فيه ٣ حاجات هتسمع عنهم كتير لو انت involved ف مجالنا أي كان تخصصك ، أو تخصص شركتك سواء engineering أو production BFD - PFD - P&ID

بوست ف اللذيذة وأنت نشيط الصپح

فيه ٣ حاجات هتسمع عنهم كتير لو انت involved ف مجالنا أي كان تخصصك ، أو تخصص شركتك سواء engineering أو production 

BFD - PFD - P&ID 

وانا النهاردة جايلك بشرح مبسط جدا لكل واحد فيهم 

تعريفه ، الغرض منه وهكذا علشان نقرأ مع بعض ، و ٣ صور للتعبير عن كل واحد فيهم وتعرفة physically شكله أيه 

let's begin ⤵️⤵️⤵️⤵️⤵️⤵️⤵️⤵️⤵️⤵️⤵️

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1️⃣-BFD (Block Flow Diagram)

↪️process drawing used tosimplify the basic structure of a system.

↪️the simplestform of the flow diagrams used in the industry.

↪️Blocks represent anything from a single pieceof equipment to an entire plant.

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2️⃣-PFD(Process Flow Diagram) 

↪️diagram commonlyused in engineering to indicate the general flow of theplant process.

↪️displays the relationship betweenmajor equipment of a plant facility and does not showminor details such as piping details and designations.

↪️Process flow diagrams of a single unit process will include⤵️⤵️⤵️

☑️Major process piping

☑️Major bypass & recirculation lines

☑️Major equipment symbols, names, and

☑️identification numbers

☑️Process flow directions

☑️Major control loops

☑️Interconnections with other systems

☑️Stream Identification

☑️Heat & Mass Balance

↪️PFDs generally do not include⤵️⤵️⤵️

☑️Piping class or piping line numbers

☑️Pipe size

☑️Instrumentation

☑️Minor bypass lines

☑️Isolation and shut-off valves

☑️Maintenance vents and drains

☑️Relief and Safety Devices

☑️Pipe fittings and flanges

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3️⃣-P&ID(piping & instrumentation diagram)

↪️It is a pictorialrepresentation of the piping, equipment, instrumentation,and control devices. 

↪️P&ID preparation is initiated during

FEED and is further updated during detail engineering.

↪️P&IDs are updated according to vendor data, design reviewcomments, HAZOP recommendations, and as-builtchanges.

↪️P&ID shows the interconnection of process equipment andthe instrumentation used to control the process. 

↪️In theprocess industry, a standard set of symbols is used toprepare drawings of processes. 

↪️The instrument symbolsused in these drawings are generally based on the

International Society of Automation (ISA) Standard S5.1

↪️CAD system is used to develop the P&IDs.

↪️Most details that are available from other types ofdocumentation (e.g., instrument loop diagrams,vessel data sheets) are not recommended forinclusion on P&IDs.

↪️P&ID shows equipment with simple outline

representation.

↪️Equipment is not drawn to scale, howeverequipment relative to one another both in size andgeneral orientation must be maintained.

↪️P&ID shows nozzles on equipment, including

spares, as single lines.

↪️P&ID indicates nozzle sizes unless the size is

implied by piping connections.

↪️P&ID shows equipment item number and

title/service as a minimum.

↪️P&ID indicates internals for equipment as dashedlines. Details of internals that have no significantbearing on the piping design and layout orequipment operation are omitted.

↪️P&ID indicates auxiliary system requirements forindividual pieces of equipment (e.g. lube oil systems, seal flush systems, turbine gland leak-offpiping, sample systems) on auxiliary P&IDs.

↪️P&ID indicates jacketing requirements for

equipment and jacketing/tracing requirements forpiping.

↪️P&ID indicates the type of insulation (e.g.,

personnel protection, heat conservation) for

equipment as part of the equipment data.

↪️P&ID indicates insulation thickness where

applicable.

↪️P&ID indicates a piping serial number and piping class.

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Industrial Automation System Architecture Reference Modelby Editorial StaffArchitectures represented are based on the IEC 62443 Industrial Automation and Control Systems (IACS) architecture reference model. The basic model consists of 5 levels.

Table of Contents

• System Architecture
  • Level 0:
  • Level 1:
  • Level 2:
  • Level 3:
  • Level 4:
• Architecture Diagram Notations
• 
  
  
• Figure 1: An Architecture reference model

Level 0:

It is the Process or equipment under control

Level 1:

It includes the Controllers/PLCs that provide basic control, safety and protection functions

Level 2:

It includes supervisory control functions and includes devices such as HMIs, Operating workstations, Engineering Workstations, Historians, Application Servers, Engineering Databases, etc.

Level 3:

It includes the operations management functions such as domain controller, backup server, antivirus and patch management, etc.

Level 4:

It refers to the Enterprise systems

Architecture Diagram Notations

The architecture diagrams show a very simplistic view of system architectures.

These architecture diagrams illustrate specific ways to perform remote access.

The local “IACS” network is represented simplistically to ease the understanding (the actual internal IACS architecture will vary and specific integration and interfaces between the diverse IACS usually required in most implementation is not included or represented in these diagrams).

