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Rexnord 1874, Инструкция по эксплуатации

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Wear Strip Material Selection

Proper chain and wear strip selection will provide 
optimum chain and wear strip life. Friction and wear 
resistance are two factors which should be considered 
when selecting a wear strip material.

1. The lower the coefficient of friction between the chain  
and wear strip, the longer the chain life.

2. The greater the wear resistance of the chain and wear 
strip materials, the longer the chain life and wear strip 
life.

Of course, the combination of chain tension, top load, 
type of lubrication, abrasion, and speed of a given 
conveyor will govern the final wear rate of a particular 
chain-wear strip combination. The worst condition is high 
speed, dry operation.

Rexnord has accumulated many years of application 
experience as well as laboratory test data on chain-wear 
strip compatibility. The following general guideline will 
help in the selection wear strip materials.

Metal Wear Strips

Metal  wear strips are harder than non-metallics, and in 
addition can be heat treated or work hardened to 
increase hardness. They are, therefore, suited for 
applications where abrasive particles are present either 
from the environment or from the products carried. 
Abrasive particles are less likely to embed in metal wear 
strips. 

For non-corrosive environments, plain carbon steel , cold 
finished, is recommended. For corrosive environments, 
use stainless steel, one quarter temper minimum (25 Rc), 
cold finish.

SELECTION PROCEDURE

Application Information

If properly selected and applied, chain will wear out in 
service before it breaks from fatigue.

Selection of the proper chain for a specific application 
requires that all of the following information be known:

· Conveyor length
· Conveyor width
· Wear track material
· Top load (weight per square foot or weight per square  
  meter)
· Chain speed (feet per minute or meters per minute)
· Operating conditions (dry or lubricated)
· Environment (abrasiveness, temperature, chemical   
  activity, etc.)
· Accumulation requirements (slippage)
· Attachments required
· Type of transfer plate

Chain Material Selection

Besides temperature and strength factors, ir is important 
to consider chemical, wear and impact resistance.

Chemical resistance should be considered for 
applications where bleach, acid, etc. are present. HT and 
LT materials have the best chemical resistance. Always 
consult the chemical resistance chart (Page 4, MatTop®) 
or Rexnord if unsure about material - chemical 
compatibility. Consider pin material resistance, too.

Impact resistance can be obtained from the LT material. 
Moderate to severe impacts are easily handled by LT 
whereas LF and HT materials offer small to moderate 
resistance.

SELECTION

PROCEDURE

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MatT

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Chains

MT-1                                                                                                                                                           Rex

®

Engineering Manual   

Содержание 1874

Страница 1: ... Rex Engineering Manual ...

Страница 2: ...Rex TableTop Engineering Manual ...

Страница 3: ...ndant machinery including dead plates and turntables The criteria for conveyor width and speed is the number of products which must be delivered to a location per unit of time The infeed and outfeed of each process machine will dictate product flow width at the machines But in between the alternatives range from high speed single file to intermediate speed multiple file on one wide chain to slow s...

Страница 4: ...iary means of transferring around corners such as the dead plate and turntable shown below The illustration on this page shows the basics of a simple straight running conveyor There are many variations on this design so Rexnord Engineers are available to assist and make recommendations for any TableTop application Guide clearance space between wear strips for proper chain tracking At sprocket chai...

Страница 5: ...the need for corner transfers turntables dead plates and attendant machinery Rex sideflexing conveyor chains solve those conveyor problems where high speed transfers of product was once a hazardous risk at best where mass handling to single line conveying was a perplexing problem where plant layout was sacrificed for lack of design flexibility The illustration below shows the basics of a simple si...

Страница 6: ... straight and curve are shown on individual chain listing pages STRAIGHT RUNS For straight running sideflexing Bevel Tab chains SLIDING RETURN WAY ROLLER SERPENTINE STYLE RETURN WAY MOUNTING BRACKET INSIDE OF TURN CORNERS BEVELED CHAIN OF TURN MULTIPLE STRAND CORNERS TYPICAL TAB CHAIN MINIMUM CLEARANCE GC CURVE INSIDE TURN TYPICAL INSIDE OF TURN Note Dimensions subject to change Certified dimensio...

