ANTAL INDUSTRIAL AND SALES LLP 50 YEARS IN THE WORLD OF INDUSTRIAL FURNACES
Low Temperature Drying Tunnel Oven

Features

Heating Method:
Power:
Chamber Dimensions (m):
Max. Operating Temperature:
Batch Weight:
Thermal Insulation:
Controls:
Data Logging:
Application:
natural gas firing, direct
3500 kW
4m x 3m x 100m
150 °C
continuous mechanical feeding
Rockwool, 160 kg/m3
PLC, PC, Ethernet, Internet access
continuous data logging on PC
drying of coloured resin coating on steel sheets


Description

This is a directly heated tunnel oven that is designed for continuous operation and with a conveyor to move products through the 12 heating zones. Each zone has a powerful fan to ensure a high airflow and good temperature accuracy. The fans blow hot air through an appropriately dimensioned blow wall onto the products. Fresh air is supplied through motorised louvres. The louvre position is continuously controlled with the current positions being displayed in percentage on the control panel. Louvres can be adjusted from a touchscreen panel only by the shift leader as well as the operator in charge of the equipment with a dedicated password access. Without a password being entered successfully, the equipment parameters, including the heating zone temperatures, exhaust louvre positions and other process parameters, cannot be changed.

Applications

Used to receive and dry products or materials that are applied to those products that are continuously coming from a production line.

Buying Criteria

Drying temperature and heat demand, temperature accuracy requirement and other process parameters (heating-up time, airflow requirement, etc.)

Aluminium Smelting Furnace

Description

Aluminium smelting furnaces are normally indirectly heated, electric resistance heated or natural gas fired crucible furnaces. The melting point of aluminium is 660.32°C, such furnaces are, therefore, designed to have a maximum operating temperature of 900°C. Furnace designs may be dynamic, tilting or stationary/top-loading.

Applications

Aluminium smelting furnaces are normally used by mass goods manufacturers and raw material producers.

Buying Criteria

Selection should be based on the size of batches to be melted in one go as well as the intensity of the use of the melt. The volumetric capacity, output, design and number of furnaces should be defined accordingly.

Push-Through Oven

Description

This is a directly or indirectly heated oven that is designed for continuous operation. Products to be heat-treated are mechanically pushed through the oven. When a heat-treated batch is unloaded at the oven discharge, a new batch enters the oven chamber, and then the line moves one batch forward. Charge batches move on the fire-resistant bottom rails of the oven. Batch units should be rectangular in shape (being either rectangular workpieces or rectangular baskets for smaller products). Heat-treated products are discharged through an opening in the faceplate, a hole in the bottom or through the oven side panel by using a transversal pusher. Fans are installed in the oven top, and radiant tubes on the side panels. To ensure uniform heat distribution, the oven can be fitted with a muffle. Push-Through ovens are the simplest heat treating units designed for continuous mass production and do not require any handling mechanism to be installed inside the oven chamber.

Applications

Annealing and continuous carburisation of mass produced products

Buying Criteria

Process objective, heat treating temperature and temperature accuracy, the time/temperature curve of the heat treating process, dimensions and weight of products, method of loading and unloading the products, the equipment required for loading and unloading, protective atmosphere requirements, heat treatment capacity requirement (kg/h), oven operating hours, heating method requirements (gas or electrical), etc.

Tunnel Oven for Annealing Bearing Rings

Features

Heating Method:
Chamber Dimensions (mm):
Max. Operating Temperature:
Thermal Insulation:
Controls:
Data Logging:
Heat Treatment Process:
Electric resistance heating
800 x 800 x 25.000
950 °C
ceramic fibres combined with fireclay lining
PLC, industrial PC, with an automatic cycle
Industrial computer with comprehensive data logging
annealing bearing rings after forging


Description

This is a directly heated tunnel oven that is designed for continuous operation and cars (i.e. a car bottom) of a high load capacity to move the charge through 5 heating zones. Each zone has a fan to ensure improved heat transfer. The batches of products are put in baskets to be placed on the cars. The cars are then gradually moved through the different temperature zones from the inlet to the outlet of the oven.

Applications

Stress-relief annealing of mass-produced parts, machine components and structures made of alloyed and non-alloyed steel

Buying Criteria

Dimensions and weight of products, annealing temperature, temperature accuracy requirement, other process parameters (heating-up and cooling times, etc.)

