .it becomes necessary to make use of vertical conveyors or elevator belts. ®CONTIWELL Box-Section Belts can also be used for vertical conveying(with a cover belt if required). Heavy-duty bucket elevators are fitted withElevator Belts with fabric or steel cable tension members.Steep-Angle Conveyor Belt with Partitioned Conveyor Beltchevron cleatsFin- Type Conveyor Belt, 2-section Fin- Type Conveyor Belt, 3-sectionCONTIWELL® Box-Section Belt 9
  17. 17. 10
  18. 18. ContiTech Specialist in Rubber Technology 2 2.1 How to order conveyor belts 2.2 Delivery and storageOrdering andstoringSite delivery
  19. 19. 2 Ordering and storage Ordering and storage 2.1 How to order conveyor belts Ordering is done on the basis of standards already named on the previous pages. In most cases reference can be made to specifications of systems already in operation when ordering replacement belts. Based on the DIN standard 22102, an enquiry or purchase order should include the following information: a) Extended or unwound length of the belt in m, specifying an "additional overlap length for splicing", or if the belt is to be delivered in one continuous length "endless...m". The client is responsible for specifying the correct length. b) Type of belt (e.g. steep-angle conveyor belt). c) Belt width in mm. Standard widths are 300, 400, 500, 650, 800, 1000, 1200 and so on at an increase of 200 mm. Non-standard widths may be supplied in agreement with the manufacturer. Continental manufactures belts up to a width of 3200 mm without a longitudinal joint. d) Type of reinforcement. e) Nominal strength of the belt in N/mm. f) Number of plies. g) Cover thicknesses (top and bottom) in mm. h) Cover material (rubber, PVC or the manufacturers designation). i) Cover grade, DIN 22102 code, basic properties, resistance requirements or the trade name if known. j) Additional information, e.g. type of splice. 2.1.1 Example of how to order Conveyor belt 40 m inner circumference, 500 mm width, 2 plies polyester/ polyamide, nominal strength 500 N/mm, rubber cover, cover thicknesses - top cover 3 mm, bottom cover 2 mm, belt to be supplied unspliced, additional overlap length for splicing required. This order is summarized as follows: ® 40 m CON-BITEX Conveyor Belt + overlap 500 mm wide EP 500/2 3+2 mm CONTINENTAL EXTRA (N) If you are ordering for the first time or planning to erect a new conveyor, you are strongly advised to complete the manufacturers data sheet giving full system specifications or ask for one of ContiTechs engineers to pay you a visit. This is the only way to ensure that you select the right type of belt with optimum conveying capacity and economy. 2.1.2 Delivery of endless belts Special-purpose belts and belts for short-distance conveyors can also be factory spliced to the clients specifications. Delivery of endless belts is however restricted by methods of transportation and production. Before ordering an endless conveyor belt, the question of installing it on the belt conveyor must always be examined. Installation of an endless belt requires at least prior dismantling of the drive and tail pulleys, as well as the sets of top run idlers. In addition, the feed and transfer points have to be thoroughly inspected.12
  20. 20. Ordering and storage 2The process of dismantling and refitting parts of the structure usuallyinvolves a great deal more work than on-site belt splicing and installation.ContiTechs specialist engineers can be of help when deciding whetherto select an endless belt or an unspliced one.A detailed summary of all ContiTech Conveyor Belt types, with descriptionsand information on available sizes can be taken from the CONTI ConveyorBelt Service Manual, Part C "Conveyor Belting, Product Range".2.2 Delivery and storageFor long-distance conveyors it is often necessary to divide the totalconveyor belt length into a certain number of part lengths agreed uponbetween the client and the manufacturer. The number of part lengths isalways kept as low as possible in order to keep the number of splices at theinstallation location to a minimum. Each splicing operation means a loss oftime and money.Part lengths are usually selected in accordance with the transportation andinstallation facilities at the site. Outer dimensions of the conveyor belt rolland its gross weight must be calculated beforehand when determining themode of shipment.2.2.1 PackagingConveyor