PROBLEM  STATEMENT  :-

1. Generally, the workers carry the cement bag on their back during loading and unloading .which is not a proper way to handled the cement bag. this causes health problems sometimes.
2. When workers handle the cement bags during loading and unloading they use the hooks for uplift the bag
3. Because of hook used during loading and unloading time there are 8 holes created on the cement bag and due to this near about 4 kg cement is wasted .

OBJECTIVE :-

1. The main objective of this project is to pick the cement bag from stacking position in warehouses and to keep it on moving conveyor belt .
2. so, the main task is to design and fabricate the mechanical system to pick the cement bag from stacking position in warehouses and to keep it on moving conveyor belt .

BRAINSTORMING IDEAS ABOUT CEMENT BAG HANDLING PROJECT
following ideas coming out during brainstorming session :
1. JCB arm
2. Mobile vaccume lifter
3. Crane system
4. rubber cover for pulling arm
5. change the stacking system
6. Circular stacking
7. lengthwise stacking
8. soft tooth jaw by pulling action
9. robotic palletizer

CEMENT BAG WAREHOUSE OBSERVATIONS :

I visited at ” samarth cement warehouse in pabal” ,at there I observed the following things:
1. I observe the overall cement warehouse.
there is a stack of 50 kg bag each.
2. warehouse is an air-tight room with no window.
3.Around 13 bags in one stacking system in 50 kg bag category.
4.Bombay stacking :- Alternate width wise and lengthwise arrangement of cement bags in warehouse .
5.Stack the cement bags off the floor on wooden planks in such way that ,it is about 150 - 200 mm above the floor.
6. Distance maintained between outer layer of cement bag stacks and interior wall is 600 mm.
7.height of stack should not be more than 15 - 20 bags to prevent possibility of lumping under pressure .
8. width of the stack should not be more than 4 bags length or 3 m
dimension of cement bag :- length = 70 cm , width = 35 cm , thickness = 14 cm
  • Actual cement bags warehouse image
Concept 1.
To lift the cement bag by clamping action using Tripod system :
Ideation of concept :
I select the tripod system with considering following parts :
# gripper
# tripod
# hoist motor
# hoist chain
# hook to connect hoist chain and gripper.
The gripper is connected to hoist motor with the help of hoist chain and hook , adjust the cement bag inside the gripper manually & when gripper move upward then its arms create a compressive force simultaneously, because of compressive force cement bag is hold tightly by gripper & it will lift the cement bag .

CAD assembly of tripod system

Gripper cad part

Tripod cad part

Problems created in tripod system
1) we did not have a sufficient space to settle down tripod gripper system in warehouses.
2) we did not pick the cement bag by using its opposite sides because the opposite side of cement bag is engage with other bag
3) if we used this tripod gripper system then stacking in warehouses must be in circular way which is practically not possible.
Concept 2.
To pull the cement bag by using V-shape fork
:
Ideation of concept :
after failure in tripod system I select the V-shape fork concept to pull the cement bag
# Why I select V- shape fork :-
1) I select V-shape fork because of considering pressure and force distribution parameter on cement bag .
# How concept works :
1) First I made the C - frame using L-angles then V -shape jaw is connected to C-frame with the help of metallic strips and hinges.
2) V-shape jaw is constrained near hinges with help of metallic strips to avoid its upward angular motion.
3) when the C -frame moves forward by AC 3 phase induction motor of 360 watt then V-shape jaw is adjust manually around cement bag & then during reverse motion of C-frame the cement bag get pulled.

motor used :- for forward and reverse motion
                            ac induction motor , 3 phase
                           motor capacity +360 watt
                            rpm+1440
                            current = 0.86 amp
Mini electric hoist :- for upward and downward motion
                                load capacity :-250/500 kg
                                voltage :- 220 v
                                 frequency :- 60 Hz , i/p power = 900 watt

CAD geometry of V-shape jaw :

Calculations:-

Bulk density of cement =mass/volume

Density of cement =1440 kg/m3

Mass of cement bag= 50kg

Volume of cement bag= 0.0347 m3

contact edge / length between two bags = 50mm

contact width /edge between two bags =30 mm

Contact area between two cement bags = l * w = 50*30=1500 cm2

# force required to pull the cement bag by practical approach , F = m*g

mass required to pull the cement bag from stack =19.7 kg

gravitational acceleration = 9.81 m/s2

so , force required to pull the cement bag by practical approach , F = 193.257 N

Conclusion :- 
1. The fabricated V- shape fork mechanism pull the cement bag successfully upto first 3 rollers