Dataflows between the different functions are represented by arrows. The direction of the arrows show the outbound or inbound characteristic of the dataflow, but do not represent network sessions.

HMI is used as a generic term to refer to any Human Machine Interface or workstation (Operator, maintenance or engineering workstations, for BPCS, SIS, or Packages).

Local station refers to any workstation or server located at the production site that is used to transfer data or is accessed from a remote site.

The DMZ firewall is represented as a single symbol but can be implemented as a pair of physical firewalls.

The tunnel shown on the diagram refers to a secure tunnel, that can be set up with different technical solutions (e.g., IPSec).

These architecture Diagrams do not show the full detail of all possible types of local networks. Depending on the system vendor solution, some networks that are represented as the separate networks (such as control and HMI network) may be a single network.

Mohamed abd elgawwad 

Flow Measurement

Thermal mass flowmeter

Flow MeasurementInstrumentation

Thermal mass flowmeter

What are Mass flowmeters?

A Mass flowmeter measures the amount of fluid pass through the pipe. Mass flow measurement gives a more accurate account of fluids and is not affected by density, pressure and temperature (unlike volumetric measurements).
Although most meters can infer mass flow rate from volumetric flow measurements, there are a number of ways to measure mass flow directly.

 

Thermal Mass Flowmeters:

Thermal mass flowmeter work on the principle of loss of temperature when a fluid stream passes across it.

The two main types of thermal mass flow measuring devices are:

• Thermal Anemometer
• Temperature rise flowmeter

Thermal anemometer:

The thermal anemometer works by measuring the heat dissipation from a probe inserted in the line. The amount of heat taken from the probe is dependent on the fluid velocity and density but is also a direct measure of the mass flow rate. The temperature is also measured by the calculation. They are also referred to as ‘Hot wire probes’.

The probe can either be constant current or constant temperature.

In the constant current type, a fixed current is passed through the probe which causes heating in the probe. As the flow rate varies, so does the amount of heat taken from the probe and hence the temperature changes. The temperature is measured to derive the flow.

For the constant temperature type, a feedback loop is required to maintain a constant temperature. As the change of flow affects the temperature, the current needs to be regulated to maintain probe temperature. The flow rate is determined by the power required to heat the probe. The constant temperature devices have a faster response to flow changes.

The temperature probe must protrude into the flow stream, and therefore may be easily damaged by corrosion and erosion. In addition, the robustness of the system is compromised by the protrusions into the fluid stream, increasing the chances of leakage.

However thermal anemometer has fast response times, < 0.5milliseconds.

 

Temperature rise flowmeter:

Temperature rise flowmeters work on the principle of heating the flow stream. By heating the flow stream at one point, the temperature can be measured both upstream and downstream of the heating point. Calculating the difference between the temperatures gives information about the flow rate.

This method requires the measurement of actually heating the process fluid. It is therefore limited to gas applications at low flow rates.

As with the hot wire probe, the temperature sensors and the heater must protrude into the flow stream, and therefore may be easily damaged by corrosion and erosion. Also, the robustness of the system is compromised by the protrusions into the fluid stream, increasing the chances of leakage.

There are external fixing types of temperature rise flowmeter for large pipelines:

External fixing provides Non-contact, non-intrusive sensing No obstruction to flow and Reduced maintenance.

Advantages:

• Thermal flowmeters are used to measure gas with low pressure
• Used measure low flow
• These flowmeters are frequently employed for monitoring and controlling of mass-related processes like chemical reactions.
• They offer good rangeability

Disadvantages:

• Practically for gas only.
• Power requirement execessive in large pipelines.
• Accurate field calibration is difficult.

Serial Communication

 Serial Communication

.
📌بالنسبة لل RS485 و RS232 دول بيستخدموا voltage signal علشان نقل البيانات
📌ال RS232 مقدرش احط اكتر من جهاز علي نفس network واقصي مسافة حوالي 50 متر
📌سرعة نقل البيانات 20kbs وكمان بيقابلني مشاكل noise


📌ال RS485 بيوصل لمسافات اطول حوالي 1200 متر بسرعه بيانات 90kbs واقصي سرعه عند 6 متر بتوصل 100Mbs
📌بستخدم 2wires في حالة اني شغال half duplex او 4wires لو اشتغلت full duplex وهنا جهاز مmaster والباقي slaves
📌بيحصل avoid لل noise بسبب استخدام differential signal كمان ممكن استخدم shielding للكابل علشان امنع الnoise


📌اما 20mA current loop بيستخدم current signal وطبعا الcurrent بيبقي افضل من ال volt في المسافات الطويلة
📌بيوصل ل 600 متر بسرعة بيانات 19.2kbs ودي سرعه بطيئة
📌مفيش standard علشان كدا لازم تدخل في التفاصيل الفنية للدايره بتاعتك وتفهمها وتختبرها
📌بيستخدم 2wires للارسال وغيرهم للاستقبال

1. What is CV?

 Cv is the Valve Coefficient, and is a measure of the capacity of a valve, which takes account of its size and the natural restriction to flow through the valve. Using published formulae it is possible to calculate the Cv required for an application. By comparing this calculated value with the Cv capacities of different valves it is possible to select a suitable size and type of valve for the application. Common Definition of CV

 

The Cv of a valve is the quantity of water in US gallons at 60 °F that will pass through the valve each minute with a 1 psi pressure drop across it. 