Notes

The two ovens had to be designed, manufactured and installed in lieu of the client’s old ovens, while the existing rails and carriages had to remain in place and be renewed with the same functionality.

Rotary Drum Heat Treatment Line with a Protective Atmosphere and Indirect Heating for Hardening Balls and Rollers

Features

Heating Method:
Max. Operating Temperature:
Tempering Furnace:
Thermal Insulation:
Controls:
Data Logging::
Heat Treatment Process:
Electric resistance heating
Hardening furnace: 950 °C
700 °C
ceramic fibres
automatic, PLC, PC, thyristor power control
computerised, with continuous documentation
hardening and tempering of bearing balls and rollers


Description

Components of the continuous operation heat treatment line:
  • weigher and feeder
  • rotary retort hardening furnace with a protective atmosphere
  • oil hardening vat (heatable and coolable)
  • washing unit
  • rotary retort tempering furnace
  • discharge unit

Applications

The hardening and tempering of balls and rollers of rolling-contact bearings. Particularly suitable for heat-treating small-size mass produced parts (case hardening (carburising), temper-hardening). The atmosphere that is used for protection is endogas (a gas atmosphere that prevents oxidation and decarbonisation). With an appropriate protective atmosphere, in-line carburisation is also possible.

Buying Criteria

The dimensions, weight and quantity of parts and target parameters of the heat treatment process


Notes

The system was purchased second-hand and shipped flame-cut from the US (without any documents or empty electrical cabinets). The difference between the European and US (3 × 270 V, 60 Hz) power supply systems meant that the 460 kW power system needed a major conversion. The entire control system was upgraded and integrated with all the line units.
The gas supply system underwent a major modification.
A new external cooling unit was designed and manufactured.

Rotary Drum Furnace with Indirect Heating

Features

Heating Method:
Voltage:
Power:
Chamber Dimensions (m):
Max. Operating Temperature:
Thermal Insulation:
Controls:

Heat Treatment Process:

electrical resistance heating
3 x 400 V, 50 Hz
200 kW
Ø 800 x 13.000
750 °C
ceramic fibres
fully automatic, PLC and PC, thyristor power control
continuous data logging on PC
in-process heat treatment of silicon-carbide powder


Description

The furnace chamber is a rotating drum made of refractory steel and is inclined towards the discharge end. The drum revolves inside a thermally insulated chamber fitted with electrical heaters to produce heat energy. Heating is indirect because it is the external surface of the refractory steel drum that is heated directly and the heat is transferred by conduction to the charge in the furnace.

Applications

Raw material processing







Rotary Hearth Furnace (Carousel Furnace)

Features

Heating Method:
Power:
Chamber Dimensions (m):
Max. Operating Temperature:
Temperature Accuracy in the Oven Chamber:
Thermal Insulation:
Controls::
Data Logging:
Application:
electrical resistance heating
2 x 90 kW
Ø2500 x 500 (maximum charge size: Ø 600 x 300)
1000 °C

±5 °C
corundum bottom/ceramic fibre insulation
Schneider PLC
JUMO recorder
heating of parts under N2 atmosphere prior to pressing and establishing a carbon level to prevent decarbonisation by adding methanol


Description

This is a directly heated annealing or heat treatment furnace that is designed for continuous operation and with an annular or plate bottom. The charge is placed on, and moves with, the bottom through the furnace chamber, while the required core temperature is achieved. It is also available in a gas fired design. Depending on the weight of each batch, the charge is put in and taken out by a mechanical manipulator or by hand through a special door in the front panel of the furnace. The furnace can be operated under a protective atmosphere. In such a case, the door has to be fitted with a flame curtain. It is easy to operate, in turn requiring a medium amount of manpower, or none if a mechanical manipulator is used. The operating costs depend on the type of protective gas used.

Applications

Heat treatment of mass produced components

Buying Criteria

The dimensions, weight and quantity of the parts and target parameters of the heat treatment process

Notes:

Process objective, heat treating temperature and temperature accuracy, a time/temperature curve of the heat treating process, dimensions and weight of products, method of loading and unloading, the equipment required for loading and unloading, protective atmosphere requirements, heat treatment capacity requirement (kg/h), oven operating hours, heating method requirements (gas or electrical), etc.

