CEMA Standard No. 404 · 2019-06-11 · outboard bearings. In a chain driven live roller conveyor, rollers are powered via sprockets attached to either or both ends of the roller

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ANSI / CEMA 404-2003 (R-2015) Reaffirmation of ANSI/CEMA 404-2003

Approved: January, 2015

CEMA Standard No. 404

Conveyor Equipment Manufacturers Association

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ANSI/CEMA Standard No. 404-2003 (R‐2015) – Chain Driven Live Roller Conveyors- Unit Handling Conveyors

II

DISCLAIMER The information provided herein in advisory only. These recommendations provided by CEMA are general in nature and are not intended as a substitute for professional advice. Users should seek the advice, supervision and/or consultation of qualified engineers, safety consultants, and other qualified professionals. Any use of this publication, or any information contained herein, or any other CEMA publication is made with agreement and understanding that the user and the user’s company assume full responsibility for the designs, safety, specifications, suitability and adequacy of any conveyor system, system component, mechanical or electrical device designed or manufactured using this information. The user and user’s company understand and agree that CEMA, its member companies, its officers, agents and employees are not and shall not be liable in any manner under any theory of liability to anyone for reliance on or use of these recommendations. The user and the user’s companies agree to release, hold harmless and indemnify and defend CEMA, its member companies, successors, assigns, officers, agents and employees from any and all claims of liability, costs, fees (including attorney’s fees), or damages arising in any way out of the use of this information. CEMA and its member companies, successors, assigns, officers, agents and employees make no representations or warranties whatsoever, either expressed or implied, about the information contained herein, including, but not limited to, representations or warranties that the information and recommendations contained herein conform to any federal, state or local laws, regulations, guidelines or ordinances.

Conveyor Equipment Manufacturers Association 5672 Strand Ct., Suite 2

Naples, Florida 34110-3314 www.cemanet.org Copyright © 2015

http://www.cemanet.org/

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III

FOREWORD Chain driven live roller conveyors are used for the controlled movement of a great variety of regular or irregular shaped commodities, from light and fragile to heavy and rugged unit loads. The path is usually level, but it can be slightly inclined or declined, limited by the coefficient of friction between the rollers and the load. Chain driven live roller conveyors are used for transportation, as a pacesetter for assembly operation, and as a timing medium for integrated handling systems. The purpose of this standard is to establish recommended minimum standards for use in the design and application of chain driven live roller conveyors. For additional information relating to definitions and selection of common components, see latest edition of the following publications: ANSI/CEMA Standard No. 401, Roller Conveyors-Non Powered; ANSI/CEMA Standard No. 402, Belt Conveyors; ANSI/CEMA Standard No. 403, Belt Driven Live Roller Conveyors; and ANSI/CEMA Standard No. 102, Conveyor Terms and Definitions. The illustrations throughout this book are schematic in nature and represent the general nature of a particular device. The illustrations are not intended to represent the recommended safety configurations since guarding has been omitted to permit clarity in showing the operational characteristics of the device. Refer to the current editions of ANSI/ASME B20.1, Safety Standard for Conveyors and Related Equipment; ANSI/ASME B15.1, Safety Standard for Mechanical Power Transmission Apparatus; and ANSI Z244.1, American National Safety Standards for Lock-out/Tag-out of Energy Sources - Minimum Safety Requirements; Title 29, Code of Federal Regulations (29 C.F.R.) Part 1910.147, the control of hazardous energy (lock-out/tag-out); Title 29, Code of Federal Regulations (29 C.F.R.) Part 1910 Subpart O, Machinery and Machine Guarding. Consult ASME or ANSI for the latest editions. In 2003 Edition, include Safety Label Requirements Notice here, Terms and Definitions have been expanded, regrouped for ease of understanding, and revised to conform with those in ANSI/CEMA Standard No. 102, Conveyor Terms and Definitions. On section 2, Figures have been redrawn and, in some cases, regrouped for clarity.

