BRIEF COMMUNICATIONS AND LETTERS TO THE EDITOR

M O D E R N I Z A T I O N OF 1 0 0 - T O N C A R W E I G H B R I D G E S

N. Y a . K o l e s n i k o v a n d N. S. C h e r n i e n k o UDG 681.264.001.6

It is known that the Ministry of Transport has developed, and the Commit tee of Standards, Measures and Mea- suring Instruments of the Council of Ministers of the USSR has approved, a plan for modernizing 100-ran car weigh- bridges by extending their weighing platform. Weighbridges which had been modernized according to this plan were demonstrated in 1965 at the Moscow railroad to the participants of a conference on the modernizat ion of scales organized by the Commit tee of Standards and the Ministry of Transport.

The Armavir Measuring-Instrument Plant manufactures the required units and components for modernizing the weighbridges according to the above plan, However, it was found in practice that certain administrations in- cluding the Ministry of the Mine Industry modernize only the weighbridges which are not located under loading hoppers. However, weighbridges are located under hoppers in prac t ica l ly a l l the pits, and their modernizat ion is

im possible without reconstructing the loading devices, since the hopper supports are placed too closely to each other. Moreover, their modernizat ion entails the production of new devices and the constructions of an addit ional railroad stretch for loading coal into the cars from the hopper when the weighbridge is closed.

Bearing in mind the above considerations, two trusts of the Donetskugol' combine have equipped a 100-ton

car weighbridge with a device for connecting its lef t -hand platform separately, thus making it possible to weigh six- axle open cars in the course of their loading bogey by bogey on the left and r ight-hand platforms of the weighbridge. Moreover, in pits which are not provided with double-sided hoists, t ract ive force has become avai lable , and it was no longer necessary to maneuver the roiling stock on the weighbridge in the course of loading.

The Donets laboratory for state supervision of standards and measuring equipment has carried out comparat ive check weighing of s ix -ax le cars by means of the above method and in a single operation on a 150-ton weighbridge. The two coal trusts borrowed for these exper imenta l weighings 20 s ix-axle open cars whose to ta l gross weight amounted to 2457.6 tons. The discrepancy between the two types of weighing amounted to • ~0.31% in the Sovetskugol ' and the Proletarskugol ' trusts respect ively, and the largest difference in the weights of separate open cars amounted to • and •176 in the same trusts respect ively. The precision norm in weighing coal specif ied by GOST (All-Union State Standard) 11762-66 lies in the range of • 1% Thus, the suggested method of weighing s ix -ax le open cars in turn on the left and r ight-hand platforms of weighbridges frees t ract ive force for maneuvering

the rolling stock in the course of loading and weighing, and meets the requirements of GOST 11262-66 with respect

to the precision norms in weighing coal.

If it is taken into consideration that the cost of modernizing weighbridges amounts to 5,000-7,000 roubles, and that of auxil iary devices and structures amounts to as much and in certain instances even more, then it wil l be seen that in the Donets region alone the modernizat ion of car weighbridges of the coal industry wil l cost the state about 1 mi l l ion roubles. However, their equipment with the device for connecting the le f t -hand platform of weigh-

bridges will cost at the most 4,000 roubles.

It should also be noted that the continuous rise in the weight-carrying capaci ty of our car stock and the in-

creasing circulat ion of the e igh t -ax le open cars, whose extreme axle base is longer than the length of modernized weighbridges, makes them again unsuitable for weighing open cars in a single operation.

Thus, the modernizat ion of ear weighbridges by the method of extending their platform is disadvantageous for the pits, not only economica l ly , but also with respect to their future use.

We corfsider that weighbridges which are intended for weighing loads whose weighing precision is specified within • including pit weighbridges which are located under loading hoppers, should not be modernized by ex- tending their platforms. It is more pract ical to equip their lef t -hand platform with a switching system and toweigh six and e igh t -ax le open cars in two operations, by weighing their bogeys in turn,, in the direction of the train move- ment, on the left and r ight-hand platforms of the weighbridge.

Translated from Izmer i t e l ' naya Tekhnika, No. 5, p. 98, May, 1968. Original ar t ic le submitted August 10,

1967.

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