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DAYALBAGH EDUCATIONAL INSTITUTE

TECHNICAL COLLEGE

A STUDY RELATED TO MEASURING, INDICATING AND CONTROLLING INSTRUMENTS

IN INDUSTRIAL PROCESSES: A PROJECT REPORT

DURING SUMMER TRAINING WITH SRF MALANPUR

Anhad KashyapAnhad KashyapAnhad KashyapAnhad Kashyap Sumit SaraswatSumit SaraswatSumit SaraswatSumit Saraswat 2nd Year, Roll no: 066153 2nd Year, Roll no: 066109 Diploma in Electronics Engineering Diploma in Electronics Engineering DEI Technical College DEI Technical College

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PREFACE

We are extremely thankful to SRF Malanpur for having consented to give us Summer Training as part of the Course Curriculum of the DEI Technical College, 3 Year Diploma Course.

As students accustomed to an academic environment in classrooms, it was a very different experience visiting a live working Production Plant. The learning was enormous and the experience was very special. We could understand how the theory of classrooms gets converted into actual production practice – creating things of social value. We even realized that certain subjects which are not much interesting such as Control Systems have great importance in automation world. They have great importance in the practical and industrial world.

We are very thankful to Mr. Mohd Aqib of SRF who arranged and over saw our training in SRF. Our special thanks are also due to Mr. Sarvendra Singh Bhadoria, Mr. Vivek Senger, Mr. A.K. Dwivedi, Mr. Abhishek Vyas & Mr. Manoj Matthew who took keen interest and took time out of their busy schedule to explain to us the details of the Technical Textile Production processes.

Our special thanks are due to Mr. Sandeep Paul, DEI Technical College, for his constant guidance and encouragement.

Last but not the least we would like to record our grateful thanks to Dr. B.B. Rao, Head of Electrical Department for his inspiration and guidance to us which he gave to us liberally from time to time.

We dedicate this humble effort in the Feet of the Lord Almighty Who has constantly Showered us with His Grace, Blessings and Protection.

(Anhad Kashyap) (Sumit Saraswat) 2nd Year, Roll no: 066153 2nd Year, Roll no: 066109 Diploma in Electronics Engineering Diploma in Electronics Engineering DEI Technical College DEI Technical College

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CONTENTS

I KNOWING SRF: Page No. 1. 1.1 Principles that govern SRF 5 1.2 SRF Purpose 6 1.3 SRF Aspiration 2020 7

2. SRF : Profile 8 3. The Mantra of Total Quality Management 11

4. SRF : Market Share 12

5. SRF : Tyre Cord Fabrics 13

6. SRF : Environmental Performance 14

7. SRF : Some General Facts 15

II TECHNICAL TEXTILE BUSINESS (TTB): SRF MALANPUR PLANT

8. About SRF Malanpur TTB Plant 16 9. Technical Textile Business Illustration 17 10. TTB - Volume Chain & Typical Application 18

11. Manufacturing Of Nylon Tyre Cord Fabric 19

12. Polymerisation 20

12.1 Polymerisation Process: Description 21

13. Spinning 22

13.1 Spinning Process 23 13.2 Spinning Process: Description 24

14. Twisting & Weaving 25

14.1 Twisting & Weaving Process 29

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III INSTRUMENTATION IN INDUSTRIAL PROCESSES OF SRF MALANPUR: NYLON TYRE CORD FABRIC PLANT

15. Instrumentation Engineering 30 16. Pressure Measuring, Indicating and 31

Controlling Instruments

17. Temperature Measuring, Indicating and 38 Controlling Instruments

18. Flow Measuring, Indicating and 43 Controlling Instruments

19. Level Measuring, Indicating and 51 Controlling Instruments

20. Controlling Pressure through Automation 57 21. Controlling Temperature through Automation 57 22. Controlling Level through Automation 58 23. Controlling Flow through Automation 58

IV CONCLUDING REMARKS 59

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I. KNOWING SRF

1.1 PRINCIPLES THAT GOVERN SRF

People-related Principles

• Create a win/win situation for all stakeholders.

• Leadership by example.

• Self discipline.

• Participation by all.

• Continuing education for all.

Work-related Principles

• Focus on Quality, not short-term profits.

• Market in, not product out.

• Be customer oriented.

• Work with facts and data.

• Act on causes, not just phenomena.

• Be process oriented.

• Prioritize

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1.2 SRF PURPOSE

““““We will make our nation proud We will make our nation proud We will make our nation proud We will make our nation proud by being the best at what we do.by being the best at what we do.by being the best at what we do.by being the best at what we do.””””

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1.3 SRF's ASPIRATION 2020

““““We Aspire to Achieve GlobaWe Aspire to Achieve GlobaWe Aspire to Achieve GlobaWe Aspire to Achieve Global l l l Leadership by continuously Leadership by continuously Leadership by continuously Leadership by continuously enhancing Organizational and enhancing Organizational and enhancing Organizational and enhancing Organizational and People Capability, Developing People Capability, Developing People Capability, Developing People Capability, Developing Innovative Products and Innovative Products and Innovative Products and Innovative Products and

Processes that satisfy Customers Processes that satisfy Customers Processes that satisfy Customers Processes that satisfy Customers and attaining challenging and attaining challenging and attaining challenging and attaining challenging

Benchmarks in ProductivityBenchmarks in ProductivityBenchmarks in ProductivityBenchmarks in Productivity....””””

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2. SRF: PROFILE

Established in 1973, SRF Ltd. is a leading Indian player in Technical Textiles, Refrigerant Gases and having operating interests in Packaging Films and Pharma Intermediates sectors. With seven production units in India and one overseas in Dubai under its fold, the company exports its products to over 60 countries.

Building on the strength of its TQM philosophy as a part of its daily life, the company added a new feather in its cap in the year 2004 when it became the first tyre cord company in the world to win the prestigious Deming Application Prize for Total Quality Management.

SRF

Technical Packaging Textile Business Films

Chemical Business

2.1 Technical Textile Business

Building on its dominant position in the domestic market, SRF enjoys a significant presence in the global market as well for all the three products under its Technical Textile Business - tyre reinforcements, belting fabrics and coated fabrics. Its tyre cord fabrics are used as reinforcement material for all categories of tyres – from bicycles to heavy commercial vehicles. The company’s Belting Fabrics are used as reinforcement material for manufacturing conveyour belts and its coated fabrics find applications as static and dynamic covers in various areas ranging from Agriculture to Defence applications.

