Pressure Measurement

Pressure Measurement Devices

Pressure Scales

Bourdon Tube

Pressure

Motion

CrossSection

Bourdon Tube Gauge

Bourdon Tubes

Bellows

Pressure

Motion

FlexibleBellows

Bellows Gauges

Diaphragm

Pressure

Motion

FlexibleMembrane

Diaphragm Differential Gauge

Switch

Capsule 1

Pressure

Motion

FlexibleMembranes

continuousseam

seam

Capsule 2

Differential Pressure Cell

Typical Pressure Transmitter

Pressure Transmitter Installation

Strain Gauge

ForceForceAREA AREA AREA

Resistance Ω Increases

Cross Sectional Area Decreases

Length Increases

Strain Gauge DP Cell

Capacitance Cells

Operating Environment

! Vibration! Temperature! Vapour Content

Failures and Abnormalities

! Over-pressure! Blocked sensing lines! Leaking sensing lines! Loss of electrical power

For you to do

! Read pp 8-17! Answer questions pp. 81-82, #1-5