GB/T 24675.1-2024Conservation tillage equipment - Part 1: Shallow cultivator (English PDF)

3 Terms and definitions

3.1 shallow scarification: soil loosening carried out no deeper than the plough pan, in which the soil layers stay largely undisturbed. 3.2 shallow cultivator: an implement whose loosening depth does not exceed the plough pan. 3.3 plough pan: the compacted soil layer below the tilled layer.

3.4 shallow loosening depth: the vertical distance from the bottom of the loosened furrow to the ground surface at that point before the operation, expressed in centimetres.

3.5 remote monitoring system for shallow scarification: a system that monitors the work of the shallow cultivator automatically and processes the monitored data in real time. 3.6 operation area: the product of the distance travelled by the unit while at work and its working width.

4 Product designation

The type designation is written according to JB/T 8574. It opens with the classification code 1 for tillage and land preparation machinery, followed by the category code QS for shallow scarification, then the first feature code, X for the mounted form and nothing for the trailed form, then the second feature code, the number of folding sections written 1, 2, 3 and so on; after the dash come the main parameter, the working width in centimetres, and the improvement code, written A, B, C and so on.

The worked example given in the clause is 1QSX3-900B, read as a mounted shallow cultivator of the second improvement, with three folding sections and a working width of 900 cm.

5 Technical requirements

5.1.1 to 5.1.3 Guarding follows GB 10395.1 and the safe distances that keep the upper and lower limbs out of the danger zones follow Clause 4 of GB/T 23821-2022. Where a working part stands higher than 4 m in any operating or transport position, or when folded or opened, a safety sign and a warning about entanglement with overhead power lines are provided at a conspicuous place on the machine, and the manual warns of the danger of contact with such lines. Where rotating or folding parts are power driven, a stable control device is provided outside the rotating or folding zone. A locking device holds folded or rotated parts in the transport state, using a mechanical device, a hydraulic device or gravity self locking; where the hydraulic lock is not mounted directly on the cylinder, the hoses and pipes between cylinder and valve have a burst pressure of at least four times the rated working pressure of the system. The mechanical lock withstands the force produced by the folding or rotating control, and unlocking and opening are governed by separate operations.

5.1.4 to 5.1.6 Every machine carries safety signs conforming to GB 10396: a sign warning of crushing and shearing, for instance near the hitch lifting system and when the machine is raised or lowered; on wide folding machines, a sign near the folding device warning of crushing and shearing and calling for the locking device to be engaged when the machine is folded; and a sign forbidding anyone to stand within the folding radius. Machines wider than 2.1 m carry rear marking reflectors or contour strips of reflective material. The manual gives the safety precautions for operation and maintenance and is written according to GB/T 9480.

5.2.1 On level test ground with soil moisture of 15 percent to 25 percent, soil firmness not above 2.0 MPa and stubble no higher than 20 cm, and at a depth not exceeding the plough pan, Table 1 requires a clod-breaking rate of at least 85 percent for clods no larger than 4 cm, a loosening depth set by local agronomic practice, depth stability of at least 80 percent, a weed-cutting rate of at least 90 percent, a surface levelness of 3.0 cm or better, a soil looseness of at least 15 percent, a wheel slip of the unit no greater than 15 percent and an operational reliability, expressed as availability, of at least 95 percent.

5.2.2 Table 2 sets the indicators of the remote monitoring system: depth measurement error no greater than 1 cm, area measurement error no greater than 3 percent, position data sampling interval no longer than 2 s, working speed measurement error no greater than 1 percent, and interval between data uploads by the terminal no longer than 10 s.

5.3 The machine is built to drawings and technical documents approved under the prescribed procedure; all parts are inspected, and bought-in and subcontracted parts carry inspection certificates before assembly; machined and pressed parts are smooth and flat, free of burrs and flash, and free of cracks and marked wrinkles; castings and forgings are free of blowholes, inclusions, shrinkage porosity and sand holes; welded assemblies are sound, with flat, clean welds free of missed welds, oxidation and burn marks; and the main dimensions and connection points of the hitch follow GB/T 20088. A remote monitoring system is recommended on the unit; where fitted it locates the machine accurately, measures working parameters such as depth, working speed, working time, cumulative area and real time position, takes photographs and transmits the data to a server in real time, and stores the monitored data for later query when the network connection fails.

5.4 The share is made of steel of mechanical properties not below the 35MnB of 6.4 of GB/T 3077-2015 and the shank of steel not below the 45 steel of GB/T 699; the share is heat treated to 40 HRC to 45 HRC and the shank quenched and tempered to 26 HRC to 30 HRC. The vertical or transverse teeth of the clod-breaking press roller are evenly distributed and of the height called for by the design. The hydraulic system and its components follow GB/T 3766, the controls being light, flexible and reliable and free of sticking; hydraulic components and fittings are arranged or protected so that a burst does not spray fluid straight at the operating position; the marked maximum working pressure of the hoses is not below the normal working pressure of the system; and the pipework is secured so that it cannot be twisted, flattened or damaged.

