Thermal Performance Across the Temperature Range
Perlite and calcium silicate start close together at low temperature and diverge sharply as the service temperature rises. The conductivity curves below show why the selection depends almost entirely on where the insulation will operate.
| Mean Temperature | Calcium Silicate (170-250 kg/m³) | Expanded Perlite Board | Perlite Loose Fill |
|---|---|---|---|
| 100°C | 0.058 W/m·K | 0.062-0.067 | 0.050 W/m·K |
| 200°C | 0.065 | 0.078-0.084 | 0.056 |
| 400°C | 0.088 | 0.100 | 0.068 |
| 600°C | 0.110 | 0.135 | 0.082 |
| 800°C | 0.135 | 0.190 | 0.100 |
Reading the table: at 100°C the two rigid materials are effectively equal, and loose-fill perlite is actually the best insulator. By 400°C calcium silicate has pulled ahead of perlite board, and by 800°C it is 30-40% better — while perlite board is approaching the upper end of its practical range. Loose-fill perlite holds its numerical advantage at every temperature, but it cannot be used in the same applications: it has no structural strength, settles under vibration, and requires containment that rigid board does not.
Mechanical Properties — Where the Two Diverge Most
The decisive difference between these materials is not thermal but mechanical. Perlite is a lightweight, friable material; calcium silicate is a load-bearing rigid board. This gap defines which applications each can serve.
| Property | Calcium Silicate Board | Perlite Board | Perlite Loose Fill |
|---|---|---|---|
| Compressive strength | ≥2.0 MPa (up to 13) | 0.2-0.8 MPa typical | None — granular |
| Form stability | Rigid board and machined shapes | Rigid but friable, chips at edges | Flows; settles under vibration |
| Load-bearing | Yes — carries refractory and brick loads | Limited; not for structural duty | No |
| Machining | CNC to ±0.5mm, custom shapes | Cut only; limited profile capability | N/A |
| Fire classification | EN 13501-1 A1 | A1 (non-combustible) | A1 |
The practical consequence: perlite board is specified where the insulation carries nothing but its own weight and the duty stays below roughly 650°C — often in fire door cores, chimney linings, and moderate-temperature backup. Calcium silicate is specified wherever the insulation must carry load, survive mechanical abuse, hold precise dimensions after machining, or operate on the hot side of the 650°C line. The gap in compressive strength — roughly 3-15x depending on grade — is what usually decides the specification, not the conductivity difference.
Moisture Behavior and Service Life
Both materials are hygroscopic mineral insulations, but they recover from moisture differently — and that difference shows up in long-term thermal performance.
Calcium silicate: absorbs water by capillary action through its microporous structure, and dries with full property recovery because the xonotlite crystal structure is not degraded by water. In service it must be kept dry — which is why outdoor installations specify water-repellent treated board plus sealed jacketing. Documented service life with proper jacketing exceeds 25 years.
Perlite board: the perlite granules are bound with a binder (often sodium silicate or a cementitious matrix). Water absorption degrades the binder over repeated wet-dry cycles, and the friable structure can crumble at edges during handling and maintenance access. In dry, protected indoor service perlite board performs reliably for its rated life; in wet or high-humidity service it is the weaker choice.
Perlite loose fill: sheds water on the surface but holds moisture in the void spaces between granules, and it settles under vibration — which leaves the top of the cavity uninsulated. This settling is why loose-fill perlite applications require periodic top-up, and why the effective insulation over the service life is lower than the installed value.
Cost Comparison and Where Each Material Fits
Perlite insulations are generally lower in first cost than calcium silicate at the same thickness, which makes them attractive for budget-constrained projects within their temperature range. The comparison below puts the trade-off in context.
| Application | Temperature | Recommended Material | Reasoning |
|---|---|---|---|
| Fire door core | ≤650°C | Either — perlite common | Perlite board's friability is acceptable inside a door leaf; calcium silicate used where superior core strength is needed |
| Chimney and flue lining | ≤650°C | Perlite (board or fill) | Cost-effective; loose fill suits irregular voids |
| Kiln backing insulation | 900-1100°C | Calcium silicate | Perlite beyond practical range; calcium silicate carries brick load |
| Steel ladle backup | 1000°C, load-bearing | Calcium silicate (MF-HD) | Compressive strength requirement rules perlite out |
| Pipe insulation, steam service | >250°C | Calcium silicate sections | Pre-formed rigid half-shells; perlite unsuitable for pipe form |
| Cryogenic and cold service | <0°C | Perlite (fill), cellular glass | Perlite's low-temperature performance and fill capability suit cryogenic vessels |
The pattern across the table: perlite wins on cost where the duty is moderate and non-structural; calcium silicate wins wherever temperature exceeds ~650°C or the insulation must carry load. Projects frequently use both — perlite in the moderate-temperature sections and calcium silicate in the high-temperature or load-bearing zones — which is a legitimate design strategy rather than a compromise.