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IV

TABLE OF CONTENTS

Page Sections

1 Definitions 1 Chain Driven Live Roller 1 Roll-to-Roll Type 1 Continuous Chain Type 1 Mechanical Elements of Chain Driven Live Roller 1 2 Applications 3 General Application Engineering Data 3 Roll-to-Roll Construction 4 Continuous Chain Construction 4 Live Shaft Construction 5 Chain Driven Live Roller Curves 5 Transfers 5 Accumulating Chain Driven Live Roller 6 Roll-to-Roll Chain Driven Live Roller Conveyor 7 Continuous Chain Driven Live Roller Conveyor 10 Transfer Selection Data 14 3 Technical Data 15 Symbols 15 Metric conversion 15 Chain Pull and Horsepower Calculations 16 Minimum roller centers 19

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SAFETY NOTICE The Conveyor Equipment Manufacturers Association has developed Industry Standard Safety Labels for use on the conveying equipment of its member companies. The purpose of the labels is to identify common and uncommon hazards, conditions, and unsafe practices which can injure, or cause the death of, the unwary or inattentive person who is working at or around conveying equipment. The labels are available for sale to member companies and non-member companies. A full description of the labels, their purpose, and guidelines on where to place the labels on typical equipment, has been published in CEMA’s Safety Label Brochure No. 201. The Brochure is available for purchase by members and non-members of the Association. Safety Labels and Safety Label Placement Guidelines, originally published in the Brochure, are also available free on the CEMA Website. Please Note: Should any of the safety labels supplied by the equipment manufacturer become unreadable for any reason, the equipment USER is then responsible for replacement and location of these safety labels. Replacement labels and placement guidelines can be obtained by contacting your equipment supplier or CEMA.

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SECTION 1 - DEFINITIONS Chain Driven Live Roller - Conveyors which use a roller bed for the carrying surface. The unit loads ride directly upon the roller surfaces, and the rollers are driven by chains and sprockets. Roll-to-Roll Type - A chain driven live roller conveyor in which power is transmitted from roll to roll via short chain loops, each of which encircles the sprocket attached to the adjacent driven rollers, causing each to rotate. Two sprockets are required for each driven roller. (See Figures 1 through 7) Continuous Chain Type - A chain driven live roller conveyor driven by one continuous strand or loop of chain, engaging a sprocket attached to each driven roller, causing the roller to rotate. One sprocket is required for each driven roller. (See Figures 8 trough 15) Mechanical Elements of Chain Driven Live Roller

• Chain - A series of links pivotally joined together to form a medium for conveying or transmitting motion or power.

− Riveted - A chain in which the ends of the pins are “headed” and/or swagged or riveted so that the chain cannot be disassembled without cuffing off the pin.

− Roller - A chain having a roller encircling the barrel or bushing of each joint. − Tension - The actual pull existing at any point in a chain. − Link - A chain unit of one pitched length.

• Conveyor Bed - Carrying rollers that support the load while it is being conveyed (see also

“Width, Effective Conveyor”)

• Differential Curve - A curved section of roller conveyor having a conveying surface of two or more concentric rows of rollers.

• Drive - An assembly of the necessary structural, mechanical and electrical parts which

provide the motive power for a conveyor.

• Frame Rails - Members that support the conveying components of non-powered or powered roller conveyors. Rollers are the supported components on roller conveyors.

• Guard - A covering or barricade for safety purposes such as gear, chain, or nip guards.

• Holddown - A wear-member located over the driving (top) side of chain and sprockets to

prevent chain disengagement from the sprocket teeth. Used on continuous chain construction chain driven live roller conveyor.

• Horizontal Curve - A curved roller conveyor section used to change the direction of travel.

• Idler - A pulley, sheave, sprocket, or wheel around which a chain passes in changing

direction of travel; chain-supporting sprocket.

• Intermediate Drive - A drive that transmits motive power to a conveyor at a point other than the terminals.

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• Live Roller Conveyor - A series of rollers over which objects are moved by the application of power to all or some of the rollers.

• Plates, Fill-in - Closely fitted plates positioned between the rollers of powered or non-

powered roller conveyors.

• Return Run - That portion of the chain which returns from the discharge to the loading end of a conveyor.

• Return Track - A track supporting the conveying medium (chain) on the return run.

• Roller - A round part free to revolve its outer surface. The face may be straight, tapered,

crowned, concave or flanged, corrugated, ribbed or fluted. Typically, a cylindrical member with internal bearings mounted on a non-rotating shaft. Rollers can have live shafts and outboard bearings. In a chain driven live roller conveyor, rollers are powered via sprockets attached to either or both ends of the roller or live shaft.

− Carrying - The conveyor roller upon which the object being transported is supported.

− Driven - Any carrying roller driven by chain or other propelling medium. − Idler - Any carrying roller of a live roller conveyor which is not driven. − Tapered - A conical conveyor roller for use in a curve with end and intermediate

diameters proportional to their distance from the center-point of the curve.

• Sprocket - A wheel with suitably shaped and spaced cogs, or teeth, to engage with the links of a chain

− Driven - A sprocket propelled by the chain. − Return Idler - A sprocket that supports the return run of the chain.

