Evaluation Report No.
BELARUS NIVA SK-5 SELF-PROPELLED COMBINE MANUFACTURER: Tractoroexport Rostselmash Rostov-on-Don, U.S.S.R. RETAIL PRICE: $27,926.24 (July, 1977, f.o.b. Regina with 4420 mm (14.5 ft) table, 3200 mm (126 in) Melroe pickup, grain loss monitor, automatic feed control, six-bat pickup reel, cutter bar, metric tools and spare parts kit. DISTRIBUTOR: Belarus Equipment of Canada Ltd. 1739 Victoria East Regina, Saskatchewan S4P 0P9 FIGURE 1. Schematic View of the Belarus Niva SK-5.
including a parts list, they were very wordy and difficult to understand and did not include some necessary information. A considerable number of minor but aggravating durability problems occurred and several field modifications had to be performed resulting in many hours of down time. Most problems stemmed from improper pre-delivery by the local distributor.
damaged O-ring in the piston. 25. The stone trap will be modified on new model Niva SK-5. 26. The straw buncher feed finger assembly will be removed from combines sold in Western Canada and replaced with a deflector shield over the rear axle. In addition, instructions on removal of sieves will be more explicit. 27. The inboard bearing on the cross auger has been replaced with a sealed bearing.
height, pickup or reel speed, radiator chaff deflector and grain tank vibrator were located in a cluster to the right of the operator. Arrangement of these controls was confusing, the controls were quite irresponsive and the mechanical linkages wore rapidly during use. The header lift was slow, especially with warm hydraulic fluid, often necessitating stopping when crossing gullies or washouts, to prevent the header from striking the ground. set the feed control at the desired feedrate.
had to be turned off whenever the engine was not running to prevent battery discharge. The electrical system circuit breaker was also inconveniently located inside the battery box. FIGURE 6. Schematic Illustration of Manoeuvring Required to Pick a Windrow Around a 90° Corner. FIGURE 7. Instrument Console on Niva SK-5. The speedometer was driven from the transmission input shaft and had a scale for each gear. Its operation was erratic and intermittent throughout the test.
Plugging: The table auger and feeder were very aggressive. When properly adjusted, table auger plugging seldom occurred, even in damp crops. Occasional plugging of the table auger occurred in tough bunchy Midas rapeseed and in damp heavy windrows of Bonanza and Betzes barley. Table auger unplugging was made easy by using the supplied bar and rocking hub on the upper feeder shaft. The feeder conveyor never plugged during the test. The cylinder was very aggressive and positive.
clearances were 42 mm (1.65 in) rear, 46 mm (1.81 in) centre and 48 mm (1.89 in) front. Suitable concave settings were 4 mm (0.16 in) rear, 16 mm (0.63 in) centre and 20 mm (0.79 in) front in dry wheat. In rapeseed suitable settings were 22 mm (0.87 in) rear, 33 mm (1.30 in) centre and 36 mm (1.42 in) front. FIGURE 10. Concave on the Niva SK-5. Filler bars were not required in any crop. When properly adjusted, average dockage from bolls, white caps, and chaff was about 0.5% in wheat and 0.75% in flax.
Adjusting the Loss Monitor: The loss monitor was adjusted with a knob on the control box in the operator’s cab. To set the monitor, the combine was operated at the maximum speed which gave negligible losses and the knob adjusted until the loss needle read zero. It was necessary to inspect losses on the ground behind the combine to determine the zero loss setting. The loss monitor had to be readjusted for every field.
TABLE 4. Capacity of the Niva SK-5 at a Total Grain Loss of 3% of Yield* Crop Conditions Width of Cut Crop Yield Crop Variety m ft t/ha bu/ac Straw Condition Wheat Wheat Barley Flax Neepawa Neepawa Bonanza Linott 5.5 5.5 7.3 4.6 18 18 24 15 2.76 2.72 3.48 1.44 41 40 65 23 dry to tough dry dry to tough very dry Capacity Results Grain Moist.ure % MOG/ G 14.7 12.0 14.6 8.7 1.31 1.52 0.96 1.47 MOG Feedrate Grain Feedrate Ground Speed t/h lb/min t/h bu/h km/h mph Loss Curve 8.95 9.
use was emphasized in the operator’s manual. The header lock must be used when working beneath the header, such as when cleaning the stone trap. FIGURE 19. Total Grain Losses for the Niva SK-5 and the PAMI Reference Combine in Linott Flax. The ladder for cab and engine access was safe, convenient and equipped with adequate railings. Care must be taken when servicing the engine, to avoid slipping and falling from the combine.
DISCUSSION OF MECHANICAL PROBLEMS VARIABLE SPEED TRACTION DRIVE The variable speed traction drive performed well, however, during initial adjustment (needed due to belt stretching), the pivot clevis (FIGURE 21) bent when following adjusting procedures outlined in the operator’s manual. To maintain belt alignment during adjustment it was necessary to wedge the left side of the inner adjusting clevis to prevent clevis deformation from the belt load.
APPENDIX I SPECIFICATIONS MAKE: MODEL: SERIAL NUMBER: MANUFACTURER: WINDROW PICKUP: -- make and model -- serial number -- type -- pickup width -- number of belts -- teeth per belt -- type of teeth -- number of rollers -- apron -- draper -- height control -- speed control (combine) -- apron speed range -- draper speed range HEADER: -- type -- width -- auger diameter -- feeder conveyor -- conveyor speed -- range of pickup height -- number of lift cylinders -- raising time -- lowering time FEEDER BEATER: --
APPENDIX II STATISTICAL SIGNIFICANCE OF CAPACITY RESULTS The following data are presented to illustrate the statistical significance of the capacity results shown in FIGURES 13 to 16. This information is intended for use by those who may wish to check results in greater detail. Sufficient information is presented to permit calculation of confidence belts.