belts are wound onto wooden cores for shipment. Light belts arewound onto wooden cores with 400 mm outside diameter and a squarecentre hole of 90x90 mm to hold the roll axle; long and heavy belts arewound on wooden cores with 600 mm outside diameter and a square centrehole measuring 200x200 mm to hold the axle.Extra large belt rolls can also be shipped on wooden or steel drums.When shipping endless belts the inner and outer loops are lined with rollersto prevent damage to the tension member through sharp kinking.The thickness of the conveyor belt can be determined by means of thetables on pages 4 and 5. Conveyor belt thickness = thickness of tension member + thicknesses of the two coversThe roll diameter can be taken from the graphs on pages 14 to 17 using thefactors belt thickness and belt length.The belt weight is determined with the aid of the following tables:- textile tension member (page 4)- steel cable belts (page 6)- cover materials (page 7). Net Belt weight [kg] = 2 2 . (cover weight [kg/m ] + tension member weight [kg/m ]) . belt width [m] belt length [m] 2 Cover weight [kg/m ] = 3 . density of cover material [kg/dm ] thicknesses of the two covers [mm]Formlua: 13
  21. 21. 2 Ordering and storageConveyor belt roll diameter with 400 mm core diameter 30 28 26 24 22 20 19 18 Roll diameter in mm 3000 2000 Belt thickness in mm 1000 100 200 300 400 500 Belt length in m14
  22. 22. Ordering and storage 2 Conveyor belt roll diameter with 400 mm core diameter 30 28 26 24 22 20 19 18 17 16 15 14 13Roll diameter in mm 1800 12 11 1700 10 1600 9 1500 8 1400 7 1300 6 1200 5 1100 1000 900 800 700 Belt thickness in mm 600 50 100 150 200 Belt length in m 15
  23. 23. 2 Ordering and storageConveyor belt roll diameter with 600 mm core diameter 30 28 26 24 22 Roll diameter in mm 3000 2000 Belt thickness in mm 1000 100 200 300 400 500 Belt length in mm16
  24. 24. Ordering and storage 2 Conveyor belt roll diameter with 600 mm core diameter 30 28 26 24 22 20 19 18 17 16 15 14 13Roll diameter in mm 12 1800 11 1700 10 9 1600 8 1500 7 1400 6 1300 5 1200 1100 1000 900 Belt thickness in mm 800 700 600 50 100 150 200 Belt length in m 17
  25. 25. 2 Ordering and storage Extra special care must be taken during loading and unloading. On no account should the belt be tipped from the truck or freight car as damage to the edges and covers would be inevitable. Lateral slipping of the roll (telescoping) too would complicate belt installation. If fork-lift trucks are used for unloading, the sharp-edged forks must be padded (corrugated cardboard, wood, conveyor belt waste, etc.). A suitable axle and a spreader must be used for loading and unloading by crane or hoist. If wire cables that touch the roll edges are being used, boards must be inserted, or better still, an additional strong wooden board of a length equalling the belt length can be wedged as a spacer bar between the two cable ends. If the belt roll has to be rolled, it is essential not to roll it counter to the winding direction. The roll is otherwise telescoped laterally into a funnel shape. Wooden boards should be placed underneath for rolling too, so that the belt is not damaged by stones or building materials. 2.2.2 Storage If prolonged intermediate storage is necessary, it is advisable to suspend the rolled belt with one axle in two mobile stands. If this is not feasible, the roll should be turned at intervals to change the contact surface. Storage location should be selected so as to avoid heat and direct sunlight. The belt should also be protected from contact with chemicals, grease or oil. Premature ageing, cracking, hardening or swelling would affect the service life of the conveyor belt (cf. DIN standard 7716, May 1982 - Rubber products: directions for storage, cleaning and maintenance). In the event of prolonged storage in the open air, the cut edges at the start and end of the belt have to be protected from moisture. It may be advisable ® to coat the edges with ContiTechs CONREMA Solution.18
  26. 26. ContiTech Specialist in Rubber Technology 3 3.1 Preparing the structure 3.2 Preparations for pullingPreparations for the belt onto the structureinstallationPulling in a STAHLCORD®Steel Cable Conveyor Belt