• Take-up - The assembly of the necessary structural and mechanical parts which provides

means to compensate for stretch, or wear, and to maintain proper chain tension. Adjustment is usually manual and is employed on continuous chain driven live roller construction only.

• Transfer Medium - Any mechanism that transfers objects onto or off a conveyor line or from one conveyor line to another.

• Wearing Bar - A bar attached to a track or trough which may be replaced when worn, thus

protecting the main members (chain) from damage due to wear.

• Width, Effective Conveyor - The clear dimension across the conveyor bed and parallel to the carrying rollers where the unit load may be conveyed; on chain driven live roller conveyor, the dimension between side rail and chain cover plate.

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SECTION 2 – APPLICATIONS General Application Engineering Data Chain driven live roller conveyors are used to carry loads with a flat, smooth, and firm bottom riding surface at controlled speeds. They are better suited than belt driven live roller conveyors in applications where heat, dirt, oil, water, and other contaminants are present. Chain driven live roller conveyors are ideal for carrying heavy or bulky loads. Conveyors may be spring mounted to absorb shock when being loaded or unloaded with heavy unit loads. They are ideal conveyors when the application requires right angle transfers, such as disappearing chain transfers, push-on or push-off transfers, or converging sections. This construction is commonly used for the carrying bed of transfer cars, for powered beds in rollovers, up enders, dump units, turntables, and vertical reciprocating conveyors. Two sections of chain driven live roller may be tilted to form V-trough construction for handling cylindrical loads. Since power is transmitted to the carrying bed rollers by chain and sprockets, unit loads are always positively driven at a controlled speed. These conveyors work best when they are installed horizontally; however, depending on the unit load handled, they may be slightly inclined or declined. Several conveyors may be assembled in a line, and by controlling each conveyor, they can accumulate loads at zero storage line pressure by “cascading”, holding one load on each conveyor. Chain driven live roller conveyor may also be designed to accumulate loads by “indexing” or start-stop operation, resulting in zero storage line pressure between loads. Electric controls are provided at the receiving end of the conveyor to allow a load to index forward onto the conveyor approximately one load length, then shutting down the conveyor. This indexing operation is repeated until the conveyor is filled. The entire train of accumulated loads is then indexed, leaving an empty conveyor so the indexing cycle may be repeated. A combination of previously described “cascade” and “indexing” operations may also be used to provide accumulation at zero storage line pressure. Ideally, three (3) rollers should be under the load at all times. Occasionally, two (2) rollers will be sufficient, depending on the unit load (product) handled. Carrying rollers are normally spaced 4" to 12" on centers. For centerlines between rollers greater than 12", considerations may be required to compensate for chain sag between the rollers. Conveyors are normally run at speeds between 30 and 60 fpm; however, greater or lesser speeds may be used. For greater speeds, precision bearings and/or chain lubrication may be required. Chains and sprockets must be guarded. Fill-in plates may be added between the carrying rollers to assure that the leading edge of a unit load will ride on the carrying roller and not sag between rollers.

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There are many variations in drive arrangements. A common practice is to use a gear motor with output shaft connected by loop chain drive to the sprocket(s) on the drive roll(s). Another option is the use of shaft mounted reducers. When variable speed is required, a mechanical speed changer between the motor and reducer may be used. Electrically, the speed may be changed using variable frequency drives. Close center roller construction must have all rollers driven. If all rollers are not positively driven, in-running nip points are created at every roller to roller interface. Roll-To-Roll Construction (Figures 1 trough 7) In this type construction, two plate sprockets are attached to each roller, and individual loops of chain connect pairs of rollers in a staggered pattern along the length of conveyor. This construction is ideal for handling heavy loads and for applications requiring frequent stopping or reversing service. It is ideal for low elevation applications, with the driving unit mounted beside or above the conveyor frame. For very wide loads, two conveyors may be set side-by-side (referred to as “two-lane, four-rail” construction) having a countershaft with loop chain drive from each lane and driven from one drive unit through the countershaft. “Two-lane, three-rail” construction may also be used, where a common mid-rail acts as the frame for adjacent conveyor beds. Normal construction calls for the chain and sprocket cover guard to extend above the carrying surface of the rolls. However, large diameter sleeves may be attached to the driven rollers to provide carrying surface above chain cover guard. It is recommended that the drive be located near the center of the conveyor length to keep the chain pull to a minimum. End drives may be used on short conveyors. Continuous Chain Construction (Figures 8 trough 15) In this type construction, a single plate sprocket is attached to each roller, and a continuous strand or loop of chain drives all rollers by engaging just the top teeth of each driven sprocket. This construction can be used for moderate weight unit loads. It allows closer centerlines on carrying rollers than roll-to-roll construction. The construction is not intended for frequent stopping (except for emergency stopping) and starting applications. Contact with the sprocket teeth is maintained by a continuous cover plate with wearing bar hold-down. Chain is usually returned in a return track. An adjustable chain take-up is required with this construction. The end-rollers in this type construction should be equipped with precision ball bearings. Drives are normally located at head end of conveyor, but an intermediate drive on the return strand of chain may be used.

