Where we do we go from here? (Where we do we go from here?)
Have we gotten lost? (Have we gotten lost?)

("Where Do We Go," by Mazare and RUNN, 2019)

 

THE PTOA PV* FLOWRATE FOCUS STUDY AREA BEGINS!

*Reminder: "PV" is shorthand for "Process Variable"

Ta-dah!

Brilliant PTOA Readers and Students ... meaning those who are reading the PTOA Segments in the intended, sequential order ... have completed the PTOA PV Temperature Focus Study Area and the PTOA PV Pressure Focus Study Area.

This PTOA Segment begins the PTOA PV Flowrate Focus Study Area.

The word "Flowrate" is a term that describes how fast a fluid flows through the pipes and the tubing found in processing facilities.

PTOA Readers and Students have a living-experience relationship with Temperature and changes in Temperature. Likewise, PTOA Readers and Students have encountered Flowrate on a daily basis.

For example ...The water Flowrate through a faucet determines how much time it will take to fill a pot with water, perhaps to boil pasta for spaghetti.  Ditto with respect to the time it takes for a bathtub to fill to the desired level,

The Flowrate of gasoline through the nozzle of a retail gas pump hose will determine how much time the person who is standing outside filling the car's gas tank will be freezing in the wintertime or sweltering in the summertime.

If the nearby gif loads, it will show a person who is too stressed to enjoy the Real-World visual lesson of observing what a 10 gallon per minute gasoline Flowrate looks like.

Since all PTOA Readers and Students have daily experiences with the concept of Flowrate, understanding the PV Flowrate will seem like a walk in the park on a sunny day compared to the brain work required to learn about the PV Pressure!

The above statement is not intended to diminish the importance of the PV Flowrate compared to the PV Pressure (or the PV Temperature).

PTOA Readers and Students are already aware that the Velocity component of a fluid's Flowrate and a Pressure Differential/Pressure Drop (ΔP) are inseparably linked ... no ΔP= no Flow ... which obviously means no Flowrate.

Regarding the PV Flowrate interface with the PV Temperature, PTOA Readers and Students already learned in PTOA Segment #65 that the PV Flowrate is a crucial factor with respect to Convective Heat Transfer

 

THE PTOA PV FLOWRATE FOCUS STUDY AREA INSTRUCTION PLAN

PV Flowrate Focus Studies naturally begin with the fundamentals. PTOA Readers and Students must become fluent with the jargon used for the various descriptions of gas and liquid Flowrate.

As PTOA Readers and Students learned in PTOA Segment #158, the Universe has informed Humankind that an increase in the magnitude of Flowrate is synonymous with an increased ΔP. So, guess what? A decrease in the magnitude of Flowrate is because of a decrease in ΔP.

The Fluid Properties that have already been featured in the PTOA will be examined more closely.  The concept and industrial applications of Vapor Pressure were featured in PTOA Segment #102, PTOA Segment #154, and PTOA Segment #162. Fluid Density, Specific Gravity, and Viscosity were also featured in PTOA Segment #162. These Fluid Properties are responsible for gas and liquid behaviors. Process Tech Operators who are interested in ultimately becoming Control Board Operators must understand the behaviors of gases and liquids.

Fluid Properties won't be the only content previously featured in the PTOA that will be more closely scrutinized in the PTOA PV Flowrate Focus Study Area.

The relationship between the PV Flowrate and the other main Process Variables ... Pressure, Temperature, and Level will come into focus.

As was mentioned above, the crucial relationship between the PV Flowrate and ΔP was featured in PTOA Segments #159 as the PV Pressure ↔ Fluid Velocity Swap and repackaged with the much haughtier label ... "The Venturi Effect" ... in PTOA Segment #207.

Which PTOA Readers and Students have noticed that increasing the Pressure Energy of a gas or liquid requires "Rotating Equipment" (e.g., Pumps, Compressors, and Turbines which all have many rotating parts and thus auxiliary lubrication systems) ...

and yet increasing, decreasing, or exchanging the PV Temperature requires "Stationary Equipment" (aka "Static Equipment") like Fired Heaters, Cooling Towers, Heat Exchangers, Boilers, Preheaters, Economizers, and Reactors?