  27. 27. 3 Preparations for installation Preparations for installation Installing and splicing a conveyor belt is a job for experts. To give a proper description of these operations at this point would involve far too much detail (cf. Conveyor Belt Edition, "Installing and Splicing Conveyor Belts"). 3.1 Preparing the structure 11 10 1 13 8 6 12 2 17 5 15 7 9 16 4 3 14 1 Feed 9 Return run idlers 2 Discharge 10 Feed rollers 3 Head pulley (drive pulley) 11 Flat-to-trought transition 4 Snub or deflector pulley 12 Trough-to-flat transition 5 Tail or bend pulley 13 Feed chute (take-up pulley) 14 Belt cleaner (transverve scrapter) 6 Top run (tight side) 15 Belt cleaner (plough-type scraper) 7 Return run (slack side) 16 Drive unit 8 Top run idlers 17 Counterweight A thorough inspection of the entire structure for any defects or damage should be made before installing a new belt on an existing conveyor system. It is extremely difficult to check dimensions, take corrective action, replace damaged parts or do any welding jobs once the belt has been installed. The structure must be carefully cleaned and feed/discharge points cleared of any leftover materials. The whole length of the conveyor should be optimally aligned, i.e. straight-tracked without any twisting. The drive pulley, tail, snub and take-up pulleys should be set square to the centre line of the conveyor and be horizontal. If the pulleys are lagged, this is the best opportunity to inspect the lagging with optimum access to the pulleys. Various types of rubber lagging can be supplied for various applica- tions.The elasticity of rubber lagging and its grooves serve to effectively dissipate any moisture, prevent sticky materials from caking, as well as to cushion and accommodate stones depending on their size thereby keeping the belt in good working order. Friction grip of the rubber lagging is maintained. ContiTech supplies CORREX® Rubber Sheeting in different grades and surface patterns to cater for different needs. Lagging can also be applied to the pulleys after the system has been in operation.* * Further details of available types and instructions for lagging pulleys can be found in ContiTechs brochure, CORREX® Rubber Sheeting, Drum Lagging Materials and Abrasion Resistant Lining Materials.20
  28. 28. Preparations for installation 3The take-up station with the take-up pulley is positioned for textile fabricbelts at the point of the shortest belt length. After splicing of the belt,sufficient take-up must be available to offset the belt sag during installationand its elongation.Steel cable conveyor belts are low in elongation; the design engineer there-fore has to consider a shorter take-up than that for systems fitted withtextile fabric belts. Nevertheless, belt sag during installation must also betaken into account for steel cable belts.Once the belt has been adequately tensioned, it is recommended that thetake-up pulley or take-up carriage is adjusted so as to leave enoughbelt material for a join in the take-up length. The advantage of this is that itfacilitates dismantling of the pulleys during structure repairs, and in theevent of heavy damage to the belt, the belt can be tightened and a joinmade. Spindles, guides, rollers and hoists are to be cleaned and keptoperational.Idlers and idler sets in top and return runs are centered square to the beltline. Idlers have to be checked that they are rotating properly and that anymaterial build-up is removed. Idlers with dented or worn covering, as well asthose with bearing defects are to be replaced. Idlers have to be lubricatedfrom time to time depending on the type. Self-aligning idlers on the top andreturn runs must be cleaned, re-aligned and kept rotating freely. Returnidlers are exposed to heavy soiling and material build-up.ContiTech Support Rings protect the idlers from wear and materialaccumulation; they contribute to the true running of the belt and help tokeep the conveyor clean due to the low belt bearing area.Scrapers and chuting are always those elements which, together with theconveyed materials, contribute the greatest amount of wear to the conveyorbelt. Careful thought should be given during the initial phase of designing aconveyor system to ensure that the belt is subjected to the least amount ofpunishment. Deep troughing at the feeding point, restriction of the materialflow and suitable configuration of the belt charging point can nowadaysfrequently eliminate the need for chuting or at least enable its positioning sothat it has a protective instead of an abrasive effect on the belt.Scrapers are made