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1、International Standard m 72561 1 0 a 4 4!g!ib sNTERNAT,ONAL ORGANlZATlON FOR STANDARDIZATIONMEmAYHAPOAAfl OPTAHHJAUMR n0 CTAHAAPTM3AUklM*ORGANlSATlON INTERNATIONALE DE NORMALISATION Sowing equipment - Test methods - Part 1 : Single seed drills (precision drills) Matbrie de semis - M the main objecti
2、ve being comparability for any one model of equipment. This condition of reproducibility limits the number of man- datory tests which can be used and eliminates mandatory tests in the field. However, these tests may be carried out optionally at the instigation of the test office or at the request of
3、 the manufacturer. 1 Scope and field of application This part of IS0 7256 specifies test methods for single seed drills (precision drills). 2 Reference IS0 7424, Agricultural equipment - Matching of wheeled trac- tors and rear mounted implements - Code numbering system. NOTE - A future International
4、 Standard will deal with classification and terminology of equipment for sowing and planting. 3 Definitions For the purpose of this part of IS0 7256 the following defi- nitions apply. 3.1 single seed drills (precision drills) : Drills whose meter- ing mechanism distributes seeds singly by means of a
5、 burying device at predetermined intervals to form a sowing line. NOTE - As the great majority of sowing equipment has equidistant spacings, the tests refer only to this type of equipment. 3.2 sowing unit (for seed): Unit generally comprising the metering mechanism and the burying device. 3.3 meteri
6、ng mechanism (for seed): Mechanism which takes seeds from a batch leaving the hopper individually or in groups and deposits them in a line (or row). 3.4 burying device : Device generally comprising a coulter, a device to regulate the ground penetration depth of the coulter and a unit that covers the
7、 seed. 3.5 coulter: Device for opening a furrow in the ground in which the seeds leaving the metering mechanism are placed. 3.6 flow rate: Amount of seed distributed, expressed as a number, mass or volume of seed per unit of time.1) 3.7 application rate: Amount of seed distributed, ex- pressed as a
8、number, mass or volume of seed per unit of length or surface.1) 3.8 spacing : The distance between two successive seeds in the row. theoretical spacing : Spacing set on the control mechanism and stated by the manufacturer. 3.9 miss : For a single seed drill, the absence of a seed where there should
9、be one theoretically. In practice, by analogy with statistical evaluation of results, all spaces larger than 1,5 times the theoretical seed spacing are considered to be misses (see 6.1.1). 3.10 multiples : For a single seed drill, the presence of two seeds or more where there should only be one. In
10、practice, by analogy with statistical evaluation of results, all spacings less than 0,5 times the theoretical seed spacing are considered to be multiples (see 6.1 .I). 1) For precision drills, only the number is to be taken into consideration for flow rate and application rate measurements. 1 Copyri
11、ght International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/20/2007 07:31:04 MDTNo reproduction or networking permitted without license from IHS -,-,- IS0 7256/l-1984 (E) 4 General test conditions 4.1 See
12、d drill 4.1.1 Selection The seed drill to undergo testing may be selected by the representative of the test office in agreement with the manufac- turer. The seed drill shall, in all respects, conform strictly to the specifications, which the manufacturer is required to send to the test office in wri
13、ting. The test report (see annex F) shall specify how the drill to be tested was chosen. 4.1.2 Manufacturer s instructions Use the drill in accordance with the manufacturer s instruc- tions, which shall specify, among other things a) the maximum forward speed and, if appropriate, the minimum forward
14、 speed, expressed in metres per second ; b) the maximum, and if appropriate, the minimum number of revolutions, expressed in minutes to the power of minus one (min - 1). and/or peripheral speed, expressed in metres per second, of the metering mechanism ; cl the species and types of seed which may be
15、 sown; d) the metering mechanisms suited to each seed species. 4.1.3 Checking of specifications The technical characteristics supplied by the manufacturer shall be indicated in the test report and shall be checked. 4.2 Seed 4.2.1 Types The tests shall be carried out taking into account the manufac-
16、turer s specifications. 4.2.1.1 Single-purpose drill If the seed drill is stated to be specifically for one or more types of seed and/or distribution methods, the test shall be carried out exclusively with the seeds indicated by the manufacturer, and, as appropriate, of the size specified. 4.2.1.2 M
17、ultipurpose drill If the drill is stated to be multipurpose, the tests shall be carried out with the following four types of seed : - type a: a medium size round seed 3 + 0,75 mm in diameter (for example, pea or a coated seed the coating of which shall be smooth and of a regular shape); - type b: a