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2.2 Chemical Business

SRF's Chemicals Business includes the Fluorochemicals and Fluorospecialities business lines. In the Fluorocarbon business space, SRF has grown to become the undisputed domestic market leader in its core product line of Refrigerant gases, while exporting two-thirds of its production to world-class international buyers spread across 60 countries. Refrigerant gases are used for a variety of industrial, commercial and household applications such as refrigeration and air-conditioning, as a blowing agent for insulating foam, as a propellant for aerosols, in mobile air conditioning, and as a propellant in metered dose inhalers for pharmaceutical companies.

SRF has also been taken initiatives under the guidelines of UNFCCC (United Nations Framework Convention on Climate Change) as a part of its Clean Development Mechanism (CDM). SRF entered into the Fluorospecialities business in 2003-04 as a natural progression of its expertise in Fluorochemicals and its strong knowledge of halogen chemistry. This business is focused on addressing the need for complex organo-fluorine compounds.

2.3 Packaging Films

The company’s Packaging Film Business produces PET films, which are used in packaging of food, cosmetics, personal and health care products. The focus of the business is to move up the value chain of packaging films and towards this end, it is a supplier of metallised films and holographic films apart from plain and chemically treated polyester films.

2.4 Growth Plans

SRF is growing very fast in tune with its aspiration to achieve global leadership by 2020. It has recently announced its investment plan to install a polyester industrial yarn plant at its existing Gummidipoondi plant near Chennai. With its maiden entry into the polyester yarn SRF will thus become a one-stop shop for reinforcement fabric to the tyre companies in India.

Furthermore, among other projects the company is also planning to set up a new Chemical Complex at Dahej in Gujarat, which is fast developing as a premiere choice for such projects. In view of its healthy financial situation, the company is actively considering to expand its business through the inorganic route in its core area of business.

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2.5 Key Milestones

• In 2004, SRF became the first tyre cord company in the world to win the prestigious Deming Application Prize for Total Quality Management

• Mr. Arun Bharat Ram, chairman SRF, conferred with the prestigious Jamshetji Tata Award from the Indian Society for Quality (ISQ) for the year 2006.

• SRF’s Chemical Business awarded with Responsible Care Logo by Indian Chemical Council (ICC), Mumbai

• SRF conferred with the prestigious Greentech Safety Platinum Award 2006-07

• SRF conferred with the prestigious Greentech Environment Excellence Platinum Award 2007

• SRF developed processes to manufacture HFC 134a, HFC 32 (different varieties of new generation refrigerant gases) through in-house R&D efforts.

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3. THE MANTRA OF TOTAL QUALITY MANAGEMENT

At SRF, Total Quality Management is a management approach that profoundly integrates principles, methods, systems and tools, and transforms the way people in the organization think and do things, as well as the way in which they manage it. Thanks to TQM, SRF has made fundamental improvements in all areas resulting in satisfied stakeholders.

The TQM journey at SRF is characterized by three key methods of management.

• Daily Management – which is a means to preserve status quo and make continuous improvements.

• Breakthrough Management – Which provides a method for making quantum improvements or breakthroughs.

• Upstream Management - which prevents potential problems from arising at the production stage and creates products which satisfy customers.

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4. SRF: MARKET SHARE

• Domestic market share

• Tyre Cord Fabric - Approx 35% market share, No 1 in India.

• Chloromethane and Refrigerant Gases - Approx 39% market share, No 1 in India.

• Belting Fabrics - Approx 70% market share, No 1 in India

• Packaging Films - Approx 25,700 TPA consolidated capacity

• Global Market Leadership

• Eighth largest player in Tyre Cord Fabric

• Second largest player in Belting Fabrics

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5. SRF: TYRE CORD FABRICS

“Whether you ride a bicycle, a motorbike, a car, a truck or even a plane, SRF is the company that provides the tyre cord, which assures you a smooth safe ride!”

The Technical Textiles Business manufactures Tyre Cord Fabric which is used as reinforcement for all kinds of tyres – be it bicycles or heavy commercial vehicles.

SRF is the domestic market leader and the third largest Nylon 6 tyre cord producer in the world.

SRF has over 30 years of expertise in making tyre cord fabric. With significant business in Europe, Middle East and Africa, its customer portfolio includes all Indian tyre companies and Global tyre majors.

SRF has four plants in India located at Manali (Tamil Nadu), Malanpur (Madhya Pradesh), Gummidipoondi (Tamil Nadu), Viralimali (Tamil Nadu) and one in Jebel Ali (Dubai). Two plants have fully integrated facility from Polymerization to Fabric. SRF is the only Indian tyre cord company having dipping facility. All plants are ISO certified and most with ISO 14000 and one with ISO 18000.

The Technical Textiles Business has a Research & Development Center located in Manali (Tamil Nadu) with a pilot facility for new product and process development. R&D Center has the capability to take up joint development projects with customers.

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6. SRF: ENVIRONMENTAL MANAGEMENT

• Management Approach • Energy and Fuel Conservation

• Water Management

• Controlling Air Pollution

• Land and Biodiversity

• Waste Management

• Green House Gases: Emission and Control

• Chemical Spills

• Transportation of Hazardous Chemicals

• Compliance and Statuary Requirements

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7. SRF: SOME GENERAL FACTS

BACKGROUND OF SRF

• Business group established in 1889. • Started as Shriram Fibres in 1978.

CERTIFICATE OF REGISTRATION

• ISO 14001:2004 – Environmental Management. • ISO 9001:2000 – Quality Management.

LOCATIONS IN INDIA

• Corporate Office - (Gurgaon) • Fluoro Chemical Business – (Bhiwadi) • Polyester Film – (Indore) • Polyester Film – (Kashipur) • Technical Textile Business – (Goomidipondi) • Technical Textile Business – (Trichi) • Technical Textile Business – (Gwalior) • Technical Textile Business – (Manali)

GLOBAL PRESENCE

• SRF Overseas (Dubai) • SRF Americas (US)

GLOBAL ALLIANCES/COLLABORATIONS

• DuPoint, Honeywell, Toray, Atochem etc. • Export to more than 60 countries.

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II. TECHNICAL TEXTILE BUSINESS (TTB)

8. ABOUT SRF TTB MALANPUR PLANT

• Location – Malanpur Industrial Area, Malanpur, District Bhind, Madhya Pradesh.

• Collaborator – M/S TORAY Industries Inc. Japan

• Total Land – 73 Acres (Including Green Land of 30 Acres)

• Total Investment – 350 Crores

• Manpower – 539 (Officers, Staff & Workmen)

• Product Manufactured – Nylon Tyre Cord Fabric (NTCF)

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9. TECHNICAL TEXTILE BUSINESS (TTB) ILLUSTRATION SRF Malanpur plant is manufacturing Nylon Tyre Cord Fabric (NTCF). The flow cycle of suppliers, competitors, customers and product application is shown below diagrammatically.

