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22 Material Delivery (power entry value)
Entered in the conveyor capacity routine in tons per hour.
May be for design delivery or other condition such as maximum load.
In running feeder calculations this value can be calculated for feeders with known bed depth and feeder speed.
Material delivery takes part in the power calculation for:
170 Weight of material on belt
178 Force to accelerate material
202 Power to accelerate material

23 Material Bulk Density (power entry value)
Entered in the conveyor capacity routine In mass units per cubic length units. Is the known material density on the conveyor.
It can be measured in the field but may vary under field conditions.
Material density should be considered as an approximation.

24 Belt Speed (power entry value)
Entered or calculated in the conveyor capacity routine.
Choose your speed for conveyors. For feeders speed can be calculated if bed depth and material delivery are known.

25 Belt Width (power entry value)
Entered in the conveyor capacity routine in millimeters or inches.
Standard widths are not required. Any width belt can be entered.

26 Carrier Roll Angle (capacity and power entry value)
Angle of side rollers on the carry side of the conveyor.

27 Surcharge Angle (capacity entry value)
Required to calculate conveyor capacity. more

Material density and surcharge angle are assumptions when the material varies because of changing composition or changing weather. Engineer and client should always agree on these two items before design work begins.

28 Width Between Skirtboards (power and feeder entry value)
Entered in the conveyor capacity routine.

29 Feeder Coefficient (Feeder Value)
By default is set to 1. If discharge opening is poor set to less than 1.

30 Feeder Feed - Height Above Belt (Feeder Value)
Either set or calculated in feeder capacity program.

32 Feeder Feed Rate (Feeder Value)
Can be calculated If speed, bed cut-off height, and opening width are known. Else is an entered value.

37 Material Depth at Skirtboard (calculated value)
Calculated by the conveyor capacity routine. The calculation is a precise geometric calculation based on the surcharge angle, width between skirtboards, material delivery, material density and belt cross-section geometry.
Since the surcharge angle and material density are usually an estimate, this value cannot be regarded as having the precision shown. Still, it usefully gives to the designer a standard picture.
This calculation is used calculate:
177 Skirtboard Drag which in turn is included in 185 Carry Side Drag.

128 Driving Conditions: Wet 0, Dry 1 (Entry value)
Possible drive pulley surface condition at any running situation. Outdoor conveyors are usually considered wet.
Affects 164 wrap factor, and thus all tensions.

129 Drive Pulley Lagging (rubber): grooved 0, smooth 1, none 2 (power entry value)
For other lagging materials calculate the wrap factor and choose the nearest corresponding for selection here.
Affects 164 wrap factors.

130 Set Roller Seal Friction (power entry value)
Default = 0
If you have information about the internal friction of the idlers (rollers) you are using you can enter it here.
If 130 is set to 0, the roller (idler) internal force value is calculated by the program to a standard, using the internal friction of roller bearings, the input of roll diameter and the input of conveyor width. This is generally adequate for the purpose.
If not set to 0 then 169 Idler (roller) internal drag includes this value.
Internal idler (roller) friction is not used (discounted as a braking force) in regenerative calculations.

131 Drive at Head 1, Mid 2, Tail 3 (power entry value)
Head is always the discharge end. Tail is always the feed end.
For dual drives: if no drive is at the terminal pulleys (head or tail) then enter 2.
If one drive is at the head terminal pulley, indicate 1.
If one drive is at the tail pulley enter 3.
If both head and tail have a drive, indicate the primary drive position (highest tension).

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132 Preferred Counter-weight or belt tension device (power entry value)
Default = 0. A value in mass units that overrides the program calculated 159 minimum counter-weight requirement. If this entered value is less than the calculated minimum, it will be ignored.
Conveyors are seldom fitted with a minimum counter-weight.
If you set this value to 0, the calculated minimum counter-weight will be adequate for estimating purposes. Else enter the actual counter-weight here at 132.

