Piping dan Instrumentation Diagram (P&ID)merupakan skema dari ,jalur pipa,equipment, instrumentasi, control system,dari suatu sistem proses yang terdapat diOil Refinery,Chemical Plant, Paper Mill, Cement Plant, dll. Simbol-simbol yang terdapat dalam P&ID mewakili peralatan seperti actuator, sensor-sensor dan kontroler. P&ID menjelaskan secara detail mengenaiflow process(Diagram Alir), terkecuali parameter-parameter seperti temperatur, tekanan, dan besarnya arus tidak dapat dijelaskan dalam P&ID. Alat-alat process sepertivalve(katup), instrument,dan Saluran pipa diidentifikasikan dengan kode. Kode-kode tersebut berdasarkan ukuran, jenis cairan yang dialirkan, jenis sambungan pipa (Seperti dengan menggunakanBoltatauFlang), dan keadaan StatusValve(Normally CloseatauNormally Open).

Diagram P&ID pada suatu Process SystemP&ID dapat digambarkan dengan tangan (gambar biasa diatas kertas) atau dengan menggunakan komputer.Softwaredalam membuat P&ID untuk PC atau Mac, antara lain dapat menggunakan Microsoft Visio (PC), Omni Grafle (Mac), atau menggunakansoftwareyang didesain untuk P&ID yaitu Cadworx P&ID dari COADEBeberapasoftwareP&ID ini tidak menunjukan ukuran aktual dan posisi dari peralatan-peralatan seperti sensor,valve,danequipment,akan tetapi untuk menampilkan sebuah diagram hubungan dari suatu sistem process yang disimpan sebagai data elektronik dan dapat dilihat di PC.SoftwareCadworx P&ID dapat menyimpanDatabasedan menghasilkanReportequipment table listdari komponen-komponen / instrument yang terdapat dalam P&ID suatu process. Pada bagian berikutnya dari artikel ini kita akan membuat suatu P&ID dengan menggunakansoftwareCadworx P&IDRepresentasi dariLine ProcesspadaP&IDLine SymbolLineSymboldigunakan untuk menggambarkan hubungan antara unit-unit yang berbeda dalam sistem yang dikontrol. Tabel berikut di bawah ini merupakan Line Simbol yang pada umumnya sering digunakan.Tabel 1.Line SymbolDari table 1,Piping linemerupakan proses utama dimana pipa mengalirkan bahan kimia yang diidentifikasikan dengan menggunakan kode. Simbol linelainnya menjelaskan bagaimanasystemterhubung antara satu proses dengan proses lainnya,serta signal yang digunakan dalam sistem instrumentasi, sepertielectrical signal,pneumatic signal,data, dll.

Gambar 1Kode-kode yang terdapat padaPiping Linemenunjukan Diameter Pipa,FluidService, material, dan isolasi.Diameter pipa dalam Inch.Fluid servicememberi keterangan jenis fluida yang dialirkan. Materialmemberikan informasi mengenai bahan pembuat pipa. Sebagai contoh CS untukCarbon Steelataustainless steelSS.Pengunaan kode-kode pada Process Line sebagai contoh gambar 1, pada aliran pipa no 39 menunjukan pipa dengan diameter 4 Inch, dengan Fluid Service mengalirkan bahan kimia N, berbahan material CS (Carbon Steel) , dan tanpa insulasi (No Insulation)

Simbol untuk Valves

Simbol untukValves ActuatorSimbol untuk Fitting dan Representasi

Simbol untuk EquipmentInstrumentation SymbolKode-kode Instrumentasi yang tertera di P&ID adalah sebagai berikut, huruf pertama mengidentifikasikan parameter yang dikontrol, huruf selanjutnya mengidentifikasikan tipe perangkat control

Berdasarkan contoh diagram P&ID di atas,FT101, huruf pertama F mempunyai arti kode (berdasarkan kode ISA) yaituFlow. Huruf kedua T mempunyai artiTransmitter,kode FT101 dapat diartikan sebagaiFlow Transmitter,Lingkaran menunjukan FT101terpasang(mounted)diField Area,yang dihubungkan olehelectric signal(Garis putus-putus). Pada FIC101, berarti (Flow Indicator Controller), simbol berupa kotak dan lingkaran menunjukanFIC101, terletak diShared Control / Shared Displaysdan dapat diakses oleh operator