18、small seed of regular shape (for example, cabbage) of diameter less than 3 mm ; - type c : a large irregular seed (for example, bean or flat maize seeds) of diameter greater than 6 mm; - type d: the most difficult seed permitted by the manufacturer (for example unpelleted genetically mono- germ beet
19、 seed, carrot, etc.). NOTE - The seeds shall not have been subjected to any treatment which could change their physical properties, except that incorporated in the coatings. 4.2.2 Characteristics The dimensional characteristics (scale and granulometric pro- file), purity (percentage of foreign bodie
20、s, bad seeds and broken seeds) and water content of the batch of seeds used shall be noted in the test report. 4.3 Ambient conditions The hygrometric levels shall be observed and noted in the test report. 5 Mandatory tests 5.1 Nature of test (see annex A) The mandatory tests deal essentially with th
21、e precision of seed planting and the efficiency of metering. Each test shall be carried out with three different units, either three units on one multirow drill or three independent sowing units if each one has a metering mechanism. Tests 1, 2, 3 and 6 (see annex A) shall be carried out with the sow
22、ing unit either static or mobile. Test 4 (see annex A) shall be carried out with the sowing unit mobile. Test 5 (see annex A) shall be carried out with the sowing unit moving over a bed of sand. 5.1.1 Static tests With the sowing unit stationary, the metering mechanism shall be driven at a rotary sp
23、eed equal to that which it would have for actual work, i.e. taking into account the theoretical forward speed and the adjustment of the ratio between the metering mechanism and the driving wheel speeds. In order to simulate the relative movement of the drill above the ground, an 1) For optional test
24、s see annex E. 2 Copyright International Organization for Standardization Provided by IHS under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/20/2007 07:31:04 MDTNo reproduction or networking permitted without license from IHS -,-,- IS0 7256/l-1984 (El adhesive s
25、trip moving at the relative forward speed of the drill when travelling without slipping may be run underneath the seed drill. NOTE - This recording on to an adhesive strip may be replaced by any other recording method, such as an acoustic or optical method. The method used shall be noted in the test
26、 report. 5.1.2 Mobile test The sowing unit shall be fixed to a mobile trolley moving at a constant speed and without jolting over a stationary adhesive strip. NOTE - Recording by means of an adhesive strip may be replaced by any other recording method, such as an acoustic or optical method. The meth
27、od used shall be noted in the test report. 51.3 Test on a bed of sand The sowing unit shall move over a bed of sand of specified characteristics (see the note) at a constant speed and without jolting. The coulter shall penetrate this sand to a depth at least equal to the minimum working depth. For t
28、his test, the coulter may be equipped with deflectors which, without interfering with the placing of the seeds, pre- vent the sand from falling back. It shall be maintained at a con- stant depth. The forward speed shall be equal to the actual speed of the seed drill at work. NOTE - Characteristics o
29、f the sand may be as follows: a) foundry sand : - granulometry of 85 to 120 urn, - clay content intended to provide a binding agent (20 to 25 %), - water content between 4 and 6 % ; b) a pure sand (such as Fontainebleau sand to which a low- viscosity oil is added in the proportion of 1 %). 5.2 Adjus
30、tments and procedure 5.2.1 Position of the coulters (see annex A) Tests 1, 2 and 6 (see annex A) may be carried out with the coulters raised, on the recommendation of the manufacturer. The distance between the metering mechanism seed outlet and the impact surface shall be as close as possible to tha
31、t in actual practice between the seed outlet and the bottom of the furrow. Test 3 (see annex A) shall be carried out partially with the coulter in position so as to check whether there is any seed re- bound against the coulter wings. If so, the distance between .the metering mechanism outlet and the
32、 impact surface shall be slightly greater, but still as close as possible to the actual distance so as not to extend the seed fall distance unduly. This distance shall be noted in the test report. Tests 4 and 5 (see annex A) shall be carried out with the coulter in position. 5.2.2 Filling the hopper
33、s The hoppers shall be filled at the time of the test, avoiding any abnormal compaction of the seed. For the tests with the hopper full, half full and one eighth full, these volumes correspond to 100, 50 and 12,5 % of the total volume of the hopper plus the usable volume of the metering mechanism fe
