Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications!

# Perlite Insulation

## Thermal conductivity - k-values - vs. temperature.

Perlite is a type of volcanic glass that expands four to twenty times its original volume and becomes porous when heated. Perlite is suitable in high temperature applications.

Thermal conductivity vs. temperature are indicated in the charts below:

• T(oC) = 5/9[T(oF) - 32]
• 1 W/(m K) = 6.935 (Btu in)/(h ft² °F)

• Refractive Index : 1.5
• Free Moisture : maximum 0.5%
• pH (of water slurry) : 6.5 - 8.0
• Specific Gravity : 2.2 - 2.4
• Bulk Density (loose weight) : depending on the expansion process but usually in the 2-25 lb/ft3 range (32-400 kg/m3)
• Softening Point : 1600 - 2000 oF (871 - 1093 oC)
• Fusion Point :  2300 - 2450 oF (1260 - 1343 oC)
• Specific Heat : 0.2 Btu/lboF (387 J/kgK)

## Related Topics

• ### Heat Loss and Insulation

Heat loss from pipes, tubes and tanks - with and without insulation. Use of materials lke foam, fiberglass, rockwool and more.
• ### Insulation

Calculate heat transfer and heat loss from buildings and technical applications. Heat transfer coefficients and insulation methods available for reduction of energy consumption.
• ### Insulation and Heat Loss from Steam and Condesate Pipe Lines

Heat loss from uninsulated and insulated steam and condensate pipes and tanks. Calculate insulation thicknesses.

## Related Documents

• ### Calcium Silicate Insulation

Thermal conductivity of calcium silicate insulation - temperature and k-values.
• ### Fiberglass Insulation

Thermal conductivity of fiberglass insulation - temperature and k-values.
• ### Insulation Materials - Operating Temperature Limits

Temperature limits for commonly used insulation materials.
• ### Mineral Wool Insulation

Thermal conductivity - k-values - vs. temperature.
• ### Piping - Recommended Insulation Thickness

Recommended insulation thickness for heating systems like hot water and low, medium or high pressure steam systems.
• ### Polyurethane Insulation

Thermal conductivity - k-values - vs. temperature.
• ### Porosity

Volume not occupied by solid material.
• ### Thermal Resistivity and Conductivity

The ability of a material to resist flow of heat.
• ### Water - Thermal Conductivity vs. Temperature

Figures and tables showing thermal conductivity of water (liquid and gas phase) with varying temperature and pressure, SI and Imperial units.

## Search

Search is the most efficient way to navigate the Engineering ToolBox.

## Engineering ToolBox - SketchUp Extension - Online 3D modeling!

Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with older versions of the amazing SketchUp Make and the newer "up to date" SketchUp Pro . Add the Engineering ToolBox extension to your SketchUp Make/Pro from the Extension Warehouse !

We don't collect information from our users. More about

We use a third-party to provide monetization technologies for our site. You can review their privacy and cookie policy here.

You can change your privacy settings by clicking the following button: .

## Citation

• The Engineering ToolBox (2007). Perlite Insulation. [online] Available at: https://www.engineeringtoolbox.com/perlite-insulation-k-values-d_1173.html [Accessed Day Month Year].

Modify the access date according your visit.

7.25.9

.