Rock Wool Pipe Insulation That Actually Holds Up on Real Jobs (2025 Update)

I’ve been doing rock wool pipe for 12 years. The question I get asked the most is still:

“Can rock wool really last 25-30 years on a hot steam line in the desert or a freezing cold store?”

Short answer: Yes — but only if you pick the right density and don’t fall for the cheap rubbish.

The Only Two Densities That Matter in 2025

100-120 kg/m³ → cold & acoustic lines, air-con, chilled water

140-180 kg/m³ → hot lines ≥120 °C, steam, refinery, power plant

Anything below 90 kg/m³ is basically rubbish — it sags in 2-3 years.

Real Numbers from Jobs We Supplied This Year

Sinopec Zhenhai Refinery (Ningbo) – 168 °C steam line 150 kg/m³ rock wool pipe + 0.4 mm aluminum foil After 18 months: surface temp drop from 135 °C → 42 °C, heat loss cut 64%, zero sagging.

Dubai 52-storey hotel – HVAC chilled water 120 kg/m³ rock wool + white PPGI jacket Condensation completely gone, noise in rooms dropped 11 dB, client now specifying it on all new towers.

German Passivhaus school project – heating pipes in slab 100 kg/m³ rock wool pipe shell Total thickness only 50 mm but still hits U < 0.18 W/m²·K for the whole floor assembly.

-35 °C cold store in Kazakhstan 180 kg/m³ rock wool + anti-abrasion coating Forklifts run over the pipes daily — 4 years, zero compression set.

The 3 Mistakes That Kill Rock Wool Pipes

Using 80 kg/m³ on anything over 80 °C → sags like spaghetti in 18 months

Skipping the anti-dust oil → workers itch like hell, fibers everywhere

Wrong jacket overlap → condensation creeps in at the seams

2025 Price Reality Check (FOB Tianjin)

100-120 kg/m³, Alu foil jacket: USD 2.8-3.4 per meter (DN100, 50 mm thick)

150 kg/m³, Alu foil: USD 4.1-4.6 per meter

180 kg/m³, anti-abrasion coating: USD 5.9-6.8 per meter

Still 30-40% cheaper than Armacell or K-Flex rubber on hot lines when you count 25-year life.

Want a free 1-meter sample pipe (any size up to DN200) to test compression and fire rating yourself?

Just tell me the temperature and diameter — I’ll send it this week, you only pay DHL (~USD 65).

Ruibin An

Hebei Woqin Trading Co., Ltd.

WhatsApp: +86 13933929092

12 years rock wool pipe & aerogel — only real samples.