from rubber or plastic according to their intendedapplication. The scraper material must be compatible with the materialsbeing conveyed in order to achieve optimum cleanliness and protectionagainst wear. Scrapers made from old conveyor belt waste, wood, steel orother materials lead to accelerated and premature wear of the belt.Weighted or even self-adjusting scrapers are to be checked that they canmove freely. Attachments are to be inspected for signs of damage, loosebolts or bent parts which could damage the belt.Rubber scrapers can only be set and adjusted once the belt has alreadybeen installed and tensioned because this is the only way to achieve thecorrect contact pressure on the belt cover.ContiTech supplies Scraper Blades made from different materials suited toindividual requirements of the material conveyed and the conveyor.** See details of ContiTechs product range. 21
  29. 29. 3 Preparations for installation Loading and transfer chutes, tip chutes as well as hoppers should be inspected and relined with abrasion resistant material if required. Metal wearing plates and braces should be firmly seated. Loose plates are frequently the cause of belt slitting. Excellent results are achieved with ® ContiTechs CORREX Rubber Abrasion Resistant Sheeting which can be subsequently applied using the cold bonding process.* ContiTech offers a versatile range of materials with different technical properties to suit various in-service requirements. ® CORREX Abrasion Resistant Material with adhesive layer (guide values) Type Thickness Specific Hardness Abrasion gravity (to DIN) in mm in kg/dm3 Shore A in mm3 6 8 10 15 ® CORREX L L 1.2 70 300 CYCLOP ® CORREX extra L L 1.1 60 110 ® CORREX super L L L L 1.1 55 55 ® CORREX red L L L L 1.1 45 200 ® 1) CORREX beige L L L L 1.0 40 90 ® CORREX red with L 1.1 45 200 herringbone pattern L=stock line rolls of 50m, approx. 1200 mm wide. Also spezial-purpose grades, e.g. „V“=self-extinguishing, „FW“=flame resistant, oil resistant within limits, etc., available on request. 1 ) Measured at half load. Standard sizes: Thickness Width Length 4-15 mm 1200 mm 50 m ≥ 16 mm 1400 mm 5m All safety devices must be carefully inspected! This not only includes guards around the belt motor drive and the erected awnings, but also all electrical monitoring systems, visual and acoustic warning signals, emergency switches, safety lines, belt mistracking and slip monitoring devices, incorrect loading/spillage control, slit detection systems, etc. This work should be carried out prior to actual belt installation. * See also ContiTechs brochure on CORREX® Rubber Sheeting, Drum Lagging Materials, Abrasion Resistant Lining Materials.22
  30. 30. Preparations for installation 33.2 Preparations for pulling the belt onto the structureIt is particularly important when setting up a new conveyor system that, priorto installation, a site inspection plus preliminary discussions on theprocedure take place between engineers in charge from both the conveyorconstruction company and the belt manufacturers, as well as competentmaintenance and electrical engineers from the client. During these discus-sions an installation programme should be established, the provision ofauxiliary equipment and assisting engineers/staff planned, and the differentareas of responsibility determined.The site for hanging the new belt in let-off stands, the optimum method ofpulling the belt onto the structure and the site for intermediate and finalsplicing should also be jointly agreed upon.3.2.1 Hanging the belt roll in let-off standsThe winding method is governed by local conditions. The belt roll issuspended in mobile let-off stands, the simplest type of which is fitted withopen U-shaped bearings to support the axle ends. Bearings should besecured by bolts or stirrups. For small conveying systems, mobile cable reeljacks are also adequate for hanging in the roll.For conveying systems over substantially different levels of ground, the beltmust be pulled in upwards using an appropriate hoist or downwards ontothe system by means of suitable braking and intercepting devices capableof effectively moderating the maximum slope fall.To ensure the belt is pulled straight onto the system, the roll should as far aspossible be positioned at right angles to the centre line of the system andcentered in front of, behind, below or above the structure. If it is onlypossible