SUPPLIERS

Lactum – FACT, GSFC, DSM (Imports)

Yarn – PT Filamendo, Asahi, Chemlon

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PRODUCT COMPETITORS

APPLICATION NYLON TYRE CORD FABRIC India: Cenkas, NRC,

Tyre Reinforcement (NTCF) Nirlon

Inter.: Thailand,

Taiwan, South Korea, Indonesia & China

CUSTOMERS

India: Appolo, MRF, JK TYRES Vikrant, Goodyear

Inter: Iran, Europe, Srilanka, Indonesia, Thailand

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10. TTB – VOLUME CHAIN & TYPICAL APPLICATION The process of manufacture of Nylon Tyre Cord Fabric (NTCF) is shown below in diagrammatic form.

YARN SPINNERS

CONVERTERS

Caprolactum

Polymer Chip

Tyre Yarn

Greige Tyre Cord Fabric

Dipped Tyre Cord Fabric

Polymerisation

Spinning

Twisting & Weaving

Dipping

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DIAGRAM OF A TYRE

11. MANUFACTURING OF NYLON TYRE CORD FABRIC

• Raw Material :-

• Caprolactum is an organic compound which is a Lactum of 6- aminohexanoic acid (ε-aminohexanoic acid, aminocaproic acid). It can alternatively be considered cyclic amide of caproic acid.

• The primary industrial use of Caprolactum is as a monomer in the production of nylon-6. Most of the Caprolactum is synthesised from cyclohexanone via an oximation process using hydroxyl

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ammonium sulfate followed by catalytic rearrangement using the Beckmann rearrangement process step.

• Major worldwide producers include BASF, Honeywell, DSM (Dutch State Mines), Bayer, Toray and Sumitomo/Enichem.

Properties

Molecular formula C6H

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Molar mass 113,16 g/mol

Density 1,01 g/cm3

Melting point 68 °C

Boiling point 136-138 °C / 10 mm Hg

Solubility in water 4560 g/l

• Caprolactum is an irritant and is toxic by ingestion, inhalation, or absorption through the skin.

• Processes Involved :-

• Polymerisation

• Spinning

• Twisting & Weaving

• Use of Product – Used for the Manufacturing of tyres

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POLYMERISATION

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12. POLYMERISATION

In polymer chemistry, polymerization is a process of reacting monomer molecules together in a chemical reaction to form three-dimensional networks or polymer chains. There are many forms of polymerization and different systems exist to categorize them.

• The main categories are :-

• Addition polymerization

• Condensation polymerization

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The Polymerisation section comprises of the following sub sections:-

• LACTAM Preparation

• Deoxygen

• Polymerisation

• Extraction

• Solid State Polymerisation

• Chip Transportation

• Chip Silo

• Concentration

• Distillation

Diagrammatic representation of the Polymerisation process is given below.

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POLYMERISATION PROCESS

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12.1 POLYMERISATION PROCESS – DESCRIPTION • Caprolactum is melted in the Lactum Preparation Plant and then sent for

Polymerisation where it is stored in the Lactum Storage tank. • 3 % DM Water is added to it. The DM Water acts as a catalyst. • It is heated and then filtered through a micron filter from where it is sent

for deoxygenating. • Then in the Deoxygen process oxygen is sucked from the Lactum so as to

prevent oxidation of the Lactum as oxidation can lead to change in colour. • In the Polymerisation process, the Lactum is heated in the first reactor at

about 2700 c. Then it is sent for 2nd Polymerisation process where the temperature is reduced 35–40 0 c. Here it is converted to ribbon and sent to the chip cutter for cutting it into fine sugar size cubical chips.

• Parallel to this all the monomer collected is sent to the Lactum preparation

section for recycling. Similarly the recovered Lactum from the extracted water is sent to the Lactum storage tank.

• In the Extraction process which is next to 2nd Polymerisation, the monomer

is extracted from the chips of polymer. Then in the second phase of extraction 8 to 10 hours chips are held in the container. Maximum of 9 tons of chips are held.

• All the monomer is recovered and recycled for use. DM Water is added

continuously. Still 0.5 to 1 % of monomer is left in the chips. • Now the water is separated from the chips by centrifuging. Now the chips

after extraction are taken from solid state Polymerisation where they are heated with nitrogen. Nitrogen provides resistance from oxidation.

• Then the chips are transported to the spinning section through pipes

which has nitrogen blowing at high pressure. • We can see Diagram 1.0 to get a clear idea about the processes involved in

making of nylon 6 chips.

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SPINNING

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13. SPINNING

Spinning is an ancient textile art in which plant, animal or synthetic fibers are twisted together to form yarn (or thread, rope, or cable). The direction in which the yarn is spun is called twist. Yarns are characterized as Z-twist or S-twist according to the direction of spinning (see diagram). Tightness of twist is measured in TPI (twists per inch or turns per inch).

Two or more spun yarns may be twisted together or plied to form a thicker yarn. Generally, handspun single plies are spun with a Z-twist, and plying is done with an S-twist.

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13.1 SPINNING PROCESS

Diagrammatic representation of the Spinning process is given below.

Chips from PolymerisationChips from PolymerisationChips from PolymerisationChips from Polymerisation

Dry ChipsDry ChipsDry ChipsDry Chips

Additive MixingAdditive MixingAdditive MixingAdditive Mixing

ExtrusionExtrusionExtrusionExtrusion

QuenchingQuenchingQuenchingQuenching

Finish Oil AppliFinish Oil AppliFinish Oil AppliFinish Oil Applicationcationcationcation

DrawingDrawingDrawingDrawing

WindingWindingWindingWinding

Yarn CheeseYarn CheeseYarn CheeseYarn Cheese

To Packing

To Textile

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13.2 SPINNING PROCESS – DESCRIPTION • The chips stored in the chip silos are transported to the chip receiver. • Now an additive special mixture is prepared by mixing CuI + 20 Kg of

chips. • All the process is in presence of Nitrogen. • Now the nitrogen is extracted under pressure. • The yarn cheese produced is then sent to the Textile Section.

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TWISTING & WEAVING

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14. TWISTING & WEAVING Twisting in yarn and rope production, process that binds fibres or

yarns together in a continuous strand, accomplished in spinning or playing operations. The direction of the twist may be to the right, described as Z twist, or to the left, described as S twist. Single yarn is formed by twisting fibres or filaments in one direction. Ply yarn is made by twisting two or more single yarns.