PTOA Readers and Students will soon learn that the magnitude and velocity of the PV Flowrate are also determined by Stationary Equipment.

The Stationary Equipment associated with the PV Flowrate is called a Piping Network. The processing facility could not operate without all the low-tech, strung together hardware components that form the Piping Network.

In addition to determining the Flowrate of fluids, Piping Networks connect the Rotating Equipment associated with the PV Pressure and the Stationary Equipment associated with the PV Temperature and the PV Level together in the processing facility.

The components of a Piping Network include Joined Piping or Tubing Sections, Pipe Fittings and Pipe Auxiliaries, and Common and Special Valves. These low-tech hardware components distribute and deliver fluids to their intended location at the expected Flowrate.

PTOA Readers and Students are already familiar with one industrial Piping Network. The Cooling Water Supply and Return Headers and their respective distribution and collection pipes were the backbone of the Cooling Water Utility System featured in PTOA Segment #39.

Frankly, Joined Piping and Tubing Sections are the backbone of every Piping Network. A processing facility can easily have thousands of feet of pipes and tubes with a wide variance in sizes (aka ... pipe diameter). The thousands of feet of pipe and tube are made by "joining" together smaller sections of pipes and tubes during the construction phase of the processing facility. There are five typical methods for joining pipes and tubes together. The Engineering and Construction (E&C) firm that won the contract to build the process facility will determine which method to use for each pipe dedicated to a process flow service and each pipe dedicated to a utility service.

Pipe Fittings are incorporated into the joined pipe. Pipe Fittings change the physical direction of the flowing fluid, make it possible for a fluid to divide up into multiple process streams, change the size of the pipe diameter, and plug the end of a line.

Common Valves are also joined into the Piping Network. Common Valves are used to control the process stream Flowrate manually. There are dozens of types of Common Valves but only 4 classifications of Valve Functions. Some of the Common Valves that are totally open or totally closed can be modified with automatic actuators and thus activated remotely ...like by the Control Board Operator in the Control Room.

PTOA Readers and Students already know that the mere action of a fluid flowing through a pipe will result in that fluid losing some of its Pressure Energy. This "Pressure Drop" was featured in PTOA Segment #165 and is due to friction losses which occur when the flowing fluid interacts with the interior surface of the pipe.

Pressure Drop caused by friction losses also occurs when fluids flow through Pipe Fittings and Valves.

Valves have ISA symbols. The second letter in the PTOA Logo is the ISA representation for a (pneumatic) Gate Valve.

The PTOA PV Flowrate Focus Study Area extends the study of Valve hardware to include a pneumatic Final Control Valve (aka Final Control Element) used in a Flow Control Loop.

As was first mentioned way, way back in PTOA Segment #14, the ISA symbol for the Piping Network that connects Rotating and Stationary Equipment is just a thick black line. Minor process lines are represented as a thin black line.

In order to completely decode a Piping and Instrumentation Diagram (P&ID), the Piping Specification Sheet must be consulted. The Engineering and Construction firm that built the processing facility will provide their version of a Piping Specification Sheet. 

The PTOA PV Flowrate Focus Study Area concludes after focusing on the most popular PV Flowrate Flowmeters. Flowmeters sense/measure and transmit a signal that is thence finessed into a flow reading Humankind can understand.

Considering that a processing facility may be paying for water, sewer, and gas utilities and is presumably producing a gas, liquid, or solid product to wholesale paying customers ... how important do PTOA Readers and Students imagine the accuracy of the Flowmeters in these services need to be?

The Fluid Flowrate detection/measuring and transmission devices that are installed within the facility are likewise chosen for accuracy.

How else would a Control Board Operator know if the Feedstock Flowrate and Gas Flowrate to a Reactor are maintaining the target Gas-to-Liquid Ratio needed to favor the most profitable chemical reactions?

Without an accurate Flowrate measurement, how would the Control Board Operator know if the Boiler is providing the required Mass Flowrate of Steam needed for a Steam Turbine to drive an electricity Generator? Flowmeters are here, there, and everywhere in a processing facility.

Wow, that's a lot to learn about the PV Flowrate!

