Multistation conveyor analysis cont

1
Multi-station conveyor analysis (cont)

• Assumption Conveyor is operated over an infinite
  period of time ? the sequences fi(n) are
  assumed to be periodic with period p
• fi(n) fi(np)

• We use the following relation

• Muths results
• k/p cannot be integers for steady-state
  operations
• r k mod p, r/p must be a proper fraction for
  general sequences F1(n) to be accommodated
• It is desirable for p to be a prime number, as
  conveyor compatibility results for all admissible
  values of k

2
Multi-station conveyor analysis (cont)

• The materials balance equation for carrier n
  H1(n) H1(n-r) F1(n)
• We need to find values of Hi(n)
• Method
• Let H1(n) be a particular solution to the above
  equation. Using recursion H1(n) H1(n-r)
  F1(n) by letting H1(1) 0.
• Given Hi(n), the value of Hi1(n) Hi(n)
  fi(n)
• Given Hi(n) for i 1,2,,s, let c min
  Hi(n)
• The desired solution is Hi(n) Hi(n) c
• The required capacity per carrier is B max
  Hi(n)

3
Conveyor Power Requirements

• Cost of trolley conveyor depends on
• length of conveyor
• number and size of carriers
• Installation cost
• Operation cost

• Horsepower requirement depends on
• conveyor speed
• weight of conveyor
• material being transported

4
HP calculations (Belt Conveyor)
Quick and dirty model

• Belt Conveyors Transporting packages, toteboxes,
  pallet

• S conveyor speed (fpm)
• L load to be carried by conveyor (lb)
• TL total length of conveyor (ft)
• RC roller spacing (in)
• WBR width between rails (in) (belt width)
• angle of incline (degrees)
• LLI live load on incline (lb) (weight of
  material on the conveyor section that is
  inclined)
• BV base value ( 2/3 WBR)
• FF friction factor ( 0.05 for roller
  supported 0.3 for slider bed supported)
• LF length factor (given in table 12.11)
• HP BV LF(TL) FF(L) LLI(sin ?)(S)/14,000

5
HP Calculations (Roller Conveyors)

• Similar to Belt Conveyor
• Different values of FF, BV, LF
• BV 4.60 0.445(WBR)
• FF 0.10 (for flat belt to drive the rollers)
  0.085 (for a zero pressure accumulating belt
  to drive the rollers 0.075 (for a v-belt
  to drive the rollers) 0.05 (chain driven
  rollers)
• LF is given in table 12.12