For initial screw take-up additional tension will be required to allow for stretch of the belt.
When checking a design by others enter the value of the counter-weight indicated for their design. This will give you comparable tension values.

133 Regenerative: No = 0, Yes = 1 (power entry value)
Note: Setting this to yes does not make a conveyor regenerative.
If set to 1, calculation is as regenerative (negative power).
If there is a down slope calculate both ways. Use the absolute higher power result.

134 Length, Horizontal (power entry value)
For estimating, this can be conveyor length as measured on a map. If doing a preliminary series of conveyors, use the intersection to intersection length.
The program calculates the length along the conveyor.

135 Lift, Vertical (power entry value)
For non-regenerative conveyors enter the difference in elevation from feed point to the highest point along the conveyor.
For regenerative conveyors enter a negative number representing the difference in elevation between the discharge elevation and the feed point elevation. Elevations are at the belt line. If the conveyor goes over a hill then check the design using the lift to the top of the hill

136 Carry Idler (Roller) Spacing (power entry value)
Always enter the carry side idler spacing at the low tension load carrying location.
Used for:
190 Catenary depth limit tension calculation.
163 Idler total drag factor
179 Carry side idler (roller) friction
184 Carry side drag, empty
185 Carry side drag, loaded

137 Return Idler Spacing (power entry value)
Enter average or normal return idler (roller) spacing
Used only for calculating the estimated number of return idlers

138 Idler Roll Diameter (power entry value)
Enter the general size of the carrying idlers (rollers).
Used to calculate Idler (roller) internal friction.
Roll size of return idlers (rollers) or specialty idlers have no significance.

139 Weight of Belt (power entry value)
Belt weight per unit length. From manufacturers data or field sample.

140 Material Feeding Speed (power entry value)
Default = 0. Speed of material in the direction of the belt as it is fed onto the belt.
Used in calculating the force required to 178 Accelerate the material. which is included in the summation 185 Carry side drag, loaded.

141 Drive Pulley Wrap (power entry value)
Enter the total wrap of all drives in degrees. If unknown use 180 degrees for a non-snubbed single drive, 210 degrees for a snubbed single drive and 380 degrees for dual drives.
Used for calculating 164 Wrap factor

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142 Catenary Depth Between Carry Rollers (power entry value)
The maximum catenary depth, in percent of idler (roller) spacing. Occurs at loaded belt lowest tension location, usually near the tail pulley. Usual range is 1 to 3 percent. Setting a lower catenary depth will contribute to overall higher tensions.

143 Set Conveyor Factor or enter 0 (power entry value)
Default = 0. This factor is called Ky, a CEMA convention, and is used for calculating the force of belt and load flexure over the idlers (rollers).
The program also calculates this factor as 161.
If you enter a value greater than zero here, that value will over-ride the calculated factor(161). This is useful for checking the work of others using their Ky value.
The actual factor used is reported at 160.

144 Low Ambient Temperature (power entry value)
Caution, this entry could have a significant effect on the calculations.
The minimum annual daily low temperature can usually be obtained for any location. Using that value for mild climates (minimum lows of -15C, 5F) is too low. Average the low with the same day’s high to get the entry value. The mean hourly temperature for the annual low temperature day, if available, would be more accurate for a continuously running conveyor and higher than the average temperature for that day.

Severely cold local temperatures require special consideration by the designer. Consider the following:
Continuous running 24/7
Scheduled shutdowns
Lower speed jury drives

Used for calculating the 162 Temperature factor.

145 Drive Efficiency (power entry value)
This is the efficiency of the device or speed reducer connected between the motor output shaft and the drive pulley shaft. Get from manufacturers literature, if possible. For preliminary work use 0.95 (conveyor) or 0.80 (feeder). Or use a value from your previous work.
Used at:
205 Power drive loss, empty
206 Power drive loss, loaded

146 Acceleration Factor (power entry value)
Usually set at 1.25. An allowance for applying the extra tension required for start-up conditions to a calculated minimum counter-weight.
If you enter a counter-weight value that exceeds the minimum calculated, this factor is ignored.

