Step 1 Determine Conveyor Capacity Conveyor capacity in tons per hour (TPH) should be peak or surge volume rather than average volume.

Transcription

1 Goodman Conveyor Idler Selection Procedure Step 1 Step 2 Step 3 Step 4 Step 5 Step 6 Step 7 Step 8 Step 9 Determine conveyor capacity of material to be handled in tons per hour (TPH). Determine material and its characteristics. Choose troughing angle. Determine minimum belt width based on lump size. Select a suitable belt speed. Select required belt width. Determine actual troughing (carrying) idler load and idler spacing. Select troughing (carrying) idler series. Determine return idler load and idler spacing. Step 10 Select return idler series. Step 11 Determine idler bearing L10 life correction. Step 12 Determine potential idler life. Step 13 Determine Goodman Conveyor idler specification and model numbers. Step 14 See Pages 28 and 29 for regreaseable and sealed for life option for series C, D, and E idlers. Step 1 Determine Conveyor Capacity Conveyor capacity in tons per hour (TPH) should be peak or surge volume rather than average volume. Step 2 Determine Material Characteristics Table 1 lists major characteristics for most common materials capable of being handled by belt conveyor. Table 2 lists material class description. Table 3 lists flowability, angle of surcharge, and angle of repose. These important characteristics require definition: The angle of repose of a material is the angle which the surface of a normal, freely formed pile makes to the horizontal. The angle of surcharge of a material is the angle to the horizontal which the surface of the material assumes while the material is at rest on a moving conveyor belt. This angle usually is 5' to 15" less than the angle of repose. The flowability of a material, as measured by angle of repose and angle of surcharge, determines the cross section of the material load which can be carried safely on a belt. It is also an index of the safe angle of incline of the belt conveyor. 4-BELT CONVEYOR IDLERS

2 Table 1-Material Characteristics and Weight per Cubic Foot Material Average Weight Lbe. Per Cu. Ft. Material Class Maximum Surcharge Angle Degrees f Acid Phosphate, Pulverized Alum, Lumpy Alum, Pulverized Alumina Aluminum Hydrate Aluminum Oxide Aluminum Sulphate Asbestos, Ground Asbestos, Shredded Asbestos, Solid Ashes, Dry, Loose (Coal) Ashes, Wet, Loose (Coal) Asphalt, Crushed, % lnch & Under Attapulgite Clay Bagasse Bakelite, Powdered Baking Powder Barite Bauxite, Crushed, 3 lnch & Under Beans, Castor, Whole Bones, Crushed Bones, Ground, Dry Borax, Fine, Y2 lnch Screenings Borax, 3 lnch & Under Bran Brewers Grain, Spent, Dry Brewers Grain, Spent, Wet Calcium Carbide, Crushed Carbon, Activate, Dry, Fine Carbon Black, Pelletized Cement Clinker Cement, Portland, Aerated Cement, Portland, Packed Chalk, Crushed Charcoal, Ground Charcoal, Lumps Cinders, Blast Furnace Cinders, Coal, Ashes & Clinker Clay, Dry Lump Clover Seed Coal, Anthracite, R.O.M. Coal, Anthracite, Solid Coal, Bituminous, R.O.M. Coal, Bituminous, Solid Coal, Lignite Coffee, Roasted Beans * May vary considerably A When handling large lumps at speeds over 400 FPM, do not use a slope greater than 15' BELT CONVEYOR IDLERS-5

3 Table 1 (continued) Concrete, Cinder Concrete, Mix D26 15 Copper Ore *D Copper Sulphate Cork, Ground Cork, Granulated Cottonseed, Dry, Delinted Cottonseed, Meal Cullet, Glass, Average Dolomite, Pulverized Dolomite, Lumpy Earth, Common Loam, Dry Earth, Common Loam, Moist Earth, Mud, Wet, Containing Clay Earth, Diatomaceous Feldspar, % Inch Screenings Feldspar, 1 Y2 to 3 Inch Lumps Feldspar, Powdered, 0 Mesh Firebrick (%" x 0") Flaxseed Flint, Pebbles Flour, Wheat Flourspar, '/2 Inch Screenings Flourspar, Lumps, 1% to 3 Inch Fullers Earth, Dry Fullers Earth, Oily Garbage, Average Glass Batch (Wool & Container) Gneiss, Lumps Grain Barley (48 # Bu.) Corn, Shelled (56# Bu.) Flour, Wheat (196 # Bu.) Oats (32# Bu.) Rye (56# Bu.) Wheat: (60 # Bu.) Granite, 1 '/2 to 3 Inch Lumps Granite, Broken Gravel, Mixed Sizes Greenstone, Lumps Gypsum, '/2 Inch Screenings Gypsum, 1 Yi to 3 Inch Lumps * May vary considerably D36 BMY C C35 W B35W D37Z 836 D36 B A36MY B36 D36 A37 B25NW APN C46 D 'EVW D38Z B25N C25NW APN C25M B25N C25N D27 D37 C36 D BELT CONVEYOR IDLERS