Roller Conveyor Oven

Description

This is an indirectly heated (usually by radiant tubes or, less commonly, by electricity), high-output tunnel oven that is designed for continuous operation and fitted with a roller conveyor to move charges through the various temperature (heating, holding and cooling) zones in line. It is equally suitable for heat-treating large-size products (e.g. rolled round or rectangular bars from steel mills) or smaller products on trays (wire coils, strip coils and shaped pieces) or small shaped pieces in baskets (e.g. bearing rings).

Applications

Suitable where products are handled in batches or stacks in continuous production. A roller conveyor oven is particularly practical where heat treatment needs to be fitted as one of a series of different processes in a production line. Although similar to a push-through oven in terms of capacity and productivity, it has a much more sophisticated mechanical design and, as such, costs more to make and install. Its benefit is that, in contrast with the push-through type, the products from the oven can be directly passed onto an adjacent conveyor system.

Buying Criteria

Process objective, heat treating temperature and temperature accuracy, a time/temperature curve of the heat treating process, dimensions and weight of products, method of loading and unloading, the equipment required for loading and unloading, protective atmosphere requirements, heat treatment capacity requirement (kg/h), oven operating hours, heating method requirements (gas or electrical), etc.

Box Oven

Description

Box ovens are designed for intermittent operation and can be used for most applications with oxidative, protective or active atmospheres. They can be used flexibly for process experiments and one-off heat treatment, as well as the entire spectrum of heat-treating processes for all industries. The method of heating can be that of electrical resistance heating, direct or indirect, or of natural gas firing, direct or indirect. Box oven doors can be operated mechanically or manually. After the end of each heat-treating cycle, the oven chamber is emptied and a new charge is put in. Box ovens are used from 40°C to 3000°C, depending on the temperature scale and other general requirements. We can manufacture ovens up to 1600°C.

Applications

Box ovens can be used nearly for any applications and processes. Although very flexible, box ovens are not always satisfactory in terms of productivity, which must be taken into account when selection is being made.

Buying Criteria

Temperature requirements, dimensions and weight of products, method of loading and unloading, the loading and unloading equipment required, heat treatment capacity requirement (kg/h), oven operating hours, etc.

Car Bottom Furnace

Features

Heating Method:
Chamber Dimensions (mm):
Power [kW]:
Max. Operating Temperature:
Temperature Accuracy in Oven Chamber (tested by TÜV at 18 points at 750°C):
Batch Weight (kg):
natural gas firing, direct
3000 x 3000 x 12000
2500
850 °C


+3 °C
35.000


Description

This is a box furnace with a car bottom of a high loading capacity that can be moved independently and relatively far away from the furnace. When out of the furnace, the car bottom is loaded by a crane, manipulator or manually. The use of a car bottom furnace is particularly advantageous in buildings with an overhead crane.

Applications

Annealing and stress relieving of large-size heavy parts (e.g. for power plants) and steel structures made of alloyed or non-alloyed steel

Buying Criteria

Dimensions and weight of products, temperature, heat treating temperature, temperature accuracy requirement, other process parameters (heating-up and cooling times, etc.).

Forge Furnace

The furnace shown in the photo is a dual chamber forge furnace.

Features

Heating Method:

Power [kW]:
Chamber Dimensions (mm):
Max. Operating Temperature:
Batch Weight:
Thermal Insulation:

Controls:

Application:

natural gas firing, direct; controllable gravity exhaust of flue gases
2 x 500 kW
1100 x 900 x 1500
1250 °C
2 x 300 kg
arched refractory fireclay lining, wear-resistant bottom lining
programmable HAGA temperature controllers, Kromschröder burners and flame guards
heating of copper alloy billets prior to forging


Description

Robust yet stylish, this furnace was designed and built based on the client’s concept. It has a fully automatic firing system that can be started at a push of a button on the operator panel. Venting, ignition and temperature adjustments are performed automatically. The doors are mechanically operated. The required heating programme can be selected easily by the corresponding programme number that is entered.

