Module 11: Harvesting Equipment Flashcards
process of gathering the useful portion of the crop from the field
harvesting
process of separating the grains from the straw
threshing
process of detaching and separating the kernels from the cobs (corn) or pods (legumes)
shelling
traditional
harvesting: 8 - ____ man-hours/ha
threshing: __ - 220 man-hours/ha
8 - 160
140 -220
losses in traditional harvesting and threshing
5% to 16%
conventional threshing
power thresher: ____ man-hours/ha
pedal thresher: _____ man-hours/ha
12 for power; 100 for pedal
losses in conventional threshing
3% to 10 %
this is the most common scheme in harvesting and threshing of rice
conventional threshing
mechanical threshing
manually operated harvesting takes about 5 man-hours/ha
true or false
false; it takes 50 man-hours/ha
mechanical harvesting
manually operated harvesting takes about 50 man-hours/ha
true or false
true
losses in mechanical threshing
3% to 6%
use of a machine called “combine”
combine harvestingr
harvesting, threshing, and cleaning in one operation
combine harvesting
this system is commonly adopted in countries with vast areas planted with cereal grains
combine harvesting
labor in combine harvesting
3-21 man-hours/ha
losses in combine harvesting
1.5% to 6%
use of a machine called “stripper”
stripping
this system removes or “strips” the grains from the panicle without cutting or uprooting the plant
stripping
labor in stripping
3-21 man-hours/ha
losses in stripping
2% to 6%
factors affecting the choice of harvesting and threshing systems
- type of crop
- topography
- farm size
- type of culture
- availability and cost of labor
- availability of capital
- timeliness of operation
factors affecting the choice of harvesting and threshing systems
crops have diff properties
type of crop
________ is employed for crops in which grains or pods do not mature at the same time
priming
some crop varieties are susceptible to ______ during the rainy season
lodging
mechanical harvesting, combining and stripping are ideal for?
flat fields, free of large obstructions
manual harvesting and threshing are widely adopted in areas with steep slopes
true or false
true
area of an average ph farm
2 ha
use of mechanical methods in small and non-contiguous farms is efficient
true or false
false; it is not efficient
there is an unreliable supply of hired labor in farming
true or false
true
that’s why farmers consider the use of mechanical methods
level of mechanization in harvesting
low level
done using non-mechanical sources (sickle, and reapers in some areas like region 3)
level of mechanization
more than 92% of the harvesting operations in which regions are done manually
region 1, 2 and 3
level of mechanization in threshing
intermediate
done by both mechanical and non-mechanical power sources
level of mechanization
more than 80% of farms are threshed with _____________ which come in diff sizes and forms
axial-flow threshers
2 main harvesting equipment
- hand tools
- reapers
2 main harvesting equipment
relatively small and handy
hand tools
2 main harvesting equipment
easy to use since they do not require mechanical manipulations during their operation
hand tools
2 main harvesting equipment
machines the cut the standing grain crop
reapers
classification of reapers
- reaper-windrowers
- reaper-binders
examples of hand tools
- yatab
- lingkao
- scythe
cutting mechanisms for harvesters
- slicing and tearing actions
- high velocity, single-element, impact action
- double-element, scissor-type action
cutting mechanisms for harvesters
results in plant material failure dure to compression, tension or shear
slicing and tearing actions
slicing action: ______________ blades
______________: rough, serrated-edged blades
slicing action: sharp, smooth-edged blades
tearing action: rough, serrated-edged blades
cutting mechanisms for harvesters
a high-speed rotary saw is used to cut plant materials
high velocity, single element, impact action
cutting mechanisms for harvesters
employs shearing action between moving and stationary blades to cut agricultural crops
double-element, scissor-type action
cutting mechanisms for harvesters
most common cutting mechanism used for reapers and combines
double-element, scissor-type action
threshing occurs when the applied force on the grains exceeds the sum of the force restraining them
true or false
true
threshing methods
- rubbing
- impact
- stripping
threshing methods
grains are pressed against the straws and the threshing flow or mat
rubbing action
threshing methods
employed in man and animal treading
rubbing action
threshing methods
grains are accelerated faster then their panicles