Weaving is an ancient textile art and craft that involves placing two sets of threads or yarn called the warp and weft of the loom and turning them into cloth. This cloth can be plain (in one color or a simple pattern), or it can be woven in decorative or artistic designs, including tapestries.

In general, weaving involves the interlacing of two sets of threads at right angles to each other: the warp and the weft. The warps are held taut and in parallel order, typically by means of a loom, though some forms of weaving may use other methods. The loom is warped (or dressed) with the warp threads passing through heddles on two or more harnesses. The warp threads are moved up or down by the harnesses creating a space called the shed. The weft thread is wound onto spools called bobbins. The bobbins are placed in a shuttle which carries the weft thread through the shed. The raising/lowering sequence of warp threads gives rise to many possible weave structures from the simplest plain weave (also called tabby), through twills and satins to complex computer-generated interlacings.

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Both warp and weft can be visible in the final product. By spacing the warp more closely, it can completely cover the weft that binds it, giving a warpfaced textile such as rep weave. Conversely, if the warp is spread out, the weft can slide down and completely cover the warp, giving a weftfaced textile, such as a tapestry or a Kilim rug. There are a variety of loom styles for hand weaving and tapestry. In tapestry, the image is created by placing weft only in certain warp areas, rather than across the entire warp width.

14.1 TWISTING & WEAVING PROCESS Diagrammatic representation of the Twisting & Weaving process is given below.

Yarn CheeseYarn CheeseYarn CheeseYarn Cheese

TwistingTwistingTwistingTwisting

Loom Loom Loom Loom

WeavingWeavingWeavingWeaving

PackingPackingPackingPacking

DispatchDispatchDispatchDispatch

To Customers

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INSTRUMENTATION

IN

INDUSTRIAL PROCESSES

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III INSTRUMENTATION IN INDUSTRIAL PROCESSES OF SRF MALANPUR, NYLON TYRE CORD FABRIC PLANT

15. INSTRUMENTATION ENGINEERING is the engineering

specialization focused on the principle and operation of measuring instruments which are used in design and configuration of automated systems. They typically work for industries with automated processes, such as chemical or manufacturing plants, with the goal of improving system productivity, reliability, safety, optimization and stability.

Instrumentation can be used to measure certain field parameters (physical values):

• pressure, either differential or static • flow • temperature • level • density • viscosity • radiation • current • voltage • inductance • capacitance • frequency • resistivity • conductivity • chemical composition • chemical properties • various physical properties • force applied by a liquid

We are going to take the following into consideration:

• Pressure • Temperature • Flow • Level

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PRESSURE INSTRUMENTS

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16.1 PRESSURE MEASURING, INDICATING AND CONTROLLING INSTRUMENTS

Pressure is defined as the normal force per unit area exerted by a fluid (liquid or gas) on any surface. The surface can be either a solid boundary in contact with the fluid or, for purposes of analysis, an imaginary plane drawn through the fluid. Only the component of the force normal to the surface needs to be considered for the determination of pressure. Tangential forces that give rise to shear and fluid motion will not be a relevant subject of discussion here. In the limit that the surface area approaches zero, the ratio of the differential normal force to the differential area represents the pressure at a point on the surface. Furthermore, if there is no shear in the fluid, the pressure at any point can be shown to be independent of the orientation of the imaginary surface under consideration. Finally, it should be noted that pressure is not defined as a vector quantity and is therefore nondirectional. Three types of pressure measurements are commonly performed:

• Absolute pressure is the same as the pressure defined above. It represents the pressure difference between the point of measurement and a perfect vacuum where pressure is zero.

• Gage pressure is the pressure difference between the point of

measurement and the ambient. In reality, the ambient (atmospheric) pressure can vary, but only the pressure difference is of interest in gage pressure measurements.

A rugged capacitive pressure sensor product for industrial applications. It incorporates the sensing cell shown in Figure 26.3. Readout electronics are contained in the housing at the

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top. (Courtesy of Rosemount, Inc) Pressure is a very important factor involved in industrial processes. Pressure can be of two types:

• Differential Pressure

Apart from the differential producer, the other main element of a differential pressure flow meter is the transducer needed to measure the pressure drop across the producer. The correct selection and installation of the differential pressure transducer plays an important part in determining the accuracy of the flow rate measurement.

• Static Pressure

The main factors that should be considered when choosing a differential pressure transducer for a flow measurement application are the differential pressure range to be covered, the accuracy required, the maximum pipeline pressure, and the type and temperature range of the fluid being metered. DEFINING TERMS

• Differential Pressure Flow Meter A flow meter in which the pressure drop across an annular restriction placed in the pipeline is used to measure fluid flow rate. The most common types use an orifice plate, Venturi tube, or nozzle as the primary device.

• Orifice plate: Primary device consisting of a thin plate in which a circular aperture has been cut.

• Venturi tube: Primary device consisting of a converging inlet, cylindrical

mid-section, and diverging outlet.

• Nozzle: Primary device consisting of a convergent inlet connected to a cylindrical section.

The instruments used for measuring differential pressure are different from that of measuring static pressure. The instruments used for measuring, indicating and controlling pressure in various processes in SRF are:-

• Pressure Gauge – For measuring pressure in a system. • Pressure Transmitter – For measuring pressure in a system and

transmitting a digital signal which ranges from 4mA – 20mA. • Pressure Indicator Controller – For indicating and controlling pressure

in s system.

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16.2 PRESSURE GAUGE / PRESSURE TRANSMITTER

(Gauge only measures, it does not communicate or transmit electrical signal)

Manufacturer: Rosemount, Honeywell

Models Used: Rosemount 1151, 1144, 1135, 444, 2051

Introduction: To measure differential pressure of flow, liquid level, and other applications requiring measurement. It is installed in harsh environments.

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Principle: Pressure transmitters translate low-level electrical outputs from pressure sensing devices to higher-level signals that are suitable for transmission and processing. They use many different sensing technologies and can measure the pressure of liquids and/or gases. Mechanical deflection devices such as diaphragms, Bourdon tubes or bellows consist of an elastic or flexible element that is deflected mechanically by a change in pressure. Devices that use sealed pistons or cylinders are also available. Strain gauges are often bonded to a larger structure that deforms as pressure changes. Resistive devices sense shifts of electrical charges within a resistor. Piezoelectric pressure transmitters measure dynamic and quasi-static pressures. Their common modes of operation are charge mode, which generates a high-impedance charge output; and voltage mode, which uses an amplifier to convert the high-impedance charge into a low-impedance output voltage. Thin film devices consist of an extremely thin layer of material, usually titanium nitride or poly silicon, deposited on a substrate. Pressure transmitters that use micro electromechanical systems (MEMS), variable capacitance, and vibrating elements are also available.

