TEST REPORT No. 14a 003a

Transcription

1 AGRICULTURAL MACHINES FUNCTIONAL AND SAFETY TESTING SERVICE TEST REPORT No. 14a 003a ROTARY MOWER CONDITIONER: FC 243 RTG (extension: 14a-003b - FC 283 RTG) MANUFACTURER: KUHN S.A SAVERNE CEDEX (FRANCE) Marketed by: KUHN ITALIA S.r.l. Via Cerca per Colturano, Melegnano (MI) Rome, November 2002

2 TESTS CARRIED OUT IN COMPLIANCE WITH ENAMA SPECIFICATIONS NO. 14 BY EXPERIMENTAL INSTITUTE FOR AGRICULTURAL MECHANISATION, TREVIGLIO SECTION (BG): Supervisor Ing. Giovanni Santoro Dr Carlo Bisaglia P.a. Enrico Colombo TABLE OF CONTENTS DESCRIPTION OF MACHINE 3 TECHNICAL DATA 4 TEST CONDITIONS 4 RESULTS OF TESTS 5 CONCLUSIONS 7 REMARKS AND INSTRUCTIONS 7 TESTING OF SAFETY REQUIREMENTS 7 MODELS IN THE SAME SERIES 7 To facilitate interpretation of the results, it should be remembered that: 1 rpm = 1 min -1 1 MPa = 10 bar 1 kw = 1.36 CV 1 m 3 /s = 3600 m 3 /h 1 m/s = 3.6 km/h 1 l = 1 dm 3 DM = dry matter C.V. (coefficient of variation) = parameter indicating the extent of data deviation from mean value. 2

3 Figure 1 Front view of machine: 1) swivel hitch; 2) support stand; 3) disc cutter bar; 4) transmission to cardan shaft; 5) cutter bar ground plate; 6) cutting height adjuster; 7) spring-controlled suspension for mower; 8) rubber roller conditioner; 9) drawbar with hydraulic folding; 10) mower lift device. Description of machine The Kuhn rotary disc mower conditioner, mod. FC 243 RTG (Fig. 1), is a trailed implement for cutting meadow forage. The implement is fitted with a rubber roller device for conditioning the mown product. The tested model has a theoretical working width of 2.4 m; the RTG series consists of a range of two models whose working widths vary from 2.4 to 2.8 m. Forage cutting operations are based on the kinetic energy effect of the two cutting blades of each disc against the base of the stems, which are capable of considerable flexural rigidity. In construction terms the implement consists of a quadrangular upside-down U-shaped frame supporting the cutter bar, fitted with two wheels to support the implement during both field operations and transport. Attached to the frame is the drawbar which, by means of a dualeffect hydraulic jack, allows the bar to be cantilevered or at the rear of the tractor according to respective operating or transport needs. The cutter bar hangs from the frame by means of four adjustable springs to adapt blades to working surface conditions. The implement is coupled to the tractor via a swivel hitch, engaging the two lower arms of the rear lift. This coupling makes it possible to perform mowing operations and headland manoeuvring by maintaining the parallelism of created swaths and allowing mower trajectory in alignment with tractor direction. The cutter bar is raised during transport and subsequently lowered by means of a single-effect hydraulic distributor that operates two jacks located in the vicinity of the wheel hub. The cutter bar is fitted with six elliptical cutting discs each fitted with two blades; the disc holder rests on the ground by means of a ground plate. 3

4 The mower is powered by the PTO of a tractor via a cardan shaft which, by means of a reducer fitted with angular drive gear, transmits motion to a secondary shaft, which in turn operates discs via ring-gear transmission. To adjust cutting height it is necessary to use a lever located at the rear of the mower, which permits stepless adjustment from 30 to 80 mm. To the rear of the cutter bar is the conditioning device, consisting of two contrarotating and synchronised grooved rubber rollers. These rollers are moved by a chain drive fitted with a guard. The mower-conditioner is equipped with a swath device consisting of two adjustable deflectors to produce swaths having a width of between 0.90 m and 1.80 m. The cutting technique is based on the counter-rotation of pairs of discs to favour the formation of an even thickness of mown grass and the consequent rapid movement of cuttings towards the conditioner; this is designed to prevent flooding of the conditioner and the possibility of knives cutting stems more than once. Technical data Model FC 243 RTG Series (no.) E Width of cutter bar (mm) 2370 Width of conditioner (mm) 1620 Width during transport (mm) 2545 PTO speed (rpm) 540 Minimum required power (kw) 44 Max. working speed (km/h) 15 Mass (kg) 1475 Tab. 1 General features of FC 243 RTG. Discs (type) oval Discs (no.) 6 Blades per disc (no.) 2 Leading axis of disc (including blades) (mm) Cutting overlaps between discs (mm) ,0 Speed of discs (rpm) 2918 (*) Roller speed (rpm) 986 (*) Peripheral speed of blades (m/s) (*) with the PTO at 540 rpm Tab. 2 Characteristics of cutter bar. Test conditions 79,4 (*) Tests were conducted by the Treviglio Section of the Experimental Institute for Agricultural Mechanisation at its own experimental fields. TRACTOR USED A laboratory-tractor was used for testing. Despite being over-sized in relation to the requirements of the mower-conditioner, the tractor was fitted with the instrumentation needed to measure power absorption at the PTO, work times and consumption, and had the following characteristics: rated power 92 kw total mass 4800 kg hitch device cat. ISO 2 The speed of rotation of the PTO used to operate the mower was set at 540 rpm, with the drive shaft at 2,082 rpm. TEST GROUND Tests were performed on the fourth 4