147 Belt Cleaners (scrapers) Unit Friction (power entry value)
Enter a value in lb-f/ft or kg-f/meter. You may have to convert the manufacturers rating. If you have more than one rating, average them.
Used to calculate 176 Belt cleaner drag.

148 Drive Pulley Friction, each (power entry value)
This item is a composite of pulley rotation resistance and belt and shaft bending energy all stated as a frictional resistance. There is no way to obtain accurate values for this. If you have no handbook data, make an estimate.

149 High Tension Pulley Friction, each (power entry value)
This item is a composite of pulley rotation resistance and belt and shaft bending energy all stated as a frictional resistance. There is no way to obtain accurate values for this. If you have no handbook data, make an estimate.

150 High Tension Pulley Count (power entry value)
Includes all high tension pulleys that are not drive pulleys.
Count those between the primary and secondary drive and those between the primary drive and the belt carry side.

151 Low Tension Pulley Friction, each (power entry value)
This item is a composite of pulley rotation resistance and belt and shaft bending energy all stated as a frictional resistance. There is no way to obtain accurate values for this. If you have no handbook data, make an estimate.

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152 Low Tension Pulleys Count (power entry value)
On up-hill conveyors low tension pulleys are those between the secondary drive and the tail pulley and include the tail pulley.
On down-hill conveyors low tension pulleys are those between the secondary drive and the discharge pulley and include the discharge pulley.

153 Friction of Conveyor Plows (power entry value)
Total plow drag. Plow refers to a device removing delivered material from the carry side of the conveyor.
If there are more than one operating simultaneously, add them together. Sometimes obtained by taking belt width x 5 lb-f, 2.25 kg-f. Cut in half if plow does not clear all material from conveyor.

154 Trippers or Accessories Drag (power entry value)
Total drag of carry side devices other than plows.
Can also be used for adjustments. Will accept negative numbers.

155 Belt Cleaner Count (power entry value)
Include all carry side and return side belt cleaning devices.

156 Skirtboard Length (power entry value)
Refers to the length of the skirtboard assembly where it touches the belt.
The term ‘fully skirted’, means the skirtboard length equals the length along the conveyor. The length along the conveyor value is calculated in the ‘Power’ page, therefore, you can calculate to obtain this length, correct the skirtboard length accordingly and then recalculate.

157 Take-up at Drive = 1, Not = 0 (power entry value)
Indicate if take-up is at drive or not. Affects required counter-weight.

158 Material Repose Angle (power entry value)
The angle between level ground and the sloping side of dumped material.
Will default to 37 (if you enter zero). This value was set to 37 in mConveyor versions previous to 3.
This angle is used to calculate 165 Skirtboard drag factor.

159 Take-up, Minimum Counter-weight
This is the calculated minimum suspended mass that will satisfy both the 197 drive slack tension required for driving and the tension needed to provide the 196 minimum catenary tension.
This tension is stated as a counter-weight of twice the required take-up belt tension and indicates the force required on the take-up pulley under running conditions whether it is a hanging counter-weight or a force applied by some other means.

This value will include tension to handle starting acceleration, if applied at 146.
Location of T-U must be supplied. Click << to 157.
A counter-weight greater than this computed requirement can be entered at 132 Preferred counter weight.

160 Conveyor Factor
The friction factor actually used in the calculation, which can be specified (143) or internally derived at161 next >>.

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161 Derived Conveyor Factor
This is the friction factor that accounts for belt and load passing over the idlers (rollers). It is dependent on idler (roller) spacing and belt tension on the carry side.
This is the same as Ky, a CEMA designation, a factor calculated from belt width, belt load, material load, idler (roller) spacing and belt slope per CEMA specifications.
It was derived from field work with actual conveyors and is one of the usable standards. Values for high tensions beyond the original tables have been extrapolated.