Application

Preheating to the required temperature of the copper billets that were previously specially alloyed in a vacuum melting furnace, prior to forging to a smaller diameter

Buying Criteria

Handling by a crane and special tools, multiple temperature programmes, ease and speed of operation

Laboratory Furnace

Features of the furnace in the photo

Heating Method:
Power [kW]:
Chamber Dimensions (mm):
Max. Operating Temperature:
Temperature Accuracy in an Oven Chamber:
Thermal Insulation:
Controls:

electric resistance heating
3,5 kW
180x110x420 (8,3 litres)
1150 °C

±3 °C
refractory fireclay lining
analogue or programmable OMRON temperature controller


Description

Furnace type OH-86 can be used wherever short heating-up times and high and accurately controlled temperatures are required. It can be used as an essential piece of equipment for chemical, medical, metallurgical, dental, etc. laboratories pottery, glass art and enamel art studios, as well as precision mechanics and hardening shops.

Methanol Dosing Equipment, MNA 20

Features

Voltage:
Nitrogen Connection Pressure:
Nominal Unit Volume:
Max. Operating Pressure:
Controls:
Connection: 1 × 230 V, 50 Hz; Cont.: 24 V DC
Min.: 3 bar, max.: 15 bar
20 litres
1-2 bar
fully automatic, PLC controls


Description

This nitrogen blanketed methanol dosing equipment provides for the reliable and accurate supply of small doses (2 to 20 litres per hour) of methanol at a constant pressure and without using a motor or any moving parts. This solution eliminates the considerable problems and resulting downtimes that are caused by the mechanical (pumped) dosing of methanol at a rate of 2 to 20 litres/hour. The equipment comprises two nitrogen-blanketed tanks, in which the system is capable of automatically swapping over from one to the other. Empty tanks are refilled by diaphragm pumps. The pressure within the tank is continuously maintained by the nitrogen blanket over the methanol surface. The equipment is fire certified and has a design that is compliant with the European directives and standards. Prior to the installation of such methanol storage and dosing equipment, a walk-over survey should be completed in order to thoroughly assess the fire safety and to define the optimum location for the dosing unit.

Applications

Methanol decomposes at the operating temperature of the furnace. Carbon monoxide, as one of the decomposition products, causes carburisation. An accurate dosage of methanol ensures that carbon is always diffused into the steel surface in the required quantities (coating thickness) and the heat-treating process is run according to the metallurgical process design.

Buying Criteria

The use of a dosing equipment is required because of the carburisation process and the process of creating a carbon atmosphere to prevent decarbonisation during heat treatment.

Pit Furnace with a Nitriding Retort Chamber

Features

Heating Method:
Voltage:
Power:
Chamber Dimensions (mm):
Max. Operating Temperature:
Batch Weight:
Thermal Insulation:
Controls:
Heat Treatment Process:
electric resistance heating, indirect
3 x 400 V, 50 Hz
150 kW
Ø 1200 x 2500
950 °C
1.000 kg
vacuum formed ceramic fibres
PLC programme control
nitridation


Description

This is a directly heated heat-treating furnace that is designed for batch operation and with a vertical, fully gas-tight chamber that is normally sunk below the shop floor level. The furnace door is fitted with a fan for even temperature distribution and a homogenous active gas atmosphere. Nitridation is achieved through the decomposition of the ammonia that is fed into the furnace. To access the furnace chamber, the top cover needs to be removed. The products are mechanically loaded into the furnace and then held by a support frame. The feeding is carried out by an overhead crane.

Pit Furnace Applications

Annealing, carburisation, nitridation, nitrocementation, annealing under protective atmosphere and stress-relief of products of different shapes, sizes and weights hung from grates or segments (such as shafts, splined shafts, piston pins, etc.) or of smaller parts in baskets. It is particularly suitable for small and medium-sized plants that heat treat small batches of non-identical parts. The gases that are used include nitrogen, ammonia, carbon dioxide, methanol and distilled water.

Buying Criteria

Dimensions, quantities and weight of products, the required heat treatment process and its target parameters

Copper Smelting Furnace

Description

Copper smelting furnaces are normally indirectly heated, electric resistance heated or natural gas fired or induction crucible furnaces. The melting point of copper is 1084.62°C. Therefore, such furnaces are designed to have a maximum operating temperature of 1250°C. Furnace designs are usually dynamic and tilting.

Applications

Copper smelting furnaces are normally used by raw material producers.

