5: Defect Identification Flashcards
Vessels often contain both fluids and gases at the same time, what is it called where these meet? And what is it prone to?
The place where these meet is called the “liquid level” and can be especially prone to corrosion
Areas that have residual stress, such as the heat-affected zone in welds are more prone to what?
They can corrode quicker than adjacent parent or weld material
Weld areas, changes in thickness and areas of thermal difference are all prone to what?
Cracking
What’s another name for a mount ring?
Skirt
What is a major concern when inspecting tanks?
Corrosion. Though cracking and deformation (buckling) of plates does occur.
What does ERW stand for?
Electric Resistance Weld
What do ERWs add?
A point of potential stress and weakness - leading to corrosion or cracking
What allow pipes to change diameter?
Reducers
What allow pipes to change directions?
Elbow connectors (most commonly found in 90-degree and 45-degree angles)
How are pipes joined to other pipe sections or components such as pumps or valves?
With flanges that are often welded to the pipe that use bolts or other mechanical connections to connect them.
What are valves used for?
They direct the flow of the product running in the pipe and are required when product must be redirected, restricted or turbulent.
Common issues with valves include:
Pitting, erosion and buildup of solids on sealing surfaces that control the valve
What areas of the valve body should be inspected?
Sealing surfaces, moving parts, shafts (especially where they come in contact with other materials), and upstream/downstream of flow restrictions
Bent or necked fasteners (bolts) are signs of what?
Misuse or incorrect installation
What are snubbers used for?
Reduce vibration, pulses or surges that can cause unwanted movement (limit larger movements)
