Prüfberichts-Nummer I-5139 TEST REPORT No. 03c 002

Transcription

1 FARM MACHINERY FUNCTIONAL AND SAFETY TESTING SERVICE Prüfberichts-Nummer I-5139 TEST REPORT No. 03c 002 GB BLADES (VERSION 2002) FITTED TO HARROW KNIVES SICMA ADLER ADS 5000 ROTARY HARROW ACCESSORY MANUFACTURER: GIOVANNI BURATO Via Marocchesa, Mogliano Veneto (TV) HARROW MANUFACTURER: SICMA S.P.A. VIA F.LLI LOMBARDI, OSTRA VETERE (AN) Rome, November /8

2 TESTS CARRIED OUT IN COMPLIANCE WITH ENAMA SPECIFICATIONS NO. 03C BY ISTITUTO SPERIMENTALE PER LA MECCANIZZAZIONE AGRICOLA (EXPERIMENTAL INSTITUTE FOR FARM MECHANISATION), MONTEROTONDO - ROME: Supervisor Technical tests Collaborators Ing.Giovanni Santoro Dott.Agr.Roberto Fanigliulo Dott. Agr.Daniele Pochi Mr. Gino Brannetti Mr. Cesare Cervellini TABLE OF CONTENTS DESCRIPTION OF MACHINE 3 Installation procedure 3 TECHNICAL DATA 3 TEST CONDITIONS 3 Tractor used 4 Instrumentation used 4 RESULTS OF TESTS 5 NOTES ON FUNCTIONALITY 7 TO FACILITATE INTERPRETATION OF THE RESULTS, IT SHOULD BE REMEMBERED THAT: 1 MPa = 1000 kpa = 10 bar 10 kg force /cm 2 1 dan 1.02 kg force 1 kw = 1.36 CV 1 m/s = 3.6 km/h rpm =giri -1. 2/8

3 DESCRIPTION OF MACHINE The tillage machine accessory GB blades consists of a pair of rectangular steel blades. The blades are designed to make a better job of breaking up surface lumps of earth during the rotarytranslational movement of the working harrow blades and of removing weeds through horizontal cutting of undesired plants at the neck and root system levels (fig. 1). Installation procedure The blades are welded perpendicularly onto the outer side of each knife of a rotary harrow, at a height of 70 and 140 mm respectively from the bottom of the TECHNICAL DATA right knife and at a height of 60 and 130 mm from the bottom of the left knife. Fig.1 Close-up of GB blades and welding points on knife. type rectangular steel blade number per knife 2 number per rotor 4 total number 80 width (mm) 29.5 length (mm) 36.5 thickness (mm) 6 position perpendicular, on the outer side of each knife, welded at varying heights from the bottom of the knife; TEST CONDITIONS The accessory was subjected to working tests, being fitted to a rotary harrow produced by the firm Sicma (Mod. ADLER ADS 5000), at the farm estate of the Istituto Sperimentale per la Meccanizzazione Agricola (Experimental Institute for Farm Mechanisation) at Monterotondo, Rome, in October Refer to certificate for a description of the harrow used for testing and relative technical data. 3/8

4 Tractor used To pull the trailer a 4-wheel drive tractor having the following characteristics was used: rated power 205 kw total mass kg hookup device cat. 3 ISO The PTO speed was selected at 1000 rpm (corresponding to 1974 rpm of drive shaft). Instrumentation used For field tests an instrument chain formed by a series of sensors fitted to the tractor was used: a torquespeedometer with relative signal conditioning unit to measure driving torque and the speed of rotation of the tractor s PTO; a digital encoder to measure the number of turns of the tractor s rear wheels, used to calculate wheel slip; a strain gauge type monoaxial load cell, in traction and compression, to measure the pull required by the trailer. The unit was fitted between the tractor to which the trailer was attached and a brake-van, which pulled the former at a typical working speed. The torque-speedometer was calibrated in two stages, one to measure speed and one to measure torque, using the configuration software installed on the tractor s PC. It was thus possible to check, at several points, the consistency of PTO rotation speed measurements with actual values measured using a precision tachometer. With reference to the functioning of the circuit to measure drive torque, it was possible to ascertain the correct value of the calibration signal from the transducer. The torque measuring circuit was calibrated by placing known masses onto an arm attached to the shaft issuing from the same instrument. The load cell used was calibrated by placing known masses onto the hookup point after having hung the device in a vertical position, and making several readings, checking the reading with the ad hoc configuration software of the data recorder. The encoder was calibrated by making a full turn of the tractor s rear drive wheel, to which the encoder was attached, checking the correct reading of pulses from the instrument using the ad hoc configuration software of the data recorder. Fig. 2 The test area prior to testing. TEST GROUND The test area was formed by a series of strips of unploughed flat soil. The remains of wheat crops and weeds were present on the surface (Fig. 2), with a mean terrain coverage of 78.8%. This index was calculated on the basis of the ratio: overlaps occurring between grid nodes and the surface remains of crops, with the total number of grid nodes having a size of 1 m 2 and side meshes of 100 mm. Prior to harrowing the following were measured: granulometric composition, relative humidity (from m to m) and the apparent mean density of the soil; penetration resistance for the layer being harrowed (from 0 to 0.3 m) (table 1). 4/8

