1、BRITISH STANDARD BS 6978-2: 1990 ISO 7256-2: 1984 Seed drills Part 2: Methods of test for seed drills for rowsBS6978-2:1990 This British Standard, having been prepared under the directionof the Agricultural Machinery and Implements Standards Policy Committee, waspublished under the authorityof the B
2、oard of BSIandcomes into effect on 30June1990 BSI 12-1999 The following BSI references relate to the work on this standard: Committee reference AGE/32 Draft for comment83/70338DC ISBN 0580182886 Committees responsible for this BritishStandard The preparation of this British Standard was entrusted by
3、 the Agricultural Machinery and Implements Standards Policy Committee (AGE/-) to Technical Committee AGE/32, upon which the following bodies were represented: A F R C Institute of Engineering Research Agricultural and Allied Workers National Trade Group Agricultural Engineers Association British Flu
4、id Power Association Department of Transport Fertiliser Manufacturers Association Ltd. Health and Safety Executive Local Authority Organizations Ministry of Agriculture, Fisheries and Food National Farmers Union Silsoe College Amendments issued since publication Amd. No. Date CommentsBS6978-2:1990 B
5、SI 12-1999 i Contents Page Committees responsible Inside front cover National foreword ii 0 Introduction 1 1 Scope and field of application 1 2 References 1 3 Definitions 1 4 General test conditions 1 5 Mandatory tests 2 6 Test procedure 4 7 Results 4 8 Test report 4 Annex A Programming of mandatory
6、 tests 5 Annex B Optional tests 6 Annex C Example of test report on a seed drill for sowing in lines 8 Table 1 5 Table 2 7 Table 3 10 Table 4 11 Publication referred to Inside back coverBS6978-2:1990 ii BSI 12-1999 National foreword This British Standard has been prepared under the direction of the
7、Agricultural Machinery and Implements Standards Policy Committee and implements agreements of the International Organization for Standardization (ISO). It is identical with ISO7256-2:1984 “Sowing equipment Test methods Part2:Seed drills for sowing in lines”. ISO 7256-1 deals with single seed drills
8、(precision drills) and has been published as BS6978-1. The Technical Committee has reviewed the provisions of ISO3339-0, ISO3339-4, ISO3534, ISO5698, ISO5699 and ISO7424, to which reference is made in the text and has decided that they are acceptable for use in conjunction with this standard. A Brit
9、ish Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Cross-reference International Standard Correspo
10、nding British Standard ISO 3534:1977 BS 5532 Statistical terminology Part 1:1978 Glossary of terms relating to probability and general terms relating to statistics (Identical) Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages2 to 12, an inside back
11、cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.BS6978-2:1990 BSI 12-1999 1 0 Introduction The aim of this part of ISO7256 is to make available to test office
12、s and other interested organizations a standardized test method permitting reproducibility of tests when they are carried out in geographically remote areas and/or in different climatic conditions; the main objective being comparability for any one model of equipment. This condition of reproducibili
13、ty limits the number of mandatory 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 the manufacturer. The test method takes into account the effects of the type of seed, t
14、he level of seed in the hopper, the application rate adjustment, the forward speed, the slope of the ground and the condition of the soil surface (bumps). 1 Scope and field of application This part of ISO7256 specifies a test method for seed drills for sowing in lines, including seed drills attached
15、 to a basic machine. The test method permits the determination of performance using reproducible tests so that comparable results in numerical or graphical form which take into account the influence of the following can be obtained: type of seed; the forward speed; the level of seed in the hopper; t
16、he application rate adjustment; the slope of the ground; the condition of the soil surface (bumps). Optional tests (seeAnnex B) may supplement the test method by taking into account the effects of products used for treatment and distribution on the sowing site. The mandatory tests do not give any pi
17、cture of the true distribution of the seeds on the sowing site. NOTEPart 1 of ISO7256 deals with single seed drills (precision drills). (See ISO3339-0 for the classification.) 2 References ISO 3339-0, Tractors and machinery for agricultureand forestry Classification and terminology Part0: Classifica
18、tion system and classification. ISO 3339-4, Tractors and machinery for agricultureand forestry Classification and terminology Part4: Sowing and planting equipment 1) . ISO 3534, Statistics Vocabulary and symbols. ISO 5698, Agricultural machinery Hoppers Manual loading height. ISO 5699, Agricultural