Страница 7: ... ordered material furnished on request 1 MIN SIDEFLEXING SIDEFLEXING Style Style GC GC STRAIGHT GC CURVE GC STRAIGHT GC CURVE CORNER WEAR STRIPS CORNER WEAR STRIPS 1 MIN 1 MIN 1 MIN 1 MIN INSIDE OF TURN 1 8 MINIMUM CLEARANCE 1 4 MINIMUM CLEARANCE Guide clearances straight and curve are shown on individual chain CARRYING WAYS Rex TableTop Chains Rex Engineering Manual TT 5 ...

Страница 8: ...r smoothest operation the dead plate should be mounted so that it is perfectly aligned with or slightly higher than the top surface of the outfeed chain at the highest chordal position of the sprocket It should have a slight bevel and be as narrow as possible so that the product conveyed transfers on and off the dead plate without obstruction Flexible dead plates can float with the chordal action ...

Страница 9: ...ugh away from the head sprocket to allow for proper catenary sag dimension A should be greater than the distance between rollers B The preferred diameter of rollers should be at least two times greater than the minimum backflex radius for the chain Refer to table Minimum Backflex Radii For example when used with 820 Series chains roller diameter should be 3 inches or greater Roller and support sho...

Страница 10: ...0 821 831 963 864 879 880 881 882 1873 1874 3873 LBP821 LBP882 LBP883 The idler wheel can be used in place of tail sprockets on TableTop one piece link chain conveyors only They are made of an engineering plastic material are self lubricating and are resistant to most chemical solutions and corrosive environments In existing conveyors the idler wheel can be installed with only minor conveyor adjus...

Страница 11: ...et to the end of the wear track Transfer Plate Positioning Dimension C is the dimension from the centerline of the sprocket to the top of the transfer plate C A 7 5 0 1 32 C A B 1 1 2 2 2 4 20 24 MINIMUM ENTRY RADIUS R Chain No In mm R LBP821 LBP882 TAB LBP883 16 9 2 406 229 51 FULL WIDTH SLIDING RETURN FOR USE WITH LBP821 LBP882 TAB OR LBP883 TAB SERPENTINE STYLE RETURN FOR WITH LBP821 LBP882 TAB...

Страница 12: ...the sprocket tooth particularly under high peak loads Contact Rexnord Corp for additional comments OFFSET WRAP DRIVE Unlike a tangential drive this approach is limited to chains having sideflexing capability Essentially the unabsorbed chain tension as well as excess chain at the drive sprocket is compensated for by a catenary The chain the engages an idler tail sprocket or wheel and then continues...

Страница 13: ...Rex MatTop Engineering Manual ...

Страница 14: ...s For non corrosive environments plain carbon steel cold finished is recommended For corrosive environments use stainless steel one quarter temper minimum 25 Rc cold finish SELECTION PROCEDURE Application Information If properly selected and applied chain will wear out in service before it breaks from fatigue Selection of the proper chain for a specific application requires that all of the followi...

Страница 15: ...ant at austenitic BRONZE AND BRASSES A hard temper material is recommended since a soft bronze wears rapidly Typical applications calling for these metals are those which require non sparking and anti static conditions These materials are generally not recommended ALUMINUM Not recommended due to poor wear resistance NON METALLIC WEAR STRIPS Non metallic wear strips have a lower coefficient of fric...

Страница 16: ...mation Sprocket and Bore Style Selection Choose the largest sprocket pitch diameter possible since this will give the greatest chain life Larger pitch diameter sprockets cause less chain articulation thus producing less pin joint wear High speed conveyors are applications where larger pitch diameter sprockets are desired High load applications should also favor larger pitch diameter sprockets beca...

Страница 17: ...Citric Acid Cyclohexane Ethyl Chloride Formaldehyde Formic Acid Fruit Juices Gasoline Hexane Hydrochloric Acid up to 2 Hydrochloric Acid up to 37 Hydrogen Peroxide Iodine Isopropanol isopropyl alcohol Kepodene Lactic Acid Methylene Chloride Milk Muriatic Acid Nitric Acid low concentrations Oil vegetable or mineral Paraffin Phosphoric Acid up to 10 Soap and Water Sodium Chloride Sodium Hydroxide up...

