Centrifugal high-temperature re-circulation fans are equipped with impellers that can have forward curved blades, backward curved blades or radial blades.

The impeller with backward curved blades can move a high quantity of air with medium pressure.

The backward curved blades make the impeller very robust and long-lasting which can also be suited to various temperatures and performances.

The main features of impellers with backward curved blades are high efficiency, high reliability and low noise levels.

Due to its shape, the impeller with backward curved blades is used when, from the slots on the sidewalls of the furnace, a high outlet airspeed is required.

Rimor S.r.l. manufactures impellers with backward curved blades that can operate up to a temperature of 850°C.

Centrifugal high-temperature re-circulation fans are equipped with impellers that can have forward curved blades, backward curved blades or radial blades.

The impeller with forward curved blades can move a high quantity of air with a very low rotation.

This feature means that the impeller is very durable, does not transmit vibrations and limits noise emissions.

Due to its shape, it supplies air on the whole blade making it the most adequate among all types of impellers when uniformity in the furnace is required.

The impeller with forward curved blades can be built with reinforcements making it very sturdy so that it can be adapted to different temperatures and performance requirements.

Rimor S.r.l. manufactures impellers with forward curved blades that can operate up to a temperature of 850°C.

Centrifugal high-temperature re-circulation fans are equipped with impellers that can have forward curved blades, backward curved blades or radial blades.

The impeller with radial blades is very sturdy that can be adapted to different temperatures and performance requirements.

The main features of radial blade impellers are its ease of construction and ease of cleaning. It is defined as a self-cleaning impeller.

The radial blade centrifugal impeller has a medium-low performance given by its construction itself.

The radial blade centrifugal impeller can be build through die-casting.

Rimor S.r.l. manufactures impellers with radial blades that can operate up to a temperature of 950°C.

Axial/helicoidal impellers can be built with welding or die-casting processes.

The welded axial/helicoidal impeller is entirely designed and built in-house by Rimor: for this reason, we can offer different performances based on what is required by the project.

Rimor S.r.l. manufactures axial/helicoidal welded impellers that can operate up to a temperature of 850°C.

Axial/helicoidal impellers can be built with welding or die-casting processes.

The axial/helicoidal die-cast impeller is very robust and, depending on the alloy used, it can operate at extremely high temperatures.

Rimor S.r.l. manufactures axial/helicoidal die-cast impellers that can operate up to a temperature of 950°C.

Rimor S.r.l. has always given great importance to the cooling of the motor on high temperature re-circulation fans, designing and building over the years, different types of cooling systems based on the needs and type of re-circulation fan built.

The type of cooling used mainly on the construction of axial high temperature re-circulation fans – but not only – is defind as air cooling with long shaft motor.

Thanks to many years of experience, Rimor S.r.l. has designed and introduced on the market an aluminum heatsink that placed on the motor shaft is able to cool the heat both by conduction and by convection since it acts on the motor shaft itself, making it possible to keep the electric motor ” cold ”, thus obtaining a reliable product over time that is very robust and with practically no management costs.

Rimor S.r.l. has always given great importance to the cooling of the motor on high temperature re-circulation fans, designing and manufacturing over the years, different types of cooling according to the needs and the type of agitator built.

The type of cooling used on the construction of centrifugal high temperature re-circulation fans – but not only – is called air cooling for Unel Mec motors.

The air cooling for Unel Mec motors for high temperature re-circulation fans consists of the special construction of the pad and the impeller in order to couple the impeller with standard Unel Mec motors, for easy maintenance and replacement without machine downtime.

Air cooling uses an aluminum heat sink that placed on the motor shaft is able to cool the heat both by conduction and by convection since it acts on the motor shaft itself, making it possible to keep the electric motor “cold. ” Thus obtaining a reliable product over time, very robust and with practically no management costs.

Rimor S.r.l. has always given great importance to the cooling of the motor on high temperature agitators, designing and manufacturing over the years, different types of cooling according to the needs and the type of recirculation fan built.

The type of cooling used on the construction of axial or centrifugal high temperature re-circulation fans especially where the temperature is higher than 750/800 ° C is called water cooling.

Water cooling for high temperature re-circulation fans consists in the construction of motors with a special coupling side flange capable of containing water to dissipate the heat that occurs by convection or conduction on the motor shaft.

This type of cooling allows to keep the electric motor “cold”, thus obtaining a reliable product over time that is very robust and with very low operating costs.

Transmission is defined as direct when the impeller is directly coupled to the motor shaft.

Rimor S.r.l. thanks also to dedicated software, based on the temperature, the rotation speed and the pressures involved, can size and choose the most suitable materials for the construction of the motors.

Direct transmission is an advantageous solution as there are no transmission parts to be maintained, guaranteeing continuous performance over time.

Another advantage of direct transmission is the compactness of the product which is often a strong point.

Direct drive for re-circulation fans is a technology that can be used for centrifugal and axial re-circulation fans, for furnaces up to temperatures of 1000°C.

Thanks to investments in R&D over the years, Rimor S.r.l. is able to build re-circulation fans with direct transmissions for furnaces with temperatures up to 600°C using standard UNEL MEC motors thus giving the possibility of having spare parts ready for delivery.