162 Temperature Friction Factor
Calculated temperature factor for 144 low ambient temperature.
Affects calculations:
179 Carry side idler (roller) drag
180 Carry side belt flexure drag
181 Return side belt and idler (roller) drag

163 Idler (Roller) Total Friction Factor
Per unit belt length frictional force including idler rolling friction and idler sliding contact with the belt.
For regenerative conveyors idler friction (as a braking force) is reduced by not including rolling friction.
For the return side, this factor is 0.015 lb-f, 0.007 kg-f.
This factor is applied to calculate 179 Carry side mechanical drag.

164 Wrap Factor
Is dependant on 128 wet or dry conditions, whether the drive pulley is 129 lagged or not and if the lagging is grooved or smooth.

165 Skirtboard Friction Factor
Calculated skirtboard friction factor is dependent on material density and the depth at skirtboard, calculated in the capacity worksheet, and 158 repose angle.
Why not use surcharge angle?
Surcharge angle is an estimate, whereas, repose angle can be obtained from tables or field measurement.

166 Return Belt Weight at Take-up
If there is distance between the take-up and the low tension terminal pulley and the take-up is at a higher elevation, the return belt weight at take-up is the unit belt weight multiplied by the elevation difference.
Required to calculate minimum 196 slack side tension and 193 tension at tail pulley.

167 Drive Count
Calculated from 141 entered wrap.

168 Roller (Idler) Rotation Speed
Calculated RPM of roller is provided. It is not used in the conveyor calculations.

169 Roller (Idler) Internal Drag, each
A calculated value for the sum of internal idler (roller) frictions, bearings and seals, under load conditions.
Used in the calculation of 163 Idler (roller) total friction factor
for non-regenerative conveyors.

170 Belt Load
Weight of material on belt per unit length of belt.

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171 Approximate Carry Roller (Idler) Count
Estimate of idlers (rollers) required with about 5% overage.

172 Approximate Return Roller (Idler) Count
Estimate of idlers (rollers) required with about 5% overage.

173 Approximate Length along Belt
Calculation of straight length using known horizontal length and lift.
In previous versions was approximate length of belting. In your estimating program you must now allow for the return side, vertical curves, pulley wrap, take-up, stretch and splices.

174 Total Pulley Friction, Low-tension Non-driving
Total pulley friction for slack side pulleys including take-ups and low tension terminal pulley.
Product of:
152 Low tension pulleys count
151 Low tension pulley friction.

175 Total Pulley Friction, Hi-ten Non-drive
Total pulley friction for high tension pulleys. For mid-drive conveyors the discharge pulley is included and any pulley on the return side before or between the drive pulleys.

176 Belt Cleaner Drag
Total drag caused by belt cleaners. Include return side plows.
Product of:
147 Scraper force per unit belt width
123 Belt width
155 Scraper count.

177 Skirtboard Drag
Drag caused by all skirtboards.
A product of:
165 skirtboard friction factor
122 Depth of material at the skirtboards (provided by the capacity worksheet)
156 skirtboard length.

178 Force to Accelerate Material
Force to bring material up to belt speed.
Calculated as dependent on 140 material feeding speed.

179 Carry Side Idler (Roller) Drag
Product of the conveyor length along the belt, 163 idler friction factor and 162 temperature factor.
Input to:
184 Carry side drag, empty
185 Carry side drag, loaded
200 Power for friction

180 Carry Side Belt Flexure Drag
Product of:
The conveyor length along the belt and
160 conveyor factor (Ky)
139 belt weight per unit length
162 temperature factor

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181 Return Side Belt and Idler (Roller) Drag
Combined idler and belt flexure friction on the return side.
Product of:
The conveyor length along the belt
Return side conveyor factor (a fixed value)
139 belt weight per unit length
162 temperature factor.

