Pipe heating duty and ΔT worksheet

Freeze protection, viscosity control and process temperature maintenance set different set points, loads and tolerance bands. Name the duty before anyone computes a watt.

Step 1 — Name the duty

Three questions about the line

Answer the three questions, then press the button.

What the answer changes

• Who owns the set point — the fluid’s freezing point, the pump curve, or the process engineer
• Duty cycle — off for most of the year, continuous with a cold restart load, or continuous
• How tight the control has to be — a band, a window, or a closed loop on a measured point

Step 2 — ΔT for the quotation

Target temperature minus design minimum ambient

Freeze protection uses the threshold temperature; viscosity control uses the target pumping temperature; process temperature maintenance uses the process temperature. The ambient figure is the design minimum, not today’s weather.

Enter both temperatures.

Step 3 — Convert a quoted wattage to W/m

Total watts divided by heated length

This converts a total wattage you already hold into a linear figure so two quotations can be compared on the same basis. It does not calculate heat loss and it does not size a heater.

Enter a wattage and a heated length.

What this worksheet does not do

It does not compute steady-state heat loss, and it does not set the wattage on your order. The wattage FlexBlanket is bound to is the calculated figure written into the quotation, derived from the pipe’s thermal load, the insulation already fitted and the design minimum ambient.

Send the duty, the target temperature and the design minimum ambient and we will name the construction class and the jacket that apply.