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“Double-strand” construction is also available. It consists of two (2) single strands of chain, or a single strand of double width chain, used to drive single rack tooth sprockets attached to each roller, with rack tooth sprockets on alternate rollers offset. This construction is used to obtain closer centerlines on the carrying rollers (See Figure 11) Live Shaft Construction (Figure 5) Live shaft construction may be either roll-to-roll or continuous chain type, with the roller (or tube) attached to a rotating shaft mounted in outboard flange or pillow block bearings and having the sprockets keyed to the shaft. The rollers for this type construction may be machined from solid round bar stock turned down on each end for mounting in bearings and attaching the driving sprockets. Normally used as roll-to-roll construction for handling very heavy loads, this construction may also be used when chain and sprocket cover guard must be below the top of carrying rolls. Chain Driven Live Roller Curves (Figures 2, 3, 4, 6 & 7) Chain driven curves may be either roll-to-roll construction or continuous chain construction and may have driving sprockets attached to rollers on the inside or outside radius of curve. Standard side bow chain and thin tooth plate sprockets are used for this construction. Normal construction has straight faced rollers; however, to prevent loads from riding the outside guide rail, true tapered rollers may be used. A true tapered roller provides the proper speed differential between the inside and outside of the load as it travels around the curve. Differential roller construction may also be used to compensate somewhat for the speed differential or for wide conveyors. This construction consists of a lane of driven rollers on the outside of the curve and a lane of non-powered idler rollers on the inside of the curve. It is recommended that the driven lane be approximately 2/3 of the total effective width of the conveyor, thus allowing 2/3 of the load width (and weight) to be on the driven roller lane. It is recommended that chain driven live roller curves be horizontal or with a slight decline. Transfers (Figures 16 trough 30) There are many types and variations of transfers used with chain driven live roller conveyor to transfer loads onto or off the conveyor at intermediate positions:

a) Disappearing pitched gravity roller section, where several lanes of idler rollers are set at right angles to the carrying rollers and are raised and lowered manually or by a power device (See Figure 30)

b) The disappearing roller section may be horizontal, instead of pitched gravity, and equipped with a powered pusher to transfer loads at right angle to the direction of main conveyor (See Figure 26)

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c) Disappearing chain transfer has two or more strands of chains set parallel to the carrying rollers and between the carrying rollers. Chains are usually driven by a gearmotor and are normally raised and lowered by pneumatics, hydraulics, or motorized mechanisms. (See Figure 24)

d) Light loads may be pushed off the chain driven live roller conveyor at right angles to the

direction of travel by means of a powered push-off device without the disappearing roller transfer feature. A disappearing plate stop is normally used in this application to stop the travel of the load and position it while being transferred; or the main conveyor may be stopped during the “push transfer” cycle (See Figure 27)

e) Light loads may also be deflected off the chain driven live roller conveyor by means of a

fixed, manually operated, or power operated deflector consisting of a bar pivoted to swing out over the conveyor (see Figures 18 and 20)

f) A chain driven live roller spur is a section of conveyor set at approximately 30 degrees to

the direction of travel of the main conveyor, with odd length rollers as required to mate with the side of the main conveyor. It is used to transfer loads onto a conveyor; or it may also be used to transfer loads off a powered conveyor with the use of a deflector (See Figures 18 and 19)

g) Other types of transfers are depicted on “Transfer Selection Data”.

Accumulating Chain Driven Live Roller For application data regarding common uses of chain driven live roller as accumulating conveyor, refer to previous articles discussing “cascade” and “indexing” accumulation (see “General Application Engineering Data”) Other low (or zero) storage line pressure accumulating chain driven live roller conveyor construction is available. However, most such construction is proprietary or patented.

