Coke nut

Coke nut is specially marked by coal coke classification on coke production and other chemical enterprises, it is used in ferroalloy, electrodes production, and other industrial branches, as well as for export.

Industrial enterprises are the main users of coke nut. it is marked as: о – nut, к – coke, 1, 2, 3, 4 – grade value. This is an example of coke nut marking by the order and (or) other documentation usage: “coke nut, grain size category 10 – 25 mm, grade ok 1, тu u 19.1-00190443-120:2012”

Technical requirements

Coke nut should correspond to the requirements of these technical conditions.Coke nut depending on the lump grade belongs to two grain size categories – 10–25 mm and 8–25 mm; depending on the ash content – four grades, marked as: ок 1, ок 2, ок 3, ок 4.As for its quality properties, coke nut should correspond to the norms and requirements shown in the table 1.


The norm for the class and grade

Test method

10-25 мм

8-25 мм

ОК 1

ОК 2

ОК 3

ОК 4

 Ash content, ( Аd), %, no more than





Acc. to GOST 11022

Total moisture content percentage ( Wr t ), %, no more than





Acc. to DTSU ISO 579 or GOST 27588

weight percentage of lumps %, no more than:


As for GOST 5954.2

bigger than 25 mm





smaller than 10 mm





smaller than 8 mm





Total moisture content is no rejection sign and serves to recalculate into the dry basis the batch of the coke nut that arrived at the customer. The revaluation in the dry basis is conducted according to the annex а sou mpp 75.160-323.

Weight percentage of lumps %, no bigger than 25 mm is no rejection sign either, it is an identification parameter.

It is allowed, under the approval of the customer to deliver the coke nut of grade ok 3 with an ash content and a lump weight percentage of less than 10 mm exceeding 18%.

A property of general sulphur and other additional properties in a coke nut are determined according to the requirements of the customer stated in the delivery contract. Norms of the properties, regularity and methods of determination and test methods are mentioned therein as well. The properties in question are no rejection signs and serve as identification parameters.