4 Kaolin Clay, 3 Inch & Under 63 D Lead Ores "B36RT Lignite, Air-Dried -55 "D Lime, Hydrated, Pulverized A35MXY Lime, Ground,?4 Inch & Under B35X Lime, Lumps Limestone, Crushed C36X Limestone, Agricultural,?4 lnch & Under 68 B Malt, Dry, Whole C25N -29 Malt, Wet or Green C Manganese Ore *D37 39 Marble, Crushed, 1/2 Inch & Under D Mica, Ground " Milk, Dry, Powder 36 BP Molybdenite, Powdered 107 " Molybdenum Ore 107 B36 40 Oyster Shells, Ground, Under % Inch D36T Paper Pulp Stock *El 5MV 19 Peanuts, Shelled 35- C35Q Phosphate Rock, Broken, Dry D Phosphate Rock, Pulverized 60 B Phosphate Triple Super, Ground Fertilizer BT Potash (Muriate), Mine Run 75 D Quartz, 1 '/z to 3 Inch Lumps D27Z -29 Resin, Vinyl Rice, Hulled or Polished -48 B Rice, Rough 36 B35M Rock, Crushed D26-29 Rock, Soft, Excavated With Shovel D Rubber, Ground 24,Rubber, Pelletized D Salt, Common Dry, Coarse C36TU 22 Salt, Common Dry, Fine D26TUW Salt Cake, Dry, Coarse 85 B36TW Salt Cake, Dry, Pulverized B26NT -29 Sand, Bank, Dry B * May vary considerably BELT CONVEYOR IDLERS-7

5 Table 1 (continued) B27 Sand and Gravel, Wet Sandstone, Broken "B35 Sewage, Screenings, Drained Sewage, Sludge, Raw Shale, Crushed Shot, Steel Silica, Flour Slag, Blast Furnace, Crushed Slag, Furnace, Granular, Dry Slag, Furnace, Granular, Wet Soap Chips Soap Powder Soda Ash, Heavy Soda Ash, Light Soda, Bicarbonate Soy Beans, Cracked Soy Beans, Whole Soy Bean Cake, Over '/2 Inch Soy Bean Flour Soy Bean Meal Steel Turnings Stone, Crushed Sugar Cane, Knifed Sugar, Raw, Cane Sulphur, Lumps, 3 Inches & Under Sulphur, Powdered E25TW C36 A27 C27 B47 C35Q B25X B36 A36Y AY C36NW C27NW D35W C25Y 835 EV B46TX Taconite Pellets Tanbark, Ground Tobacco Traprock, 1/2 Inch Screenings Tungsten Carbide, Powder D37Q DY C White Lead Wood Chips Wood Flour Zinc Ore, Crushed Zinc Oxide, Heavy A36MR EWY * AX * May vary considerably 8-BELT CONVEYOR IDLERS

6 Using Tables 2 and 3, select and record: A) Weight of material in pounds per cubic foot C) Abrasiveness of the material B) Surcharge angle and flowability D) Corrosiveness of the material Table 2-Materi I Flowability and Angle of Repose I Abrasiveness Misceilaneous Characteristics (Sometimes more than one of these characteristics 11 Class Description Material Characteristics Very fine-100 mesh and under Fine-% inch and under Granular-under 1/2 inch Lumpy-containing lumps over 1/2 inch Irregular-stringy, interlocking, mats together Very free-flowing-angle of repose less than 19" Free-flowing-angle of repose " to 29" Average flowing-angle of repose 30" to 39' Sluggish-angle of repose 40" and over Nonabrasive Abrasive Very abrasive Very sharp-cuts or gouges belt covers Very dusty Aerates and develops fluid characteristics Contains explosive dust Contaminable, affecting use or saleability Degradable, affecting use or saleability Gives off harmful fumes or dust Highly corrosive Mildly corrosive Hygroscopic Interlocks or mats Oils or chemical present-may affect rubber products Packs under pressure Very light and fluffy-may be wind-swept Elevated temperature Code Example: A very fine material that is free-flowing, abrasive, and contains explosive dust would be designated: Class A26N. Table 3-Flowability, Angle of Surcharge, Angle of Repose coal, cottonseed * Code designations conform to bulk material characteristics chart, Table 2. Note: Use this table to obtain surcharge angle, if not listed in Table 1. BELT CONVEYOR IDLERS-9