Here's the PTOA PV Flowrate Focus Study Area Instruction Plan:

 

THE PTOA PV FLOWRATE FOCUS STUDY AREA 
PART 1: PV FLOWRATE FUNDAMENTALS

• 

  10,000 cubic feet of a gas flowing through a pipe over a 5-minute time interval is equal to a PV Flowrate of 2000 Cubic Feet of gas per Minute (CFM).

  F is for Flowrate! The ISA symbols for the PV Flowrate

• All Industrial Piping is Rigid, not Flexible.
• The Definitions of Flowrate for Liquids and Gases
  • The Two Components of a Volumetric Flowrate (GPM, BPD, etc. and CFM, ACFM, SCFM, etc)
    • Correcting Volumetric Flowrate to Standard Conditions
    • Mass Flowrate (lbs/hr, kg/hr)

• • Laminar Flow and Turbulent Flow
  • Multiple Phase Flow

• • Fluid Characteristics That Predict Fluid Behavior
    • For Liquids and "Fluidized" Solids
    • For Gases

 

THE PTOA PV FLOWRATE FOCUS STUDY AREA
PART 2: THE RELATIONSHIP OF THE PV FLOWRATE WITH PV TEMPERATURE, PV PRESSURE, AND PV LEVEL 

• The PV Flowrate/PV Pressure Relationship (Review)

• • No ΔP=No Flow.
  • More ΔP= More Flowrate .... Less ΔP= Less Flowrate
  • The PV Flowrate-ΔPV Pressure Relationship Clarified
  • The PV Pressure ↔ Fluid Velocity Swap aka "The Venturi Effect."
  • Process Industry Examples that Use the PV Flowrate-ΔPV Pressure Relationship and the PV Pressure ↔ Fluid Velocity Swap Relationship.

 

• The PV Flowrate/PV Temperature Relationship
  • Review of Phase Changes ... Solids turning into Liquids and Liquids turning into Gases ... and vice versa.
  • PV Flowrate Changes caused by Temperature Increases impacting Fluid Properties.
  • PV Flowrate Changes caused by Temperature Decreases impacting Fluid Properties.
  • Process Industry Examples of PV Temperature Controlled by PV Flowrate.

 

• The PV Flowrate/PV Level Relationship
  • Gas and Liquid Process Lines: Feedstocks, Intermediate Products, and Final Products.
  • Maintaining Level with Steady-State Flowrates.
  • Unsteady-State/Emergency Situations Revealed by Unexpected Levels.

 

• The PV Flowrate/Process Operator Relationship

 

 

THE PTOA PV FLOWRATE FOCUS STUDY AREA
PART 3: PIPING NETWORK HARDWARE

The Purpose of Piping Networks: Fluid Movement and Delivery

• The Difference between Piping, Tubing, and Hoses
• Process versus Utility/Service Lines
• Not Metal Piping
• Metal Piping
  • Characteristics of Metals (Ferrous/Non-Ferrous, Ductility, Malleability)
  • Industrial Metallurgy Crash Course
  • Carbon Steel and Carbon Steel Alloys
  • Stainless Steel and Austenitic Stainless Steel
  • Nickel Alloy Steels (Monel, Inconel, Hastelloy)
  • 

    This strange piping is due to the thermal expansion of metal.

    Metallurgy Safety Awareness

    • Heat Treatment during Manufacturing and on site (PWHT)
    • Stress Corrosion Cracking (SCC) Awareness
    • Pipe Breaks and Thermal Expansion
  • Metal Pipe Manufacturing
    • Nominal Diameter
    • Inside/Inner Diameter
    • Outside/Outer Diameter
    • Pipe Schedules
  • Metal Piping Applications in Industry
  • Metal Pipe Auxiliaries (Pipe Racks, Hangers, Supports, etc.)

• Methods/Technology to Join Metal Pipes
  • 

    ISA Symbols for common pipe fittings.