Working: Pressure transmitters are capable of performing various pressure measurements and displaying amounts in different units. Absolute pressure is a pressure measurement that is relative to a perfect vacuum. Typically, vacuum pressures are lower than the atmospheric pressure. Gage pressure, the most common type of pressure measurement, is relative to the local atmospheric pressure. By contrast, sealed gauge pressure is relative to one atmosphere of pressure (oz) at sea level. Differential pressure reflects the difference between two input pressures. Compound pressure instruments can display both positive and negative pressures. Some pressure transmitters display values in pounds per square inch, kilo Pascal’s, bars or millibars, inches or centimeters of mercury, or inches or feet of water. Other devices display measurements in ounces per square inch or kilograms per square centimeter.

Output Signal: 4 – 20 mA

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16.3 PRESSURE INDICATOR CONTROLLER SLCD Indicating Controller (Style E)

Manufacturer: Yokogawa Models: SLCD – 151, 181, 251, 281 Introduction: The SLCD Indicator Controller can not only be used to

control pressure, it can be used for any controlling any process whether temperature or flow. The Model SLCD Indicating Controller is a microprocessor-based controller, suitable for process control. Control functions include non-linear control and feed forward control. The tracking input is equipped for cascade control and selector control performed by multiple controllers.

Features:

• Intelligent self-tuning model automatically optimizes PID parameters.

• Using side-panel keypad, you can select PID or PD control algorithms, functions such as remote setting, feed forward control and output tracking. Adjustable set-point filtering allows response to set point changes to be optimized. Signal-processing functions include square-root, linearization and cascade set point scaling computation.

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• Communication functions allow the SLCD controller to be used with a central CRT-display operator station. DDC or SPC operation is also possible.

• Incorporates I/O signal level checks and self diagnostics.

(a) ROSEMOUNT 1151 PRESSURE TRANSMITTER

The Rosemount 1151 has provided the process control industry with unsurpassed service since 1969. Today, the Rosemount 1151 remains one of the world's most popular transmitters with an installed base of over 4 million.

• Measure differential, gage, absolute, and draft pressure as well as models for use in battery or solar power applications.

• Ranges from 0.5 in H2O to 6,000 psig (0–0.12 KPa to 0–41 MPa) • Accurate measurement using the capacitance principle, virtually

unaffected by changes in temperature, static pressure, vibration, and power supply voltage.

• The Smart Retrofit Kit makes it possible to convert the Rosemount 1151 Pressure Transmitter into a microprocessor-based (smart) operation.

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16.4 PRESSURE SENSOR

Pressure sensors can be classified in term of pressure ranges they measure, temperature ranges of operation, and most importantly the type of pressure they measure. In terms of pressure type, pressure sensors can be divided into five categories:

• Absolute pressure sensor

This sensor measures the pressure relative to perfect vacuum pressure (0 PSI or no pressure). Atmospheric pressure is about 100 kPa (14.7 PSI) at sea level. Atmospheric pressure is an absolute pressure.

• Gauge pressure sensor

This sensor is used in different applications because it can be calibrated to measure the pressure relative to a given atmospheric pressure at a given location. An example of gauge pressure would be a tire pressure gauge. When the tire pressure gauge reads 0 PSI, there is really 14.7 PSI (atmospheric pressure) in the tire.

• Vacuum pressure sensor

This sensor is used to measure pressure less than the atmospheric pressure at a given location.

• Differential pressure sensor

This sensor measures the difference between two or more pressures introduced as inputs to the sensing unit, for example, measuring the pressure drop across an oil filter. Differential pressure is also used to measure flow or level in pressurized vessels.

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TEMPERATURE INSTRUMENTS

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17. TEMPERATURE MEASURING, INDICATING & CONTROLLING INSTRUMENTS

Temperature is a physical property of a system that underlies the common notions of hot and cold; something that is hotter generally has the greater temperature. Specifically, temperature is a property of matter. Temperature is one of the principal parameters of thermodynamics. On the microscopic scale, temperature is defined as the average energy of microscopic motions of a single particle in the system per degree of freedom. On the macroscopic scale, temperature is the unique physical property that determines the direction of heat flow between two objects placed in thermal contact. If no heat flow occurs, the two objects have the same temperature; otherwise heat flows from the hotter object to the colder object. These two basic principles are stated in the zeroth law and second law of thermodynamics, respectively. For a solid, these microscopic motions are principally the vibrations of its atoms about their sites in the solid. For an ideal monatomic gas, the microscopic motions are the translational motions of the constituent gas particles. For a multiatomic gas, vibrational and rotational motion should be included too.

INTRODUCTION TO RESISTANCE TEMPERATURE DETECTORS

One common way to measure temperature is by using Resistive Temperature Detectors (RTDs). These electrical temperature instruments provide highly accurate temperature readings: simple industrial RTDs used within a manufacturing process are accurate to ±0.1°C, while standard Platinum Resistance Thermometers (SPRTs) are accurate to ±0.0001°C. The electric resistance of certain metals changes in a known and predictable manner, depending on the rise or fall in temperature. As temperatures rise, the electric resistance of the metal increases. As temperatures drop, electric resistance decreases. RTDs use this characteristic as a basis for measuring temperature. The sensitive portion of an RTD, called an element, is a coil of small-diameter, high-purity wire, usually constructed of platinum, copper, or nickel. This type of configuration is called a wire-wound element. With thin-film elements, a thin film of platinum is deposited onto a ceramic substrate. Platinum is a common choice for RTD sensors because it is known for its long-term stability over time at high temperatures. Platinum is a better choice than copper or nickel because it is chemically inert, it withstands oxidation well, and works in a higher temperature range as well. In operation, the measuring instrument applies a constant current through the RTD. As the temperature changes, the resistance changes and the corresponding change in voltage is measured. This measurement is then converted to thermal values by a computer. Curve-fitting equations are used to define

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this resistance vs. temperature relationship. The RTD can then be used to determine any temperature from its measured resistance. A typical measurement technique for industrial thermometers involves sending a constant current through the sensor (0.8 mA to 1.0 mA), and then measuring the voltage generated across the sensor using digital voltmeter techniques. The technique is simple and few error-correcting techniques are applied. In a laboratory where measurement accuracies of 10 ppm or better are required, specialized measurement equipment is used. High-accuracy bridges and digital voltmeters with special error-correcting functions are used. Accuracies of high-end measurement equipment can reach 0.1 ppm (parts per million). These instruments have functions to compensate for errors such as thermoelectric voltages and element self-heating. In addition to temperature, strain on and impurities in the wire also affect the sensor’s resistance vs. temperature characteristics. The Matthiessen rule states that the resistivity (r) of a metal conductor depends on temperature, impurities, and deformation. r is measured in (W cm)

p (Total) = p (temperature) + p (impurities) + p (deformation)

