High Quality Molybdenum Disilicide W Type Mosi2 Electric Heating Elements

What's the Molybdenum disilicide(MoSi2) heating element?
Molybdenum disilicide(MoSi2) heating element is one resistance heating component made from MoSi2 or as the basic material. When it's heated to high temperature under the oxidizing atmosphere, one dense MoSi2film will be formed on its surface to protect the element against oxidizing further. Therefore, the element has unique anti-oxidation property under high temperature atmosphere. The highest temperature can reach 1800°C, the applicable temperature is between 500-1700°C.
Applications: It can be used as heating elements of industrial high-temperature furnace, like ceramics, magnetic materials, glasses, metallurgy, refractories etc.
 
The Specifications and Dimension Mark of MoSi2Heating Element
 
 
When you enquiry, please tell us the following data:
DI: Diameter of Hot Zone(mm)
D2: Diameter of Cold Zone(mm)
Le: Length of Hot Zone(mm)
Lu: Length of Cold Zone(mm)
A: Shank Spacing(mm)

Physical and Chemical Properties
 
1. Physical Property 
2. Chemistry Property
Under high temperature, MoSi2 heating element will form one SiO2 protective film on the surface, which prevents the element from oxidizing continuously. When the element temperature is over 1700 °C, the film becomes melting. It's not suitable for long time use in the temperature range of 400-700°C, otherwise, the element will be powdering for the strong oxidation under low temperature.

3. The Influence of Different Atmospheres
  
Electric Property
 
1. Resistance Property
The resistivity of element rapidly rises as the temperature rises. Under normal operating conditions, the element resistance generally doesn't change with the service life, so the old elements can be used with the new elements together.
 
2. Surface Load
Choosing element surface load based on furnace structure, temperature as well as atmosphere, is the key of optimizing element service life. The below picture shows the relationship among the furnace temperature, element temperature and surface load under the circumstance that thermal element radiation is not hindered. The shadow part is for common surface load and temperature range.
 
Recommend Surface Load
  
Advice of Installation
1.  MoSi2 heating element is very brittle under room temperature but plastic in high temperature, so it's better to install the U type element hanging vertically. The aim is to avoid putting the mechanical stress directly to the Hot Zone of the element, otherwise, the element will be broken easily. If hanging horizontally installation, please use high temperature refractory for support and hang the MoSi2 element horizontally.
2. Please put the taper part of the element bottom into the furnace chamber to avoid local overheating.
3. The lead wire should be a little longer than the linear distance between the element and bus line to avoid putting the stress to the element.
4. Please don't tighten the screw of clamps too much at one time. It can be tightened when the element heats up to high temperature because of the element's plasticity.
5. The temperature of the clip should be less than 200°C, the contact voltage between the clip and the elements less than 0.1V.
6. The distance between the lower end of the clip and the upper surface of the through brick should be more than 50mm, to avoid the radiation heat conducting to the clip.
7. To avoid damage, 170A couldn't be long time used for the element of Ø6/12mm; 300A couldn't be long time used for Ø9/18mm element.
 
 
Notice to Furnace Operation
To avoid high current surges which may cause damage to MoSi2 Heating Elements, the recommend starting procedure as following:
   
  Electric property 
 
1)Resistance property
 The resistivity of element rapidly rises as the temperature rises. Under normal operating conditions, generally the element resistance doesn't change with service time changing. So the old and new elements can be mixed used.
 
 2) Surface load
According to the structure, the temperature and atmosphere in the correct choice of components surface load is the key element to the highest life. The picture shows that the relation among  the surface temperature, the element temperature and surface load under the circumstance that the thermal radiation components is uncrossed. The shaded part is for common surface load-----the temperature range.
 
 
Installation and accessories 
 
1) Advice of Installation
 
Mosi2 heating element is very brittle under room temperature and plastic under high temperature. Therefore,it's the best way for installation of u type element to hand it vertically.Such way is to avoid putting the mechanical stress directly to the Hot zone of the element,otherwise, the element will be broken easliy .If it needs hand horizontally, please chose a spport of high themperature refactory.
 

2) Accessories 
 
The temperature of clip should be less than 200 .C;the contace voltage between the clip and the element should be less than 0.1V. The distance between the lower end of the clip and upper surface of the through brick should be more than 50mm,to avoid the radiation heat conduction to the clip.
 
 
Package and shipping
 
First carton packaging with plastic inside to protect, then wooden packaging outside;
For some special conditions, use iron hanger outside wooden case.
2. Shipping
Fedex/DHL/UPS/TNT for samples, Door-to-Door;
By Air or by Sea for batch goods;
Customers specifying freight forwarders or negotiable shipping methods;
Delivery Time: 3-7 days for samples; 5-25 days for batch goods.