1. ME444 ENGINEERING PIPING SYSTEM DESIGN
CHAPTER 1: INTRODUCTION

2. TENTATIVE SCHEDULE
BEFORE MIDTERM: THEORY OF FLOW IN PIPE, PIPE SIZING, PIPING MATERIALS, PUMP SELECTION
AFTER MIDTERM: DESIGN OF VARIOUS PIPING SYSTEMS FOR BUILDINGS AND INDUSTRIES
Book:

3. CONTENTS INTRODUCTION STANDARDS BASIC UNITS BASIC FLOW IN PIPE
QUICK LOOK AT PIPE DRAWINGS

4. 1. INTRODUCTION PIPING SYSTEMS EXIST IN EVERY ENGINEERING APPLICATION.
APPLICATIONS:
PLUMBING, FIRE PROTECTION,
PROCESS, AIR-CONDITIONING,
REFRIGERATION, VENTILATION,
COMPRESSED GAS, STEAM
FUNCTION:
TRANSMIT FLUID AT A PREFERED RATE TO THE DESTINATIONS WITH PREFERRED PROPERTIES
(I.E. PRESSURE, TEMPERATURE)
SESSION 1 MAIN REFERENCE: PUMPING STATION DESIGN

6. DESIGN CONCEPT
SOURCE
PIPING SYSTEM
END USERS

7. PIPING SYSTEM DESIGN END USERS’ REQUIREMENTS SOURCE PIPING SYSTEM PIPE
PRESSURE
TEMPERATURE …
FLOW
PRESSURE
TEMPERATURE …
PIPING SYSTEM
PIPE
MATERIAL
THICKNESS
PATHS
SIZES
PUMP
MATERIAL
TYPE
SIZE
VALVE
& ACC.

8. 2. STANDARDS

9. ASME STANDARDS

10. STANDARDS

11. STANDARDS

12. STANDARDS British Standard Deutsches Institut für Normung
Japanese Industrial Standard
Old mark
(expired)

13. 3. BASIC UNITS PIPE SIZE: INCHES, mm. PIPE LENGTH: FEET, METRES
VOLUME: CU.M., CU.FT., LITRES, GALLONS
FLOWRATE: GPM, CU.M./H, LPS, LPM, CFM
PRESSURE: PSI, BAR, m.WG., KG/CM2
POWER: KW, HP
STUDENTS MUST HAVE THE CONVERSION FACTORS

14. 7 basic quantities

15. Basic conversion
Length
Mass

16. Temperature

17. Area
Length
Mass

18. Volume

19. Volume Flowrate

20. Velocity

21. Pressure

22. Energy

23. Heat Flowrate and Power

24. Viscosity
ความหนืดสัมบูรณ์

25. Viscosity
ความหนืดเชิงจลนศาสตร์

26. Water Properties

27. Pguage = Pabsolute - Patm
GUAGE PRESSURE
Pguage = Pabsolute - Patm
Pguage is obtained from pressure measuring device.

28. Atmospheric pressure
Patm varies with altitude

29. Pressure at sea level At sea level Patm = 101.3 kPa P = rgh
Water can be drawn upto
h = Patm/rwaterg = ?? m
Patm

30. Pressure and elevation
In theory 1 barg of pressure can drive water up 10.2 m with zero flow.
Municipal Water Authority (MWA) attempt to deliver water at 2 barg.
2 barg = 20.4 m.WG.  = 6 Floors !!
In practical situations, pressure drops in main and branch pipes,
water hardly reach 2nd floor, so people use pump.

31. It’s illegal to pump water from city main

32. 4. BASIC FLOW IN PIPE

33. Flow Pattern
LAMINAR or TURBULENCE ?
Re < 2000
Re > 10000

34. REYNOLDS NUMBER Inertia vs. Viscous Effect
WATER FLOW AT 1.2 m/s IN A ½” PIPE
=TURBULENT

35. LOSS
MAJOR LOSS: LOSS IN PIPE
MINOR LOSS: LOSS IN FITTINGS AND VALVES

36. LOSS IN PIPE
LOSS IN PIPE CAUSED BY FRICTION BETWEEN FLUID AND PIPE SURFACE.
FRICTION CAN BE RELATED TO SHEAR STRESS. PA PB A B

37. VELOCITY AND LOSS A B LOSS IN PIPE VARIES WITH SQUARE
OF FLUID VELOCITY

38. FLOW AND LOSS FLUID VELOCITY IS RELATED TO THE FLOW RATE VIA PIPE SIZE
THUS..
C = f (DIAMETER, ROUGHNESS)

39. FRICTION LOSS CHART
DIAMETER
VELOCITY
DESIGN VELOCITY
1.2 TO 2.4 m/s

40. FRICTION LOSS EQUATION
HAZEN-WILLIAMS EQUATION (SI UNIT)
DARCY WEISBACH EQUATION
READING ASSIGNMENT: 3-2 FRICTION LOSS IN PIPE

41. MOODY DIAGRAM

42. MINOR LOSS LOSS IN FITTING: USE EQUIVALENT LENGTH
LOSS IN VALVE: USE CV OR KV
(DISCUSS LATER)

43. 5. QUICK LOOK AT PIPE DRAWINGS

44. NEXT SESSION
PIPING MATERIALS AND EQUIPMENTS
VALVES
PUMPS

45. HOMEWORK 1
Find a water valve (in a toilet, a kitchen or the backyard).
Measure inlet pipe size.
Measure the flow rate from a faucet at 25%, 50%, 75% and 100% opening (in lpm).
Find out the supply pressure (in m.WG.)