Страница 18: ...T Polyethylene HT Polyethylene Solid and Perforated Top Solid and Perforated Top Solid and Perforated Top Raised Top Raised Top Raised Top Solid and Perforated Top 0 20 0 18 0 15 0 18 0 14 0 10 0 18 0 16 0 14 0 22 0 19 0 15 0 19 0 16 0 12 0 30 0 25 0 20 0 24 0 20 0 16 0 30 0 22 0 25 0 30 0 25 0 35 0 28 0 25 0 20 0 15 0 10 0 16 0 14 0 10 0 08 0 18 0 16 0 13 0 10 0 28 0 22 0 15 0 10 0 25 0 18 0 12 0...

Страница 19: ... 30 30 50 Over 50 TABLE 4 STANDARD CONVEYOR GUIDE CLEARANCE Calculation of GC at Elevated Temperatures Assume a 12ft wide 45 ft lone pasteurizer operating at an average temperature of 190 F 1 The increase in the width W due to the temperature of 190 can be found as shown W W chain width in Ft or m x CThermal Expansion x T Temp diff from room temp of 70 F 21 C W 12 ft x 0 001 in x 190 F 70 F Ft F W...

Страница 20: ... CHAIN CHAIN WIDTH Figure 11 Cheveron or Herring Bone Figure 13 Roller Supports NOTE The rollers must be rigid enough to resist deflection Roller beds are not suitable for all chains or applica tions Contact Rexnord for additional information 3 4 Pitch Chains 1 1 2 Pitch Chains 2 1 4 Pitch Chains DRef 1 1 2 SRef 1 5 8 DRef 2 SRef 2 1 8 DRef 2 1 2 SRef 2 5 8 6 TYP 2 TYP CHAIN WIDTH C CF L 6 T Y P 2...

Страница 21: ...OTE The supports shown in the carry way section may also be used for return way supports Return Way Supports chain with attachments CHAIN WIDTH Thermoplastic 1 1 2 MIN 6 MIN 1 1 2 MIN 6 MIN Figure 16 Serpentine Plastic Extrusions or Metal Rod SELECTION PROCEDURE cont Conveyor Design and Construction Rex MatTop Chains Rex Engineering Manual MT 8 ...

Страница 22: ...a catenary is not practical i e conveyors that are vertical or tilted to the side 90 from horizontal adjustment of shaft perpendicularity to maintain proper chain tracking When a take up or tensioning device is required to keep a chain under constant tension Rexnord recommends that a spring loaded or similar tensioner be used Premature failure may result from an over tensioned chain NOTE The follo...

Страница 23: ...s mm 2100 4705 5705 4706 5706 4707 5935 5936 6938 5966 5995 5996 5997 6085 1 1 1 2 1 1 2 2 1 1 1 2 1 1 2 2 3 4 2 25 38 38 51 25 38 38 70 51 TABLE 5 MINIMUM BACKFLEX RADIUS Figure 22 Conveyors with up to 60 centers and top load up to 20 lbs sq ft Figure 21 Conveyors with up to 40 centers and top load up to 15 lbs sq ft Figure 23 Conveyors with longer than 60 centers and top load in excess of 20 lbs...

Страница 24: ...ine with support tracks C O D 2 2 A t 0 125 2 D Figure 25 Standard transfer plate mounting TABLE 6 FLAT TRANSFER PLATE MOUNTING DIMENSIONS PD pitch diameter HEAD AND TAIL END CONSTRUCTION dimensions A C Transfer plate positioning head and tail Dimension A is the dimension from the centerline of the sprocket to the top of the wear track Dimension B is the dimension from the centerline of the sprock...

Страница 25: ...36 9 1 2 2 3 25 82 6 3 25 82 6 1 50 38 1 2 25 57 2 PD 0 50 12 7 PD 0 61 15 5 2 2 0 25 6 4 0 25 6 4 TABLE 7 COMB TRANSFER PLATE MOUNTING DIMENSIONS NOTE TOLERANCES A 0 1 32 0 80 C 0 1 4 6 35 D 1 32 0 80 0 NOTE B dimension is flexible One must insure that comb figures extend beyond sprocket centerline to avoid transfer problems Mounting sprockets in line with wear strips is not recommended for chain...

