1、Straw bale pressA baler is a piece of farm machinery used to compress a cut and raked crop (such as hay, straw, or silage) into compact bales that are easy to handle, transport and store. Several different types of balers are commonly used, each producing a different type of bales -rectangular or cy

2、lindrical, of various sizes, bound with twine, netting, or wire. Industrial balers are also used in material recycling facilities, primarily for baling metal, plastic, or paper for transport.Round balerThe most frequently used type of baler in industrialized countries is the large round baler. It pr

3、oduces cylinder-shaped "round" or "rolled" bales. Grass is rolled up inside the baler using rubberized belts, fixed rollers, or a combination of the two. When the bale reaches a predetermined size, either netting or twine is wrapped around it to hold its shape. The back of the ba

4、ler swings open, and the bale is discharged. The bales are complete at this stage, but they may also be wrapped in plastic sheeting by a bale wrapper, either to keep hay dry when stored outside or convert damp grass into silage. Variable-chamber balers typically produce bales from 48 to 72 inches (1

5、20 to 180 cm) in diameter and up to 60 inches (150 cm) in width. The bales can weigh anywhere from 1,100 to 2,200 pounds (500 to 1,000 kg), depending upon size, material, and moisture content.Originally conceived by Ummo Luebbens circa 1910, the first round baler did not see production until 1947, w

6、hen Allis-Chalmers introduced the Roto-Baler. Marketed for the water-shedding and light weight properties of its hay bales, AC had sold nearly 70,000 units by the end of production in 1960.The next major innovation came in 1972, when the Vermeer Company began selling its model 605 - the first modern

7、 round baler. Previously, round hay bales had been little more than lumps of grass tied together, but the Vermeer design used belts to compact hay into a cylindrical shape as is seen today.Large rectangular balerAnother type of baler in common use produces large rectangular bales, each bound with a

8、half dozen or so strings of twine which are then knotted. Such bales are highly compacted and generally weigh somewhat more than round bales. In the prairies of Canada they are called prairie raptors.Small rectangular balerA type of baler which is less common today in some places but which is still

9、prevalent in many countries such as New Zealand and Australia to the exclusion of large bales produces small rectangular (often called "square") bales. Each bale is about 15 in x 18 in x 40 in (40 x 45 x 100 cm). The bales are wrapped with two, three, or sometimes four strands of knotted t

10、wine. The bales are light enough for one person to handle, about 45 to 60 inches (1.1 to 1.5 m).To form the bale, the material to be baled, (which is often hay or straw) in the windrow is lifted by tines in the baler's pickup. This material is then dragged or augered into a chamber that runs the

11、 length of one side of the baler. A combination plunger and knife moves back and forth in the front end of this chamber. The knife, positioned just ahead of the plunger, cuts off the material at the spot where it enters the chamber from the pickup. The plunger rams the material rearwards, compressin

12、g it into the bales. A measuring device measures the amount of material that is being compressed and, at the appropriate length it triggers the mechanism (the knotter) that wraps the twine around the bale and ties it off. As the next bale is formed the tied one is driven out of the rear of the balin

13、g chamber onto the ground or onto a special wagon hooked to the rear of the baler. This process continues as long as there is material to be baled, and twine to tie it with.This form of bale is not much used in large-scale commercial agriculture, because of the costs involved in handling many small

14、bales. However, it enjoys some popularity in small-scale, low-mechanization agriculture and horse-keeping. Besides using simpler machinery and being easy to handle, these small bales can also be used for insulation and building materials in straw-bale construction. Square bales will also generally w

15、eather better than round bales because a more much dense stack can be put up.Convenience is also a major factor in farmers deciding to continue putting up square bales, as they make feeding and bedding in confined areas (stables, barns, etc.) much easier.Many of these older balers are still to be fo

16、und on farms today, particularly in dry areas, where bales can be left outside for long periods.The automatic-baler for small square bales took on most of its present form in 1940. It was first manufactured by the New Holland Ag and it used a small petrol engine to provide operating power. It is bas

17、ed on a 1937 invention for a twine-tie baler with automatic pick up.Wire balersBales prior to 1937 were manually wire-tied with two baling wires. Even earlier, the baler was a stationary implement, driven by power take-off (PTO) and belt, with the hay being brought to the baler and fed in by hand. T

18、he biggest change to this type of baler since 1940 is being powered by the tractor through its PTO, instead of by a built-in internal combustion engine.In present day production, small square balers can be ordered with twine knotters or wire tie knotters.Pickup and handling methodsIn the 1940s most

19、farmers would bale hay in the field with a small tractor with 20 or less horsepower, and the tied bales would be dropped onto the ground as the baler moved through the field. Another team of workers with horses and a flatbed wagon with would come by and use a sharp metal hook to grab the bale and th

20、row it up onto the wagon while an assistant stacks the bale, for transport to the barn.A later time-saving innovation was to tow the flatbed wagon directly behind the baler, and the bale would be pushed up a ramp to a waiting attendant on the wagon. The attendant hooks the bale off the ramp and stac

21、ks it on the wagon, while waiting for the next bale to be produced.Eventually, as tractor horsepower increased, the thrower-baler became possible, which eliminated the need for someone to stand on the wagon and pick up the finished bales. The first thrower mechanism used two fast-moving friction bel

22、ts to grab finished bales and throw them at an angle up in the air onto the bale wagon. The bale wagon was modified from a flatbed into a 3-sided skeleton frame open at the front, to act as a catcher's net for the thrown bales.As tractor horsepower further increased, the next innovation of the t

23、hrower-baler was the hydraulic tossing baler. This employs a flat pan behind the bale knotter. As bales advance out the back of the baler, they are pushed onto the pan one at a time. When the bale has moved fully onto the pan, the pan suddenly pops up, pushed by a large hydraulic cylinder, and tosse

24、s the bale up into the wagon like a catapult.The pan-thrower method puts much less stress on the bales compared to the belt-thrower. The friction belts of the belt-thrower stress the twine and knots as they grip the bale, and would occasionally cause bales to break apart in the thrower or when the b

25、ales landed in the wagon.New Holland has invented a machine named the "Stackcruiser", or a stacker. Small "square" bales are dropped by the baler with the strings facing outward, the stacker will drive up to the bales and it will pick it up and set it on a three-bale-wide table (

26、the strings are now facing upwards). Once three bales are on the table, the table lifts up and back, causing the three bales to face strings to the side again; this happens 3 more times until there are 16 bales on the main table. This table will lift like the smaller one, and the bales will be up ag

27、ainst a vertical table. The machine will hold 160 bales (ten tiers), usually there will be cross-tiers near the center to keep the stack from swaying or collapsing if any weight is applied to the top of the stack. The full load will be transported to a barn, the whole rear of the stacker will tilt upwards until it is vertical. There will be two pushers that will extend through the machine and hold the bottom of the stack from being pulled out from the stacker while it is driven out of the barn.In Britain (if small square bales are st