A. P. Larin

Determining the dimensions of mixing mill rollers

ConclusionsIn developing designs of refractory-producing mills, one must try to achieve the smallest roller diameter and roller weight corresponding to the specified pressure and width of the roller on the mixture. An equation is given for determining the optimum diameter and weight of the rollers.

Choosing mixers for body preparation with caustic dust

ConclusionsWe determined the optimum process parameters for preparing bodies from caustic dust for which a high output mixer is recommended.It is necessary to solve the problem of the regular production of mixer runnermills of continuous action designed by the Urals Machine Factory, with the production in the near future of a prototype for industrial testing.

Determining pressing rates for refractory semidry bodies

ConclusionsAn inverse relationship was established for the permitted pressing rate and the ratio between the volume of the products and its double perimeter in plan. With an increase in the dimensions of the article it is necessary to reduce the pressing rate to exclude the formation of pressing cracks.Empirical equations are proposed which as a first approximation can be used for calculating the average rates and durations of pressing, and also for accumulating data connected with the question under discussion.

Performance of mixers at the Chasov Yar Refractories Combine

ConclusionsDuring the blending of bodies, containing a mixture of chamotte and clay ground in combination in tube mills, on mixers of four types used at the Chasov Yar Combine, the best pressed specimens were obtained when the bodies were worked on the centrifugal runnermills 115 M with normal rollers. Therefore, we do not recommend the removal from these mixers of factory-made rollers, although the mixers require improvement.The dispersed feeding of slip into the mixer reduces the quantity of coarse granules in the prepared bodies. In this case it is necessary to use replaceable tubes for periodic cleansing of the apertures or to ensure forced delivery of the slip with spattering across the surface of the body being mixed.

Industrial development of vibroimpact molding of silicon carbide refractories

ConclusionsA technology was developed for the vibrocompaction of silicon carbide refractories. The efficiency of the process was confirmed in industrial conditions.The properties achieved by vibrocompaction in silicon carbide refractories and their uniformity of distribution appreciably exceeds similar characteristics for tamped, and to some extent pressed, refractories.Vibromolding equipment is very simple in design, of low metal content, low power rating and cost, and can be used to obtain product qualities at pressures of 1–2 kg/cm2 that are achieved in pressing only by pressures of about 1500 kg/cm2.The use of vibrocompacted silicon carbide slabs in the porcelain industry as kiln furniture increased the inter-repair periods for shelf cars for firing pottery.

Experience with producing ladle and blast furnace brick with a change in pressing rates

ConclusionsA reduction in the pressing rate improves the factors of ladle and blast furnace refractories, since it affords the possibility of increasing the permissible upper limit for the pressing force, starting from the condition that there are no overpressing cracks.In order to obtain refractories with a low porosity it is desirable to prepare ladle and blast furnace brick with 5.0–5.5 pressings per minute with an average pressing rate of 9–11 mm/sec.

Preparing tar-dolomite bodies in the SMB-2000-PNM mixer

ConclusionsThe SMB-2000-PNM mixer with steam heating can be used for preparing hot tar-containing bodies.The radial gap between the blades and the reinforcing elements should be maintained at no less than 20 mm, and between face no more than 5 mm.Replaceable reinforcement elements should be made from manganese steel.When planning new models for the mixer it would be desirable to install an extending jack for supporting the lids of the discharge traps, and centralized feed of thick lubricant to the bearings,etc.

Main trends in complex mechanization and automation of refractory production

ConclusionsThe range of problems examined shows that even at the present time the level of machinery makes it possible to carry out complex mechanization and maximum automation of the mass production shops for alumosilicate and magnesium refractories, although it requires a great deal of design work, manufacturing and assimilation of new instruments and machines.When designing new factories and reconstructing existing ones, chamotte firing plants with rotatory kilns, grinding, mixing and furnace units can be fully automated and controlled from dispatch points. The automation of presses can be carried out so that they produce mass articles of simpler design.On the basis of the latest achievements of technics, it is essential to work out as early as possible comtempory machines for refractory production, wear-resistant materials for their parts, centralized manufacture of standardized replacements for machines and mechanisms at specialized plants.