• Manufacturing of industrial thermal equipment
  • Own design and production facilities
  • Modern equipment and machines

Mine electric furnace for gas carburizing

Purpose and application

Appointment: carburizing (carburizing) of low-carbon steels is performed to increase the concentration of carbon on the surface of the workpiece. Carburization of steels occurs at elevated temperatures, in a specially prepared, controlled and regulated atmosphere. To ensure optimal conditions for the diffusion of atoms carbon into steel, specialized electric furnaces of the SShTsM models have been developed.

The most widespread are mine designs using a muffle. In electric muffle furnaces, carburizing (hydrocarbon) medium is localized in the volume of a sealed reactor, which has a positive effect on the performance of electric heaters, lining, thermocouples, etc. Shaft muffle furnaces for carburizing are used in conditions of small and medium-scale production.

The source (base) for the carburizing medium can be liquid (kerosene) or gaseous (natural gas, propane-butane) hydrocarbons. The carburizing kilns themselves are designed with the ability to use any of the possible carburizers. By agreement with the Customer, the electric furnace can equipped with a liquid or gaseous carburizer supply system.

Description of construction

Cementation electric furnace

The carburizing kiln consists of heating unit, mine type, in which the gas-tight muffle is installed. The tightness of the working space is ensured by a removable cover, which is suspended on a pivot stand. The furnace is supplied with a control cabinet, an installation for monitoring and regulating furnace atmospheres, a candle, an explosive valve and other peripherals.

Heating up an electric furnace produce heaters which, by agreement, can be in the form spirals or zigzags, heater material fechral or nichrome. Coil heaters are mounted on corundum insulators, which are spaced from the lining and do not touch the thermal insulation. Zig-zag heaters attached with hooks directly to the lining. To equalize the temperature, the heaters are evenly distributed along the height and commutated into independent heating zones.

Grouting muffle The furnace is made in the form of a rolled cylinder, made of steel no worse than 20X23H18 with a hermetically welded bottom. At the top of the cylinder there is support and sealing flange. Inside the muffle, a flow-forming screen is installed to circulate the flow and a grating for the charge in the form of rays coming from the center. The system of flow screen and support forms a circulation channel.

Oven cover intended for thermal and gas limitation of the working space. The cover is lifted and lowered by an electric drive, in in the raised position, it is retracted to the side along the hinge axes of the cantilever frame, freeing the loading opening. The cover consists of a carrier disc, on which a metal is attached, going into the muffle, casing and rack with a fan. The carrier disc presses the cord seals on the muffle flanges. The casing is made in the form of a box, which is clogged with fibrous insulation. A fan stand with a downward-running wheel mixes the gases in the muffle. Through the axis of the lid, into the zone heating, pipes for supplying and removing gases, a container for witness samples are removed. The gas outlet is connected to the candles.

Carburizing and oxidizing agent feed, as well as the analysis of the furnace atmosphere is carried out by the installation of supply, control and regulation of furnace atmospheres, type PKPA-Zh for the case of liquid carburizer or PKPA-G system for gaseous carburizer. The plant consists of two separate units. Dosing unit for initial components to form optimal a cementing medium and a control unit for the concentration of some atmospheric components. The system is controlled by a logic controller with hard-wired control and support functions necessary locks.

Description of gas preparation plants

Installation of PKPA-G. The unit supplies hydrocarbon gas as a carburizing agent and air as an oxidizing agent of the optimum ratio. Forming the right carbon potential is produced by changing the volume of flow rate of hydrocarbon gas or air, depending on the recommended concentration of CO2 gas for the desired carbon potential. Additional control of oxygen concentration is performed. The carburizing atmosphere in the muffle is constantly renewed, regulated and maintained at an optimum value (~0,85-1,1% C).

Installing PKPA-Zh. The unit supplies hydrocarbon liquids (kerosene, triethanolamine) as a carburizer, water and air as an oxidizing agent for optimal volumes. The formation of the required carbon potential is carried out by changing the volume of kerosene consumption or water with air, depending on the recommended concentration of CO2 gas for the desired carbon potential. Additional control is carried out oxygen concentration.

The use of PKPA-G or PKPA-Zh units for the regulation of carburization processes brings the gas concentrations in the muffle to optimal ratios. Increase implied gas circulation in the muffle by 2 or more times, without the risk of soot precipitation, this leads to an acceleration of the carburization process with an improvement in the layer structure. Monitoring and regulation minimizes microstructure defects, including cementite mesh. The absence of soot formation increases the service life of the furnace elements by 4-5 times.

Control system carburizing furnaces are installed in the control cabinet. The PKPA installation is integrated with the electric furnace control system. The cabinet is equipped with a temperature control device, registration of the heating schedule, "Termodat" brands, digital current indicators, thyristor systems with pulse width modulation function. Also on the control cabinet are the oven control buttons, toggle switch, status indicator lamps and alarm. The system provides the necessary technological modes, the necessary interlocks of emergency situations are implemented.

All electric carburizing furnaces are manufactured with heating temperatures up to 950 ° C. The letter "Г" or "Ж" can be added to the equipment designation, this will be designate the completing of an electric furnace with a gas carburizer feed unit (G) or a liquid carburizer (G).

Main technical characteristics of electric carburizing furnaces

Designation Working dimensions (d × h), mm. Dimensions (A × B × H), mm power, kWt Furnace weight, kg Average production, kg / hour
СШЦМ 4,5.6/9,5 450×600 1460×1510×2200 45 1000 120
СШЦМ 6.9/9,5 600×900 1600×1770×2350 50 1240 200
СШЦМ 6.12/9,5 600×12001620×1700×2700 75 1650 250
СШЦМ 8.13/9,5800×1300 1900×1900×300090 2350 400
СШЦМ 8.18/9,5800×1800 1900×1900×3550112 3700 600
СШЦМ 10.15/9,5 1000×15002200×3500×380015042001000
  • overall dimensions are indicated without PKPA installation.
  • Average productivity is based on 1mm carburizing depth and temperature 920°C.

Scroll to view the table
Furnace drawing SShTsM

Mine electric furnaces take up less floor space. The working space is made in the form of a metal muffle, which excludes the interaction of the atmosphere and heaters. The intensive circulation of the furnace atmosphere equalizes the temperature and composition of the gas over the volume of the charge. The electric furnace is lined, undergoes factory tests, with adjustments to the required performance indicators. We offer a wide range of cementing electric furnaces for various tasks with an optimal set of functions and capabilities, including those not reflected in this section.

We will answer your questions Leave a message
620085, Yekaterinburg, st. Monterskaya, 3, workshop 11
(the territory of OJSC "Ural plant RTI")
+7 (343) 221-53-39 – Consultant
+7 (343) 221-53-55 – bookkeeping
Время работы
Working hours
Mon-Fri from 8.00-17.00