Mechanical - valves 1

Valves

Mechanical - valves 2

Topics

! Regulating! Isolating! Back flow prevention! Pressure Relief

Mechanical - valves 3

Typical Actuator & Valve

Mechanical - valves 4

Diaphragm Actuator

Mechanical - valves 5

Positioner Indicator

Mechanical - valves 6

Valve Body

Mechanical - valves 7

Basic Valve ConstructionPlug Stem

Studs and Nuts

Packing Box

Valve Plug

Packing Rings

Packing Spring

Valve Seat

Valve Bonnet

Mechanical - valves 8

Valve Body

Mechanical - valves 9

Valve Characteristics

Mechanical - valves 10

Valve Plugs

Mechanical - valves 11

Valve Plugs

Mechanical - valves 12

Cage

Mechanical - valves 13

Cage too

Mechanical - valves 14

Removed Cage

Mechanical - valves 15

Air Input

Return Spring

Diaphragm

(a) Direct Acting (b) Reverse Acting

Air Input

Return Spring

Diaphragm

Stem

Yoke

Reverse & Direct Actuators

Mechanical - valves 16

Valve Plug Stem

Valve Plug

Valve Seat

(a) Direct Acting (b) Reverse Acting

Reverse & Direct Valves

Mechanical - valves 17

Failure Mode

Actuator Valve Body

Valve Action

Failure Mode

Direct Direct Air to Close

Fail Open

Reverse Reverse Air to Close

Fail Open

Direct Reverse Air to Open

Fail Closed

Reverse Direct Air to Open

Fail Closed

Mechanical - valves 18

Piston Actuators

Mechanical - valves 19

Piston Actuator

Mechanical - valves 20

Diaphragm Valve Operator

Mechanical - valves 21

Actuator and Positioner

Mechanical - valves 22

Actuator and Positioner

Mechanical - valves 23

Actuator Fluids

! Air! Oil (mineral and synthetic)! Clean! Moisture Free

Mechanical - valves 24

IsolatingValves

! Manual! Pneumatic! Electric Motor

Mechanical - valves 25

Manual Valve

Mechanical - valves 26

Handwheel

Mechanical - valves 28

Gate Valve

Mechanical - valves 29

Butterfly Valve

Mechanical - valves 30

Ball Valve

Mechanical - valves 31

Diaphragm Valve

Mechanical - valves 32

Checking Valve Position

! Visual Check! Position of handle! Indicator on valve

! Operational Checks! Situational Information

! temperatures, levels, pressures

! Direction of flow! Hearing and touch

Mechanical - valves 33

Manual Operating Valves

! Safety equipment! Watch for body mechanics

Mechanical - valves 34

Pneumatic

Valves

Isolating

Mechanical - valves 35

Cover Nut

Conduit Opening

CoilPlunger

Stop Washer

Centering Washer

Valve Stem

Valve Body

Valve Disc

Valve Seat

2 Way Solenoid Valve

Mechanical - valves 36

SolenoidValve

E

D

A/O

Air Supply100 kPa(g)

Vent to Atmosphere

3 Way Solenoid Valve

Mechanical - valves 37

Electric Valve Operator

Mechanical - valves 38

Electric Actuator

Mechanical - valves 39

Valve Limit Switches

Mechanical - valves 40

Electric Actuator

Mechanical - valves 41

Valve Limit Switches

Mechanical - valves 42

Limitorque Valve Actuator

Mechanical - valves 43

Limitorque Valve Guts

Mechanical - valves 44

Motor Gear Drive

Mechanical - valves 45

Worm Gear

Mechanical - valves 46

Limit Switch

Mechanical - valves 47

Torque Switch

Mechanical - valves 48

Electric Valve Operator Switches

! Limit! Torque! Speed

Mechanical - valves 49

Manual Operation

! Hand wheel is engaged with a handle! Disengages when motor starts

! Valve can be taken off seat by slack in gearing

Mechanical - valves 50

Backseating

! Some valves! Seat at top of valve to remove pressure

from packing

Mechanical - valves 51

Intergate Valve

Mechanical - valves 52

Backflow Prevention

Mechanical - valves 53

Check Valves

Mechanical - valves 54

Check Valve Body

Mechanical - valves 55

Check Valve Gate Open

Mechanical - valves 56

Check Valve Gate Closed

Mechanical - valves 57

Safety --- Relief

! Relief! Lift proportional to overpressure! Liquid service

! Safety! Open quickly and completely on overpressure! Generally for gases

! Safety Relief ! Good for liquid and gas service

Mechanical - valves 58

Safety/Relief Valves

! Lifting pressure! Capacity! Popping! Blowdown! Chatter! Flutter! Simmering

Mechanical - valves 59

Safety or Relief Valve

Mechanical - valves 60

Safety or Relief Valve

Mechanical - valves 61

Valve Gags

! Require TSSA approval! ASME Section III

requires CNSC approval! No-approval required for

testing

Mechanical - valves 62

Mechanical - valves 63

Steam Traps

Mechanical

Thermostatic

Thermodynamic

Mechanical - valves 64

Mechanical Steam Trap

Mechanical - valves 65

Thermodynamic Steam Trap

Mechanical - valves 66

Again

Mechanical - valves 67

Trap Operation

! Visual! Sound! Temperature

! Infrared measuring

Mechanical - valves 68

Trap Open