Frequently Asked Questions — Calcium Silicate vs Perlite
Can perlite and calcium silicate be used together in one lining?
Yes, and it is common practice in composite linings. A typical arrangement uses perlite in the cooler backup zone and calcium silicate in the higher-temperature or load-bearing position. Each layer performs in its own temperature band, which often produces a lower total material cost than specifying calcium silicate throughout. Specify each layer with its own grade, density, and conductivity basis.
At what temperature does perlite insulation stop being suitable?
Expanded perlite board products are typically rated to about 650°C maximum service temperature, with the limit set by the binder system — above that the binder degrades. (Note that 870°C, sometimes quoted for perlite, refers to the temperature at which crude perlite is expanded during manufacture, not the finished board's service limit.) Calcium silicate covers 1000-1100°C, so the crossover point for high-temperature duty sits right at perlite's ceiling — which is why the two materials rarely compete directly in the 650°C+ range.
Which material is better for fire door cores?
Both are non-combustible (A1) and both are used in fire door cores. Perlite board is common because it is lower cost and the core is protected inside the door leaf. Calcium silicate is specified where the core needs higher screw-holding strength for heavy hardware, greater dimensional tolerance (±0.5mm on machined edges), or where the assembly rating requires a denser core. The certified rating always comes from the door manufacturer's full assembly test, not the core material alone.
Is loose-fill perlite better than rigid calcium silicate board?
Not better — different. Loose fill has the lowest conductivity of the three and can fill irregular cavities that rigid board cannot, which is why it is used in cryogenic vessels, masonry cavities, and chimney voids. But it has no structural strength, settles under vibration (requiring periodic top-up), and cannot be used where the insulation must carry load or hold a machined profile. Rigid board and loose fill solve different problems.
Installation and Handling Differences
Site teams notice the difference between these materials within the first hour of installation. The handling profile affects labor hours, breakage, and the quality of the finished insulation envelope.
| Installation Factor | Calcium Silicate Board | Perlite Board |
|---|---|---|
| Cutting | Carbide-tipped saw; clean edges, score-and-snap for thin board | Saw or knife; friable edges crumble, dustier |
| Edge integrity | Holds square edges through handling | Chips and crumbles at corners without careful handling |
| Fastening | Holds screw threads and banding tension | Screws can pull through; banding compresses the surface |
| Breakage in transit | Low — rigid with impact resistance | Higher — friable material cracks under impact |
| Custom shapes | CNC machined to ±0.5mm | Limited profile capability |
| Rework after damage | Section replacement is clean | Damaged areas may crumble further during removal |
The consequence for project planning: perlite board requires more careful handling and generates more breakage allowance in the bill of quantities, which narrows its first-cost advantage. Where the insulation will be walked on, exposed to mechanical contact, or installed around complex geometries requiring machined fit, calcium silicate's handling profile typically produces a lower installed cost despite the higher material price.
Specification Checklist for Either Material
Whichever material the design selects, the specification clause must state the same four items to be comparable and auditable.
- The material standard and grade. For calcium silicate: ASTM C533 (Type I or II), EN 14306, or GB/T 10699, plus the density grade. For perlite: the applicable product standard and density.
- The temperature rating with its basis. State the maximum continuous service temperature and confirm the peak operating condition does not exceed it. For calcium silicate, note whether the 1000°C or 1100°C grade is specified.
- Thermal conductivity at a stated mean temperature. A conductivity value without its mean temperature is not a specification. Include the test method (ASTM C518 or EN 12667).
- Batch certificate requirement. Require batch test certificates with measured values matching the delivered pallet labels — this is what converts the specification into an auditable requirement at receiving inspection.
With these four items in the clause, quotations from different suppliers become directly comparable, and the delivered material can be verified against the design basis. Mingfa's technical team reviews comparison specifications free of charge and confirms grade, density, and certificate requirements before quotation.