Buying Criteria

Selection should be based on the size of the batches that are to be melted in one go and the intensity of the use of the melt. The volumetric capacity, output, design and number of furnaces should be defined accordingly.

Top Hat Furnace

Features

Heating Method:
Voltage:
Power:
Chamber Dimensions (mm):
Max. Operating Temperature:
Batch Weight:
Thermal Insulation:
Controls:
Heat Treatment Process:
electric resistance heating
3 x 400 V, 50 Hz
400 kW
3000 x 3000 x 2500
900 °C
20.000 kg
ceramic fibres
PLC, industrial PC, with comprehensive data logging
high-accuracy annealing of bearing rings (without a protective atmosphere)


Description

This is a directly heated heat-treating furnace that is designed for intermittent operation and with a rectangular chamber and floor-level loading. The elevator platforming top hat has ceramic fibre insulation and is fitted with electric resistance heating and a very powerful circulation and cooling fan for ensuring even heat transfer to the charge. Products to be heat-treated are placed in a basket before being put in the hearth by means of an overhead crane. When the loading is complete, the top hat is lowered to enclose the furnace space. After the heat treatment process, the top hat is raised and the batch is removed.

Applications

Annealing and normalisation of the products of various sizes mass-produced by the iron and steel industry

Buying Criteria

Dimensions, quantities and weight of products, the required heat treatment process and its target parameters

Flat Bed Conveyor Oven

The oven shown in the photo was manufactured by Kohnle and was standardised and adapted for use in Hungary by Antal Kft.


Description

In a flat bed conveyor oven, the charge is moved on a continuous-surface conveyor belt through a protective gas or active gas atmosphere (or sometimes an oxidative atmosphere). It is either electrically heated (directly or indirectly) or natural gas fired (directly or indirectly). The charge can be placed directly on the belt without a charge holder. Applications include blank annealing and hardening. For blank annealing, a forming gas of a composition of 25 per cent of nitrogen and 75 per cent of hydrogen is used. This gas is generated by the dissolution of ammonia.

Applications

Flat bed conveyor ovens are chiefly used in mass goods production where small-size, light metal parts need to be heat treated. Applications include fastener manufacturing, household appliance parts manufacturing, etc.

Buying Criteria

Process objective, heat treating temperature and temperature accuracy, a time/temperature curve of the heat treating process, dimensions and weight of products, method of loading and unloading, the loading and unloading equipment required, protective atmosphere requirements, heat treatment capacity requirement (kg/h), oven operating hours, heating method requirements (gas or electrical), etc.

Drying and Cross-Linkage Oven

Features

Heating Method:
Power:
Chamber Dimensions (mm):
Max. Operating Temperature:
Temperature Accuracy in an Oven Chamber:
Batch Weight:
Thermal Insulation:
Controls:

Application:
electric resistance heating
6 kW
800x1200x800
120 °C

± 1 °C
20 kg
90 kg/m3 rock wool
PLC and solid state relays, OMRON temperature control
mainly drying parts for the electrical industry


Description

This oven is similar in design to box ovens with direct electrical heating, the differences being a much lower operating temperature and much more stringent temperature accuracy requirements. An oven is normally categorised as a drying oven (drying stove) up to a temperature of 150°C. A powerful fan is used to force air in and out and to ensure air circulation for even heat distribution. A vacuum application is also possible to remove gas pockets from synthetic resin. First, a vacuum is created without the fan operating, which is then followed by air being let in and convective heating.

Applications

Drying, curing of, and promoting, cross linkage of the resin filler in synthetic resin-bonded bobbins that are used in the electrical industry (power supply units, transformers, motor rotors, etc.)

Buying Criteria

Drying and cross bonding temperature and heat requirements, temperature accuracy requirement, other process parameters (heating-up time, airflow rate, etc.)

