How much heat does a bare pipe lose?

A bare DN50 (2") steam line at 150 °C in 20 °C still air loses roughly 250 W per metre. Over 50 m plus four valves that is about 13 kW — around 100 MWh of fuel a year. Removable insulation cuts this by about 82%.

What insulation thickness do I need for a DN50 steam line at 150 °C?

50 mm of mineral wool (k≈0.055 W/m·K at ~85 °C mean) on a DN50 line at 150 °C reduces heat loss by roughly 82% and brings the surface to about 29 °C — touch-safe. Thicker insulation gives diminishing returns; the calculator shows the trade-off live.

How is insulation payback calculated?

Payback = installed insulation cost ÷ annual energy saved in money. Annual saving = heat saved (W) × operating hours ÷ system efficiency × energy price. Industrial removable insulation on hot lines typically pays back in 9–24 months.

Is this calculator ASTM C680 compliant?

Yes. It uses the ASTM C680 / ISO 12241 steady-state method for cylindrical (pipes, shells), flat (walls, tanks) and spherical (heads) geometries, with a combined outer surface coefficient. Results are survey-grade estimates; confirm critical numbers with a site survey.

What surface temperature is touch-safe?

Personnel-protection guidance (ASTM C1055, EN ISO 13732-1, OSHA) puts the burn-risk threshold around 60 °C / 140 °F. Inzonex modular insulation typically achieves ≤45 °C on hot equipment. The calculator flags whether the insulated surface is touch-safe.

How much CO₂ does insulating a steam line save?

Insulating a 50 m DN50 (2") steam line at 150 °C with removable mineral wool cuts heat loss by about 82% and avoids roughly 20 tonnes of CO₂ per year. Because the saving is on burner fuel it counts as a direct Scope 1 reduction and a measurable ISO 50001 energy-performance improvement; the calculator shows tonnes of CO₂ avoided per item and for the whole site.

Does it calculate touch-safe surface temperature for personnel protection?

Yes. It computes the insulated outer surface temperature and flags whether it is touch-safe. Personnel-protection limits (OSHA, EN ISO 13732-1, UL 2200) put the burn threshold near 60 °C / 140 °F; Inzonex modular insulation typically reaches ≤45 °C, turning a bare 150 °C burn hazard into a safe-to-touch surface.

How do I size insulation to prevent condensation on a cold pipe?

To stop condensation on a cold or chilled line, the insulation must keep the outer surface above the ambient air dew point. Work out the dew point from air temperature and relative humidity (the Magnus formula), then add enough thickness so the ASTM C680 surface temperature stays above it, plus a small margin. The calculator's Condensation control tab solves the required anti-condensation thickness directly — for example, air at 30 °C and 80% RH has a dew point near 26 °C, so a cold pipe needs roughly 20–30 mm of closed-cell insulation with a vapour barrier to stay dry and avoid corrosion under insulation.

How long until water freezes in an insulated pipe?

Insulation slows but does not permanently prevent freezing of stagnant water — it only buys time. The time for still water to cool from its starting temperature to 0 °C follows lumped-capacitance cooling: t = R·C·ln((T₀−Tₐ)/(0−Tₐ)), where R is the insulation-plus-film resistance and C is the water's heat capacity per metre. Insulating a small line typically multiplies the bare time-to-freeze several-fold; for indefinite protection use electric heat tracing under the insulation. The Freeze protection tab returns the time-to-freeze at any thickness.

How much heat does an uninsulated valve or flange lose?

A bare valve or flange loses about as much heat as 0.5–1 m of bare pipe — roughly 150 W each on a DN50 line at 150 °C. A few bare valves can equal the loss of a whole insulated run, so removable valve and flange insulation pays back fastest. The calculator adds each valve as an equivalent bare-pipe length.

How do I calculate heat loss from a tank or vessel?

Tanks and vessels are modelled by surface area — flat walls as a flat plate and dished heads as a sphere, per ASTM C680. A bare 80 °C tank wall in 20 °C air loses about 600 W/m² (hₒ·ΔT); 50 mm of insulation cuts that by roughly 85%. Enter the surface area, temperature and insulation thickness on the flat-surface or vessel tab.