to pull the belt in from the side, it should be done at an acute angleto the system. This requires a number of deflection idlers and fender rollersbetween the unwinding point and entry onto the structure or groups oflaterally extended troughing idlers to form a lead-in guide onto the centre ofthe system. All short twists and bends must be avoided when pulling thebelt onto the structure and particular care should be taken to avoid anytendency to tear the belt edges.3.2.2 Pulling in the beltBefore belt installation, all parts of the structure that come into direct con-tact with it must be cleaned of oils and lubricants. The belt may not bedragged across sharp-edged steel sections or wall edges. Fender rollersmust be fitted at such points. The process itself of pulling in the belt is alsodetermined by local conditions. Although small belts can be lifted manuallyor with pulling cables or a hoist, long belts require motor-driven cablewinches or cables with corresponding traction vehicles such as trucks,Unimogs, bulldozers, etc.Prior to lifting the belt onto the system, a control must be made to ensurethat the top cover of the belt will come to rest upwards in the top run anddownwards in the return run. If the top cover of the belt is not marked with astamp, it can be recognized by the cut edge at the beginning of the belt asthe thicker of the two covers. 23
  31. 31. 3 Preparations for installation The top cover of a rolled belt usually faces outwards. If the suspended roll is unwound from above, the outer cover is also on top when the belt enters the conveyor system. If the roll is turned so that unwinding is done from below, the outer cover faces downwards. If the worn belt of a conveyor system is to be replaced by a new one, the easiest method is often to attach the new belt to the old cut belt so that when winding up the old belt the new one is automatically drawn onto the system. The method chosen is best left to the discretion of the supervising engineer. There are a number of different possibilities depending on site conditions, but it would involve too much detail to explain them all in this brochure.24
  32. 32. ContiTech Specialist in Rubber Technology 4 4.1Splicing fabric-ply conveyor belts 4.2 Splicing steel cable conveyor beltsSplicing conveyor beltsHot vulcanizing press
  33. 33. 4 Splicing conveyor belts Splicing conveyor belts Depending on the length of a conveyor system, the belt is made endless either by splicing its two ends after it has been drawn onto the structure, or by suitably splicing the individual part-lengths to form one continuous length. 4.1 Splicing fabric-ply conveyor belts There are two methods of splicing fabric-ply belts. 4.1.1 Mechanical splices (detachable) Detachable splices using mechanical fasteners are recommended for conveyor belts which have to be frequently replaced, shortened or lengthened, as in underground mining service. The mechanical splice is quick to carry out and allows the conveyor to resume operation after just a short time. Another advantage is the low loss of belt material - splicing is done with straight, rectangular belt ends and the fasteners do not extend far into the belt, which means little waste when making a new splice or replacing a defective one. Utilization of the belt strength varies to a great degree when using mechanical fasteners. It depends largely on the type of belt, the type of fabric in particular as well as on the type of fastener, and ranges between 50% and 90%. If a thin, flexible belt is to be joined with mechanical fasteners, care should be taken that the pulley diameters are suited to theHook fasteners fastener holding ability. 4.1.2 Vulcanized splices (non-detachable) The commonest and most successful type of splice for fixed conveyors and heavy-duty belts is still the hot vulcanized or cold vulcanized splice. If made properly by an expert, this splicing technique guarantees maximum utiliza- tion of the belt strength, longest service life and the best tracking properties of the belt. These splices also display optimum properties when chuting is used at loading points or when scrapers are fitted to eliminate material build-up or clean the belt. Fabric-ply conveyor belts are normally spliced with staggered steps and butting of the corresponding fabric plies of the two belt ends.26