    ISA Symbols for Pipe Joints

  • Welded Pipe Connections
  • Screwed (aka Threaded) Pipe Connections
  • Flanged Pipe Connections
    • Bolt Patterns
    • Blinds and Blind Lists
  • Brazing and Soldering Pipe Connections
  • Bell and Spigot Joint Pipe Connections

• Pipe Fittings
  • Pipe Fitting ISA Symbols
  • Pipe Fittings that change the physical direction of flow (Elbows, Return Bends)
  • Branching Fittings (Tees, Crosses, and Laterals)
  • Changing Line Diameter Fittings (Reducers, Expanders)
  • Capping and Plugging Lines
• Strainers, Filters, Traps

 

THE PTOA PV FLOWRATE FOCUS STUDY AREA
PART 4: COMMON VALVES, SPECIAL VALVES, AND THE FLOWRATE FINAL CONTROL ELEMENT/VALVE

• Common Valves
  • The four functions of Common Valves
    • Valves that Start and Stop Flow (Gate Valves, Ball Valves, Globe Valves, Plug Valves and Quick-Opening Versions)
    • Valves that Throttle and Regulate Flow (Globe Valves, Needle Valves, Butterfly Valves, Plug Valves)
    • Valves that Prevent Backflow (Check Valves)
    • Valves that Safely Manage and Get Rid of Excess Pressure (Pressure Relief Valves for Liquids, Pressure Safety Valves for Gases and Vapors)

• Special Task Valves
  • Pressure Reducing Valves
  • Back Pressure Valves
  • Rupture Disc Valves
  • Blow-Off/ Blow-Down Valves
  • On-Off Valves and their Actuators
    • Solenoids
    • Motorized Operated Valve
    • Hydraulic Operated Valve

• Automatic Flow Control: The Final Control Element Automatic Flow Control Valve
  • Pneumatically Actuated FCV/FCE
  • Electrically Actuated FCV/FCE
• Pressure Ratings for Piping, Fittings, and Valves

 

THE PTOA PV FLOWRATE FOCUS STUDY AREA
PART 5: DETECTION, MEASUREMENT, TRANSMISISON OF THE PV FLOWRATE

• 

  Head Type Measuring Devices with an intentional restriction that makes it possible to infer a Flowrate from a Differential Pressure.

  Flowrate Measurement Jargon/Classifications

  • Direct and Indirect Flow Sensing and Measurement
  • Instantaneous Flowrate versus Averaged Flowrate and Totalized Flowrate (aka Accumulated) Flowrate)
  • Direct Flow Measurement versus Indirect Flow Measurement
  • Actual versus Sensed/Measured Flowrates aka Correcting Measured Flowrate to Actual Conditions
    • For Liquids
    • For Gases
• Primary Flow Devices Detect/Measure Flowrate
  • Primary Flow Devices Defined
    • Head Type Devices that Don't Restrict Flow ... The Pitot Tube
    • Head Type Devices that Restrict Flow (Orifice Plates, Nozzles, Venturi Tubes)
    • Square Root Extraction
    • Installation Considerations
• 

  "Smart" Transmitters do the math, then send a 4-20 mA signal that represents a Flowrate. "Smart" Transmitters have many benefits over much slower, maintenance needy Pneumatic Transmitters.

  Secondary Flow Devices Defined

  • Manometers
  • Bellows Meter
  • Pneumatic Delta P Transmitter (Foxboro 13A)
  • Smart Integrated Transmitters
  • Target Meters
  • Variable Area Flowmeters (Rotameters)
• Mass Flowmeters
  • The Coriolis Meter
• 

  A Nutating Disc PD Flowmeter.

  Positive Displacement Flowmeters

  • Oscillating Piston Flowmeter
  • Rotating Vane Flowmeter
  • Nutating Disc Flowmeter

 

What time is it, Fred?

 

Time to start learning about the PV FLOWRATE, Fred!

 

 

TAKE HOME MESSAGES: The Instructional Plan for the PTOA PV Flowrate Focus Study Area is revealed.  

PTOA Readers and Students reviewed that the PV Flowrate is increased and decreased by a Pressure Differential, the higher the Pressure Differential, the greater the Flowrate ... and vice versa.

PTOA Readers and Students also reviewed the PV Pressure ↔ Fluid Velocity Swap which is also called "The Venturi Effect."

PTOA Readers and Students learned that the PV Flowrate is associated with low tech hardware that form Piping Networks and include:

• Joined Pipes or Tubes
• Pipe Fittings
• Common and Special Valves
• Piping Auxiliaries.

 

©2022 PTOA Segment 0233

PTOA PV FLOWRATE FOCUS STUDY AREA
INTRODUCTION TO THE PV FLOWRATE

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