5 cut of an irrigated multi-species meadow whose vegetation had a mean height of 858 mm. Floral composition was estimated at sight: seasonal development resulted in a greater presence of graminaceous species (about 55% of the total) compared with leguminous and other species (about 25% and 20% respectively). The average dry matter (DM) content in the forage at the time of cutting was 21.0%, while unit output of DM was estimated at 1.16 t/ha. With regard to ground conditions, the test plot was on generally level ground but also contained the slopes needed for irrigation purposes. The soil moisture content at the time of cutting was 36.7%. Fig. 2 gives an overview of the conditions under which the tests were performed. Fig. 2 - Test conditions. After being hitched to the tractor the implement was adjusted as follows: lateral translation of the cutter bar so that it to projected completely beyond the profile of the tractor s rear wheel; alignment of the bar in relation to the forward direction; adjustment of the rear lift spindles to a height of 62 cm from the ground, ideal for the functionality of the implement s swivel hitch; the angle of incidence of the bar in relation to the ground; the cutting height, set to 70 mm. Mowing tests were performed at growing forward speeds ranging from 11 to 15 km/h with a view to identifying optimal working conditions and highlighting speed-related operational limits of the implement. Tests set out to examine the quality of cutting, the machine s working rate and power needs. Results of tests Mowing and conditioning From a sight check mowing appeared to be satisfactory in terms of precision and the absence of stems shredded by repeated and undesirable passages of the blades on the already cut product, demonstrating that the machine can be easily regulated. Despite the working width and mass of the implement, it was observed that the spring-controlled suspension system worked correctly, lightening the cutter bar when there was ground unevenness. The set cutting height remained constant throughout the test, with modest deviations of ± 2 mm on average thanks to the good rigidity of the bar. The maximum working speed under test conditions was between 11 and 13 km/h, but in favourable operating conditions it is possible to reach 15 km/h. The mower-conditioner creates a single trapezoid swath with a constant width, adjustable thanks to the possibility of adjusting the rear swath deflectors which, during tests, were set to form swaths having a mean width of 1126 mm. The set width being equal, the height of the swath depends on the 5

6 productivity of crops. Under test conditions this height was 240 mm on average, with the highest part measured at the centre of the swath. The height of the swath did not obstruct the tractor at any time. The space between swaths, 1100 mm on average, allowed for the regular passage of the tractormower system along the mown strips despite the fact that the size of the trailed implement requires more space for manoeuvres. The efficiency of the conditioning device in the first 6 hours of drying is illustrated in Fig. 3 where the crushing and bending effect of the rollers on stems is observed. Actions was strongly influenced by unfavourable climatic conditions. forage moisture content (%) NC FC 243 RTG Time from mowing (hrs.) Fig. 3 Moisture content in forage samples not conditioned (NC) and conditioned by FC 243 RTG. Working rate Working rate was determined on a regular lengthened strip of land having a length/width ratio of 11.1; this made it possible to minimise time-wasting manoeuvres. A reference speed usable in normal working conditions of 12.2 km/h was considered (Tab. 3), although in optimal working conditions it is possible to reach a speed of 13 km/h. It was also observed that on long and level plots of land the mowerconditioner was able to operate at a working speed of up to 15 km/h, indicated by the manufacturer as the maximum speed thanks to the precalibrated spring-controlled suspension system of the cutter bar, which prevents jolts and consequent jumping off the ground. theoretical working width (mm) 2400 actual working width (mm) 2326 operating working width (mm) 2288 width utilization (%) 98.3 average cutting height (mm) 70 swath width (mm) 1126 swath height (mm) 240 space between swaths (mm) 1100 actual working time (h/ha) 0.29 operating working time (h/ha) 0.32 operating performance (%) 90.6 actual average speed (km/h) 12.2 operating rate (ha/h) 3.1 Tab. 3 Average operating properties of the FC 243 RTG. Power needs Average power requirement was 12.6 kw, with differences of ± 5% depending on the different forward speeds used. Table 4 summarises the main data recorded under test conditions. average engine speed (rpm) 2082 average PTO speed (rpm) 540 average speed (km/h) 12.2 hourly consumption (kg/h) 11.2 unit consumption (kg/ha) 3.6 average PTO torque (Nm) 148 average PTO power (kw) 12.6 average specific power (kw/m) 5.4 Tab. 4 Power needs and consumption. 6

