Superheated Steam Properties Calculator

Enter Pressure with either Temperature or Degree of Superheat. Calculates v, ρ, h, s, u and heat capacities (Cp, Cv, k). Exports to Excel with live formulas.

Input Mode

Pressure + Temperature Pressure + Superheat (ΔT)

Pressure

bar(a) kPa(a) MPa(a)

Valid: 0.06–221 bar(a) Temperature

°C K

≥ T_sat at given P Degree of Superheat (ΔT)

°C

ΔT ≥ 0 (final T = T_sat + ΔT)

Calculate Export Excel Reset Copy

Saturation Temperature at P (T_sat)

–

Actual Temperature (T)

–

Degree of Superheat (ΔT)

–

Specific Volume v (m³/kg)

–

Density ρ (kg/m³)

–

Enthalpy h (kJ/kg)

–

Entropy s (kJ/kg·K)

–

Internal Energy u (kJ/kg)

–

Isobaric Heat Capacity C_p (kJ/kg·K)

–

Isochoric Heat Capacity C_v (kJ/kg·K)

–

Heat Capacity Ratio k = C_p/C_v

–

Formula & correlation notes

• Saturation (for T_sat): IAPWS Wagner-type p(T); for T from P use Newton with central derivative.
• Ideal gas: v = R·T/P (with P in bar → ×100 to kPa); ρ = 1/v.
• Enthalpy (superheated): h ≈ C_p·T + h₀ with h(100 °C,sat)=2676 kJ/kg ⇒ h₀ = 2676 − C_p·T_ref.
• Entropy (superheated): s ≈ s_g,ref + C_p·ln(T/T_ref) − R·ln(P/P_ref).
• Internal energy: u = h − P·v (P in kPa, v in m³/kg → kJ/kg).
• Heat capacities: C_v = C_p − R; k = C_p/C_v. (Single-average C_p used.)

The post Superheated Steam Properties Calculator appeared first on Chemical Engineering Site.

Saturated Steam Properties Calculator

Enter either Temperature or Pressure. Calculates saturation and properties: v_g, ρ_g, v_f, ρ_f, h_f, h_fg, h_g, s_f, s_fg, s_g. Export to Excel — changing inputs there updates outputs automatically.

Input Mode

By Temperature By Pressure

Temperature

°C K

Valid range: 0–≈374 °C (273.15–647.096 K)

Pressure

bar(a) kPa(a) MPa(a)

Valid range: 0.006–221 bar(a)

Calculate Export Excel Reset Copy

Saturation Temperature (T_sat)

–

Saturation Pressure (P_sat)

–

Specific Volume (Vapor) v_g (m³/kg)

–

Density (Vapor) ρ_g (kg/m³)

–

Specific Volume (Liquid) v_f (m³/kg)

–

Density (Liquid) ρ_f (kg/m³)

–

Enthalpy (Liquid) h_f (kJ/kg)

–

Latent Heat h_fg (kJ/kg)

–

Enthalpy (Vapor) h_g (kJ/kg)

–

Entropy (Liquid) s_f (kJ/kg·K)

–

Entropy of Vaporization s_fg (kJ/kg·K)

–

Entropy (Vapor) s_g (kJ/kg·K)

–

Formula & correlation notes

• Wagner saturation (IAPWS): ln(p/pc) = (Tc/T)·(a₁τ + a₂τ^1.5 + a₃τ³ + a₄τ^3.5 + a₅τ⁴ + a₆τ^7.5), τ = 1 − T/Tc
• Ideal gas for v_g: v_g ≈ R·T/p; ρ_g = 1/v_g
• Watson latent heat: h_fg(T) = h_fg,ref·[(1−T/Tc)/(1−T_ref/Tc)]^0.38
• h_g: h_g ≈ c_p,g·T + h₀ (2676 kJ/kg at 100 °C); h_f=h_g−h_fg
• s_g: s_g ≈ c_p,g·ln(T/T_ref) − R·ln(p/p_ref) + s_g,ref; s_fg=h_fg/T; s_f=s_g−s_fg
• Liquid ρ_f: Kell (≤100 °C) + smooth fit above 100 °C; v_f=1/ρ_f.

The post Saturated Steam Properties Calculator appeared first on Chemical Engineering Site.

P&ID is the diagram which shows the interconnection of process equipment and the instrumentation used to control the process.

The uses of P&ID are as follows

• P&ID is the basis for developing the control systems in the chemical process.
• It helps in Equipment design and Piping design and also serves to estimate the capital cost.
• Hazard and Operability (HAZOP) Study is performed during the design stage with the help of P&I diagram.
• It will assist in preparing Commissioning procedure, Pre-Startup Safety Review, Standard Operating Procedures for Startup, Normal operation and Shutdown.
• It also assists in preparing Plant Operating manual
• Control narrative and Interlock narratives will be prepared by having P&ID as the basis.
• It will help to prepare the Instrument Index and other will serve as a reference for creating other datasheets.
• It acts as a beacon for newbie process engineer in a Chemical Industry.
• P& ID also helps in Incident investigations to find out What Went Wrong through root cause analysis.
• It helps in evolving maintenance procedures of equipment. It helps to visualize the interconnecting systems with the equipment and planning for proper isolation can be done.