RTD CONSTRUCTION Standard Platinum Resistance Thermometers (SPRTs), the highest-accuracy platinum thermometers, are fragile and used in laboratory environments only Figure. Fragile materials do not provide enough strength and vibration resistance for industrial environments. SPRTs feature high repeatability and low drift, but they cost more because of their materials and expensive production techniques. SPRT elements are wound from large-diameter, high-purity platinum wire. Internal lead wires are usually made from platinum and internal supports from quartz or fused silica. SPRTs are used over a very wide range, from –200°C (–328°F) to above 1000°C (1832°F). For SPRTs used to measure temperatures up to 660°C (1220°F), the ice point resistance is typically 25.5 W. For high-temperature thermometers, the ice point resistance is 2.5 W or 0.25 W. SPRT probes can be accurate to ±0.001°C (0.0018°F) if properly used. Secondary Standard Platinum Resistance Thermometers (Secondary SPRTs) are also intended for laboratory environments. They are constructed like the SPRT, but the materials are less expensive, typically reference-grade, high-purity platinum wire, metal sheaths, and ceramic insulators. Internal lead wires are usually a nickel-based alloy. The secondary grade sensors are limited in temperature range — –200°C (–328°F) to 500°C (932°F) — and are accurate to ±0.03°C (±0.054°F) over their temperature range. Secondary standard thermometers can withstand some handling, although they are still quite strain free. Rough handling, vibration, and shock will cause a shift in calibration. The nominal resistance of the ice point is most often 100 W. This simplifies calibration procedures when calibrating other 100-W RTDs. The temperature coefficient for secondary standards using

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reference-grade platinum wire is usually 0.00392 W W–1 °C–1 or higher. Industrial Platinum Resistance Thermometers (IPRTs) are designed to withstand industrial environments and are almost as durable as thermocouples. IEC 751 [1] and ASTM 1137 [2] standards cover the requirements for industrial platinum resistance thermometers. The most common temperature range is –200°C (–328°F) to 500°C (932°F). Standard models are interchangeable to an accuracy of ±0.25°C (±0.45°F) to ±2.5°C (±4.5°F) over their temperature range.

The instruments used for measuring, indicating and controlling temperature in various processes in SRF are:-

• Thermistors – For measuring temperature in a system. • Resistance Temperature Detector (RTD) – For measuring temperature. • Temperature Transmitter– For measuring temperature in a system and

transmitting a digital signal which ranges from 4mA – 20mA. • Temperature Indicator Controller – For indicating and controlling

temperature in s system.

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RESISTANCE TEMPERATURE DETECTOR (RTD) – 2 WIRE TRANSMITTERS

Manufacturer: Switzer, Rosemount, Honeywell, & Yokogawa

Models Used: K-5602

Introduction: It employs the latest 2 wire precision integrated chip with optional linearity. It is used to measure temperature of flow, and other applications require temperature measurement. Resistance thermometers, respond to temperature by changing their electrical resistance. Two common types of resistance thermometers are resistance temperature detectors (RTDs), which have metallic sensing elements and Thermistors which have semiconductor elements.

Principle: An RTD consists of a sensing element fabricated of metal wire or metal fiber which responds to temperature change by changing its resistance. The sensor is connected to a readout instrumentation that monitors the resistance, typically through the use of a bridge circuit, and then converts resistance to a temperature value.

Working: An RTD is a passive measurement device; therefore, you must supply it with an excitation current and then read the voltage across its terminals. You can then easily transform this reading to temperature with a simple algorithm. To avoid self-heating, which is caused by current flowing through the RTD, minimize this excitation current as much

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as possible. The easiest way to take a temperature reading with an RTD is using the 2-wire method.

Figure 2. Making a 2-Wire RTD Measurement

Using the 2-wire method, the two wires that provide the RTD with its excitation current and the two wires across which the RTD voltage is measured are the same. The inaccuracy using this method is that if the lead resistance in the wires is high, the voltage measured V

O, is significantly

higher than the voltage that is present across the RTD itself. To get a more accurate measurement, use the 4-wire method.

Figure 3. Making a 4-Wire RTD Measurement

The 4-wire method has the advantage of not being affected by the lead resistances because they are on a high impedance path going through the device that is performing the voltage measurement; therefore, you get a much more accurate measurement of the voltage across the RTD.

Output Signal: 4 – 20 mA

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FLOW INSTRUMENTS

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18. FLOW MEASURING, INDICATING & CONTROLLING INSTRUMENTS

Units of measurement

Both gas and liquid flow can be measured in volumetric or mass flow rates (such as litres per second or kg/s). These measurements can be converted between one another if the materials density is known. The density for a liquid is almost independent of the liquids conditions, however this is not the case for a gas, whose density highly depends upon pressure and temperature.

In engineering contexts, the volumetric flow rate is usually given the symbol Q and the mass flow rate the symbol .

Gas

Due to the nature of an Ideal gas or a Real gas, the volumetric gas flow rate will differ for the same mass flow rate when at differing temperatures and pressures. As such gas volumetric flow rate is sometimes measured in "standard cubic centimeters per minute" (abbreviation sccm). This unit, although not an SI unit is sometimes used due to the additional information attached to the unit symbol, which indicates the temperature and pressure of the gas. Many other similar abbreviations are also in use, for two reasons, firstly mass flow and volumetric flow can be equated at known conditions, and secondly due to the imperial system older units such as standard cubic feet per minute or per second may still be used in some countries. It is often necessary to employ standard gas relationships (such as the ideal gas law) to convert between units of mass flow and volumetric flow.

Liquid

For liquids other units used depend on the application and industry but might include gallons (U.S. liquid or imperial) per minute, liters per second, bushels per minute and, when describing river flows, acre-feet per day.

Mechanical flow meters

There are several types of mechanical flow meter

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Piston Meter

Because they are used for domestic water measurement, piston meters, also known as rotary piston or semi-positive displacement meters, are the most common flow measurement devices in the UK and are used for almost all meter sizes up to and including 40 mm (1 1/2"). The piston meter operates on the principle of a piston rotating within a chamber of known volume. For each rotation, an amount of water passes through the piston chamber. Through a gear mechanism and, sometimes, a magnetic drive, a needle dial and odometer type display is advanced.

Woltmann Meter

Woltman meters, commonly referred to as Helix meters are popular at larger sizes. Jet meters (single or Multi-Jet) are increasing in popularity in the UK at larger sizes and are commonplace in the EU.