7 As can be seen, the average specific power referring to a single metre mown was due not only to the equipment being tested but also to the good construction of the machine and to the limited productivity of the vegetation, which was undergoing its fourth cut of the summer. Fuel consumption values should however be viewed as approximate in view of the power and state of the tractor used, and thus not attributable solely to the mower. CONCLUSIONS The mower-conditioner with rotary disc and roller conditioner, mod. Kuhn FC 243 RTG, having a theoretical working width of 2.4 m, proved itself to be suitable for use on multispecies meadows, grasslands and leguminous fields. The presence of the roller conditioner made the implement ideal for use in leguminous fields owing to the delicacy with which conditioning operations should be performed on extremely fragile and leafy products. Mowing and the form of the swath were regular, with an even cutting height. Cutting precision depends on the degree of blade sharpening, which should always be checked, and on the correct speed of rotation of discs and forward speed of the tractor. The cutter bar is able to follow the unevenness of the terrain at a forward speed of around km/h, supplying a variable performance depending on the density of the vegetation. Under particularly favourable conditions however it may be possible to reach a speed of 15 km/h, indicated by the manufacturer as the machine s top speed. Finally, coupling of the implement to the tractor and relative working adjustments proved to be simple and easy to carry out. REMARKS AND INSTRUCTIONS The implement is supplied with instruction and maintenance handbook in compliance with existing law provisions. TESTING OF SAFETY REQUIREMENTS The machine possesses CE marking, an identification plate, safety pictograms, a user and maintenance handbook and an EC manufacturer s declaration of conformity. The EC manufacturer s declaration of conformity certifies that the machine conforms to the following harmonised standards and technical specifications: UNI EN 745:2002; UNI EN 1553:2001; ISO 11684:1995. Checks carried out with reference to documentation sent by the manufacturer did not show up inconsistencies with the contents of the aforementioned standards. The relative documentation was filed. MODELS IN THE SAME SERIES On the basis of test results it may be stated that for all machines in the RTG series the quality of work performed is very similar, while the working rate and absorption of power may vary. These properties may be approximately gauged by the data given below compared with the model tested. Model FC 283 RTG Working width (mm) Mass (kg) Serial no A0020 Tab. 5 Other models in the same series. 7

8 THE PRESENT REPORT IS VALID FOR A PERIOD OF FIVE YEARS OR UNTIL REFERENCE REGULATIONS FOR THE MOWER-CONDITIONER MOD. FC 243 RTG AND RELATIVE EXTENSION ARE ALTERED, AND IS OFFICIALLY RECOGNISED BY ENAMA MEMBERS: ASSOCAP (Associazione Nazionale dei Consorzi Agrari) (National Association of Farm Consortia) CIA (Confederazione Italiana Agricoltori) (Italian Farmers Confederation) COLDIRETTI (Confederazione Nazionale Coltivatori Diretti) (National Confederation of Independent Farmers) CONFAGRICOLTURA (Confederazione Generale Agricoltura) (General Farming Confederation) UNACMA (Unione Nazionale Commercianti Macchine Agricole) (National Union of Farm Machine Dealers) UNACOMA (Unione Nazionale Costruttori Macchine Agricole) (National Union of Farm Machine Manufacturers) UNIMA (National Union of Farm Mechanisation Enterprises) (National Union of Farm Mechanisation Enterprises) AND BY MEMBERS OF THE EXECUTIVE COUNCIL OF THE ENAMA, IN WHICH THE FOLLOWING ARE ALSO REPRESENTED: MIPAF (Ministry for Agricultural and Forestry Policies) Regions and Autonomous Provinces ISMA (Istituto Sperimentale per la Meccanizzazione Agricola) (Experimental Institute for Farm Mechanisation) ENAMA - ENTE NAZIONALE PER LA MECCANIZZAZIONE AGRICOLA VIA LAZZARO SPALLANZANI, 22/A ROME TEL. 06/ FAX 06/ info@enama.it