What is the difference between P&ID and PFD?

Process Flow Diagram (PFD) is used for indicating the general flow of process and equipment. It helps to visualize the overall process of the in a chemical plant.

PFD will contain main process piping, Main equipment number, Equipment Name, Flow directions, Major bypass lines, Critical Control Valves that affects the process, Stream Number, Stream Designation, Process parameters like operating temperature, operating pressure, flow rate, Composition and heat duty of heat transfer equipment.

PFD will not contain Piping size and classification, Process control Instrumentation details like Transmitters, Control valves, Design Temperature and Pressure, Material of Construction of Equipment and piping, Mechanical Valves for isolation, Vents and Drains, Relief valves & Safety Valves.

P&ID will contain Equipment number, Equipment Name, Process and Utility piping, Piping size and classification, Instrumentation details like Transmitters, Control valves with their numbers, Control input and output, Annunciation input, SIS input, solenoid valves, On-off valves, Motorised valves, Relief valves, All Mechanical valves Miscellaneous items like strainers, Vents, drains, Silencers, standpipes etc, Vendor items and interfaces, Equipment design pressure, Temperature and Material of Construction, Free draining requirements etc. P&ID will also have general notes that will assist during Detailed Engineering, Erection and Commissioning phase. Though it is not an exhaustive list, Our P&ID Check list in the trailing part of this post will help you to explore in detail about Piping and Instrumentation Diagrams.

P&ID will not contain Operating parameters, Equipment elevation details, Elbows, MTO, etc. It is not drawn to scale and hence geometric accuracy can not be expected out of P&ID.

P&ID Symbols

The instrumentation symbols used in P&ID are as per ISA-S5.1 standard –  Instrumentation Symbols and Identification. For Symbols of chemical apparatus and equipment normally ISO, JIS, DIN or PIP standards are followed. 

What are the Softwares available to make P&ID?

There is some renowned P&ID software available that can be used online and offline. It saves time in creating a P&ID with the help of simple user-friendly tools available in them. Some of them are,

Autocad is one of the worlds leading design and drafting software used by many of the Chemical Process Design companies for preparing P&ID. 2D and 3D design drawings also can be made out of it.

MS-Visio is very useful offline software for Chemical Engineers to prepare PFD, P& ID and other diagrams in a simple way by just dragging and dropping the symbols.

Lucidchart is an online software for preparing P&I diagrams in a fast manner. Anyone can make the drawing with a drag and drop option. This simple and efficient software also has the functionality to import and export from MS- Visio.

P&ID Review Checklist

Chemical Engineer must review the P&ID before finalizing them for implementation. Our exhaustive Excel P&ID Review Checklist helps to review the P&ID to make it fit based on Safety, Erection, Commissioning and Operation aspects.

Download the P&ID Review Checklist as Excel file

If you find anything missing in our checklist, feel free to mail to us so that we will add them.

The post Piping and Instrumentation Diagram – P&ID appeared first on Chemical Engineering Site.

PFD and P& ID Preparation in Visio

Process Flow Diagram (PFD) and Piping and Instrumentation diagram (P& ID) can be prepared with the help of this software easily. The available tools for creating the diagram is customized and made available as icons under the topics Equipments – General, Heat Exchangers, Pumps, Vessels, Instruments, Pipelines, valves & Fittings. Once can also use the search box to find out the needed equipment. Other simple customizations can be done like any other MS – Office software like Changing the color, Font size and Inserting symbols which is helpful in creating colorful PFD/ P& ID’s for presentation purpose. It is possible to save the diagrams as VISIO files or simple images. The other use is we can simply copy the equipments from VISIO and paste it as image wherever we need.

Other Applications of VISIO

Organization charts for the department or for an Industry can also be effectively created with the help of VISIO. Gantt Charts can be created by using MS – VISIO to schedule project tasks and communicate them visually to team members. Program Evaluation and Review Technique (PERT) chart can be prepared which is a useful tool for Project managers. Brainstorming diagrams available in MS-VISIO Swill help to conduct a brainstorming session in effectively capturing and organizing the ideas.

It also helps to prepare Plant layout and site layout. Cause and effect diagrams which is also known as fishbone or Ishikawa diagrams can be made using VISIO. This will Show factors and causal relationships in a given situation. Fault tree analysis diagrams show and analyzes faults in processes. Basic electrical diagrams, Circuits and logic diagrams, Industrial control systems diagrams will be helpful for creation of circuit diagrams and other Interlock diagrams. These will be very useful for Electrical engineers and Instruments Engineers also.

Hope this review will be helpful to understand the uses of MS- VISIO. If so, Share this with friends

The post MS- VISIO for Chemical Engineers appeared first on Chemical Engineering Site.