Expanded perlite at 200 °C — heat-loss table

λ = 0.066 W/m·K at mean temperature ((200+20)/2 = 110 °C, from the published curve). Pipe losses per metre, four thicknesses, savings vs bare.

Pipe	30 mm W/m	50 mm W/m	80 mm W/m	100 mm W/m	BARE W/m	Surface @50 mm	Saving €/m·yr @50 mm	t CO2/m·yr
DN25	64	51	41	37	189	32 °C	€67	0.25
DN50	94	71	55	50	341	34 °C	€132	0.48
DN80	124	91	69	61	503	35 °C	€201	0.74
DN100	151	109	81	71	646	36 °C	€262	0.96
DN150	207	145	106	92	952	37 °C	€393	1.44
DN200	259	180	129	110	1,239	38 °C	€517	1.89
DN300	367	250	175	148	1,832	39 °C	€772	2.82

Assumptions: 20 °C ambient, still air (h=10 W/m²·K combined), €0.05/kWh fuel, 8000 h/yr, 82% efficiency, 0.183 kg CO2e/kWh (DESNZ 2024). Flat surfaces at this duty: bare 1,800 W/m² → 211 W/m² at 50 mm (≈€775/m²·yr saved). Method: ASTM C680 simplified — methodology. Your exact case: free calculator.

Context

All materials at 200 °C

Material	λ W/m·K	Loss W/m	Surface	Saving €/m·yr	t CO2/m·yr
Stone wool (mineral wool)	0.048	80	32 °C	€276	1.0
Glass wool	0.046	77	31 °C	€278	1.0
Ceramic fibre (RCF / AES blanket)	0.060	99	35 °C	€267	1.0
Aerogel blanket	0.026	45	27 °C	€294	1.1
Calcium silicate	0.063	104	35 °C	€265	1.0
Expanded perlite	0.066	109	36 °C	€262	1.0
Cellular glass	0.054	89	33 °C	€272	1.0
Microporous (fumed-silica) panels	0.022	39	26 °C	€296	1.1
E-glass needle mat	0.046	78	32 °C	€277	1.0
Silica needle mat / fabric	0.055	91	34 °C	€271	1.0

DN100 pipe at 200 °C, 50 mm insulation, per metre of pipe; bare loss 646 W/m. λ at mean temperature; € and CO2 per metre·year at €0.05/kWh, 8000 h, 82% efficiency. Method: ASTM C680 simplified (h=10).

Material datasheet: Expanded perlite → · temperature class: by temperature →

FAQ

Questions on this topic

How much heat does a pipe at 200 °C lose with expanded perlite?

With 50 mm at 200 °C (λ=0.066 at mean): DN50 loses 71 W/m, DN100 109 W/m, DN200 180 W/m — vs 646 W/m bare for DN100. Full table on this page.

What surface temperature does expanded perlite give at 200 °C?

≈36 °C with 50 mm on DN100 (20 °C ambient, still air). Personnel-protection targets (≤45–60 °C) may need more thickness — see the 80/100 mm columns.