What units does the heat-loss calculator use — W, kW, BTU/hr?

Results read in W and W/m, total kW, and annual kWh and MWh, plus money saved and CO₂ avoided. For US units, 1 W/m is about 1.04 BTU/hr·ft and 1 kW is about 3,412 BTU/hr. Energy cost is shown in your own currency (EUR, USD, GBP) at the price you enter.

What is the difference between NPS and DN pipe sizing?

NPS (½"–16") and DN (DN15–DN400) are two labels for the same outer pipe diameter — DN50 is 2", DN100 is 4". Pick whichever your specification uses; the heat-loss result is identical. The sizing standard is switchable at the top of the calculator.

Can you calculate heat loss for a whole plant or a spreadsheet of equipment?

Yes — add multiple items across pipes, flat surfaces, heat exchangers and vessels into one project for a whole-site total of energy, cost and CO₂. For a full equipment list and an exact quote, send your data to Inzonex for a heat-loss report.

Can insulation savings count toward ESOS, SECR or CSRD reporting?

Yes. Insulating hot equipment cuts burner fuel, so the saving is a direct Scope 1 reduction measured in tCO₂e — exactly the energy-efficiency action documented in UK ESOS audits, disclosed under SECR and the EU CSRD, and credited within ISO 50001. The calculator outputs tCO₂e avoided per item and per site for your carbon accounting and net-zero reporting.

Is insulation an EHS / personnel-protection measure?

Yes. A bare 150 °C surface is a burn hazard; personnel-protection limits (OSHA, EN ISO 13732-1, ASTM C1055, UL 2200) put the threshold near 60 °C. Inzonex modular insulation typically brings the surface to ≤45 °C — touch-safe — so it is both an EHS/burn-risk control and an energy measure. The calculator flags whether each insulated surface is touch-safe.

熱損失 & 断熱ROI 計算ツール

本ツールはASTM C680およびISO 12241の定常熱伝達法 — 業界標準の3E Plusツールと同じ基礎 — を着脱可能なInzonex断熱に適用しています。以下：物理、回収期間を左右する数値、そして裸の設備が静かに費用を浪費している箇所。

裸の配管はどれだけ熱を失いますか？

裸の金属配管表面はほぼプロセス温度にあるため、その損失は外側の境膜のみで決まります：Q/L = hₒ·π·D·ΔT。総合係数 hₒ≈10 W/m²·K のとき、20 °Cの空気中で150 °CのDN50（2″）配管は約250 W/mを失います。

50 mmの断熱を加えると伝導が支配的になります：Q/L = ΔT / [ ln(r₂/r₁)/(2πk) + 1/(hₒ·π·D₂) ]。損失は約43 W/mまで低下 — ≈82%の削減です。

バルブ & フランジはどれだけ熱を失いますか？

断熱されていないバルブやフランジは、裸配管0.5～1 m分のように放熱します。ライン上のわずかな裸バルブだけで、断熱済み区間全体の損失に匹敵することもあります。形状が扱いにくいため通常は裸のまま放置され — だからこそ着脱可能断熱がここで最も早く回収できます。

本ツールは各バルブを等価な裸配管長として加算するため、その本当のコストが分かります。

断熱後の表面温度はどのくらいで触れても安全ですか？

やけどリスクの指針（ASTM C1055、EN ISO 13732-1、OSHA）は約60 °C / 140 °Fを超える表面を警告します。裸の150 °C配管は重大なやけど危険です。50 mmの断熱で表面は約29 °C — 触れても安全 — になり、Inzonexモジュール断熱は通常≤45 °Cを目標とします。

結果パネルは、断熱後の表面が触れても安全かどうかを表示します。

ワット単位の熱損失はどのように回収期間になりますか？

年間削減 = 削減熱量 × 運転時間 ÷ システム効率 × エネルギー価格。バルブ付きの断熱DN50区間1本で年間約€7,010と年間約20 t CO₂を削減でき、約11か月で回収します。

プラント全体では数値が急速に積み上がります — プロジェクトに追加でサイト全体を合計してください。

配管・設備の熱損失計算ツール

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