7 k.. Step 3 Select Troughing Angle of Carrying Idlers As the capacities in Table 7 indicate, idlers with end rolls set at 35' and " angles give greater carrying capacity for a given width. These steeper troughing angles necessitate a greater transverse flexibility in the conveyor belt. However, improvements in belt carcass design and materials have contributed to wider acceptance and greater use of 35" and O troughing idlers. Final selection will be dependent upon material characteristics and conveyor belting. How- ever, for most materials we recommend 35' be selected based on economy. " troughing - idlers are widely used when conveying grain or other free-flowing, nonabrasive materials. When using steeper troughing angles, follow recommendations for minimum transition distances for idler adjacent to terminal pulleys. See Table , -, p pi^ ltm.nsit34n distq Terminal Pulley '., Terminal pulley. 61,or ne 112 trough depth. \.. 4. \. - _. - ~ ,, ",-., - Minimum transition distance Table $-Recommended Minimum Transition Distances Idler Angle., Fabric Belts w - -.z. -..., --. y4@&fgh~~@tb -.. ~ig!:~~b.~~hpe~tk ' % T~<cI~~I&$I ',., '*,,.- - ' T%&, ',.,. 2Rb. t.- i.k!b,,,. - I.&.' b,.. - 3&6-. 1,, -,?.a-.: i,,.-. -, 1#0b,, - 'i'., "<f<,., 1-3.2b : *. 3;ab. 1 "a@:- j-:.. :f < ":-{~l;%.y,qj....i.6b, ' - -1 l,.b&-c- &: ;- "$.. :-=> I " 2:&izg3&;+,ai2r--L. P,--;, -;JI;K~~J, r'y 7.,.z,>,=. ' e:dd,. -., F :.'. ' ',.. 1,gh ' b, 2.4b. 2:3b. ' % Rated Tension Over 90 " 60 to 90 Less than 60 Over 90 35" 60 to 90 Less than 60 Over 90 O 60 to 90 Lessthan60 b = Belt width (transition distance will be in the same units as those used for b). Steel Cable Belts,, &Ski. A?.. ' $%$fc@&h7@&h. ai@b,*% c -- e,?, m 6.Bp -, :..32&br7tr ' I -..- I--- -.,8,06f:,~. 5 - b;4@ 1.,%. :. 4.4b 10-BELT CONVEYOR IDLERS

8 I step 4. I Determine Minimum Belt Width Based On Lump Size Use Table 5, which is based on a ' angle of surcharge. For a 30" angle of surcharge, limit lump size to 50% of those listed in table. Lump size will influence the belt specifications and choice of carrying idlers. Select a Suitable Belt Speed For Required Capacity I Use Table 6 as a guide. Under favorable loading and transfer conditions for troughed belts wider than 30 inches, speeds in excess of those specified in Table 6 are occasionally used for fine materials, damp sand, coal, earth with no large lumps, and crushed stone. An increase in belt speed permits decreases in belt width and tension. However, these benefits must be weighed against the disadvantages of increased belt wear, material degradation, lump impact on carrying idlers, and generally reduced life of all conveyor components. Design of the loading area and the discharge of the material over the head pulley must be considered.when selecting the belt speed. The belt speed also has a significant affect on idler life. This is discussed in step 11. NOTE: Select maximum belt speed for use in completing Step 6. Belt speed can be finalized after completing Step 6. Grain or other free-flowing, nonabrasive material Table 5-Maximum Lump Sizes Coal, damp clay, soft ores, overburden and earth, finecrushed stone Feeder belts, flat or troughed, for feeding fine, nonabrasive, or mildly abrasive materials from ~ O D D and ~ ~ bins S Sized In Inches Unsized Material (Mixed With Not Over 10% Of Whole Of Whole " Surcharge " Surcharge ; ; j 1 in Table 6-Recommended Maximum Belt S~eeds Heavy, hard, sharp-edged ore, coarse-crushed stone Foundry sand, prepared or damp; shakeout sand with small cores, with or without small castings (not hot enough to harm belting) Prepared foundry sand and similar damp (or dry abrasive) materials discharged from belt by rubberedged plows Nonabrasive materials discharged from belt by means of plows , except for wood pulp, where 300 to 400 is oreferable Over 36 Any width Any width Any width Any width I Belts with trippers I 400' 1 Any width I *For speeds over 400 FPM, special design consideration must be given to tripper chute design and tripper drive, Tripper propelled (driven) by belt alone is not recommended. BELT CONVEYOR IDLERS-1 1