Multi-jet Meter

A multi-jet meter is a velocity type meter which has an impeller which rotates horizontally on a vertical shaft. The impeller element is in a housing in which multiple inlet ports direct the fluid flow at the impeller causing it to rotate in a specific direction in proportion to the flow velocity. This meter works mechanically much like a paddle wheel meter except that the ports direct the flow at the impeller equally from several points around the circumference of the element, where a paddle wheel normally only receives flow from one offset flow stream.

Venturi Meter

Another method of measurement, known as a venturi meter, is to constrict the flow in some fashion, and measure the differential pressure (using a pressure sensor) that results across the constriction. This method is widely used to measure flow rate in the transmission of gas through pipelines, and has been used since Roman Empire times.

Dall Tube

The Dall tube is a shortened version of a Venturi meter with a lower pressure drop than an orifice plate. Both flow meters the flow rate of Dall tube is determined by measuring the pressure drop caused by restriction in the conduit. The pressure differential is measured using diaphragm pressure transducers with digital read out. Since these meters have significantly lower permanent pressure losses than the orifice meters, the Dall tubes have widely been used for measuring the flow rate of large pipeworks.

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Orifice Plate

Another simple method of measurement uses an orifice plate, which is basically a plate with a hole through it. It is placed in the flow and constricts the flow. It uses the same principle as the venturi meter in that the differential pressure relates to the velocity of the fluid flow (Bernoulli's principle).

Pitot tube

A Pitot tube is a pressure measuring instrument used to measure fluid flow velocity by determining the stagnation pressure. Bernoulli's equation is used to calculate the dynamic pressure and thence fluid velocity.

Multi-hole Pressure Probe

Multi-hole pressure probes (also called impact probes) extend the theory of Pitot tube to more than one dimension. A typical impact probe consists of three or more holes (depending on the type of probe) on the measuring tip arranged in a specific pattern. More holes allow the instrument to measure the direction of the flow velocity in addition to its magnitude (after appropriate calibration). Three-holes arranged in a line allow the pressure probes to measure the velocity vector in two dimensions. Introduction of more holes e.g., five holes arranged in a 'plus' formation allow measurement of the three-dimensional velocity vector.

Paddle wheel

The paddle wheel translates the mechanical action of paddles rotating in the liquid flow around an axle into a user-readable rate of flow (gpm, lpm, etc.). The paddle tends to be inserted into the flow.

Pelton wheel

The Pelton wheel turbine (better described as a radial turbine) translates the mechanical action of the Pelton wheel rotating in the liquid flow around an axis into a user-readable rate of flow (gpm, lpm, etc.). The Pelton wheel tends to have all the flow traveling around it with the inlet flow focused on the blades by a jet. The original Pelton wheels were used for the generation of power and consisted of a radial flow turbine with "reaction cups" which not only move with the force of the water on the face but return the flow in opposite direction using this change of fluid direction to further increase the efficiency of the turbine.

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INDUSTRIAL FLOWMETER

An Industrial flowmeter used to measure flow rate of liquids & gases. It operates on the variable area principle, where the fluid flow raises a float in taper tube, increasing the area of passage of fluid. The greater the flow, the higher the float is raised. The height of float is directly proportional to the flow rate. With liquids, the float is raised by a combination of the buoyancy of the liquid and the velocity head of the fluid. With gases, the buoyancy is negligible, and float responds to the velocity head alone. The taper glass tube is formed of Borosilicate glass of extremely high accuracy of bore obtained by collapsing the taper tube while in hot and plastic state on a precision ground and polished mandril. The tubes are then annealed in furnace to relieve the stress formed during manufacturing. Floats of various configuration and material are used for a wide range of application depending upon flow rate, viscosity and turbidity of fluid. The float has a sharp metering edge where the reading is observed by means of scale mounted along side of the tube. The scale of rotameter is calibrated to directly read the fluid flow. The flow rate for any variable area flow rate can be expressed as

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PURGE ROTAMETER

Purge Rotameter Provides an economical means of flow rate indication of liquids and gases. A very wide variety version is offered to cover almost all requirements in Laboratories, Purging processes, analyzers, Semi conductors, Production Devices, Medical equipment and other Sampling lines.

- Flow Meter

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ORI - FLOW METER

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The Ori - flow meter measures flow by inserting an orifice at part of the

piping, generating differential pressure before and behind the orifice by

means of the flow, and extracting this differential pressure by a suitable

method. Differential pressure (P1-P2) of main orifice and the flow Q have

shown in equation given below. The flow is proportional to the square root

of the differential pressure.

Q: Volumetric flow C: Flow co-efficient F: Cross sectional area of orifice hole g: Acceleration of gravity P1-P2: Differential pressure Y: Specific weight of fluid

The generated differential pressure is sent to a manometer or other

differential pressure gauge and a differential flow meter can be formed by

attaching a flow scale to this gauge. However, since the flow indication is a

square root scale reading is difficult. Moreover, incase of remote

transmission it is inconvenient because the evolution operation is performed

to obtain linear relation.

Therefore if a by-pass pipe connecting the before and behind point of the

main orifice is installed and the flow is branched to that pipe to overcome

these disadvantage, that flow becomes proportional to the differential.

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LEVEL INSTRUMENTS

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19. LEVEL MEASURING, INDICATING & CONTROLLING INSTRUMENTS

Classification levels

According to the classification scheme, in statistics the kinds of descriptive statistics and significance tests that are appropriate depend on the level of measurement of the variables concerned

Stevens proposed four levels of measurement, described below:

• nominal (also categorical or discrete) • ordinal • interval • ratio

Interval and ratio variables are also grouped together as continuous variables.

The levels are in increasing order of mathematical structure—meaning that more operations and relations are defined—and the higher levels are required to define some statistics.

Level Can define… Relation or Operation Mathematical structure

nominal mode equality (=) set

ordinal median order (<) totally ordered set

interval mean, standard deviation

subtraction (-) and weighted average

affine line

ratio geometric mean, coefficient of variation

addition (+) and multiplication (×)

field

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Nominal measurement

In this type of measurement, names are assigned to objects as labels. This assignment is performed by evaluating, by some procedure, the similarity of the to-be-measured instance to each of a set of named exemplars or category definitions. The name of the most similar named exemplar or definition in the set is the "value" assigned by nominal measurement to the given instance. If two instances have the same name associated with them, they belong to the same category, and that is the only significance that nominal measurements have. Variables that are measured only nominally are also called categorical variables. etc.

Nominal numbers

For practical data processing the names may be numerals, but in that case the numerical value of these numerals is irrelevant, and the concept is now sometimes referred to as nominal number. The only comparisons that can be made between variable values are equality and inequality. There are no "less than" or "greater than" relations among the classifying names, nor operations such as addition or subtraction.