Страница 26: ...er most transfer plates as shown These will track the chain 2 On transfer plates to the left of center position fasteners to the left side of the slot On the right hand transfer plates position fasteners to the right side of the slot This arrangement will allow these transfer plates to move as required to accommodate changes in chain width up to 1 1 2 38 1 For Room Temperature Applications 1 Secur...

Страница 27: ...92 1 8 5 40 2 4 7 20 3 2 9 60 4 1 12 30 5 3 15 90 6 6 19 70 8 0 23 90 9 7 29 00 11 5 34 40 13 5 40 40 3 0 75 4 0 100 5 0 125 6 0 150 7 0 175 8 0 200 9 0 225 10 0 250 12 0 300 TABLE 8 T CATENARY TENSION POUNDS NEWTONS FOR CHAIN WEIGHING ONE POUND PER FOOT2 OR ONE KILOGRAM PER METER2 The end drive method is recommended for light duty service 10 20 centers on conveyors where the chain tension on the ...

Страница 28: ... sprockets per foot 13 per meter of chain width 5935 5936 2100 AND 6938 CHAINS Use 4 sprockets per foot 13 per meter of chain width for loads up to 50 of chain capacity and 6 per foot 20 per meter for loading in the 50 75 capacity range Loading of more than 75 of the chain s capacity requires 8 sprockets per foot 26 per meter of chain width 5966 5995 AND 5996 CHAINS Use 2 sprockets per foot 7 per ...

Страница 29: ...N4700 and N5700 Sprockets Figure 32 Figure 33 Figure 31 For molded to width sizes or chains not shown contact Rexnord 2 1 2 2 1 2 C L 820 SPROCKET C L 820 SPROCKET 12 WIDTH 3 3 12 WIDTH C L 820 DOUBLE SPROCKET C L 820 DOUBLE SPROCKET 12 WIDTH C L SPROCKET 4700 C L SPROCKET 4700 3 3 SELECTION PROCEDURE cont Sprocket Requirements and Location cont Rex MatTop Chains Rex Engineering Manual MT 16 ...

Страница 30: ...ains 5996 and 5997 Chains 3 4 1 1 2 1 1 2 1 1 2 1 1 2 1 1 2 1 1 2 1 1 2 3 4 C L SPROCKET POCKET 12 WIDTH 12 WIDTH 1 1 2 3 3 3 1 1 2 C L SPROCKET POCKET C L SPROCKET POCKET 1 1 4 3 1 2 2 1 2 3 1 2 1 1 4 C L SPROCKET POCKET 12 WIDTH SELECTION PROCEDURE cont Sprocket Requirements and Location cont Rex MatTop Chains MT 17 Rex Engineering Manual ...

Страница 31: ... see general note below Use square or hex bore sprockets on conveyors intended for use at elevated or lower temperatures warmers pasteurizers coolers etc When installing the sprockets make sure that all sprocket faces are positioned the same way on the shaft with identification marks all facing the same direction as shown Also be sure to align the notched teeth for proper timing GENERAL NOTE It is...

Страница 32: ... HT LT 11 31 32 11 31 32 11 31 32 23 31 32 23 15 16 23 29 32 35 15 16 35 27 32 35 7 8 47 29 32 47 27 32 47 13 16 59 27 32 59 27 32 59 25 32 303 9 303 9 303 9 608 8 607 9 607 2 912 8 910 4 911 2 1216 8 1215 2 1214 4 1520 0 1520 0 1518 4 5995 5995 ACTUAL WIDTH INCHES ACTUAL WIDTH MILLIMETERS WSM LT WSM LT 12 1 32 12 1 32 24 1 16 24 1 16 36 3 32 36 3 32 47 1 8 47 1 8 60 5 32 60 5 32 305 6 305 6 611 2...

Страница 33: ...g links 2 Replace links as required and replace all pins that were removed with new pins 3 Using a soldering iron to form a pin head so that the head is recessed in the end of the link A special tip for standard soldering irons is available from Rexnord Contact your sales representative or distributor for details Rexnord provides the soldering iron tips at a nominal cost A 40 watt to 80 watt solde...

Страница 34: ... help pull chain together during final assembly when the last pin in inserted The assembly tool works with 4706 5996 and 5997 chains Contact MatTop Customer Service for pricing and delivery 1 Pry pin lock insert out with screwdriver 2 Turn the screw starter sheet metal screw etc into plastic pin 3 Pull out plastic pin Remove or add links as needed Reinstall pin and pin lock insert Replacement 5900...