9 Step 6 Select Required Belt Width A) Make selection based on peak or surge load (TPH) being 80% of the full cross-sectional load area of the belt. Note: This 80% factor may vary depending on design practice, conditions, preference, etc. B) Either of two methods can be used to select belt width (BW). Method 1 a) Convert the desired TPH to be conveyed to the equivalent in cubic feet per hour (FT3/HR).,...f-7dy r 2-,-,,. y$gj ' ' -- ' ma=.-- '*-?c&y4fs9.wa2 7 TPH x 80 LES/TON 7% 2 FT3/HR = Material Density (LBS/FT3) x 80%,in.. 2 b) Convert the desired capacity in cubic feet per hour to the equivalent capacity at a belt speed of 100 FPM. c) Using Table 7, find correct surcharge angle and troughing angle, then select a belt width. Check this selection against minimum belt width selected in Step 4. d) Determine final or design belt speed (FPM). Method 2 a) Determine cross section of load (sq. ft.) required, using the following formula: I b) Using Table 7, find correct surcharge angle and troughing angle, then select a belt width. Check this selection against minimum belt width selected in Step 4. c) Determine final or design belt speed (FPM). TPH x TOO0 LBS/TOR sr* ''' SeIecIed BY Crnss Setti. 11 M [So x Murial Density [LEm3] x 60 MN/HR x I 80%@ C 12-BELT CONVEYOR IDLERS

10 - Table 7-Capacities and Areas of Troughed Belt Idlers-Equal Length Rolls Trough Angle m Belt Widtt.7!9!,%1 L? Cross Section of Load Surcha 22BEii.081.I I Sq. Ft. Note: The data shown in Table 4 is based on standard edge distance = 0.055b inch. b = Belt Width in Inches For good conveyor design, size belt to handle 80% of peak tonnage. Refer to Tables 1 and 3 for surcharge angles.! - Capacity in Cu. Ft. >er Hour at 100 FP Surchal je Angle "$.gr?'; BELT CONVEYOR IDLERS-13

11 Step 7 Determine Troughing (Carrying) ldler Load and Spacing Calculated ldler Load (Ibs.) =ICIL = ((WB + (WM x KI)) x SI) + IML~....., I Where: WB = Belt weight (Ibs./ft.) use actual or estimate from Table 8 WM = Material weight (Ibs./ft.) =I(TPH x 00) l(60 x FPM)~ TPH = Quantity of material conveyed (Tons per hour) FPM = Design belt speed (Feet per minute) SI = Spacing of idlers (ft.) see below and Table 9 K1 = Lump adjustment factor (see Table 11) Note: Actual weight of lump should be compared with WM value. In situations, it may be necessary to use actual lump weight as WM. IML = ldler misalignment load (Ibs.) due to idler height deviation and belt tension = [(D x T) / (6 x SI) ~here:l D = Misalignment (inches) T = Belt tension (Ibs.) SI = ldler spacing (feet) When an idler is higher than adjacent idler, a component of belt tension will add load to that idler. The amount of height deviation can vary with the installation and type of idler, especially when training idlers are used. CEMA publication on conveyor installation standarts (Appendix D, Belt Convevors for Bulk Material, fifth edition or later) list recommendations on structure misalignment). Spacing of Idlers: Factors to be considered when selecting idler spacing are belt weight, material weight, idler rating, belt sag, idler life, belt rating and belt tension. Table 9 lists suggested normal troughing idler spacing for use in general engineering practice. Conveyor systems can be designed utilizing extended idler spacing andlor graduated idler spacing. Extended idler spacing is simply greater than normal spacing. Graduated idler spacing is greater than normal spacing at higher tension portions of the belt. Advantages may be lower idler cost (fewer used) and better belt training. For general conveyor design and selection, limit belt sag to 2% of idler spacing (Table 10). If other than normal idler spacing is used, care should be taken not to exceed idler rating and sag limits during starting and stopping. For a detailed engineering analysis on belt tensions, sag and extended idler spacing, use CEMA handbook "Belt Conveyors For Bulk Materials." 14-BELT CONVEYOR IDLERS

