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A D V A N C E D

M A T E R I A L S

&

P R O C E S S E S |

S E P T E M B E R

2 0 1 6

2 1

I

n the chemical, oil and gas, fossil fuel,

and nuclear power industries, pipe

and equipment corrosion is a major

cause of leaks and other issues that can

lead to early replacements, unplanned

outages, and incidents potentially

resulting in plant and factory damage

and injury to workers. To learn more

about this topic,

Advanced Materi-

als & Processes

spoke with Brian Wil-

son, business development manager,

energy markets, portable analytical

instruments, for Thermo Fisher Scien-

tific, about the causes and dangers of

infrastructure corrosion and how por-

table analysis tools can help facilities

save time and improve safety.

Can you discuss the importance of

analyzing element concentrations in

industrial infrastructure?

Throughout the chemical, oil

and gas, fossil fuel, and nuclear power

industries, there is an increased focus

on measuring residual elements in the

carbon and microalloyed steels used

in piping and components. It is imper-

ative to understand the expected life

and performance of the infrastructure.

As carbon steel manufacturing has

become more dependent on recycled

metal scrap, residual element concen-

trations in materials have increased.

These can significantly impact mate-

rial properties—including corrosion

resistance—with regard to melting and

maintenance of piping and compo-

nents. We have seen elemental analysis

become increasingly important for both

installed and newly purchased indus-

trial framework and equipment.

Is the need for materials analysis

greater today than in the past?

Industrial infrastructure across the

country is aging, with many oil refining

and petrochemical sites using the same

pipe they did 30 or 40 years ago. As

piping and components age, the abil-

ity to verify their elemental makeup is

essential in order to prevent leaks and

ruptures that could adversely impact

worker safety and plant reliability. In

the past, metals analysis primarily

focused on heavy elements that made

up the largest proportion of the alloy

matrix. Today, we are learning more

about corrosion mechanisms and the

need to analyze residual, or trace ele-

ments, which require more sensitive

testing technology to measure. It is

critical that refineries and plants imple-

ment a material verification program

(MVP) proactively—before a costly fail-

ure occurs—as infrastructure ages.

What are the main causes of corro-

sion across the industrial sectors?

A number of variables cause

corrosion at industrial sites, mainly

stemming from sustained equipment

use and elevated levels of residual

elements. One cause, in particular, is

flow-accelerated corrosion. This occurs

when the protective oxide layer on the

inside surface of carbon and low alloy

steel pipe dissolves as iron oxides that

naturally form on the pipe’s exposed

surface are removed by hot water flow-

ing over it. Elevated levels of residual

elements such as chromium, copper,

and nickel can also cause corrosion in

hydrofluoric acid alkylation units, while

carbon steels with low silicon content

TECHNICAL SPOTLIGHT

USING ELEMENTAL ANALYSIS TO

MANAGE INDUSTRIAL CORROSION

As industrial infrastructure continues to age, the risk of corrosion-related

incidents becomes greater, increasing the need for detailed analysis of

residual elements in steel framework and equipment.

Thermo Scientific Niton XL5 XRF analyzer

inspects finished welds in steel piping.

can corrode at an accelerated rate when

exposed to hydrogen containing sulfur

compounds at elevated temperatures.

Using materials analysis technology,

technicians can measure the elemental

composition of piping and components

and detect the presence of alloying

elements (such as silicon, vanadium,

niobium, and titanium) that can reduce

the rate of deterioration, in addition to

residual elements that can contribute

to corrosion.

Several technologies are available

to analyze the elemental content

of metals. Which approach do

you recommend for industrial

infrastructure?

For metals analysis, materials

characterization is generally performed

using methods such as x-ray fluores-

cence (XRF), optical emission spec-

trometry (OES), and lab analysis. Over

the years, the materials characteri-