5.5 After assembly the vertical difference between the share points and the underside of the beam is not more than 8 mm. Bolts and screws in the main beam, the bearing seats and the hitch are of property class not below 8.8 of Clause 7 of GB/T 3098.1-2010 and nuts not below class 8 of Clause 7 of GB/T 3098.2-2015, with reliable locking; Table 3 gives the tightening torque in newton metres for each nominal thread size, from a minimum and a maximum of 22 and 29 at 8 mm, 44 and 58 at 10 mm, 76 and 102 at 12 mm, 121 and 162 at 14 mm, 189 and 252 at 16 mm, 260 and 347 at 18 mm, to 369 and 492 at 20 mm. The depth and other adjusting mechanisms work easily, flexibly and reliably, rotating parts turn freely without sticking or knocking, and the lubrication points are filled.

5.5.5 and 5.5.6 On wide folding machines the folding mechanism folds and unfolds smoothly and without sticking, the two sides move in step where they fold and unfold together, and the hydraulic system neither seeps nor leaks; the folded sections are straight and neat when opened and have a locking mechanism; and in the transport state the folding parts are locked or fixed so that they cannot open of themselves in transit. The transport clearance is at least 110 mm for trailed machines and at least 300 mm for mounted machines.

5.6 Rust, oil, weld spatter and dirt are cleaned off before painting. Soil-engaging parts such as the shares may be left without primer and given black top coat only. The painted frame is even in colour, flat and smooth and shows no bare patches, and the machine as a whole is clean and free of rust and knocks. Painting follows JB/T 5673, with the ordinary weather resistant coating TQ-2-2-DM.

6 Test methods

6.1 The test ground is level and carries no more than 1 kg of vegetation, stubble included, per square metre, with stubble no higher than 20 cm, soil moisture of 15 percent to 25 percent and soil firmness not above 2.0 MPa. The measured section is at least 50 m long with run-in and run-out sections of at least 10 m at each end, and its width is at least ten times the working width. Absolute soil moisture, soil firmness and the state of the vegetation are measured according to GB/T 5262. The test machine and its tractor are in good technical condition and are adjusted and serviced as the manual requires, the tractor is not changed at will during the test, the operators are trained and certified, and the working speed of the unit follows the manual. The instruments and equipment used are calibrated and within their period of validity.

6.2.1.1 Depth is measured at the maximum, the minimum and the rated working speed given in the manual, working at full width; each forward speed is one test condition, each condition is run out and back, and three conditions are tested. Five points are taken on the diagonal of the measured section, the number of shares measured depending on the actual work, using a depth gauge or another instrument. On flat land the depth is the vertical distance from the furrow bottom to the surface before the operation; on ridged land it is the difference between the distance from the furrow bottom to a horizontal datum after the operation and the distance from the surface before the operation to that same datum. The mean depth, the standard deviation, the coefficient of variation and the stability coefficient are computed for each run by Formulae (1) to (4) and for each condition by Formulae (5) to (8).

6.2.1.2 to 6.2.1.4 The working width is measured at the points where depth was measured and averaged. The weed-cutting rate is measured at five points on the diagonal of the measured section, over an area of 1.0 m by 1.0 m at each point, by counting the weeds present before the operation and those left uncut after it and applying Formula (9), the mean of the points being the result. The clod-breaking rate is measured at one point in each of two runs out and back, sampling along the direction of tillage over an area of 0.5 m by 0.5 m, by weighing the clods of the whole loosened layer whose longest edge is no greater than 4 cm and the total mass of clods, applying Formula (10) and taking the mean.

6.2.1.5 and 6.2.1.6 Soil looseness is measured at one point in each of two runs: before and after the operation a soil profile meter traces the surface line before the operation, the surface line after it and the furrow bottom line, at the same position perpendicular to the direction of travel, and Formula (11) relates the rise of the surface to the depth of the furrow bottom below the original surface. Surface levelness is measured at the same time. After the operation a horizontal datum line above the highest point of the surface and as wide as the working width is set perpendicular to the direction of travel and divided at 20 cm intervals over at least 2 m; the distance from the datum to the worked surface is measured at each point, a laser non-contact profilometer being allowed, and the mean and the standard deviation are computed by Formulae (12) and (13). Three measurements are made and the mean of the three standard deviations is the levelness after the operation.

6.2.1.7 and 6.2.2 Wheel slip is found by measuring the distance travelled by the rear driving wheels or tracks of the tractor for the same number of revolutions when running free and when working, and applying Formula (14). For the remote monitoring system, the depth measurement error is the absolute difference between the mean depth of the condition and the depth reported by the terminal, Formula (15), the test running alongside 6.2.1.1, made at least three times and averaged. The area measurement error is found on a regular rectangular plot of at least 2 000 square metres, worked repeatedly in straight passes with neither overlap nor missed strips, by comparing the area computed by the system with the measured worked area through Formula (16), three times and averaged. The speed measurement error is found while the unit works at rated speed, by comparing a conventional speed measurement with the value monitored by the system.