12 'able 8-Estimated Average lelt Weight, Multiple-and {educed-ply Belts, Lbs. / Ft. lnches (b) rial Carried, Table 10-Spacing for 2% Belt Sag IN FEET = SI Steel cable belts-increase above value by 50%. Actual belt weights vary with different constructions, manufacturers, cover gauges, etc. Use the above values for estimating. Obtain actual values from the belt manufacturer whenever possible. Example: Wm = 85 LB/FT Wb = 15 LB/FT Si =4FT To = 2500 LBS 'able 9-Suggested Normal Spacing in :eet of Belt Idlers (SI), ". ', -, /&2L-,.. =-:. <. -. 2:%&&&afiffi-di%&&&<ff:,,:~.&k..:&~*$<~~?q Belt Width Weight of Material Handled, Lbs. Per Cu. Ft. ~etur* Inches , Idlersf O Spacing may be limited by load rating of idler. See idler load ratings in tables. These spacings do not restrict the amount of belt sag to any specific percentage. See Table 4 for spacing of idlers adjacent to terminal pulleys. Recommended spacing at loading points is half normal spacing listed unless impact forces indicate a smaller spacing. Belt tension for 2% sag To = 6.25 x SI x (Wm + Wb) BELT CONVEYOR IDLERS-1 5

13 Table 11-K, Lump Adjustment Factor Step 8 Select Troughing (Carrying) ldler Series A) Use CIL, belt width and troughing angle determined from previous steps and select the required idler series from Tables 12 thru 15. B) CIL should be equal to or less than idler load rating selected. C) See table 16 for idler roll recommendations. D) The troughing idler selection procedure for calculated idler load (CIL) does not include the following: 1. Impact force on idler at conveyor loading points. 2. Effect of belt transitions (head and tail pulley) on idler load. 3. Loads imposed on idlers located within vertical curve areas. Contact Goodman Conveyor Co. for any required assistance for these load conditions. Step 9 Determine Return ldler Load and Spacing. Calculated ldler Load (Ibs.) =ICIL, = (WB x SI) + IML ( Refer to Step 7 for nomenclature. Belt sag between idlers should be limited to approximalely 2% of return idler spacing. If extended return idler spacing is used, belt sag should be investigated thoroughly. Step 10 Select Return ldler Series. A) Use CIL, and belt width determined from previous steps and select the required idler series from tables 12 thru 15. B) CIL, should be equal to or less than idler load rating selected. C) For long-center belt conveyors the use of Vee return idlers should be considered. D) Roll diameter and roll type for return idlers may be different from troughing side if desired. The return belt contacts the dirty side of the belt, resulting in abrasive wear of the idler roll surface. Materials build up on the roll and increase its effective diameter. Because the buildup is never uniform, and usually is less at the belt edges, the clean sections of the roll travel at a slower surface speed than that of the belt. This results in a relative slippage, there by accelerating wear of both the belt cover and the surface of the roll. Thus the life of the roll shell is usually shorter on return belt idlers than on carrying idlers. E) See Table 16 for idler roll recommendations. 16-BELT CONVEYOR IDLERS

