Good Stuff Consultancy

We supply
ointment manufacturing plant.
Cream, toothpaste, Gel manufacturing plant
Preparatory vessels
Stainless steel reactors
Storage tanks
Variable speed 🚄 agitator
Automation in preparation vessels
Dispo homogenizer ( high speed)
Homogenizer / Dispersing machines
Pharmaceutical process and packaging machinery.

@ Good Stuff Concept.
1, Omila street Onireke Rd, Opposite Ojo military cantonment 🪖 Amuwo-odofin,
Lagos state.
Tel or Whatsapp 08062928450

Flow Measurement in Liquid and Gas 👍
💧 Liquid Flow Measurement
◾ Liquids are incompressible—their volume doesn’t change much with pressure.

◾ That’s why, even if there’s a pressure drop across a valve, the flow rate (in M³/hr) remains the same before and after the valve.

◾ In the image above, we see:
▪️ Inlet Pressure: 18 Kg/cm²
▪️ Outlet Pressure: 12 Kg/cm²
▪️ Flow Rate: 500 M³/hr → 500 M³/hr

✅ Conclusion: Volumetric flow remains constant for liquids, despite pressure drops.

💨 Gas Flow Measurement
◾ Gases are compressible—they expand as pressure drops.

◾ After passing through a control valve, gas expands, causing the volume to increase.

◾ In the image:

▪️ Inlet Pressure: 18 Kg/cm²
▪️ Outlet Pressure: 12 Kg/cm²
▪️ Flow Rate: 500 M³/hr → 750 M³/hr

⚠️ Important: Even though mass flow might be conserved, volumetric flow increases downstream due to expansion.

📏 Why It Matters
Flow meters must account for compressibility when measuring gas.

Engineers often use mass flow transmitters or corrected flow readings for gases, while volumetric transmitters work well for liquids.

Why a Siphon Tube Is Used in a Pressure Gauge❓
👉 In industrial settings where pressure measurement involves high-temperature fluids—especially steam—siphon tubes play a critical role in protecting pressure gauges. Though they may seem like a simple coil of pipe, their purpose is essential for ensuring both accuracy and longevity of the instrumentation.
👉 What Is a Siphon Tube?
A siphon tube is a curved or coiled metal tube installed between a pressure gauge and a pipeline carrying hot v***r (usually steam). It’s commonly seen in the form of a pigtail (circular coil) or U-shape, made from materials like stainless steel, brass, or carbon steel.
👉 Purpose of a Siphon Tube in Pressure Gauges
1. Protects the Gauge from High Temperature
Steam, especially in boiler systems, can reach very high temperatures. If this steam enters the pressure gauge directly, it can damage internal components, affect readings, or even cause gauge failure.
✅ Siphon tubes act as thermal barriers, allowing steam to condense into water before reaching the gauge.
2. Creates a Water Seal
The coiled portion of the siphon tube holds a small amount of water (condensate), which forms a protective liquid barrier between the hot steam and the gauge.
This trapped water absorbs the heat and prevents direct contact of steam with the sensitive parts of the gauge.
3. Ensures Accurate Readings
Exposing a gauge directly to high-temperature steam can alter pressure readings due to thermal expansion or deformation of parts.
✅ The siphon ensures temperature stabilization, helping the gauge maintain accurate pressure measurements over time.
4. Increases Lifespan of the Gauge
Constant exposure to high heat and pressure can shorten the operational life of a pressure gauge.
✅ Siphon tubes minimize thermal stress, extending the life of the gauge and reducing maintenance and replacement costs.
👉 Where Are Siphon Tubes Used?
◾ Steam boilers and turbines
◾ Power plants
◾ Refineries and chemical processing units
◾ Heating systems
◾ High-pressure steam pipelines
👉 Types of Siphon Tubes
1️⃣ Pigtail Siphon – Circular coil, ideal for vertical mounting.
2️⃣ U-type Siphon – U-shaped curve, suitable for horizontal mounting.
3️⃣ Straight Siphon with Loop – Used in tight spaces or where custom geometry is needed.
Each type serves the same purpose but is selected based on orientation, pressure rating, and space constraints.

Labeled Diagram of Boiler Mountings Essential Components and Functions!

1. Safety Valve
Location: Top of the boiler
Function: Automatically releases excess steam if pressure exceeds safe limit. Prevents boiler explosion. Usually two are fitted.

2. Air Purge Valve (Air Vent Valve)
Location: Top of the boiler
Function: Removes trapped air during filling and starting. Prevents air locks and ensures proper steam circulation.

3. Pressure Gauge
Location: Top, connected via a pipe
Function: Continuously displays the internal steam pressure so the operator can monitor safe working conditions.

4. Water Level Gauges (Water Level Indicators)
Location: Side of the boiler
Function: Shows the exact water level inside the boiler. Prevents low-water (risk of overheating) or overfilling. Two are fitted for safety.

5. Main Feed Valve (Feed Check Valve)
Location: Feed water inlet
Function: Allows feed water into the boiler but prevents backflow of hot water/steam into the feed line (non-return valve).

6. Check Valve
Location: Feed water line
Function: Additional non-return valve as backup to the main feed check valve.

7. Scum Blowdown Valve
Location: Near the normal water level
Function: Removes oil, scum, and floating impurities from the water surface to keep steam clean and prevent foaming.

8. Bottom Blowdown Valve
Location: Lowest point of the boiler
Function: Rapidly removes settled sludge, mud, and sediment to prevent scale buildup.

9. Blowdown Dip Pipe
Location: Inside the boiler, extending to the bottom
Function: Ensures the bottom blowdown valve can effectively remove heavy sediments from the mud drum.

10. Qbd Valve (Quick Blowdown Valve)
Location: Near bottom blowdown line
Function: Fast-opening valve for rapid or emergency blowdown of the boiler.

For all your industrial and agro allied machines design and construction,. Meet us Good Stuff Consultancy
1, Omila road, Off Onireke Rd,
Opposite Ojo Military cantonment 🪖,
Lagos state, Nigeria 🇳🇬

Call or Whatsapp 08062928450
Email - [email protected]