182 Carry Side Material Flexure Drag
Friction attributable to material flexure only.
Product of:
The conveyor length along the belt
160 conveyor factor (Ky)
170 material weight per unit length

183 Lift Tension, Material
Tension attributable to lifting the material.
Product of:
135 conveyor lift
170 material weight per unit length

184 Carry Side Drag, Empty
All carry side drag running empty.
Sum of:
179 carry side idler friction
180 carry side belt flexure drag
154 tripper and accessories drag

185 Carry Side Drag When Loaded
All carry side friction running with the input load.
Is included in:
189 Effective tension, loaded
194 Discharge pulley tension at top
Includes:
176 Belt cleaner drag
179 Carry side idler drag
180 Carry side belt flexure drag
182 Carry side material flexure drag
178 Force to accelerate material
177 Skirtboard drag
153 Plow drag
154 Trippers or accessories drag

186 Return Side Drag, Low Tension Zone.
All return side friction on low tension side of the drive.
Is included in:
196 Minimum slack tension for the catenary depth
193 Tail pulley tension at top
Includes:
181 Return side belt flexure and idler drag
174 Low tension non-driving pulley drag

187 Return Side Drag (high tension)
All return side friction on high tension side of the secondary drive.
Is the sum of:
174 high tension non-driving pulley drag
and 2/3 of 176 belt cleaner losses.

188 Effective Tension, Empty
Tension difference across complete drive under empty running conditions created by the motor
power input.
Sum of:
184 Carry side drag, empty
186 Return side drag (low tension)
187 Return side drag (high tension

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189 Effective Tension, Loaded
Tension difference across complete drive under loaded running conditions created by the motor power input.
Sum of:
183 Lift tension, material
185 Carry side drag when loaded
186 Return side drag (low tension)
187 Return side drag (high tension)

190 Catenary Depth Limit Tension
This is the minimum tension allowed anywhere on the load carrying side.
Derived from:
142 percent catenary depth
136 carry idler spacing
139 belt weight per unit length
170 material weight on belt per unit belt length.

191 Drive High Tension
Actual belt tension at high tension side of drive.
Sum of:
189 Effective tension, loaded
192 Drive slack tension

192 Drive Slack Tension
The actual drive slack side tension is derived from:
The 197 tension required for driving
or that required for 196 maintaining minimum catenary depth, whichever is greater.
Plus 132 counterweight above minimum, if any.

193 Tail Pulley Tension at Top
The tail pulley is always near the feed point.
On regenerative conveyors it may be the highest top side tension.
On non-regenerative conveyors it may be the lowest top side tension.
It will vary with the drive location, 3 cases.
It is calculated by summing the proper values out of 6 cases

194 Discharge Pulley Tension at Top
On non-regenerative conveyors it may be the highest top side tension.
On regenerative conveyors it may be the lowest top side tension.
It will vary with the drive location, 3 cases.
It is calculated by summing the proper values out of 6 cases

195 Average Carry Side Tension
Reported for information only.

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196 Minimum Slack Tension for Set Catenary Depth
The minimum slack side tension at the drive pulley, (the secondary drive, if one exists), to achieve 190 Catenary depth limit tension.

197 Minimum Slack Tension for Driving
The minimum slack side tension at the drive pulley (the secondary drive, if one exists), to achieve 189 Effective tension. using the drive set wrap factor.

198 Power Required at Motor (empty)
The motor power required for running empty is calculated using:
188 Effective tension for running empty

199 Power at Motor (design load)
The motor power required for running loaded is calculated using:
189 Effective tension, loaded

200 Power to Overcome Drag
The motor power required for all conveyor frictional drag.

201 Power to Lift Material
The motor power required to lift the material.

202 Power to Accelerate Material
The motor power required to accelerate the material.

203 Power Loss of Belt Cleaners
The motor power required to overcome the friction of the belt cleaners.

204 Power Loss of Skirtboards
The motor power required to overcome the friction of the skirtboards.

205 Power Drive Loss, Empty
The motor power required to overcome the friction loss of the speed reducers while running empty.

206 Power Drive Loss, Loaded
The motor power required to overcome the friction loss of the speed reducers while running loaded.
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