The Kv value is the metric equivalent in m3/hr with 1 bar pressure drop

Cv = 1.15 x Kv. The capacity of each valve can be expressed in terms of Cv - the value being determined experimentally in most cases. Using formulae developed empirically it is possible to calculate a Cv requirement for an application. By comparing the two figures it is possible to select the correct size of valve for the application. It is important to remember that the formulae and the valve Cv values are not exact, but are to be used as a guide. The most commonly used formulae are those supported by the Instrument Society of America (ISA). Simplified Liquid Service. C q G P v f e = ⋅ 1 1. 6 ⋅ ∆ Effective pressure drop is the smaller of (P1-P2) or ∆Pchoked P1-P2 is the actual Pressure drop ∆Pchoked = Fl²(P2-Pv) Where : Pv = Vapour pressure Fl = Pressure recovery factor Where : Cv is Valve Coefficient : Flow rate in m³/hr : Gf is Specific Gravity at the flowing temperature : ∆Pe is the effective pressure drop in Bar 1

Flow Measurement

Annubar flowmeter operation

Annubars are sometimes called average pilots and contain multiple pressure taps to “average” the flow; this is to try to compensate for a non-ideal flow profile.

The averaged pitot tube is inserted through the pipe as shown below. One side of the bar has pressure taps facing the flowing fluid and engaging in an “average” chamber that measures the total (ie, static + dynamic) pressure of the fluid.

There may be a single port or multiple outlet ports on the opposite side of the bar to measure the low static pressure in the downstream region.

The difference between the total pressure and the static pressure is effectively a measure of the height of the fluid velocity, which together with the area of the pipeline allows determining the volumetric flow.

 

 

Principle of Annubar operation:

The Annubar primary flow element is a device that is used to measure the flow of a liquid, gas or vapor that flows through a pipeline. It allows flow measurement by creating a differential pressure (DP) that is proportional to the square of the fluid velocity in the pipeline, according to Bernoulli’s theorem. This DP is measured and converted to a flow rate using a secondary device, such as a DP pressure transmitter.

The flow is related to DP through the following relationship.

where:

Q = Flow Rate

K = Annubar Flow Coefficient

DP = Differential Pressure

The Annubar generates a DP by creating a blockage in the pipeline and acting as an obstruction to the fluid. The fluid velocity decreases and stops as it reaches the front surface of the Annubar sensor, creating the impact / high pressure.

The Annubar detects the impact pressure using a DP transmitter.

As the fluid continues around the Annubar sensor, it creates a lower velocity profile on the back of the sensor, creating the low / suction pressure downstream of the Annubar. The individual ports, located on the back of the Annubar sensor, measure this low pressure. Working on the same principle as high pressure, an average low pressure is maintained at the low pressure that is connected directly to the transmitter for measurement.

The resulting differential pressure is the difference between the impact pressure reading (high) and the suction pressure reading (low) as seen below.

DP = PH – PL

where:

PH = High Pressure

PL = Low Pressure

The measured DP is used to calculate the flow rate.

Advantages:

• It can be inserted through a small opening.
• It can be used to sample the velocity at several points.
• Minimum obstruction that means less pressure drop

 

Turbine mass flowmeters

Impeller-Turbine Mass Flow Meters:

The impeller, turbine type mass flow meter uses two rotating elements in the fluid stream, an impeller and a turbine. Both elements contain channels through which the fluid flows.

The impeller is driven at a constant speed by a synchronous motor through a magnetic coupling and imparts an angular velocity to the fluid as it flows through the meter.

The turbine located downstream of the impeller eliminates all the angular momentum of the fluid and, therefore, receives a torque proportional to the angular momentum.

This turbine is constrained by a spring that deflects through an angle that is proportional to the torque exerted on it by the fluid, which gives a measure of mass flow.

Twin-Turbine Mass Flow Meter:

In this instrument two turbines are mounted on a common shaft.

As shown in the above figure, a twin-turbine mass flow meter in which two turbines are connected with a calibration torsion member. A reluctance type pick up is mounted over each turbine and a strong magnet is located in each turbine within the twinturbine assembly.

Each turbine is designed with a different blade angle; therefore, there is a tendency for the turbines to rotate at different angular speeds.

However, since the movement of the turbines is restricted by the coupling torque, the entire assembly rotates in unison at an average speed, and an angular phase shift between the two turbines develops. This angle is a direct function of the angular momentum of the fluid

The angular momentum is a function of mass flow. In the double turbine assembly, the turbines are not restricted by a spring, but the torsion member that holds them together is twisted. Therefore, the angle developed between the two turbines is a direct function of the torsion or torsion exerted by the system.