5 skeleton (%) 0 sand (%) 2.3 silt (%) 43.4 clay (%) 54.3 liquid limit (%) 62.2 plastic limit (%) 40.3 plasticity index 21.9 humidity 0 m 0.2 m (%) 19.3 humidity 0.2 m 0.4 m (%) 21.0 mean density apparent (g/cm 3 ) 1.35 mean penetration resistance (MPa) 0.97 Table 1 Physical-mechanical properties of test ground. RESULTS OF TESTS After having established the most appropriate gear for the tractor (1 st ), inserted double traction and the differential locking mechanism and moved the accelerator lever to the top, the functional and operational characteristics (referring to one hectare) of the tractor-trailer-accessory system were determined. Table 2 shows the results of two series of tests performed on unploughed soil at the same tilling depth, with the rotary harrow used firstly with tools endowed with GB blades and then with tools not having the same accessory. The results of soil crushing tests for the harrow working on unploughed soil under various test conditions are given in the diagrams in figure 5. The size classes of lumps of earth are given in mm. Table 2 shows a specific traction force of approximately 17.7 dan/m.cm and 12.3 dan/m.cm respectively for the 1 st and 2 nd tests, resulting in a significant absorption of pull power of 10.9 kw and 7.1 kw respectively, operating at an adequate vehicle speed, such as to obtain the best performance in terms of soil improvement. Tractor wheel slip was modest and within normal limits for the type of equipment being tested. In both tests it was seen that 98.8% of the maximum working width was used, while the thickness of the layer harrowed was 0.13 m for the test with GB blades fitted and 0.12 m for that without GB blades. It may be seen in figure 5 that the passage of the harrow produced a good soil improvement index of for harrowed soil using GB blades, as compared with for the test without GB blades. It also removed the first clod size classes and took clod classes below 10 mm to 54% and 43% respectively of all crushed soil. The consequent seed bed quality index (ratio: mass of clods having a diameter 10 mm/mass of clods having a diameter > 10 mm) was calculated as being 1.08 in the test with GB blades and 0.88 in the test without GB blades, thus ensuring an adequate substratum for sowing and subsequent germination. The combined effect of rotary tools and the packer roller produced a good levelling of the soil in all tests, determining a surface rugosity index of in the 1 st test and in the 2 nd. The quality of work performed, with particular reference to the use of GB blades, was assessed by measuring also the degree of coverage of hard ground and harrowed ground, obtained from the ratio of the surface covered by plant biomass and total soil surface, thus determining the degree of biomass interment, which in the test using GB blades amounted to 84.3%, and in the test without GB blades was 76.6%. Checks carried out 20 days later on the same strips of soil tilled by the rotary harrow showed a significant increase in the soil coverage index for the area in 5/8

6 which GB blades were not used (from 18.58% to %) (Fig. 3), while for the test in which the Sicma harrow was endowed with GB blades (Fig.4), the rise in this index was less marked (from 12.27% to 16.32%). Elements 1 st test hard ground with GB blades 2 nd test hard ground without GB blades mean engine speed (rpm) mean PTO speed (rpm) mean rotor speed (rpm) theoretical working width (m) real working width (m) operational working width (m) use of working width (%) depth of harrowed layer (m) harrowed section (m²) hard ground coverage index % harrowed ground coverage index % real working time (h/ha) operational working time (h/ha) operational performance (%) actual mean speed (km/h) operational field capacity (ha/h) hourly fuel consumption (kg/h) unit fuel consumption (kg/ha) mean traction force (dan) mean PTO torque (danm) mean PTO power (kw) mean traction power required by work* (kw) total mean power required (kw) specific mean power (kw/m.cm) tractor wheel slip (%) Table 2 Mean results obtained using rotary harrow (*) Global power expended for machine traction, excluding losses of transmission due to idle state, wheel slip and the power required for the tractor s hydraulic functions. 6/8

7 Figure 3 Test area without GB blades 20 days after test. 43% A 9% 17% > <10 Figure 4 Test area with GB blades 20 days after test. B 7% 16% > <10 54% 23% 31% Figure 5 Clod level of the soil after passage of harrow not endowed with GB blades (diagram A) and after passage of harrow endowed with GB blades (diagram B). NOTES ON FUNCTIONALITY The combination of the GB blade accessory with the ADLER ADS 5000 rotary harrow produced by the firm Sicma Macchine Agricole is a good solution for the enhanced control of weeds after tilling and for an adequate level of soil improvement. The horizontal cutting action of these blades removes weeds more efficiently. Crops sown after the soil has been harrowed with GB blade-endowed tools are thus at an advantage in relation to weeds which, having been removed by the harrow and cut up by the blades under review, find it more difficult to reemerge, as shown by the soil coverage index 20 days after field testing. This aspect makes it possible to reduce the use of chemical weed-killers, with a consequent drop in environmental impact. The rotary harrow, furthermore, endowed with GB blades, produced good soil improvement, confirming results obtained in a previous test on ploughed soil (ENAMA certificate no. 03c-001), with a significant rise in the percentage of clods less than 10 mm in size (54% of total crushed soil), despite working on unploughed soil. This allows for an improvement in the conditions needed to prepare a suitable seed bed, even in working conditions deemed to be difficult, since a very fine layer of soil is created immediately beneath the surface, constituting an excellent ground for rapid seed germination. On the surface there remained a greater degree of clod level, important in reducing crust formation, in the event of rain, during the critical phase for plant growth. 7/8

8 THE PRESENT TEST REPORT IS VALID FOR A PERIOD OF FIVE YEARS OR UNTIL REFERENCE REGULATIONS FOR THE GB BLADES VERSION 2002 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 (Unione Nazionale Imprese Meccanizzazione Agricola) (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) 8/8 ENAMA - ENTE NAZIONALE PER LA MECCANIZZAZIONE AGRICOLA (Italian Farm Mechanisation Body) VIA LAZZARO SPALLANZANI, 22/A ROME - ITALY TEL. 06/ FAX 06/ info@enama.it pag. 8/8