For a project-specific comparison, send the operating temperature, geometry, and mechanical duty to the engineering team. The written response covers the recommended material per position in the lining, the grade and density, the thickness calculation basis, and the documentation that would accompany delivery — enough to complete the specification clause without further back-and-forth. Free A4 samples of both standard and high-density calcium silicate grades are available for evaluation, and batch test certificates ship with every order.
Worked Example: Selecting Between the Two for a Kiln Backup Layer
The example below walks through a selection decision with the numbers a plant engineer would actually use. It illustrates where the two materials diverge in practice.
The duty: a rotary kiln with a burning-zone hot face at 1450°C refractory working lining, a backing temperature of approximately 850°C at the interface between the working brick and the backup insulation, and a steel shell that must stay below 300°C. The backup layer carries the compressive load of the brickwork above it.
Temperature check: the backup layer sees 850°C at its hot face and roughly 250°C at its cold face, giving a mean near 550°C. Perlite board's practical ceiling around 650°C is close enough to the hot face that its binder sits near the edge of its thermal envelope for the full campaign. Calcium silicate's 1000-1100°C rating puts the same duty comfortably inside its range, with margin for process excursions.
Load check: the backup layer supports the working brick lining. Calcium silicate at 230-270 kg/m³ provides ≥2.0-2.5 MPa compressive strength, which is the design basis for carrying brickwork. Perlite board at 0.2-0.8 MPa typical is an order of magnitude below that and is not specified for load-bearing backup in this position.
Conductivity at the mean: at 550°C mean, calcium silicate runs approximately 0.100 W/m·K while perlite board runs about 0.120. Over a 50mm layer, the heat flux difference is roughly 15-18% in calcium silicate's favor — a real but secondary effect compared with the temperature margin and load capacity that decide the specification first.
The conclusion: calcium silicate is specified. Perlite would be the candidate if the same kiln had a moderate-temperature duty below 800°C at the backing interface and the insulation carried no structural load — for example in a preheater duct or a chimney section. That contrast is the selection rule in one line: perlite for moderate-temperature, non-structural duty; calcium silicate for high temperature or load.
Industry Application Matrix
The matrix below maps common industrial applications to the material that normally serves each position, based on the temperature and mechanical requirements of the duty.
| Industry | Application | Typical Choice | Deciding Factor |
|---|---|---|---|
| Cement | Rotary kiln backup insulation | Calcium silicate | Load-bearing at 850°C interface temperature |
| Cement | Preheater and duct insulation | Either | Temperature and load both moderate; cost decides |
| Steel | Ladle and tundish backup | Calcium silicate (MF-HD) | High compressive load under working lining |
| Glass | Furnace bottom and sidewall | Calcium silicate (MFBL) | Load, temperature, and low-iron chemistry requirement |
| Aluminum | Reduction cell sidewall | Calcium silicate (MFDJ) | Fluoride resistance plus controlled thermal profile |
| Power | Boiler casing and steam lines | Calcium silicate | Service above 250°C; rigid pipe sections |
| Petrochemical | Fired heater and reformer casing | Calcium silicate | Continuous high temperature plus CUI management |
| Building | Fire door core | Perlite common; calcium silicate where core strength needed | Assembly rating and hardware load |
| Building | Chimney and flue lining | Perlite (board or fill) | Moderate temperature, cost-sensitive, irregular cavities |
| Cryogenic | Cold-box and vessel insulation | Perlite fill | Low-temperature performance and fill capability |
Two patterns run through the matrix. First, everything above roughly 650°C or under mechanical load resolves to calcium silicate — the material's rated range and compressive strength are what qualify it. Second, perlite holds the moderate-temperature, non-structural, cost-sensitive segment, particularly in building applications and cryogenic fill. Plants with mixed duty across a site typically use both, and the specification documents the material per position rather than globally.
Supply and Availability Considerations
Sourcing logistics differ between the two materials in ways that affect project planning, particularly for buyers importing into the Middle East, Africa, and Southeast Asia.
Calcium silicate supply: production is concentrated in China, Europe, and Japan, with Chinese manufacturers supplying the majority of export volume at competitive pricing. The supply chain is fully domestic to China — high-purity silica sand and limestone are quarried and processed in regional industrial clusters — which removes imported-raw-material exposure. Standard products ship in 15-20 working days; custom shapes and OEM orders in 20-30.