14 Table 12-Load Ratings for Series B Idlers, LBS (Riaid Frame) Single h I F ; ; 1 Trough Angle I Roll I (Inches) Return Table 1 %Load Ratings for Series C Idlers. LBS (Riaid Frame) Belt I Trough Angle Width (Inches) Return Return RATINGS BASED ON MIN. L OF HOURS AT 500 RPM RATINGS BASED ON MIN. L* OF 60,000 HOURS AT 500 RPM FOR C AND CSL SERIES WlTH TAPERED ROLLER BEARING. BC SERIES WlTH BALL BEARING HAS L,, OF 30,000 HOURS. 'USE CEMA D RETURN IDLER. Table 14-Load Ratings for Series D Idlers, LBS (Rigid Frame) Table 15-Load Ratings for Series E Idlers, LBS (Rigid Frame and Catenary Where Applicable) I (Inches) 1 " ( Return I Return I NOTES: RATINGS BASED ON MIN. L, OF 60,WO HOURS AT 500 RPM RATINGS BASED ON MIN. L OF HOURSAT 500 RPM 1. TROUGHING IDLER LOAD RATINGS (TABLES 12 THRU 15) ARE FOR THREE EQUAL LENGTH ROLLS. 2. LOAD RATINGS ALSO APPLY FOR IMPACT ROLLS. 3. TROUGHING IDLER LOAD RATINGS ARE BASED ON A LOAD DISTRIBUTION OF 70% ON CENTER ROLL AND 15% ON EACH END ROLL FOR ALL TROUGH ANGLES. 4. UNEQUAL LENGTH ROLLS OR PICKING IDLERS ARE NOT COVERED BY THESE TABLES. IDLER LIFE Idler life is determined by a combination of many factors, such as seals, bearings, shell thickness, belt speed, lump sizelmaterial density, maintenance, environment, temperature and the proper series of idler to handle the maximum calculated idler load. While bearing life is often used as an indicator of idler life it must be recognized that the effect of other variables (e.g., seal effectiveness) may be more important in determining idler life than the bearings. Nevertheless, since bearing rating is the only variable for which laboratory tests have provided standard values, bearing L, life is used as a guide for establishing idler ratings. See page 28 for details on Goodman's exclusive PERMASEAL IImnon-purgeable sealing system. This time tested and field proven design is the best seal on the market. BELT CONVEYOR IDLERS-1 7

15 The definition of L, for belt conveyor idlers: The basic rated life (number of operating hours at 500 RPM) based on a 90 percent statistical model which is expressed as the total number of - revolutions 90 percent of the bearings in an apparently identical group of bearings subjected to identical operating conditions will attain or exceed before a defined area of material fatigue (flaking, spalling) occurs on one of its rings or rolling elements. The L,, life is also associated with 90 percent reliability for a single bearing under a certain load. Tables 12 thru 15 show load ratings for series B, C, D, and E idlers. These load ratings are based on the following: Series B load rating based on minimum L, of 30,000 hours at 500 RPM. Series BC (Ball Bearing) load rating based on minimum L, of 30,000 hours at 500 RPM. Series C (Tapered Roller Bearing) load rating based on minimum L, of 60,000 hours at 500 RPM. Series D load rating based on minimum L, of 60,000 hours at 500 RPM. Series E load rating based on minimum L, of 60,000 hours at 500 RPM. These loads and L, life ratings are minimum ratings for Goodman idlers. Actual values for load ratings and L, life for specific series and belt sizes may be higher. In some cases the idler frame design is the limiting factor for load with L, life being a higher value. Step 11 Determine idler bearing L,, life correction IL,, (CORRECTED) = L, (RATING) x K2 x K3A x K3B (IF APPLICABLE)] A) Effect of Load on Predicted Bearing L, Life (K2 Factor) When calculated idler load (CIL) is less than load rating of series idler selected, the bearing L, life will increase. Figure 1 shows this relationship for either a tapered roller bearing or a ball bearing idler design. This chart can be used in conjunction with the type of service or life expectancy of the conveyor system. If the specified design life of the conveyor system exceeds the L,, life rating at rated load it may still meet specification based on percent of rated idler load vs calculated idler load (CIL). Figure 1 K2 = Effect of Load on Predicted Bearing L,, LIFE SERIES B & BC BALL BEARING SERIES C, D & E TAPERED 2.0 ROLLER BEARING 1.o CIL (Calculated Idler Load) 1 Idler Load Rating (ILR) B) Effect of belt speed on predicted bearing L, life (K3A Factor) Goodman L, life ratings are based on 500 RPM. Slower speeds increase life and faster speeds decrease life. Figure 2 shows this relationship..j 18-BELT CONVEYOR IDLERS