19、machines, implements and equipment Dimensions for mechanical loading with bulk goods. ISO 7424, Agricultural equipment Matching of wheeled tractors and rear mounted implements Code numbering system. 3 Definitions For the purpose of this part of ISO7256, the following definitions apply. 3.1 seed dril
20、ls for sowing in lines see ISO3339-4 3.2 feed mechanism (for seed) a mechanism which takes seed from a hopper and transfers it at a constant determined flow rate into a furrow created by the coulter 3.3 flow rate (of seed) the quantity, expressed as mass or volume, of seed sown per unit time 3.4 app
21、lication rate (of seed) the quantity, expressed as mass or volume, of seed sown per unit length or unit area 3.5 hopper height the internal height of the hopper, H, shall be the vertical distance between the lower edge of the outlets and the lower edge of the top of the hopper 4 General test conditi
22、ons NOTEThe manufacturer or his representative should be entitled to be present at the tests. 4.1 Seed drills 4.1.1 Selection The seed drill to undergo testing may be selected by the representative of the test office in agreement with the manufacturer. 1) At present at the stage of draft.BS6978-2:19
23、90 2 BSI 12-1999 The seed drills shall, in all respects, conform strictly to the specifications which the manufacturer is required to send to the test office in writing. The test report (seeAnnex C) shall specify how the seed drill to be tested was chosen. If the test on the seed drill is associated
24、 with a test on a basic machine, the seed drill chosen shall be that attached to the basic machine to be tested. 4.1.2 Manufacturers instructions 2) Use the seed drill in accordance with the manufacturers instructions, which shall specify, among other things a) the maximum working speed, expressed i
25、n kilometres per hour or in metres per second; b) the types of seed which the seed drill can sow or discharge; c) in the case where the device includes several interchangeable mechanisms, the types of feed mechanism and types of seed which can be sown or discharged by each model; 3) d) the maximum a
26、nd minimum application rates permitted by the feed mechanism(s) for each type of seed; e) any accessories which may be required for distributing certain types of seed; f) the inflation pressure, if the seed drill or the basic equipment is fitted with pneumatic tyres. 4.1.3 Checking of specifications
27、 The technical characteristics supplied by the manufacturer shall be checked and shall be noted in the test report. When comparing laboratory test results with application rate and flow rate data supplied by the manufacturer, it shall be noted that manufacturers data may have been adjusted for wheel
28、 slippage. 4.2 Seed 4.2.1 Types Each of the performance tests shall be carried out with the following seeds: type a: an average size seed of regular shape, wheat (mandatory); type b: a small round seed (for example clover); type c: a light bearded seed (for example rye-grass from Italy); type d: a l
29、arge, irregular shaped seed (for example field bean). If the manufacturer judges his seed drill to be unsuitable for the sowing of one or more types of seed, these types will be excluded from the tests and the fact noted in the test report. NOTEFor the mandatory reproducible tests, these seeds shoul
30、d not have been subjected to any treatment (with phytosanitary or other products) likely to modify their physical characteristics. 4.2.2 Physical characteristics The seed used shall be of current commercial quality. The dimensions, germination percent, bulk density, mass of1000seeds, purity (percent
31、age of foreign bodies, broken seed and bad seed), and the water content of each batch shall be noted in the test report. 4.3 Ambient conditions The degree of atmospheric humidity shall be noted in the test report. 5 Mandatory tests 4) 5.1 Nature of tests (seeAnnex A) The essential aim of these tests
32、 is to determine the evenness of the flow rate and the accuracy of metering. These tests shall be carried according to two methods: static tests; mobile tests; to give the appropriate results. 5.1.1 Static tests With the seed drill stationary, the drive wheel shall rest on a drive mechanism. It shal
33、l be driven at a speed equal to that which it would have in actual operation, that is at the theoretic forward speed of the seed drill travelling without slipping. 5.1.2 Mobile tests The seed drill shall be driven at a constant speed on a hard and uniform surface. An adhesive strip, or visual or aco
34、ustic processes shall be laid on the surface over which the seed drill passes. 5.2 Distance between the feed mechanism and the surface Care shall be taken that the mechanism is placed, in relation to the surface (for example an adhesive strip), at an average distance corresponding to that in actual