Multi-Purpose Box Oven

Features

Heating Method:
Power:
Chamber Dimensions (mm):
Max. Operating Temperature:
Temperature Accuracy in an Oven Chamber:
Batch Weight:
Thermal Insulation:
Controls:
Data Logging:
Application:
electric resistance heating
140 kW
900x650x1200
1000 °C

± 5 °C
600 kg
refractory fireclay lining
PLC, PC
PC, full documentation
case hardening of gearbox parts


Description

This is a fully gas-tight, directly heated box oven integrated with a cooling and hardening chamber. When the door is opened, the charge is loaded in a basket from the feed conveyor on the cooling chamber conveyor by a mechanical feeder. The external door is then closed and the cooling chamber is filled with a protective atmosphere. Then, the fire resistant door between the cooling chamber and the oven chamber opens, allowing the chain-belt conveyor (in the cooling chamber conveyor) to pass the charge from the lock chamber into the oven chamber. The charge is heated by radiant tubes or heating resistors in the oven, while the gas inside the oven is circulated by a fan in the oven top. On completion of the heating and diffusion cycles, the door opens again and the chain-belt conveyor pulls the charge back through the lock chamber onto an elevator platform in the cooling chamber. The elevator platform then descends, submerging the charge into a hardening fluid. The bottom part of the cooling chamber accommodates a hardening vat, allowing the hardening process to be performed without any exposure to the ambient atmosphere. An agitator is used to maintain a uniform temperature distribution in the hardening fluid. The cooling chamber can also be fitted with a circulation fan to cool the carburised parts without hardening while under a protective atmosphere. When cooled or hardened, the charge is unloaded by the chain-belt conveyor through the open door onto the external loading conveyor. It is possible to use a dual cooling chamber design that enables the next charge to be loaded into the oven, while the previous one is still being cooled, which increases oven capacity. It is a highly sophisticated piece of equipment that is capable of performing complex heat treatment processes, and can be fitted with various accessories to create a self-contained process line with excellent productivity. Accessories include a preparatory roller table, handling trolley, washer, pre-heating oven, tempering furnace and deep-freezing unit. The line can be manually operated or fully automatic.

Applications

Sophisticated heat treatment of mass-produced steel products (components, machine parts, etc.) or the heat treatment of consecutive batches in the same oven but under different protective atmospheres (e.g. bright annealing, normalisation, case hardening, nitrocementation, etc.)

Buying Criteria

Process objective, heat treating temperature and temperature accuracy, a time/temperature curve of the heat treating process, dimensions and weight of products, method of loading and unloading, the equipment required for loading and unloading, protective atmosphere requirements, heat treatment capacity requirement (kg/h), oven operating hours, heating method requirements (gas or electrical), etc.

Vacuum Bell Furnace with a Protective Atmosphere

Features

Heating Method:

Voltage:
Power:
Chamber Dimensions (mm):
Max. Operating Temperature:
Batch Weight:
Thermal Insulation:
Controls:





Heat Treatment Process:

Protective Gases:
electric resistance heating, indirect, with a strip heater
3 x 400 V, 50 Hz
260 kW
Ø 1600 x 2500
800 °C
10.000 kg
ceramic fibres
PLC, PC programme control with comprehensive data logging. The operator-in-charge has to enter a dedicated password prior to adding a process programme or intervening in the heat-treating process. Every password entered access and intervention is recorded together with the heat-treating process parameters.
bright annealing of copper alloy strip coils (e.g.: brass, alpaca)
95%N2+5%H2 (protective atmosphere),
ill. 75%N2+25%H2 (active gas)


Description

This is a directly heated heat-treating furnace that is designed for batch operation, with a vertical chamber and floor-level loading. Below the loading level is the furnace bottom, which is fitted with a powerful fan to ensure uniform heat transfer to the charge column. The coils that are to be heat-treated are craned onto the furnace base. When the loading is completed, a protective bell is lowered to enclose the charge column. The furnace proper (i.e. the heating bell) is then craned onto the protective bell. The heating bell has ceramic fibre insulation and is fitted with electric resistance heating. Before the heating-up process is started, a vacuum is generated to evacuate the air from the hearth, which is then filled with protective gas. Then, the circulation fan is started. On completion of the heating-up and holding cycles, the heating bell is removed and replaced with a cooling bell to cool down the charge through the protective bell by using air and then water. With the charge cooled, both bells are removed and the charge is taken from the furnace base. Bell furnaces usually have two bases (stations) and are installed in groups.

Applications

Heat treatment (mainly annealing and normalisation) coiled products (e.g. strips, wires, etc.) in the iron and metal industries; normally used without a protective atmosphere in the steel industry and with active gas in the metal industry to prevent oxidation

Buying Criteria

Dimensions, quantities and weight of products, the required heat treatment process and its target parameters