impact action
threshing methods
in rubbing action, the friction should exceed the force holding the grains
true or false
true
threshing methods
employed in mechanical threshers and the hampasan
impact action
threshing methods
grains are detached from their panicles when the straw is pulled through a “V” configuration or a comb-like device or vice versa
stripping action
threshing equipment
employs impact action to detach the grains from the panicles
mechanical threshers
types of mechanical threshers according to the power source
- manual thresher (pedal)
- power thresher
types of mechanical threshers according to the type of feeding
the panicles of the cut crop is fed into the threshing chamber while the stalks are mechanically or manually held during the operation
hold-on feeding
types of mechanical threshers according to the type of feeding
the grains, together with the straw, are fed into the threshing unit of the machine
throw-in feeding
types of mechanical threshers according to the type of feeding
requires lower power during the operation
hold-on feeding
types of mechanical threshers according to the type of feeding
requires high power during the operation
throw-in feeding
types of mechanical threshers according to the type of feeding
throw-in feeding has lightweight construction
true or false
false; it has heavyweight construction
types of mechanical threshers according to the type of feeding
employed in pedal thresher
hold-on feeding
types of mechanical threshers according to the type of feeding
employed in axial flow thresher
throw-in feeding
types of mechanical threshers according to the flow of threshing materials
- tangential flow
- axial flow
types of mechanical threshers according to the flow of threshing materials
materials are fed between the rotating cylinder and stationary concave and go straight out of the thresher chamber tangentially
tangential flow
types of mechanical threshers according to the flow of threshing materials
allow the cut crop to move in a helical manner around the threshing cylinder with a net effect of moving the threshing materials axially between the feeding and discharge outlet
axial flow
types of mechanical threshers according to the flow of threshing materials
in axial flow, about 60% of the grains pass through the concave and the rest are separated in subsequent operations
true or false
false; that’s in tangential flow
axial flow is 90%
types of mechanical threshers according to type of threshing cylinder
- rasp-bar cylinder
- peg-toothed cylinder
- wire loop cylinder
types of mechanical threshers according to type of threshing cylinder
bar-like protrusions in parallel orientation are laid in the periphery of the cylinder * adopted for a wide variety of crops like peanut and other cereal crops because of its “mild” action
rasp-bar cylinder
types of mechanical threshers according to type of threshing cylinder
quipped with spikes or pegs on its periphery in tandem or helical arrangement * most common cylinder used by axial flow threshers for rice
peg-toothed cylinder
types of mechanical threshers according to type of threshing cylinder
wire loops of the same size and arc are attached on the periphery of the cylinder in tandem or staggered arrangement
wire-loop cylinder
mobile grain harvesting machines for cutting, picking, stripping or picking up crop, threshing, separating, cleaning, and conveying grain into a grain hopper and depositing harvest residue onto the ground.
rice combine
separation of bulky straw, chaff, empty kernels and very light and fine impurities from the grain employed in strippers
grain cleaning
accomplished by pneumatic means like the use of blowers or fans aided by oscillating screens and sieves
grain cleaning
in hold-on threshers, straws do not pass through the thresher and only the removal of the chaff and light materials are needed using blowers and screens
true or false
true
for throw-in threshers, straws pass through the thresher and ___________ is done using a straw walker, blower and screens.
cleaning
2 types of rice combine
- wheeled-type rice combine
- track-type rice combine
2 types of rice combine
equipped with pneumatic wheels or steel cage wheels
US and european combines
wheeled-type rice combine
rice combine
- fitted with full or half tracks instead of pneumatic tires
- relatively small and light machine
- particularly useful in fields with relatively soft soil
- suited in low-land conditions and small farms
track-type rice combine
local agmech techs
A mango harvester equip with a net at the end
of the pole. Able to reach mango fruits with
minimized or no damaged.
BPI Mango Picker
