1. Pipe Insulation Product Overview
Mingfa calcium silicate pipe insulation is supplied as pre-formed half-shell sections — two matching semi-cylindrical halves that clamp around the pipe to form a complete insulation layer. This half-shell pipe cover design enables rapid installation, easy inspection access, and simple replacement of individual sections without disturbing adjacent insulation.
Standard Pipe Sizes
Half-shell sections are stocked for standard pipe diameters from 1/2″ (DN15) to 24″ (DN600), matching both imperial (NPS) and metric (DN) pipe sizing. Sections are machined to fit the actual outside diameter of the pipe — not the nominal bore — ensuring a close, gap-free fit that maximizes thermal performance. Each pair is labeled with pipe size, insulation thickness, and section number for straightforward on-site identification.
Custom Large-Diameter Pipes
For pipes above 24″ up to 48″, sections are CNC-machined to order from calcium silicate board blanks. Multi-segment construction (three or four arc segments per layer) is used for very large diameters to keep individual piece weight manageable during installation. Provide your pipe OD and insulation thickness; we calculate the optimal segment geometry. Lead time for custom large-diameter sections is 20–25 working days.
Section Length & Packaging
Standard section length is 600mm (approx. 24″), matching common pipe support spacing. Custom lengths of 300mm, 500mm, and 1000mm are available. Sections are supplied as matched pairs, packed in cartons by pipe size and thickness. Each carton is labeled with contents for efficient inventory management on site. Fumigated ISPM 15 pallets for international shipping.
2. Half-Shell & Section Dimensions
The table below shows standard stocked combinations of pipe diameter and insulation thickness. Sections for non-standard combinations are produced to order.
| Nominal Pipe Size | Pipe OD (mm) | Available Thicknesses (mm) | Section Length (mm) | Typical Application |
|---|---|---|---|---|
| 1/2″ (DN15) | 21.3 | 25, 30, 40, 50 | 600 | Small-bore steam tracing, condensate |
| 1″ (DN25) | 33.7 | 25, 30, 40, 50, 60 | 600 | Steam distribution, instrument lines |
| 2″ (DN50) | 60.3 | 30, 40, 50, 60, 75 | 600 | Process steam, hot water, thermal oil |
| 4″ (DN100) | 114.3 | 40, 50, 60, 75, 80, 100 | 600 | Main steam headers, boiler feed |
| 6″ (DN150) | 168.3 | 40, 50, 60, 75, 80, 100 | 600 | High-pressure steam, refinery lines |
| 8″ (DN200) | 219.1 | 50, 60, 75, 80, 100 | 600 | Steam mains, process gas ducts |
| 12″ (DN300) | 323.9 | 50, 60, 75, 80, 100 | 600 | Power plant steam, turbine crossovers |
| 16″ (DN400) | 406.4 | 60, 75, 80, 100 | 600 | Refinery transfer lines, hot oil |
| 20″ (DN500) | 508.0 | 60, 75, 80, 100 | 600 | Petrochemical process, reformer outlet |
| 24″ (DN600) | 610.0 | 75, 80, 100 | 600 | Furnace transfer lines, flare headers |
Pipe OD values are for standard schedule (SCH 40/STD) carbon steel pipe. For stainless steel, alloy steel, or non-standard schedules, provide actual OD and we match the section bore. Custom thicknesses and non-standard pipe diameters above 24″ are produced to order.
3. Technical Specifications — ASTM C533 Type I & II
Mingfa calcium silicate pipe insulation is manufactured to ASTM C533, the standard specification for calcium silicate block and pipe thermal insulation. Both Type I (650°C) and Type II (927°C) grades are available, with Type I being the standard for most process piping applications.
| Property | Type I (650°C) | Type II (927°C) | Test Method |
|---|---|---|---|
| Max Service Temp | 650°C | 927°C | ASTM C533 |
| Bulk Density | 170–250 kg/m³ | 230–270 kg/m³ | ASTM C302 |
| Compressive Strength | ≥2.0 MPa | ≥2.5 MPa | ASTM C165 |
| Flexural Strength | ≥0.8 MPa | ≥1.0 MPa | ASTM C203 |
| Thermal Cond. @ 100°C | ≤0.058 W/m·K | ≤0.062 W/m·K | ASTM C518 |
| Thermal Cond. @ 200°C | ≤0.068 W/m·K | ≤0.075 W/m·K | ASTM C518 |
| Thermal Cond. @ 400°C | ≤0.088 W/m·K | ≤0.095 W/m·K | ASTM C518 |
| Linear Shrinkage (24 h) | ≤1.5% at 650°C | ≤1.5% at 927°C | ASTM C356 |
| Moisture Content | ≤4% | ≤4% | ASTM C533 |
| Chloride Content | ≤25 ppm | ≤25 ppm | ASTM C871 |
| Flame Spread / Smoke | 0 / 0 | 0 / 0 | ASTM E84 |
| Fire Classification | A1 | A1 | EN 13501-1 |
Chloride content is controlled to ≤25 ppm for stainless steel pipe applications, where chloride-induced stress corrosion cracking (SCC) is a concern. This meets the requirements of ASTM C795 for thermal insulation for use in contact with austenitic stainless steel. Standard documentation includes chloride test results with every shipment for stainless steel applications.
4. Installation Methods
Proper installation ensures the full thermal performance of the half-shell pipe cover is realized over the service life of the system. The following methods are standard practice for calcium silicate pipe sections.
SS Band Fixing
Half-shells are secured to the pipe using stainless steel (304 or 316 grade) bands at minimum two bands per 600mm section length. Bands are typically 12.7mm (1/2″) wide, tightened with a banding tool to a firm but not crushing tension. For pipes above 12″ diameter, three bands per section are recommended. For outdoor installations, 316-grade bands resist pitting corrosion in marine and coastal environments.
