ABSTRACT

Corrosion Under Insulation (CUI) is widely acknowledged to be a critical issue facing plant operators in the oil, gas and chemical industries. CUI studies from a petrochemical facility have shown that 40-60% of pipe maintenance costs are due to CUI and approximately 10% of the total maintenance budget is spent repairing damage from CUI, mainly on pipes. The risk of corrosion under insulation is considered high in the temperature range 50 – 175°C (122 – 347°F) and extreme when in cyclic temperature service between −20 and 320°C (−4 – 608°F).

Periodic inspection remains the best way to prevent CUI failures but is costly and time consuming. Many failures might still not be captured even with a reliable inspection scheme and in this regard improvements which can reduce the degradation of the weathering barrier (the combination of insulation and jacketing) can be extremely beneficial. If CUI is not found in time, then the consequences can be severe for personnel, the environment and company reputation.

This paper will look at replacing conventional insulation used for energy conversation with an insulation coating system that does not require the use of jacketing to protect the insulation from moisture as described in IOGP S-738 as Class 1,2,4 and 9.

INTRODUCTION

Corrosion Under Insulation (CUI) is widely acknowledged to be a critical issue facing plant operators in the oil, gas and chemical industries. CUI studies from a petrochemical facility have shown that 40-60% of pipe maintenance costs are due to CUI and approximately 10% of the total maintenance budget is spent repairing damage from CUI, mainly on pipes. The risk of corrosion under insulation is considered high in the temperature range 50 – 175°C (122 – 347°F) and extreme when in cyclic temperature service between −20 and 320°C (−4 – 608°F).

Periodic inspection remains the best way to prevent CUI failures but is costly and time consuming. Many failures might still not be captured even with a reliable inspection scheme and in this regard improvements which can reduce the degradation of the weathering barrier (the combination of insulation and jacketing) can be extremely beneficial. If CUI is not found in time, then the consequences can be severe for personnel, the environment and company reputation.

Spray applied insulation coatings are normally used for personnel protection because the thermal conductivity of the dry films tends to be higher than conventional insulation materials as shown in table 1, and the film build is too low meaning that replacement of 20mm of conventional insulation would require at least 40 applications of current spray insulation coatings to match the thickness requirement In this paper we will show that a new insulation coating that has excellent thermal conductivity and high build capability offers a real alternative to conventional blanket and jacketing insulation solutions used today.

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