The transmission is defined as direct when the impeller is directly coupled to the shaft of the Unel Mec motor.

Rimor S.r.l. thanks also to dedicated software, based on the temperature, the rotation speed and the pressures involved, it was able to size and choose the most suitable materials for the construction of the motors.

Direct transmission is an advantageous solution as there are no transmission parts to be maintained, guaranteeing continuous performance over time.

Another advantage of direct transmission is the compactness of the product which is often a strong point.

Direct drive for re-circulation fans is a technology that can be used for centrifugal and axial re-circulation fans for furnances with temperatures up to 1000°C.

Thanks to investments in R&D over the years, Rimor S.r.l. is able to build re-circulation fans with direct transmissions for furnaces with temperatures up to 600°C using standard UNEL MEC motors thus giving the possibility of having spare parts ready for delivery.

The transmission is executed with a joint when the impeller is coupled on a support made up by a shaft and bearings and the transmission with the motor is made through a coupling joint.

Rimor S.r.l. can manufacture transmissions with joints by dimensioning – by using dedicated software – shafts and bearings, choosing the most appropriate materials and thus ensuring the duration and effectiveness of the system.

The transmission with joint is an advantageous solution as it allows the use of standard UNEL MEC motors but allows to have the bearing closer to the furnace in order to guarantee continuous performance over time.

A weak point of this type of trasmission is the size of the cluster which may not be suitable for all environments.

The joint trasmission for re-crculation fans is a technology that can be used for centrifugal and axial re-circulation fans for furnaces with temperatures up to 1000°C.

The transmission is executed with belts and pulleys when the impeller is coupled on a support made uo by the shaft and bearings and the transmission with the motor is executed through belts and pulleys.

Rimor S.r.l. can manufacture transmissions with belts and pulleys by dimensioning – by also using a dedicated software – the shafts and
bearings, choosing the most appropriate materials and thus ensuring the duration and effectiveness of the system.

The transmission with belts and pulleys is an advantageous solution as it allows you to use standard UNEL MEC motors but allows to maintain the bearing closest to the furnace in order to guarantee continuous performance over time.

A weak point of this type of trasmission is the cluster size which may not be suitable for all environments.
The trasmission with belts and pulleys for re-circulation fans is a technology that can be used for centrifugal and axial re-circulation fans for furnaces with temperatures up to 1000°C.

In more complex applications, the re-circulation fans are equipped with a perfect seal on the shaft, equipped with a pressurized chamber with special grease or nitrogen capable of compressing the gas inside the fan casing and thus guaranteeing a perfectly sealed fan.

Rimor Srl, in the case of liquid sealing and dust sealing has studied and patented a sealing system for the outside through the creation of a vacuum system near the motor shaft that blocks the introduction of the gas contained in the fan in an outdoor environment, without requiring any maintenance.

This type of seal is available in the following models:

• Atex model;
• Water jacket model;
• ATEX zone 21 model;
• ATEX zone 22 model;

Rimor S.r.l. thanks to its own technical department and to the computational softwares used can calculate the heat dissipation in order to design the high temperature re-circualtion in a complete manner.

High-temperature re-circulation fans are designed and manufactured to work at very high temperatures. This means that great importance is attached to the re-circulation fan insulation due to two factors:

• to keep the heat inside the furnace without having dissipation to the outside, thus keeping the furnace performance high and not affecting the work cycle
• to ensure that the external part of the re-circulation fan is cold so that as per conduction the heat is transferred to the apparatus outside the furnace

Rimor S.r.l. has designed and manufactured over the years different types of buffers with the most suitable materials for the different temperatures. The buffer can be made with visible fiber or closed fiber.

In the manufacturing process of the buffer, great importance is given to the heat transmission that can occur as a leak between the furnace and the buffer itself, which is often a critical point.

The in-house design and manufacturing are strengths of Rimor which allow to make buffers with a circular or square shape to better suit the furnace.

These types of buffers are very reliable over time, without maintenance costs.

Rimor, thanks to its technical department can calculate the heat dissipation with precision in order to design and built entirely the high-temperature re-circulation fans.

The high temperature re-circulation fans are designed and built to work at very high temperatures. This means that great importance is given to the insulation of the re-circulation fans due to two factors:

• to keep the heat inside the furnace without dissipating it to the outside, thus keeping the furnace’s performance high and not affecting the work cycle;
• to ensure that the external part of the re-circulation fan is cold so that the heat is transmitted by conduction to the equipment outside the furnace.

Rimor S.r.l. has designed and built over the years different types of buffers with the most suitable materials to work at different temperatures. The buffer can be constructed with visible fiber or closed fiber.

In the manufaturing of the buffer, great importance is also given to the transmission of heat that can occur as a leakage between the furnace and the buffer itself, which is often a critical point.

The design and internal construction are the strengths of Rimor S.r.l. and allow us to build buffers with a circular shape in order to better adapt to the furnace.

This type of buffer is very reliable over time, with no maintenance costs.

Rimor, thanks to its technical department can calculate the heat dissipation with precision in order to design and built entirely in-house the high-temperature re-circulation fans.