Aluminum Weather Jacket
For outdoor and weather-exposed installations, the insulated pipe is clad with aluminum sheet jacketing (typically 0.5–0.8mm / 24–20 gauge, alloy 3003 or 3105). Jacket sheets are formed to diameter with a 50mm circumferential overlap, secured with aluminum or stainless banding at 300mm centers. Longitudinal seams should be positioned at the 4 o'clock or 8 o'clock position to prevent water ingress. For steam lines, vapor barrier mastic is applied over the calcium silicate before jacketing.
Butt Joint Sealing
End joints between adjacent sections are butted tightly together. A 1–2mm gap is acceptable; larger gaps should be filled with loose calcium silicate insulation fragments (not compressible mineral wool, which can create a thermal short circuit). For multi-layer insulation, circumferential and longitudinal joints must be staggered by at least 150mm between layers. In outdoor applications, a self-adhesive aluminum foil tape (50mm wide) is applied over each butt joint before the weather jacket, acting as a secondary vapor seal.
5. Applications — Steam, Hot Oil, Process Lines
Calcium silicate pipe insulation is specified for industrial piping systems where operating temperature exceeds 250°C — above the practical service limit of mineral wool and fiberglass. The following are the most common application categories.
Steam Systems
High-pressure steam distribution (up to 650°C superheated steam in power plants). Main steam, cold reheat, hot reheat, auxiliary steam, and extraction steam piping. Calcium silicate half-shells are the standard insulation for steam lines above 350°C because they do not compact, sag, or lose thickness under thermal cycling — problems that plague mineral wool pipe insulation at elevated temperatures.
Hot Oil & Heat Transfer Fluid
Thermal oil circuits in chemical plants, asphalt terminals, and food processing facilities typically operate at 250–350°C. Calcium silicate pipe insulation provides consistent thermal performance with zero organic binder content — meaning no smoke, no odor, and no degradation if the system overheats. Non-combustible per EN 13501-1 A1, so it cannot contribute to a fluid fire.
Petrochemical & Refinery
Fired heater transfer lines, distillation column feed lines, reformer outlet piping, and flare headers. In refinery environments, the A1 fire classification is essential: in a hydrocarbon fire scenario, calcium silicate does not contribute fuel load or emit toxic smoke. Chloride content is controlled for stainless steel lines per NACE SP0198 corrosion under insulation (CUI) mitigation guidelines.
Marine & Offshore
Engine exhaust insulation, steam service on FPSO and platform vessels, LNG carrier piping. Lightweight (170–250 kg/m³) compared to traditional calcium silicate with good mechanical integrity under vibration. Water-repellent treated versions are available for marine environments. Meets IMO FTP Code requirements for non-combustible materials on vessels subject to SOLAS.
Power Generation
Boiler steam piping, turbine bypass lines, feedwater heater shells, HRSG (heat recovery steam generator) ductwork, and balance-of-plant piping. Calcium silicate's dimensional stability under thermal cycling (start-up/shut-down) prevents joints from opening over time — a leading cause of degraded insulation performance in cyclic power plant service.
Process & Chemical
Reactor jacket piping, distillation overheads, crystallizer circuits, and molten sulfur lines. In chemical environments, calcium silicate is resistant to most process chemicals (pH 7–11) but is attacked by hydrofluoric acid and strong alkalis. For aggressive chemical environments, contact our technical team for compatibility assessment.
6. Custom Pipe Fittings
Piping systems include more than straight runs. Mingfa produces CNC-machined calcium silicate pipe insulation fittings for all common pipe components. Fittings are supplied as multi-piece assemblies keyed to fit the specific component.
Elbows (90° & 45°)
Two-piece mitred sections for short-radius and long-radius elbows. Cut to match the elbow's centreline radius. Supplied as matched halves for each elbow.
Tees & Branches
Equal and reducing tees, fabricated as three-piece assemblies with the branch piece coping into the main run section. Marked for on-site assembly sequence.
Valves & Flanges
Split-box insulation covers for gate, globe, and ball valves. Flange pair covers with clearance for bolt access. Removable for inspection and maintenance.
Reducers & Expanders
Concentric and eccentric reducer insulation sections, tapered to match the reducer angle. Supplied in two halves for straightforward installation over the reducer fitting.
To order custom fittings, provide a pipe isometric drawing or fitting schedule listing the component type, pipe diameter, insulation thickness, and quantity. Standard lead time for fittings is 20–25 working days.
7. Ordering Information
To receive an accurate quotation for calcium silicate pipe insulation, please provide the following in your inquiry.
Pipe Diameter
Nominal pipe size (NPS inches or DN mm) and actual outside diameter. Include pipe schedule if non-standard wall thickness affects OD. For insulated pipes, indicate the outer diameter of the pipe including any factory-applied coating or primer.
Thickness & Length
Insulation thickness in mm. Total linear meters (or feet) of straight pipe for each diameter/thickness combination. Include a bill of materials or pipe list if available for accurate quantity take-off.
Operating Temperature
Maximum continuous operating temperature. This determines whether Type I (650°C) or Type II (927°C) material is appropriate. Include any temperature cycling information for fatigue life assessment of the insulation system.
Minimum Order Quantity: 1 carton per size/thickness combination. Lead time: 15–20 working days for standard pipe sections, 20–25 working days for custom diameters and fittings. Shipping: FOB Qingdao, CIF to your port. Payment: T/T (30% advance, 70% before shipment) or L/C at sight. Documentation: Commercial invoice, packing list, bill of lading, certificate of origin (Form E/F for preferential tariffs), and batch test certificate included with every shipment.