Страница 35: ...Rex Multiflex Engineering Manual ...

Страница 36: ...sliding curves can be used for any corner turn The chain supporting members chain guides and product guide rails for corners are similar to those used in the straight sections The corner sections of the conveyor provide full chain support The corner discs are positioned in such a manner that the chain while being engaged with the disc is also being supported by the wear strips The chain guides are...

Страница 37: ...n WHEN DECLINING the chain must pass through a transition zone only after it has left the disc The disc should be tipped to lie in the same plane as the entering chain Also provide for minimum spacing D for the leaving chain Note In the transition zone the wear strips should be curved to accomplish smooth transition from one plane of conveying to the next CORNER DISC C L D Not This Any change in a...

Страница 38: ...he flexibility of Multiflex chains permits the use of several types of transfer 1 FT Recommended Minimum 1 FT Recommended Minimum Side Transfer Where Product Moves in Straight Line Side Transfer Where Product Moves Laterally from Chain to Chain 1 FT Recommended Minimum Cross Transfer Where Product Can Flow Straight fro Chain to Chain or Remain on Same Chain Using Switches Corner Transfer Where Pro...

Страница 39: ...es not have a flange to contain the chain then the conveyor frame must have a skirt to track the chain on the wheel CONVENTIONAL CONVEYORS If the Multiflex chain is used to convey in one plane a conventional return might be used as shown IDLER WHEEL FOR TAIL WHEEL See Note 2 For Mounting details see Page 8 Multiflex NOTE RETURN CHAIN FOLLOWS SAME PATH AS CARRYING CHAIN ON CONVEYOR Page 6 Multiflex...

Страница 40: ...ENARY See Page 7 Multiflex drive Rex Multiflex chains have the ability to elevate or lower products in a very compact area This figure shows a typical elevating system and how the chain is being returned on such a unit Note that the chain hangs straight down from the drive sprocket and side flexes back up into the tail section there is no sliding return Elevators can also be designed with combined...

Страница 41: ...yors sliding returns are recommended not roller returns The straight corner section design for the sliding return can be the same as for the carry section The chain is simply run in the conveyor upside down through the return section 4 Multiflex MULTIFLEX CHAIN ENGINEERING TYPICAL CONVEYOR CONSTRUCTION Rex Multiflex Chains Rex Engineering Manual MF 6 ...

Страница 42: ...ION OF CATENARY LENGTH Lowering System TAIL SHAFT HEAD CATENARY LENGTH ALTERNATE CATENARY ARRANGEMENTS If the recommended length of chain in the catenary cannot be maintained because of space limitations etc increase the chain wrap to by use of an idler wheel as shown With an idler wheel arrangement the catenary chain length only needs to be of that listed in the above table Head Sprocket With an ...

Страница 43: ...1 575 3 0 Only B values same as above LOCATION AND POSITIONING STRIP TOP OF AR STRIP TOP OF WEAR STRIP IDLER WHEEL A Pitch Diameter C 2 WEAR STRIP B A 1 32 0 50mm 40mm 76mm 15 32 1 4 45 64 2 TOP OF WEAR STRIP WEAR STRIP B A 1 32 0 MULTIFLEX CHAIN ENGINEERING SPROCKET IDLER POSITIONING Rex Multiflex Chains Rex Engineering Manual MF 8 ...

Страница 44: ...ction Factors Between Chain and Wearstrips Fw Friction Factors Between Product and Wearstrips Fm D Acetal Stainless Steel Dry Water Soap Water Dry Dry Water Soap Water Oil Dry Water Soap Water Dry Water Soap Water Dry Water Soap Water Dry Water Soap Water 0 25 0 20 0 15 0 33 0 30 0 22 0 15 0 10 0 25 0 17 0 12 0 20 0 15 0 10 0 27 0 18 0 14 0 20 0 15 0 10 0 20 0 18 0 15 0 30 0 25 0 20 0 15 0 10 0 20...