Statistical measures

The only kind of measure of central tendency is the mode; median and mean cannot be defined.

Statistical dispersion may be measured with various indices of qualitative variation, but no notion of standard deviation exists.

In this classification, the numbers assigned to objects represent the rank order (1st, 2nd, 3rd etc.) of the entities measured. The numbers are called ordinals. The variables are called ordinal variables or rank variables. Comparisons of greater and less can be made, in addition to equality and inequality. However, operations such as conventional addition and subtraction are still meaningless.

Statistical measures

The central tendency of an ordinally measured variable can be represented by its mode or its median, but mean cannot be defined.

One can define quantiles, notably quartiles and percentiles, together with maximum and minimum, but no new measures of statistical dispersion beyond the nominal ones can be defined: one cannot define range (statistics) and interquartile range, since one cannot subtract quantities.

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Interval measurement

The numbers assigned to objects have all the features of ordinal measurements, and in addition equal differences between measurements represent equivalent intervals. That is, differences between arbitrary pairs of measurements can be meaningfully compared. Operations such as averaging and subtraction are therefore meaningful, but addition is not, and a zero point on the scale is arbitrary; negative values can be used. The formal mathematical term is an affine space (in this case an affine line). Variables measured at the interval level are called interval variables, or sometimes scaled variables, as they have a notion of units of measurement, though the latter usage is not obvious and is not recommended.

Ratio measurement

The numbers assigned to objects have all the features of interval measurement and also have meaningful ratios between arbitrary pairs of numbers. Operations such as multiplication and division are therefore meaningful. The zero value on a ratio scale is non-arbitrary. Variables measured at the ratio level are called ratio variables.

Some level measuring, indicating and controlling instruments are illustrated below: Level Integral Part Of The Process Control. The Liquid Level Reference To a Datum Is An Important Measuring Parameter.

TUBULAR LEVEL INDICATOR MODEL SC / TLI / 301

Spink Controls has been involved in every aspects of liquid level measurement of liquids, with isolating valve to prevent accident. These level indicators are available in side and top mounted.

Operating Pressure / Temperature : 10Kg / cm2 / 100 C

Protection Channel : MS with Powder Coated/SS

Wetted Parts : MS / SS 304 / SS 316 / PP /PVC / HDPE

Glass : Heavy walled Borosilicate.

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REFLEX LEVEL INDICATOR MODEL SC/RLI/401

These are used for high pressure, high temperature, transparent liquid and corrosive liquids. Because of the property of reflection the transparent liquids turns black and makes easy to read.

Operating Pressure / Temperature : 40 Kg / cm2 / 3000 C

Wetted parts : MS / SS 304 / SS 316

Glass : Klinger / Maxos / Toughned Borosilicate

MAGNETIC LEVEL INDICATOR

The magnetic level indicator using a float Magnetically coupled to indicator. These are used for high pressure, high temperature, coloured and corrosive liquids.

SC / MLI / 501 : Follower Type Indicator SC / MLI / 502 : Bi-Coloured Rotating Type Indicator Operating Pressure / Temperature : 30 kg / cm2 / 2000C. Wetted Parts : SS 304 / SS 316 / PP Mounting : Side / Top. Additional Accessories : * Adjustable Alarm Switch, * Relay Control Unit

FLOAT AND BOARD TYPE LEVEL INDICATOR

These types of indicators are used for big storage tanks of height more than 2 meters up to 8 meters. The board is aluminum powder coated and screen printed. Wetted parts available in SS 304 / SS 316 / PP / PVC depending upon service condition.

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FLOAT TYPE LEVEL SWITCH MODEL : SC / LS / 601

Top mounted level switch for use with clear liquids of density 0.8 to 1.5 gm/cc. Measuring range up to 3 meters. Available in weatherproof and Flameproof enclosure, and number of set points.

Operating Pressure : 5 Kg / cm² Operating Temperature : 100° C

Material of Construction : SS 304/SS 316

MAGNETIC FLOAT SWITCH MODEL: SC / LS / 602

Float switches are side mounted in weatherproof / Flameproof housing with electric ON / OFF version.

Operating Pressure : 5 Kg / cm2

Operating : 1500 C

Material of Construction: SS 304/SS 316.

DISPLACER TYPE LEVEL SWITCH MODEL SC / LS / 603

These switches are used in most versatile level control ever designed. These offer advantages over float type switches in the control of agitated liquids paints, varnishes and heavy oil and foaming liquids.

Specific Gravity: 0.7 and higher. Pressure Rating : 40 Kg / cm2, Temperature Rating : 2000 C

Mounting: Top Mounted/Side Mounted.

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CONDUCTIVITY TYPE LEVEL CONTROLLER MODEL SC / LS / 604

These are available in weatherproof/Flameproof enclosure. These are used for conductive liquids with suspended solids. Mounting : Top

Process Connection : Flanged (as per customers requirement)

LEVEL CONTROLLER Model SC / LS / 606

Microprocessor based level controller can be connected to any of the switch depending upon the requirement. The output of this controller is potential free contact of the relay. These are available with one or more relay, maximum up to 5 relays.

Capacitance Type Level Indicator

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AUTOMATION

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4 – 20 mA

4 – 20 mA

Pneumatic Signal 0.02 – 1Kg/cm2

----------------

----------------

----------------

----------------

----------------

----------------

R Y B

U V W

4 – 20 mA

4 – 20 mA

20. CONTROLLLING PRESSURE THROUGH AUTOMATION

21. CONTROLLLING TEMPERATURE THROUGH AUTOMATION

…………………

…………………

…………………

…………………

…………………

…………………

………………….

Pressure Transmitter

Pressure Controller

P I

Temperature Transmitter

Temperature Controller

Thyristor Unit

RTD or Thermocouple

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4 – 20 mA

P

4 – 20 mA 4 – 20 mA

Control Valve

22. CONTROLLLING LEVEL THROUGH AUTOMATION

23. CONTROLLLING FLOW THROUGH AUTOMATION

…………………………………………………………..

…………………

…………………

…………………

…………………

…………………

…………………

………………….

P I

Level Transmitter

Level Controller

P

I

Flow Controller

Flow Transmitter

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IV CONCLUDING REMARKS Having undergone Summer Training in SRF Plant in Malanpur has indeed

been a most unique and rewarding experience.

Our effort at making a project report on “Measuring, Indicating &

Controlling Instruments in Industrial processes” has been most educative and

academically satisfying. We received our initiation to a real life work place

environment and it has been an unforgettable experience.