16 Figure 2 K3a = Effect of Belt Speed on Predicted Bearing L,, Life C a 5.0 \ \ \ I K3A = I I 500 rpm Actual rpm I I - Roll Speed (RPM) RPM = Belt Speed (FPM) x 12 Roll Diameter (in.) x 7c The following table list belt speed at 500 RPM for standard roll diameters. I Roll Diameter (in.) I Belt Speed (FPM) 1 C) Effect of roll diameter on predicted bearing Llo life. (K3B Factor) For a given belt speed, using larger diameter rolls will increase idler Llo life. Figure 3 depicts Llo life adjustments for various roll diameters using 4" diameter as a value of 1.Om Percent life increase can be calculated for each roll diameter increase. NOTE: Factor K3B is an optional step showing advantage of using larger diameter rolls. It can be used as a multiplier to save repeating step 11 C if a larger diameter roll is used. Figure 3 K3B = Effect of Roll Diameter on Predicted Bearing L,, Life (Based on same belt speed) 1.75 b l.50-,7 c 8 LL !/ Roll Diameter (in.) Example:.5 for 6" diameter = 1 - or % increase in L,. life for 5 diameter NOTE: In addition to increased predicted bearing Llo life, larger diameter rolls can increase idler wear life. BELT CONVEYOR IDLERS-1 9

17 Step 12 Determine potential Idler Life due to effect of Environmental, Maintenance and Temperature. Factors K4A (Fig. 4), K4B (Fig. 5) and K4C (Fig. 6) Hostile environmental conditions and the level of commitment to the belt conveyor installation and maintenance will affect idler life. THESE CONDITIONS ARE INDEPENDENT OF IDLER LOAD, L,, LIFE AND IDLER CLASS but can cause idler failure before obtaining predicted L, life rating. These conditions do not have an exact mathematical basis and therefore can be very subjective. Goodman Conveyor Co. has vast application and belt conveyor idler design experience which can be used to identify the idler life condition for the application and then arrive at solutions to obtain maximum idler life for that application. Expected or potential idler life may also be limited by shell wear. Shell wear can vary considerably with each installation. In addition to conveyed material characteristics, environmental and maintenance factors, idler alignment and belt cleaning can have a significant affect on shell wear and idler life. Table 16 may assist in idler roll selection. Contact your Goodman Conveyor Co. representative for assistance and recommendations. 1.o Figure 4 K4A = Effect of Maintenance on Potential Idler Life GOOD FAIR POOR Qpe of Maintenance -BELT CONVEYOR IDLERS

18 Figure 5 K4B = Effect of Environmental Conditions on Potential Idler Life Environmental Conditions Figure 6 K4C = Effect of Operating Temperature on Potential Idler Life Temperature (degrees F) Table 16 - Idler Roll Recommendations BELT CONVEYOR IDLERS-21? o

19 ~ $&yl$$e~i& Step 13 Determine Goodman Conveyor ldler Specification and Model Numbers from Table and Guide Below Table 17 - ldler Specification Information , -<.,.* -,-;,..- ~orme$&xj&k ' - - Series B BC C BB None MD A B C C 'F&SCGE~A II None Ill & IV Sieries '.::' &:~i.bk.. 4&5 inch 4,5&6 inch 4,5&6 inch L. Type of Servick Light Duty Medium Duty Medium Duty D MDS D None 5&6 inch Medium to Heavy Duty E HD E V&VI 6&7 inch Heavy Duty MDG Same None None 5 & 6 inch Medium Duty E (Catenary) HD None None 6, 6 k, 7 & 7% inch Heavy to Extra Heavy Duty ldler ldentif ication Guide (Examples) Belt Width I(36" Wide' TTTTTT 36-C36A352-WB d r Shell Gau m Belt Widt.. Idler Gage (36" Wide) (Wide Base) ldler Series ( (SeriesC) No. of Rolls = Idler.Style = (2 oils) (Training) Roll Dia. Abbreviations Prefix (Series) Internal Suffix CQR-Catenary Quick Release B, BC, C, D, and E-(See Above) A-Impact D-Rubber Disc CC-Catenary Chain SL-Sealed For Life T-Training E-Elastomer (Urethane) CRK-Catenary Rod & Key X-Special Feature SQ-Scale Quality L-Live Shaft CEH-Catenary Eye Hook MDG-Medium Duty Grain SS-Scale Service M-Massed End WB-Wide Base 22-BELT CONVEYOR IDLERS Note: Standard Base is furnished unless Wide Base (WB) is specified.

20 Appendix Table 18-1 Troughing ge Weight (L Rotating Pa 3s.) of ts-steel Rolls Table 19-Average Weight (Lbs.) of Return Idler Rotating Parts-Steel Rolls Table -WK2 (Lb.-ln.2) Average for Three Equal Roll Troughing Idlers Table 21 -WK2(Lb.-ln.2) Average for Single Steel Return Idlers BELT CONVEYOR IDLERS-23