34、ed chamber. 5.2.3 Forward speed Three relative drill/ground speeds shall be chosen corre- sponding to the forward speeds from the range 1 ; 1,50; 2; 2,50 and 3 m/s in accordance with the manufacturer s instructions. For static tests, if the driving wheel is mounted on tyres, the rotary speed o is gi
35、ven by the equation V a=- 2nR where v is the relative forward speed; R is the radius of the tyre under average load. 5.2.4 Adjustment of the metering The tests shall be carried out with the average spacings currently used in agriculture for these types of seeds. These metering amounts shall be recor
36、ded in the test report. 5.2.5 Speed adjustment of the metering mechanism As the seed spacing control is obtained by a combination of the number of the holes or cells of the metering mechanism and its rotary (or linear) speed, the tests shall be carried out at maximum and minimum speeds and at the in
37、termediate speed closest to the mean arithmetical speed between the maximum and minimum speeds specified by the manufacturer for the type of seed to be tested, adjusting the metering member (drum, disc or belt) on the sowing unit for the particular spacings. If there is only one means of adjusting t
38、he spacing, the test shall only be carried out with this one setting. 5.2.6 Slope test The slope tests shall be as follows : a) ascending a slope : incline the sowing unit 11 o towards the rear (corresponding to a 20 % slope); 3 Copyright International Organization for Standardization Provided by IH
39、S under license with ISO Licensee=NASA Technical Standards 1/9972545001 Not for Resale, 04/20/2007 07:31:04 MDTNo reproduction or networking permitted without license from IHS -,-,- IS0 7256/l-1984 (E) 5.3.4 Effect of the forward speed of the seed drill (test 41 b) descending a slope: incline the so
40、wing unit 1 lo towards the front ; Determine whether this speed has an effect on the feeding of the metering mechanism and on the spacing precision. c) slope to the right : incline the sowing unit ll” to the right ; 5.35 Effect of the unwanted movements of seeds (test 5) d) slope to the left : incli
41、ne the sowing unit 1 I0 to the left. Check whether such movements exist (rotation of the seed) and whether they have an effect on planting accuracy. 5.2.7 Duration of the tests The number of runs may vary according to the length of the test bench. They shall cover a total workable distance cor- resp
42、onding to a minimum of 250 seeds in situ. 5.3.6 Effect of the separation of the seeds (test 6) Check if there is any seed separation in the hopper and whether it has an effect on the feeding. For each run on the test bench (mobile test) or each run on a mobile strip (static test), disregard an appro
43、priate length to cancel out irregularities resulting from initial acceleration. NOTE - Before the test the metering mechanism should be rotated for 30 min feeding it constantly with new seeds from the batch to be tested and never letting the level in the hopper fall to below l/8 of its capacity. The
44、 test is then carried out with the seeds remaining in the bottom of the hopper (filled to l/8 capacity). Before each test for which the hopper is filled, rotate the meter- ing mechanism sufficiently to allow the seed flow to fill the feed chamber of the distributing mechanism. 6 Test results 5.2.8 M
45、easuring procedure 6.1 Results of mandatory tests The measurements relate solely to the distance between the seeds, both in the static and mobile tests. The unit of measure- ment shall be the millimetre, the spacing between two seeds being measured from the geometric centres of two consecutive seeds
46、. Add the figures for each run to obtain one result per test; thus tests on three sowing elements shall give three results for each test (one per unit). 6.1.1 Processing of data 5.3 Test procedure (see annex A) 6.1.1.1 The adjustment of the seed drill in accordance with the manufacturer s instructio
47、ns gives the theoretical seed spacing xref. This theoretical spacing shall be verified by the testing office. 5.3.1 Effect of the level of seeds in the hopper (test II Determine whether the level of seeds in the hopper has an effect on the feeding of the metering mechanism. 6.1.1.2 The measurement c
48、heck gives the different values x for the spacing between successive seeds during the test. 6.3.2 Effect of the adjustment of the speed of the metering mechanism (test 2) 6.1.1.3 These different values of x are divided up into segments equal to 0,l xrer distributed on either side of xrer. Thus the i
49、ntervals obtained around xref are as follows : Determine whether this speed has an effect on the feeding of the metering mechanism. 5.3.3 Effect of the position of the apparatus working on slopes (test 3) 6.1.1.4 Each segment is allocated the variable 5.3.3.1 Ascending and descending slopes xi = 3. Xref Determine whether these slopes have an effect on the feeding of the metering mechanism. where Xi is the median of the segment. 6.1.1.5 The following