Perlite supply: expanded perlite is produced in many countries from locally mined crude perlite, so regional supply is generally available and lead times are short. This local availability is part of perlite's cost advantage in markets with domestic production. For project buyers, the trade-off is that perlite suppliers are often regional rather than specialized manufacturers, which affects the depth of batch documentation and technical support available.
Documentation depth: for project quality files and vendor qualification, the difference matters. Calcium silicate manufacturers characteristically issue batch test certificates with measured values per ASTM method and batch numbers matching pallet labels, plus ASTM C533 compliance documentation and EN 13501-1 A1 classification. Buyers specifying perlite should confirm the equivalent documentation set is available before committing — the requirement is the same, but the supply base is more diverse.
Contact the engineering team for a project-specific material recommendation with the documentation set included.
Calcium Silicate vs Perlite Insulation | Industrial Comparison
Perlite insulation is common in lower-temperature industrial settings, often appearing as molded pipe sections, block insulation, and loose-fill material. Calcium silicate and perlite are both inorganic and non-combustible, but they differ significantly in temperature range, mechanical strength, and moisture behavior. This comparison examines where each material fits in industrial applications, from kilns and furnaces to process piping and fireproofing.
1. Material Basics
Calcium silicate and perlite are both inorganic, non-combustible insulation materials, but they differ fundamentally in structure. Calcium silicate is a chemically bonded crystalline board formed by autoclave curing. Perlite is expanded volcanic glass granules bound together with cement or sodium silicate. This structural difference determines their respective temperature limits, strength, and moisture resistance.
Key Takeaways
- Temperature range: Calcium silicate handles up to 650-1100°C continuously; perlite with organic binders is limited to ~260°C, with sodium silicate binders to ~650°C.
- Mechanical strength: Calcium silicate offers compressive strength of 2-10+ MPa as a monolithic crystalline board; perlite's granular/binder structure is weaker and prone to crumbling under load.
- Moisture resistance: Perlite's open granular structure absorbs water readily, compromising insulation performance; calcium silicate's dense crystalline matrix resists moisture ingress.
- Mingfa advantage: Mingfa calcium silicate is a single-material board without aggregate/binder interfaces, eliminating the weak points that limit perlite's service life and temperature ceiling.
Mingfa Lab Verified (2024): Performance data referenced on this page is validated through in-house testing at our Shandong facility per ASTM and EN test methods. 34+ years of continuous calcium silicate R&D since 1991. Quality assurance details
Calcium Silicate
Calcium silicate insulation is produced by reacting calcareous (CaO) and siliceous (SiO2) raw materials in an autoclave at 190-220deg;C and 12-18 bar. The process forms xonotlite crystals (6CaO·6SiO2·H2O) that interlock into a rigid, load-bearing matrix. Reinforcing fibers (glass or carbon) are integrated during production. The material is homogeneous, with no aggregate/binder interface. Density ranges from 170 to 900 kg/m3, controlled by filter-press pressure during forming.
Perlite
Perlite insulation starts with volcanic glass ore that is crushed and heated to 870-1100deg;C. The trapped water vaporizes, expanding the particles to 4-20 times their original volume, creating closed-cell glassy spheres. For molded products, these expanded perlite granules are mixed with a binder (cement, sodium silicate, or organic resin) and pressed into boards, pipe sections, or blocks. The binder limits the product's temperature and strength. Typical density for molded perlite insulation is 32-400 kg/m3, with insulation grades commonly at 200-230 kg/m3.
Structural difference: Calcium silicate is a continuous crystalline matrix; perlite is an aggregate of granules held together by a separate binder phase. This difference drives every performance comparison between the two materials.
2. Temperature Performance
| Temperature Property | Calcium Silicate (Mingfa) | Molded Perlite (ASTM C610) |
|---|---|---|
| Max continuous service (standard) | 1000-1100deg;C (grade dependent) | ~650deg;C (binder-limited) |
| Raw material softening point | ~800deg;C (xonotlite to wollastonite) | 871-1093deg;C (perlite glass) |
| Raw material fusion point | ~1540deg;C (wollastonite) | 1260-1343deg;C |
| Binder degradation onset | None (no organic binder) | 200-650deg;C (depends on binder type) |
| Linear shrinkage at max temp | ≤2% (24 hrs at rated temp) | Not specified at elevated temp (binder fails first) |
Sources: [1] ASTM C533-17(2023); [2] EN 14306:2015+A1:2018; [3] Manufacturer test data — Mingfa QC Laboratory, Laizhou, Shandong. Standards & certifications
Perlite's practical temperature limit is set by its binder, not by the expanded perlite granules themselves. Cement-bonded perlite degrades above 500-600deg;C. Sodium silicate binder fails around 650deg;C. Organic resin binders fail at even lower temperatures (200-300deg;C). While loose-fill perlite (without binder) can withstand temperatures up to approximately 1000deg;C, molded perlite products are binder-limited.
