Field guide chpt 4 - 5

Question 1

The corrosion investigator’s first job on-site is to

Answer 1

protect all the evidence

Question 2

The corrosion investigator’s second job on-sit is to

Answer 2

collect all evidence

Question 3

The presence of water can be confirmed in a sample by using

Answer 3

Hydrion paper

Question 4

Which gas analysis test cannot be collected with a stain tube?

Answer 4

pressure

Question 5

A procedure that penetrates and preserves the scale , corrosion product, microbes, and deposits that are present on an internally corroded pipe is

Answer 5

Embedment

Question 6

The temperature of liquid samples is measured in the field using a common _______ _______ or with an _____ ______ .

Answer 6

Clean thermometer

electronic thermometer

Question 7

The pH of aqueous samples is measured using a ______ _____ or ______ ______.

Answer 7

pH meter

pH paper

Question 8

These samples must be taken where there are differences in color, texture, density or composition of material in the pipe. These samples must be taken carefully to avoid damaging other corrosion evidence and must be carefully identified in terms of physical location.

Answer 8

Pipe sampling

Question 9

These samples are normally collected in stainless steel sample bottles or Tedlar bags. Stain tubes can sometimes be used to replace some samplings.

Answer 9

Gas Sampling

Question 10

Collect at least 500ml in two 250ml sample containers at the site of the cut if possible. Samples should be filled to the top to exclude air and capped. Samples should be kept in a cool dark place if possible.

Answer 10

Liquid sampling

Question 11

This sample should be cut using a portable band saw or wheel-type cutter to prevent torch cutting debris from entering the sample. this sample should be marked with relevant operating information such as flow direction, top, bottom, mile post, wheel count, etc.

Answer 11

Solid/Sludge sampling

Question 12

This method provides elemental compositional analysis of very thin (3nm) surface layers. It has better spatial resolution and sensitivity and is more quantitative than EDS. It is only appropriate for certain types of corrosion related samples such as selective corrosion and grain boundaries or other metallurgical features.

Answer 12

(AES) Auger Electron Spectroscopy

Question 13

These two methods are used with microscopes to examine small areas or features. Both methods usually allow mapping of the surface and are used for bulk sample analysis.

Answer 13

FTIR and Raman Spectroscopy

FTIR (Fourier transform infrared spectroscopy)

Question 14

This is a common technique used to identify crystalline phases in unknown materials. These crystalline phases are described as compounds rather than elements which is beneficial in understanding corrosion reactions. It requires only a few grams of sample and non-crystalline components can also be identified.

Answer 14

(XRD) X-Ray Diffraction

Question 15

A long established technique used to identify nearly 70 elements in liquid and solid samples down to parts per billion. This technique is used to identify metallic elements found in corrosion products that couldn’t be found using ion chromatography.

Answer 15

Atomic Absorption

Question 16

This method is used to look for corrosion inhibitors, biocides, methanol, glycol, and other organic materials but the investigator must have some idea of the organic material for which they are searching.

Answer 16

Gas or Liquid Chromatography

Question 17

these 2 methods can quantitatively identify over 70 elements in liquids, solids, and particulates. They provide shorter analysis times than AAS. Sample sizes of 100ml for liquids and 1 gram for solids are common.

Answer 17

DCP/ICP

direct current plasma / inductively coupled plasma

Question 18

This procedure uses liquid chemistry data to calculate values which are simply indications as to the propensity for deposition or dissolution of calcareous deposits.

Answer 18

Scaling Index

Question 19

This term describes laboratory analysis techniques such as gravimetry, titrimetry, and numerous separation methods. It is time consuming and the methods vary widely with sample type and composition and often require some educated guesswork to describe a non homogeneous sample.

Answer 19

Wet Chemistry

Question 20

This is a popular method for determining the concentrations of ionic species in aqueous samples. Typical results would identify sulfate, sulfite, nitrate, nitrite, phosphate, chloride, bromide, and fluoride ions. It can also identify the organic acid present in an aqueous ample. Results are reported in either ppm or mg/L.

Answer 20

ION Chromatography

Question 21

This pair of tests are some of the most popular techniques used for examining and analyzing elemental surface of corrosion-related samples. One test provides a high-resolution view of the corroded surface and corrosion products while the other provides elemental chemical composition data of both discrete particles and larger areas. This combination analysis is an investigative procedure that the corrosion investigator should directly observe and participate in when ever possible.

Answer 21

SEM/EDS
Scanning Electron Microscope /
Energy Dispersive Spectroscopy

Question 22

This technique is used more frequently in the study of microorganisms than of corrosion. Histological embedments of corrosion products and bio films can be used in this process by taking thin sections from the embedment. The primary limitation of this procedure is the length of time required for sample preparation and the cost.

Answer 22

TEM

Transmission Electron Microscopy

Question 23

This method is like Auger as another method that analyzes atomic surface layers for elemental compositions. It is more sensitive and has better spatial resolution than EDS. It is sensitive to trace elements in the parts per million and parts per billion range. It can characterize both inorganic and organic surface materials. It is used for compositional depth profiling, bulk impurity analysis, and examination of specific metallurgical features.

Answer 23

SIMS

Secondary Ion Mass Spectroscopy