Страница 45: ...eight Lbs Ft fw Coefficient of Friction Chain Tension Lbs 1 x 2 x 3 Chain Tension into The Turn Lbs 4 Prev 7 Turn Factor TF 1 15 TF Used For The Section Lbs 5 x 6 No TF Used For The Section Lbs 4 Prev 7 Chain Tension Slip 4 Slip 3 1 2 3 4 5 6 7 Tr Tension in Return Section Tc Ts Tension in Carry Section Slippage 120 2 CT 58 3 1 2 3 4 5 6 7 Conveyor Section L Section Length Ft W M Chain Product Wei...

Страница 46: ...ction Length Ft W M Chain Product Weight Lbs Ft fw Coefficient of Friction Chain Tension Lbs 1 x 2 x 3 Chain Tension into The Turn Lbs 4 Prev 7 Turn Factor TF 1 15 TF Used For The Section Lbs 5 x 6 No TF Used For The Section Lbs 4 Prev 7 Chain Tension 1 2 3 4 5 6 7 For Slip only use M For Slip use fm 404 0 x 1 0 13 3 10 10 10 10 10 2 10 10 13 13 7 85 7 85 7 85 7 85 7 85 7 85 7 85 7 0 7 85 7 0 7 85...

Страница 47: ...sidered i e stress corrosion cracking corrosion etc Temperature shown in indicate temperature to which material may be subjected for brief intermittent periods For example chains can be steam cleaned but caution should be used to avoid continuous exposure S881 SS881 1874 and 1874SS Whenever possible lubrication should be used to assure maximum chain life and optimum conveyor operation Types of lub...

Страница 48: ...c Acid Cyclohexane Ethyl Chloride Formaldehyde Formic Acid Fruit Juices Gasoline Hexane Hydrochloric Acid up to 2 Hydrochloric Acid up to 37 Hydrogen Peroxide Iodine Isopropanol isopropyl alcohol Kepodene Lactic Acid Methylene Chloride Milk Muriatic Acid Nitric Acid low concentrations Oil vegetable or mineral Paraffin Phosphoric Acid up to 10 Soap and Water Sodium Chloride Sodium Hydroxide up to 2...

Страница 49: ...on 1 2 lb 1 lb 2 lb Milk Cottage Cheese Paper Paper 3 x 3 3 x 3 3 1 8 x 3 1 8 4 1 8 x 4 1 8 6 x 6 0 6 1 1 2 3 4 5 8 8 0 6 1 1 2 3 4 Dia 4 3 4 Dia 5 Dia Weights and sizes will vary consult Rexnord Inc for assistance in selection 12 oz Regular Junior 10 1 2 oz Meat Baby Food Soup Metal Glass Metal 3 7 8 x 2 1 8 Rect 2 3 8 Dia 2 3 8 Dia 0 94 0 56 0 8 0 8 12 oz 22 oz 32 oz Quart 1 2 Gallon Gallon Soap...

Страница 50: ...hibits only slight wear Therefore ONE QUARTER TEMPER MINIMUM 25 Rc austenitic grade stainless is recommended for use with any of the chain materials but especially with thermoplastic Martensitic stainless steels can also be used They offer excellent wear resistance when heat treated to 25 35 Rc but they are not as corrosion resistant as austenitic BRONZE AND BRASSES These materials are sometimes u...

Страница 51: ...erial is still based on top plate and product compatibility Then non metallic wear strips might be used if the chain flight is steel or stainless steel Or if the chain flight material is thermoplastic steel or stainless steel wear strips are used CHAIN FLIGHT AND WEAR STRIP MATERIALS RECOMMENDED CHAINS AND WEAR STRIPS STRAIGHT RUN SIDEFLEXING THERMOPLASTIC STEEL STAINLESS STEEL WEAR STRIP MATERIAL...

Страница 52: ... wear life of chain and wear strips Be sure the lubricant coats both the chain and wear strip mating surfaces This is especially important on sideflexing chains and it is sometimes necessary to apply the lubricant at the entrance of the inside curves If lubrication is not compatible with the application a brief break in lubrication application is beneficial Apply a light mineral oil to sideflexing...

Страница 53: ...ets for signs of excessive wear 7 Examine sprockets for signs of dirt build up in tooth pockets 8 Check for sprocket guide ring wear and possible chain misalignment 9 Check the ways and wear strips for excessive wear 10 Inspect lubrication system for proper operation 11 Check the inside of curves and the supporting conveyor frame for excess heat build up which may indicate an obstruction in the cu...

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