35、operation. 2) These instructions shall be attached to the test report. 3) Applicable to seed drills for ergot. 4) For the optional tests, seeAnnex B.BS6978-2:1990 BSI 12-1999 3 5.3 Types of tests 5.3.1 Evenness of flow rate The test shall be carried out with the machine stationary. The seed shall be
36、 collected in separate troughs placed under each feed mechanism or coulter. 5.3.2 Accuracy of metering If the test has to be carried out with the machine stationary, in order to establish the relative seed drill/ground displacement, a suitable method shall be used; for example an adhesive strip shal
37、l be passed under the coulter, which will move in the opposite direction to the direction of movement of the seed drill at the theoretic speed of the seed drill travelling without slipping. The seed shall be deposited on the adhesive strip and shall be counted. The method shall be noted in the test
38、report. If the test has to be carried out with the machine mobile, it shall be moved over a fixed adhesive strip laid on the surface. The seeds shall be deposited on the adhesive strip and shall be counted. 5.3.3 Metering tests with bumps To simulate bumps, place, along the course of each wheel of t
39、he equipment, a series of obstacles of height50mm and length200mm, preceded by a150mm ramp and placed in such a way that the obstacles are met with simultaneously by both wheels. Each course shall include at least three pairs of obstacles distributed over its length so that the distance between two
40、obstacles is not less than4m. 5.4 Adjustments and measurements 5.4.1 Selection of feed mechanisms 5.4.1.1 Flow tests Each test shall be carried out simultaneously on all feed mechanisms of the seed drill. 5.4.1.2 Application rate tests Each test shall be carried out simultaneously or successively on
41、 three feed mechanisms, one at the centre and one at each end of the seed drill. 5) 5.4.2 Filling the hopper Load the seed, in accordance with the specifications of the manufacturer, into the hopper immediately prior to testing so that there is no time for settling or consolidation. 5.4.3 Forward sp
42、eed The speeds of the seed drill relative to the ground, corresponding to normal working speeds, shall be1,50m/s,2,50m/s, and the maximum admissible speed. If one or more of these speeds is considered unacceptable by the manufacturer, it shall be replaced by one recommended by the manufacturer; ment
43、ion of this shall be made in the test report. For static tests, if the driving wheel is mounted on tyres, the rotary speed, , is given by the equation where v is the speed of travel; R is the radius of the tyre under average load. 5.4.4 Adjustment of application rates The tests shall be carried out
44、at three rates: a) minimum: the minimum rate given by the manufacturer; b) maximum: the maximum rate given by the manufacturer; c) mean: arithmetic mean of the minimum and maximum rates. If a mean rate cannot be obtained within the range of adjustments of the seed drill, take the nearest rate which
45、this range of adjustments allows, and note this in the test report. 5.4.5 Slope tests The slope tests shall be carried out as follows: a) ascending a slope: incline the seed drill11 towards the rear (corresponding to a20% slope); b) descending a slope: incline the seed drill11 towards the front; c)
46、slope to the right: incline the seed drill11 to the right; d) slope to the left: incline the seed drill11 to the left. 5.4.6 Duration of metering tests The number of tests may vary according to the length of the test rig, which shall provide an overall effective length of30m. Before each reading a s
47、ufficient time shall be allowed for cancelling out the unevennesses due to starting up accelerations and to allow the establishment of flow of the seed through the spout of the feed mechanism. 5) In the case of multirow equipment.BS6978-2:1990 4 BSI 12-1999 5.4.7 Taking measurements 5.4.7.1 Flow rat
48、e test The seeds collected in a trough shall be weighed. Five runs lasting30s shall be made for each test. 5.4.7.2 Metering test Measurement shall be carried out by counting the seeds deposited. Where measurement is to be noted, divide the strip into sections of100mm in the direction of the length,
49、and record the number of seeds contained in each section. NOTE 1When an adhesive strip is used, it is useful, before adhesive is applied, to draw parallel lines on the strip100mm apart perpendicular to the direction of forward movement. NOTE 2In the case of visual or acoustic processes, a graphic means of recording on recording tape is generally used. The tape shall be cut into sections of length corresponding to the time necessary for the seed drill to travel100mm. 6 Test procedure The programming of the mandatory tes