6.3 The hardness of the heat treated share is measured according to GB/T 230.1. General requirements are checked by eye and by conventional measurement, the main dimensions and connection points of the hitch according to GB/T 20088. The installation height difference of the shares is the difference between the greatest and the smallest height from a share point to the underside of the beam, measured on a platform or on level ground, and the transport clearance is the distance from the lowest point to the ground with the machine set in the transport position. A wide folding machine is opened and folded ten times unladen after assembly and checked item by item against 5.5.5 for the tightness of the hydraulic system and the correct travel of the working parts. The hydraulic system and its components are checked against GB/T 3766 by eye, by feel and with conventional gauges. Paint quality is judged by eye, the film thickness with a paint thickness gauge and the adhesion according to JB/T 9832.2.

6.4 At least two machines go into the production test before series production, with tractors suited to the test and the necessary spares and tools. Reliability is assessed by the fixed time censoring method, each machine working 120 h in total, with the working, failure and repair record kept for each machine and the operational reliability computed according to GB/T 5667. A failure is the loss of a required function or a performance outside the acceptance range under the stated conditions, judged according to GB/T 5667; failures bound up with intrinsic failure of the machine, such as those that endanger safety, cause loss of function or damage parts, are counted, while those that merely inconvenience the operator and can be cleared easily with the tools carried on the machine are not. Failures caused by use outside the range stated in the manual and the technical conditions, by wrong use, servicing or operation, or by chance external events, are not counted. If a major or critical failure occurs during the production test, the test is stopped at once and reliability is judged as failed.

7 Inspection rules

7.1 Every machine leaving the works has been inspected and passed by the inspection department of the maker and carries a certificate of inspection; the delivery inspection items are those marked in Table 4.

7.2 Type inspection is carried out on trial type approval of a new product or of an old product transferred to another works; after regular production has started, where the structure, the process or the materials change enough to affect performance; periodically in normal production, generally once every three years or after a certain accumulated output; and when production resumes after a long stoppage. The type inspection items are those marked in Table 4.

7.3 Sampling follows the single sampling plan of GB/T 2828.1, two machines being drawn at random from the qualified products of the past year, with a sample of not less than twenty units; sampling at a user or at a sales outlet is not bound by this. The document states both the figure of two machines drawn and the figure of not less than twenty units.

7.4 Items are classed as class A, class B and class C nonconformities according to their effect on product quality, the classification being given in Table 4, and the sampling decision follows Table 5, in which AQL is the acceptance quality limit, Ac the acceptance number and Re the rejection number. Table 5 works at inspection level S-1 with sample size code letter A and covers three class A items at AQL 6.5, acceptance number 0 and rejection number 1; thirteen class B items at AQL 25, acceptance number 1 and rejection number 2; and twelve class C items at AQL 40, acceptance number 2 and rejection number 3. Every item is assessed and the decision made class by class: the product passes where the number of nonconforming items is not greater than the acceptance number, and fails otherwise. Where the purchaser samples the product, the contract or the agreement may be followed instead.

Table 4 places in class A the safety requirements of 5.1, checked at delivery and at type inspection, and operational reliability and clod-breaking rate, checked at type inspection only. Class B holds the loosening depth and its stability, the weed-cutting rate, surface levelness, soil looseness and the three monitoring system errors, all at type inspection only, together with the general requirements of 5.3.2 to 5.3.6, the share and shank, the clod-breaking press roller, the hydraulic system and the depth and other adjusting mechanisms, all checked at both stages. Class C holds wheel slip and the remote monitoring system of 5.3.7 to 5.3.9 and the two monitoring intervals, at type inspection only, together with the installation height difference of the shares, the tightness of the main fasteners, the folding mechanism of wide folding machines, the transport clearance, the paint and appearance quality, the film thickness and adhesion, the manual and the nameplate, all checked at both stages.

8 Marking, packaging, transport and storage

8.1 Every machine carries a nameplate fixed in a conspicuous position and conforming to GB/T 13306, giving the type and name of the product; the main technical parameters, such as overall dimensions, matching power, working width, number of shares and loosening depth; the trademark; the works number; the date of manufacture; the name and address of the maker; and the number of this document.

8.2 and 8.3 The technical documents travel in a waterproof bag and comprise the certificate of inspection, the operation and maintenance manual, the packing list for the complete product and the after-sales service voucher. The packing of each machine is such that no knocks occur in normal transport.

8.4 and 8.5 Dispatch from the works complies with the rules of the transport authorities, so that no part is damaged under normal transport conditions. The machine is stored in a dry and ventilated place, with protection from rain where it is kept in the open.