  34. 34. Splicing conveyor belts 4 The splice is the weakest point in the entire belt. Due to this method of stepping the plies, one fabric ply has to be omitted reducing the tensile strength of the joint by a percentage which is related to the overall number of plies in the belt. The lower the number of plies, the greater the loss of strength as a percentage of the overall belt strength. The high tensile strength of todays fully synthetic fabrics enables conveyor belts to be manufactured in all strengths up to 1250 N/mm belt width with ® just two fabric plies. The special feature of the CON-BITEX Belt is its thicker rubber interlayer which permits various types of splices to be made.Two-step splice Whereas the one-step splice only transmits approx. 50% of the belt strength, up to 100% of the belt strength can be attained using additional fabric or the interlaced splice. The strain on the splice when bending over idlers and pulleys is reduced by taking a bias length of . LA = 0.3 B The additional belt length for the splice overlap is therefore .One-step splice LVZ = z LS + LA for fabric-ply belts with z number of steps. Step length LS is determined by the strength of the individual fabric plies.Splice with additional fabric ®(CON-BITEX )Interlaced splice ®(CON-BITEX ) 27
  35. 35. 4 Splicing conveyor beltsSplice dimensions for fabric-ply belts Belt type Step length Number of steps Additional belt length for overlap LS in mm z LVZ in mm ® . CON-MONTEX 160/1 200 1 200 + 0.3 B 200/1 250 250 250/1 250 250 315/1 300 300 400/1 300 300 500/1 350 350 ® CON-BITEX one-step or with two-step or additional fabric interlaced . 200/2 180 180 + 0.3 B 360 + 0.3 250/2 180 180 360 315/2 180 280 360 400/2 200 200 400 500/2 200 200 400 630/2 250 250 500 800/2 250 250 500 . B 200/3 100 2 200 + 0.3 B EP 200/3 100 200 250/3 150 300 315/3 150 300 400/3 200 400 500/3 200 400 630/3 250 500 800/3 250 500 1000/3 300 600 1250/3 300 600 . B 250/4 100 3 300 + 0.3 B EP 400/4 150 450 500/4 200 600 630/4 200 600 800/4 250 750 1000/4 250 750 1250/4 300 900 1600/4 300 900 . B 315/5 100 4 400 + 0.3 B EP 500/5 150 600 630/5 200 800 800/5 200 800 1000/5 250 800 1250/5 250 1000 1660/5 300 100028
  36. 36. Splicing conveyor belts 44.2 Splicing steel cable conveyor beltsIn a steel cable conveyor belt splice the individual corresponding cables ofthe two belt ends are placed side by side alternately and embedded in aspecial rubber compound. The type of splice used is predetermined foreach belt strength rating by the diameter and spacing of the cables.Splicing configurations to DIN 22131 (provisional standard)one-step splicetwo-step splicethree-step spliceSteel cable belts too are normally spliced at a bias of . LA = 0.3 belt width BRight-angle joints are possible if suitable equipment is available. 29
  37. 37. 4 Splicing conveyor beltsRecommended splice dimensions for steel cable belts to DIN 22131and special types (guide values) Belt type Step length Number of steps Additional belt length for overlap LS in mm z LVZ in mm + LA St 500 250 1 550 St 630 250 1 550 St 800 300 1 600 St 1000 300 1 600 St 1250 350 1 650 St 1400 350 2 1000 St 1600 450 1 750 St 1800 400 2 1150 St 2000 400 2 1150 St 2250 400 2 1150 S1 2500 500 2 1350 St 2800 600 2 1550 St 3150 650 2 1650 St 3500 650 3 2350 St 4000 750 3 2650 St 4500 800 3 2800 St 5000 Splicing system is chosen in accordance with design conditions St 5400 St 6300 St 7300Other splicing systems are possible A great amount of research and testing is invested by ContiTech in the improvement of splicing methods to achieve optimum splice life and yet keeping the cost of labour and equipment to a minimum. The importance of precision and skill during splicing cannot be overemphasized. Further details are given in the edition "Installing and Splicing Steel Cable Conveyor Belts".30
  38. 38. ContiTech Specialist in Rubber Technology 5 5.1 Tensioning the belt 5.2 Starting the belt 5.3 Training the beltCommissioningLong-distance conveyorin operation
