Insulation with Corrosion-Prevention Function for External Corrosion Inhibition: Japanese Patent No. 4201733 obtained
External corrosion of carbon steel under the insulation

There are cases where corrosion occurs on the carbon steel under the insulation when water penetrates into the insulation material. Especially in cases where the environment has a high salt content such as coastal areas or where the operating temperature is relatively low at 60 - 80°C, corrosion is likely to occur.

Current method for inhibit external corrosion
  1. 1.Protection of carbon steel by coating

    ‐Anticorrosive double coatingspecification
    →Deterioration due to rainwater or heat
  2. 2.Insulation absorption inhibition

    -Application of water- repellent insulation
    →Water repellency reduced at 250°C or more
  3. 3.Exterior material joint sealing

    -Application of silicon sealant
    →Joint cutting
These methods do not become long-term measures to inhibit corrosion!!
New measures to inhibit external corrosion (Keical Ace WIN)

"Keical Ace WIN" is a new type of insulation. The special anticorrosion pigment (calcium phosphate and Nitrous acid type hydrocalumite) is fixed inside calcium silicate (JIS A 9510 type 1-15 equivalent) which features lightweight, high strength and low thermal conductivity. 

The special anticorrosion pigment has the following properties:

Anticorrosive action of calcium phosphate

①When contact is made with water, the alkaline component is released to promote passivation.

Anticorrosive action of Nitrous acid type hydrocalumite (anion-exchange reaction)

②When contact is made with salt, salt is adsorbed into the Nitrous acid type hydrocalumite.
③At the same time, nitrous acid ion(corrosion inhibitor) is released to promote passivation.

In the highly-concentrated saline environment or when water is intruded, greater anticorrosive performance can be expected from "Keical Ace WIN" with the two properties of a special anticorrosion pigment, compared with conventional insulation.

従来保温材 WIN
Demonstration experiment
  • Feeding of hot water every 1.5 hrs. to hot-water pipe (3B) Pipe surface temperature: 90-95°C
  • Pipe corrosion state after disassembly

WIN has the effect of corrosion inhibition.

<Test Conditions>
Insulation 3" x 30mm with no exterior material
3% NaCl spray, 200 ml x twice per