Huruf PertamaParameter yang dikontrol

AAnalysis

CConductivity

DDensity

EVoltage

FFlow Rate

ICurrent

LLevel

MMoisture(Humidity)

PPressure or Vacuum

TTemperature

VViscosity

Huruf SelanjutnyaTipe Peralatan Kontrol

AAlarm

CController

IIndicator

TTransmitter

VControl Valve

EElement

ICIndicator Controller

FCRatio Controller

RRecorder

HSHand Switch

HVHand Valve

QTotalizer

IQIndicating Totalizer

XVSolenoid Valve

YCalculation

FYRatio Callculation

SLSwitch Low

SHSwitch High

ALAlarm Low

ALLAlarm Low Low

AHAlarm High

AHHAlarm High High

Process and Instrumentation Symbols - EquipmentsPumps and tanks come in a variety of designs and shapes.

Pumpsis a mechanical device using suction or pressure to raise or move liquids, compress gases, or force air into inflatable objects such as tires. The symbols for pumps may closely resemble those for compressors.Centrifugal pumpis rotodynamic pump that use a revolving impeller to add to the force and pressure of fluids.Gear pumpprovide continuous, non-pulsing flow making it ideal in chemical installations.Sump pumpis widely used to remove accumulated water from a sump pit or other location.Vacuum pumpis used to improve the efficiency of steam heating systems in many ways. The most important consideration is the rapid and efficient removal.Screw pumpis the Archimedes screw pump that is still used in irrigation and agricultural applications.Tankis used to store process fluids of various types, under different process conditions.Onion tankis an open top collapsible bladder designed for use as a mobile storage solution when recovering contaminants.Compressoris a mechanical device that takes in a medium and compresses it to a smaller volume. A mechanical or electrical drive is typically connected to a pump that is used to compress the medium.Axial compressoris widely used in gas turbines, such as jet engines, high speed ship engines, and small scale power stations.Reciprocation compressoris typically used where high compression ratios are required per stage without high flow rates, and the process fluid is relatively dry.

Rotary compressoris a type of gas compressor which uses a rotary type positive displacement mechanism.Mixingis a device that combine or put together to form one substance or mass.Mixing vesselis a container that is used to blend several components together.Heat exchangeris a device used to transfer heat energy between two process flows. Heat exchangers transfer heat energy through conductive and convective heat transfer.Cooling towerstransfer heat energy to the outside air through the principle of evaporation.Cooleris a device, container or room that cools air through the evaporation of water or keeps cool.Turbine driver is used to drive pumps and fans at petrochemical plants.Furnaceis a device for heating a continuous current of air by means of a fire contained within the apparatus and without mingling the fresh air with the products of combustion.Boileris a closed vessel in which water or other fluid is heated.

Oil burnerlis engineered from the ground up exclusively to burn waste oils.Automatic stokers used to supply hot water to central heating systems.Plate toweris used widely in many processes and industrial applications.Packed toweris a type of packed bed used to perform separation processes.Elevatoris used to control the position of the nose of the aircraft and the angle of attack of the wing.Mixing reactoris widely used in the chemical industry to promote mixing.Process and Instrumentation Symbols - Valves

Gate valveis a device used to control the flow of liquids and gases.Check valve, also known as one-way valve, is to prevent the line of medium back.Globe valveis a mechanism used to control or stop the flow of liquid or gas through a pipe.Ball valveis a valve with a spherical disc, the part of the valve which controls the flow through it.Butterfly valveis installed between two flanges using a separate set of bolts for each flange.Angle valveis oriented at an angle 90 deg of gate valve.Process and Instrumentation Symbols - Piping LinesProcess flow diagrams use special piping lines to represent how signals are transmitted between equipments. These symbols are used to identify how the instruments in the process connect to each other. And what type of signal is being used. (electrical, pneumatic, data, etc)

All lines to be fine in relation to process piping lines.Major pipelineis used to connect the equipment in any position.Major Straight lineis sued to connect the equipment in the same horizontal or Vertical position.Process connectionhelp create the process flow between equipments. Double click process connection to edit description.

Process and Instrumentation Symbols - InstrumentsProcess Flow Diagram use symbols and circles to represent each instrument and how they are inter-connected in the process.

These instrumentation symbols can easily change types by clicking the quick action button while designing.