  39. 39. 5 Commissioning Commissioning After splicing the conveyor belt, the press, worktop and all auxiliary splicinig facilities are dismantled and removed. Idler sets are returned to their positions in the top and return runs, properly aligned and secured. 5.1 Tensioning the belt It is assumed that the structure will have been erected correctly before belt tensioning takes place. If using the screw take-up method, the take-up gear on either side of the take-up pulley is to be adjusted so that the pulley with- draws square to the centre line of the system, thus tensioning the belt. With a gravity take-up, the supported counterweight is returned to its hanging position, or alternatively the winch tightened accordingly in the case of winch tensioning. The belt must be tensioned so as to ensure that a) the required tension is available at the drive to effectively transmit the peripheral force of the drive to the belt. Insufficient tension leads to belt slip on the pulley, premature wear of both belt and lagging, causing interference during operation. b) there is no belt sag between the individual idler sets and that troughing does not flatten to allow material spillage. c) the belt shows a good flat-to-trough transition even when running with no load, thereby gaining enough friction contact with the lateral idlers to keep it running true. For small conveyor systems, the expert installation engineer will be able to adjust the correct tension on the basis of experience. For large conveyor systems, the required tension is pre- determined during the design phase, or calculated from the required tension of the pulley and permissible sag of the belt between idlers. 5.2 Starting the belt All is now prepared for the initial run, however it is recommended that the entire system is inspected again before starting the commissioning operation. Any tools left lying around or parts of the structure, screws, etc. placed on the return run are to be removed. If necessary, the return run should be swept clean again. Check that work has been satisfactorily completed on all parts of the system. A locking device over the electric switch has proved to be an effective precautionary measure in this connection. It is secured by each group of workers with a marked padlock and the conveyor is not released for commissioning until all padlocks have been removed.32
  40. 40. Commissioning 5If the system has a large centre distance, it is advised that a team of capableobservers be posted at intervals along the conveyor in such a manner as toenable visual and audible signalling. First of all the belt is switched onbriefly to move it forward about 10 to 15 m depending on the system length.This makes sure that the belt initially rests properly on the idlers. Then asecond short burst of power is given, after which the supervising engineerawaits the reaction of his observers. If no problems are reported, the beltcan be run under steady power. Constant monitoring is important to see ifthere is a tendency to run out of line, so that corrective action can be taken.Fabric-ply belts in particular require a certain amount of time beforerunning with load to allow them to adapt to the system configuration andtroughing. If a belt shows a tendency to run off-centre at the beginning,there is no reason to interrupt the trial run and expect to find the cause inthe work of the vulcanizers or even a faulty belt. Every start-up operationneeds corrective action. Belt and system must adapt to one other. This isbest done with the belt running, if possible under full load conditions.5.3 Training the beltTraining a belt, especially on a long conveyor system, requires a great dealof patience, clear logical thinking and action. If at the beginning the beltcomes into contact with some points of the fixed structure, the conveyordoes not have to be stopped immediately - belt edges do not suffer thedamage that easily. Alignment is only possible when the belt is running,because it is only during operation that the effect of any adjustment can beobserved. If the belt runs off-centre, correction begins before the point ofmisalignment seen in the direction of belt travel.How can misalignment be corrected?The drive pulley has been thoroughly checked during preparations forcommissioning: it is horizontal and set square to the belt axle. It has beencleaned of all caked material. Therefore, this pulley should as far aspossible be left untouched. If the belt does not centralize, the final troughingidlers before the drive pulley are to be adjusted.The tail pulley, often designed as a take-up pulley on small conveyors isusually screw-adjusted. Though it would be preferable to leave the pulley inthe position it was during control of the belt tension, belt tracking can becorrected at this point if absolutely necessary.The general rule is: Conveyor belts enter downwards 33