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ROLL – TO – ROLL CHAIN DRIVEN LIVE ROLLER CONVEYOR

Figure 1. Side Views Typical Chain Driven Live Roller

Figure 2. Plan View 90 Degree Curve

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Figure 3. Roller to Roller Construction

Figure 4. Typical Straight and Curve

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Figure 5. Live Shaft

Figure 6. Straight-Faced Roller Curve

Figure 7. Tapered Roller Curve

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CONTINUOUS CHAIN DRIVEN LIVE ROLLER CONVEYOR

Figure 8.

Figure 9. Chain Driven Live Roll Curve Single-Strand, Continuous Chain Type

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Figure 10. Plan and Side Views of Single Side Chain

Figure 11. Plan and Side Views of Two-Sided Chain

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Figure 12. Typical Straight and Curve

Figure 13. Chain Drive on Outside Radius of Curve

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Figure 14. Chain Drive on Inside Radius of Curve

Figure 15. Tapered Roller Curve with Chain Drive on Outside Radius

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TRANSFER SELECTION DATA

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SECTION 3 – TECHNICAL DATA Symbols

a Number of non-powered rollers per driven roller Ci Number of non-powered rollers per foot of conveyor Cd Number of driven rollers per foot of conveyor Dr Diameter of rollers (in) Ds Pitch diameter of sprockets on driven rollers (in) F Friction factor (See Table 1) hp Horsepower i Roller chain loss factor L Conveyor length, [ft (m)] n Number of driven rollers in roller-to-roller chain driven live roller conveyor Pc Chain pull for continuous chain drive (lbs) Pn Chain pull for roller-to-roller drive (lbs) Q ( )1 1ni

i+ −

(See Table 2)

Rd Unit weight of driven roller and sprocket, less shaft (lbs) Ri Unit weight of non-powered roller less shaft, [lbs (kg)] v Conveyor speed, [fpm (m/min)] W ( ) ( )( )1d i r eR a R a W W+ × + + × + =Weight driven by each powered roller (lbs) Wc Weight of chain (lbs/ft) Wm Weight of conveyed material (lbs/ft) Wr Weight of conveyed material, pounds per roller We Weight of chain in one roller-to-roller loop

Metric Conversion Calculations must be performed in the English System, and the results must then be converted to metric.

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CHAIN PULL AND HORSEPOWER CALCULATIONS Equation #1: Effective Belt Pull The drive chain pull for a continuous chain driven live roller conveyor is given by the following equation:

( ) ( ) ( )( )0.25rc m c d d i i c

s

DP F L W W R C R C L WD

= × × + + × + × + × × (1)

Equation #2: Roll-to-Roll Construction The drive chain pull for a roll-to-roll chain driven live roller conveyor with “n” driven rolls is given by the following equation:

rn

s

DP F W QD

= × × × (2)

For both Equation (1) and Equation (2) above:

F = Friction Factor (from Table 1) W = ( ) ( )( )1d i r eR a R a W W+ × + + × + Q = ( )1 1ni

i+ −

(see table 2)

i = Roller Chain Loss Factor * r

s

DD

= Ratio of roller diameter to sprocket pitch diameter

* Roller chain loss will usually range between one percent (1%) and three percent (3%), depending on conditions of service. Under ideal conditions with well-lubricated chain, one percent (1%) can be used. Use 3% if operating conditions are severe and chain cannot be properly lubricated or maintained. In analyzing the developed relationship for chain pull in Equation 2, it is seen that chain pull develops exponentially with the number of progressively driven rollers. For this reason, the working strength of the chain will limit the number of loops. A practical maximum is approximately 150 loops or driven rollers in either direction from the drive sprocket. It is important that the value “n” be only the number of driven rollers. When idler rollers exist between the driven rollers, their weight and the load they support should be included as part of the total load driven by each powered roller. That is, the term “W” in the equation should represent the total weight of the driven roller, the live load on the driven roller, plus the weight of the idler roller and live load weight supported on each idler roller. In deriving the chain pull per Equation 1 or Equation 2 above, the following assumptions have been made:

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1) The total live load is uniformly distributed on all the rollers.

2) The load imposed on each bearing by the driving chains is negligible except for the roller or rollers coupled to the drive.

3) The pull required to turn each roller results from a combined rolling resistance between

roller and bearing and roller and load.

4) The chain transmission efficiency factor is constant.