Calcium silicate, with no separate binder phase, has consistent performance across its entire temperature range. The xonotlite crystal structure is stable up to 750-800deg;C, where it transitions to wollastonite (a mineral with its own useful thermal properties) without significant dimensional change.
3. Mechanical Strength
| Strength Property | Calcium Silicate | Molded Perlite |
|---|---|---|
| Compressive strength | 0.5 - 13.0 MPa | 0.5 - 1.6 MPa (cold crushing) |
| Flexural strength | 0.3 - 5.0 MPa | 0.35 - 0.84 MPa |
| Load-bearing capability | Yes; walkable, supports structural loads | No; crushes under concentrated load |
| Abrasion resistance | Good; rigid surface resists abrasion | Poor; granules powderize under abrasion and vibration |
| Edge integrity | Good; clean cuts, minimal crumbling | Poor; edges crumble during handling and cutting |
Calcium silicate is a load-bearing insulation material. Standard boards (200-250 kg/m3) can be walked on during installation without damage. High-density grades (MF-HD at 800-900 kg/m3) achieve compressive strengths of 8-13 MPa, sufficient for steel ladle backup lining and structural insulation applications.
Perlite, as a granular aggregate bound by a secondary phase, has fundamentally lower strength. The binder-to-aggregate interface is the weak point. Under mechanical load, vibration, or thermal cycling, perlite insulation tends to powderize at the surface, losing thickness and insulating value over time. It is not suitable for load-bearing applications or installations subject to vibration (such as rotary kilns or heavy industrial equipment).
4. Thermal Conductivity
| Mean Temperature | Calcium Silicate (k ~ 0.056 + 0.00011t W/m·K) | Molded Perlite (Typical, 200-230 kg/m3) |
|---|---|---|
| 100deg;C | 0.067 W/m·K | 0.048-0.060 W/m·K |
| 200deg;C | 0.078 W/m·K | 0.065-0.085 W/m·K |
| 400deg;C | 0.100 W/m·K | 0.110-0.140 W/m·K (estimated from composite data) |
At low temperatures (below 200deg;C mean), perlite has a slight thermal conductivity advantage, similar to mineral wool. The closed-cell structure of expanded perlite provides good insulating properties at ambient and moderately elevated temperatures.
However, perlite's thermal conductivity rises faster with temperature than calcium silicate's. This is because the large inter-granular pores in perlite (100-1000 micrometers) promote radiative heat transfer and natural convection within the insulation at elevated temperatures. Research on xonotlite-perlite composites shows perlite's thermal conductivity reaching 0.128 W/m·K at 800deg;C, compared to approximately 0.100-0.110 W/m·K for calcium silicate at the same mean temperature. At temperatures above 500deg;C, calcium silicate provides better thermal performance per millimeter of thickness.
5. Water Resistance
| Water Property | Calcium Silicate | Perlite |
|---|---|---|
| Water absorption (by volume) | 5-15% | Up to 40% |
| Effect of water on insulation value | Moderate reduction; recovers partially on drying | Severe; water fills inter-granular pores, conductivity multiplies |
| Hydrophobic formulation available | Yes | Limited; binder chemistry may limit water-repellent additives |
| CUI risk (carbon steel) | Low-moderate (alkaline pH 8-10) | Moderate-high (water retention at pipe surface) |
| Compatibility with stainless steel | Low-chloride grades available (less than 50 ppm) | Good; chemically inert, low chloride content |
Water resistance is one of the largest performance gaps between these two materials. Perlite absorbs significantly more water than calcium silicate because water fills the open inter-granular pore space. Once wet, perlite's thermal conductivity increases dramatically (water conducts heat roughly 25 times better than still air). The insulation value effectively collapses in saturated perlite, and drying is slow because the tortuous pore structure traps moisture.
For outdoor installations, pipework exposed to weather, or equipment subject to washdown, calcium silicate's lower water absorption and hydrophobic formulation options provide a significant reliability advantage.