5) The conveyor is horizontal and level. Note: Different companies use different factors. These calculations serve as a starting point for your company's design team. Equation #3 and 4: Horsepower Calculations After determining chain pull from previous calculations (Equation 1 or 2), to determine horsepower at head shaft, apply one of the following equations:

hp 33,000

c s

r

P v DD

× ×=

×… for Continuous Chain Construction (3)

hp 33,000

n s

r

P v DD

× ×=

×… for Roll-to-Roll Construction (4)

Increase horsepower requirements calculated above to compensate for friction loss in reducer or gearmotor. Consult manufacturer’s literature for friction loss factor or percentage.

Table 1. Friction Factor “F’”

Smooth Metal Wooden Pallet Cardboard0-25 0.040 0.045 0.050

26-100 0.030 0.035 0.050101-200 0.025 0.030 0.045

201 and higher 0.020 0.025 0.040

Surface Unit Load Contacting RollerTotal Weight on Each Roller (Includes Weight of Rollers)

(in)

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Table 2. Factor for Determining Value of “Q”

The value for “Q” is obtained by multiplying the actual number of driven rollers “n” by the factor obtained from the chart using the next larger multiple of driven rollers and the appropriate factor for “i”. Example: For “n” = 83 and “i” = .01, then “Q” = (1.61) 83 = 133.63 The value obtained is correct for a drive located at one end of the conveyor (see Figure 1) To minimize chain pull and drive HP requirements, the drive can be located in the center of the conveyor (see Figure 1). “Q” with a center drive is obtained by multiplying the actual number of driven rollers “n” by the factor obtained from the chart for 1/2 the quantity of driven rollers.

0.010 0.015 0.020 0.025 0.03010 1.05 1.07 1.09 1.12 1.1520 1.10 1.16 1.21 1.28 1.3430 1.16 1.25 1.35 1.46 1.5940 1.22 1.36 1.51 1.69 1.8950 1.29 1.47 1.69 1.95 2.2660 1.36 1.60 1.90 2.27 2.7270 1.44 1.75 2.14 2.65 3.2980 1.52 1.91 2.42 3.10 4.0290 1.61 2.09 2.75 3.66 4.93

100 1.70 2.29 3.12 4.33 6.07110 1.81 2.51 3.56 5.14 7.52120 1.92 2.76 4.07 6.12 9.36130 2.04 3.04 4.66 7.32 11.70140 2.16 3.35 5.36 8.78 14.68150 2.30 3.70 6.17 10.65 18.50

Roller Chaing Loss Factor "I"Driven Rollers

"n"

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Table 3. Minimum Sprocket Teeth per Roller Diameter

Minimum Roller Centers For roll-to-roll chain driven live roller conveyors, the minimum centers must be a multiple of 1/2 of chain pitch and must provide clearance between chains wrapped around sprockets on adjacent roller (see Figure 3, and Table 4, below). Roller centers can be reduced by driving every other roller (see Figure 4). The pinch point between the powered roller and idler roller must be guarded. Alternate routes may be driven from each side of the conveyor to obtain close spaced powered rollers. For continuous chain driven live roller conveyors, the minimum centers need only provide clearance between teeth of sprockets on adjacent rollers (see Figure 12). The centers can be reduced by driving every other roller (not recommended); or staggered sprockets driven by a single strand of double width chain or two (2) single strands of chain can be used to drive every other roller at the closest possible centers (see Figure 13)

Table 4. Minimum Roller Centers [in (mm)]

Refer to ANSI/CEMA Standard No. 401 for Conveyor Frame Calculations and Roller Bearing Capacity

1 3/4 (44.45) 1.9 (48.26) 2 (50.80) 2 1/4 (57.15) 2 1/2 (63.50) 2 9/16 (65.09) 3 1/2 (88.90)# 40 1/2 16 17 19 21 21 21 28# 50 5/8 15 15 15 17 17 17 23# 60 3/4 13 13 13 15 15 15 19# 80 1 13 13 16# 100 1 1/4 13

Roller Diameter [in (mm)]Pitch(in)

A.S.A. Chain Size

13 15 16 17 19 21 23 283 1/4 3 1/2 3 3/4 4 5 1/4

(82.55) (88.90) (95.25) (101.60) (133.35)3 11/16 4 1/16 5 1/16(93.66) (103.19) (134.94)

4 1/8 4 1/2 5 5/8 6 3/8104.77 114.30 142.87 161.925 1/2 6 1/2

139.70 165.106 7/8

174.62

A.S.A. Chain Size

Number of Sprocket Teeth

# 40

# 50

# 60

# 100

# 80

Documents

CEMA Standard No. 404 · 2019-06-11 · outboard bearings. In a chain driven live roller conveyor, rollers are powered via sprockets attached to either or both ends of the roller