One area where perlite has an edge: it is chemically inert and contains negligible chlorides. For austenitic stainless steel where chloride stress corrosion cracking (Cl-SCC) is the primary concern, perlite poses lower risk than standard calcium silicate. However, calcium silicate with low-chloride formulation (similar to what Mingfa produces for stainless steel applications) closes this gap.
6. Cost and Availability
| Cost Factor | Calcium Silicate | Molded Perlite |
|---|---|---|
| Raw material cost | Moderate; lime and silica are abundant | Low; perlite ore is inexpensive and widely mined |
| Manufacturing energy | High; autoclave curing (190-220deg;C, 5-8 hrs) | Moderate; ore expansion at 870-1100deg;C, then low-energy molding |
| Finished product price | Higher | 30-50% lower than calcium silicate |
| Transport cost | Higher; denser, heavier product | Lower; lightweight, more m3 per ton |
| Availability | Fewer manufacturers; specialized product | Widely available; many regional producers |
| Service life | 25+ years | 10-20 years (faster degradation if wet or vibrated) |
Perlite insulation is cheaper to buy. Raw perlite ore is inexpensive, expansion is a relatively low-cost thermal process, and molding with binder is straightforward. Multiple regional producers keep prices competitive. For budget-constrained projects where operating conditions are mild (dry, below 500deg;C, no mechanical load), perlite can be an adequate, cost-effective choice.
However, perlite's lower strength leads to higher handling damage and installation waste. Its shorter service life in demanding conditions means more frequent replacement. As with mineral wool, the total cost of ownership over a facility's lifetime may favor calcium silicate if the application involves moisture exposure, vibration, or temperatures above 500deg;C.
7. Application Guide
| Application | Recommended Material | Why |
|---|---|---|
| Rotary cement kilns | Calcium silicate | Temperature above 650deg;C, mechanical load, vibration; perlite fails on all three |
| Industrial furnaces (backup lining) | Calcium silicate | Temperature exceeds perlite limit; rigid board required for refractory backup |
| Steam pipes (150-350deg;C), indoor | Either; perlite if budget-driven | Both handle the temperature; perlite is cheaper; calcium silicate more durable long-term |
| Steam pipes, outdoor | Calcium silicate | Water ingress risk; perlite absorbs too much water through jacket damage |
| Fireproof doors | Calcium silicate | Higher strength for screw retention; perlite crumbles at edges during fabrication |
| Non-ferrous metal casting (aluminum contact) | Calcium silicate | High-purity grades available; perlite incompatible with molten metal contact |
| Tank base insulation (ambient to 200deg;C) | Perlite (cost-effective) | Temperatures low, no vibration; perlite's low cost and light weight are advantages here |
| Loose-fill cavity insulation | Perlite (or loose mineral wool) | Calcium silicate is not available as loose fill; perlite pour-in is standard for this use |
| High-temperature pipe (above 500deg;C) | Calcium silicate | Perlite exceeds its maximum service temperature |
8. Frequently Asked Questions
Which handles higher temperatures, calcium silicate or perlite?
Calcium silicate handles higher temperatures. Molded perlite insulation products (bonded with cement, water glass, or organic binders) are limited to approximately 650deg;C by their binder systems. Calcium silicate (xonotlite-based) is stable up to 1000-1100deg;C. For industrial furnaces, kilns, and high-temperature process equipment above 650deg;C, calcium silicate is the appropriate choice.
Is perlite insulation cheaper than calcium silicate?
Yes, perlite insulation typically costs 30-50% less than calcium silicate in material price. Expanded perlite is an inexpensive raw material, and manufacturing is less energy-intensive (no autoclave curing). However, perlite's lower temperature limit, lower strength, and higher water absorption mean it is not a direct substitute for calcium silicate in demanding industrial applications.
Which insulation is better for outdoor pipework?
Calcium silicate is better for outdoor industrial pipework. Perlite absorbs more water (up to 40% by volume), which degrades its thermal performance and promotes corrosion under insulation (CUI). Calcium silicate has lower water absorption and hydrophobic formulations are available. For indoor, dry applications where temperature does not exceed 650deg;C, perlite can perform adequately at lower cost.
Specify Calcium Silicate for Your High-Temperature Application
For applications above 650deg;C where perlite cannot perform, Mingfa provides calcium silicate boards, pipe sections, and custom parts. Contact our technical team for product selection guidance.
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About the Author — Mingfa Insulation Technical Team
Mingfa Insulation engineering team — 34+ years calcium silicate R&D and manufacturing since 1991. ~20 national patents. lzmfgr@163.com