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**Optimizing Tube Velocity in Heat Exchangers** When it comes to heat exchanger design, tube velocity plays a critical role—impacting not only heat transfer efficiency but also fouling, corrosion, pressure drop, and even equipment lifespan. Why Tube Velocity Matters: For most fluids, higher tube velocities improve heat transfer by enhancing the inside heat transfer coefficient. But exceeding recommended velocities can lead to erosion, especially in abrasive or high-solid applications. On the flip side, low velocities increase the risk of laminar flow, resulting in fouling and reduced efficiency. The goal? Keep tube velocity optimized to maintain turbulent flow without risking damage. Key Considerations for Velocity Control: Fluid Characteristics: The ideal velocity varies with fluid type, temperature, and suspended solids. Material Limits: Each material has a safe velocity range, from 6 ft/sec for carbon steel to 20 ft/sec for Inconel. Exceeding these can erode protective oxide layers, increasing corrosion risk. Water Challenges: Seasonal changes in water source composition (e.g., river vs. cooling tower water) affect design. Lower flows during colder months may increase fouling, while higher flows could cause erosion. Whether you're in the design phase or assessing operations, understanding these dynamics can prevent costly downtime and extend heat exchanger life. Check out the full article for a deeper dive into best practices. #HeatExchangers #IndustrialEfficiency #ProcessEngineering #RefineryOperations #OilAndGas #CoolingWater #CorrosionControl #FoulingMitigation #WaterChemistry #ChemicalEngineering #PlantOptimization #OperationalExcellence #AssetIntegrity #MaintenanceEngineering #PetrochemicalIndustry #FlowDynamics #EquipmentReliability #ThermalEfficiency

💡 Vapor Belt: A Key Ally in Heat Exchanger Design Today, I want to share a little-known element that can make a significant difference in heat exchanger projects: the Vapor Belt. 🔹 What is the Vapor Belt? As the name suggests, it’s a “belt” external to the main shell of the equipment. It is designed to reduce the fluid velocity at the heat exchanger's inlet, preventing issues such as vibrations, erosion, or damage to the tubes. 🔹 Why use the Vapor Belt? In cases where the fluid enters at high velocity, baffle plates are often used to distribute the flow. However, these plates have limitations: - They can occupy several rows of tubes, reducing thermal efficiency and increasing equipment costs. - Even with baffles, the high fluid velocity can still cause unwanted vibrations in the tubes. With the Vapor Belt, we can: - Reduce the fluid velocity at the inlet evenly. - Minimize or eliminate the need for baffle plates. - Protect the tubes from vibration and premature wear. 🔧 How does it work? The Vapor Belt is installed around the main shell and features strategically calculated openings to reduce the fluid velocity at the inlet. This allows for smoother and more uniform flow distribution, improving the equipment's performance and durability. 📷 Below is a photo of a project where I used the Vapor Belt, highlighted in blue on the shell. A simple yet highly effective solution that enhances the efficiency and safety of the equipment. 👉 Have you heard of the Vapor Belt before? Share your experiences or questions in the comments! #ThermalEngineering #HeatTransfer #VaporBelt #IndustrialInnovation #EnergyEfficiency #ProcessEngineering

Water ingress can cause significant damage to steam turbines, including: 1. Mechanical damage: Wet steam can cause erosion and other mechanical damage to turbine components. 2. Loss of efficiency: Wet steam can lead to a loss of efficiency in the turbine. 3. Permanent warping: Water contact can cause permanent warping or distortion of the turbine, including the diaphragm, rotors, shell, or casing. 4. Corrosion: Carbon dioxide and other acidic species in the condensate can accelerate damage. Water can enter the turbine through a number of connections, including from external equipment or from condensed steam. To prevent water damage, the American Society of Mechanical Engineers (ASME) issued the TDP-1 standard in 1972. The standard covers design, operation, inspection, testing, and maintenance to prevent water induction. The TDP-1 standard recommends: 1. Identifying systems that could allow water to enter the turbine. 2. Detecting the presence of water before it causes damage. 3. Isolating the water after it has been detected. 4. Disposing of the water after it has been detected. 5. It is here that the steam/water level is monitored. If the level is too high it can generate wet steam, which may in turn lead to turbine blade erosion. If the level is too low, the boiler tubes can overheat, with the very real danger of a plant explosion.

Mechanical insulation addresses thermal, acoustical, and safety needs for hot and cold mechanical piping and equipment, utilizing various types tailored to specific requirements, including materials like calcium silicate and traditional fibrous insulation. #mechanicalsystems #mechanicalinsulation #commercialinsulation #insulationinstallers #insulationinstallation

Corrosion has been traditionally avoided by designing heat exchangers with exhaust temperatures well above the Acid Dew Point or ADP. Glass lined shell and tube heat exchangers with glass lined tube bundles could be a game-changer in what's called 'deep waste heat recovery' systems where flue gas temperature could fall below 450F. At or below ADP, recovering the heat with heat exchangers made of conventional high-priced alloys is not economically feasible. However, glass-lined steel tubes and shell provide an economically viable solution for exhaust gas below 250F (NG) or 300F (coal or fuel oils) without risk of Low Temp Corrosion (LTC). The overall thermal efficiency of the system is vastly improved, with a 1% increase in thermal efficiency with every 20C drop in exhaust gas temperatures, a 4-12% increase in thermal efficiency can be achieved. #netzero #sustainability #wasteheatrecovery #aciddewpoint #lowtemperaturecorrosion https://lnkd.in/eDZbPJfW

REBUILDING BACK BETTER Some while back I was talking to Thomas Arakal of Hydro Middle East LLC about reverse engineering and he made it quite clear that Hydro did not reverse engineer pumps or pump components, they re-engineered pumps and pump components. It took me a while to understand that because at Coleherne Ltd we usually replace white metal bearings with ‘like-for-like’ Usually it is only after a series of catastrophic failures does the OEM / End-User request re-engineering of a bearing assembly. However, this recent excellent article in “World Pumps” by Ralph Fergusson of Hydro, Inc. in Scotford gives a really good explanation on re-engineering in the context of maintaining older pumps. See pages 34+35: https://lnkd.in/gSarQBXF Just be aware that there is a glitch on sizes and tolerances in some of the text in the online version, so here it is: REBUILDING BACK BETTER – CORRECTED TEXT The last area identified in the root cause analysis of the (BB2-Style) pump system was excessive tolerances of the OEM-supplied parts. These excessive original tolerances resulted in non-concentricity of the rotating and stationary components. Critical fits in the casing and end covers were found to be 0.020” out of round; best practices hold this tolerance to ≤0.002”. Fit tolerances, which best practices hold to 0.002 – 0.004”, were found to be 0.006 – 0.040”. Without concentric components, close clearance mating surfaces will contact and prematurely wear. Excessive wear will result in reduced operating life, increased vibration, reduced efficiency, and more costly repairs. What Ralph has to say in this paragraph on “Rebuilding Back Better” about casing and end-covers is spot-on. There is a direct read across on fits and tolerances on seals to white metal bearings. If you are having repeat failures in your white metal bearings then try asking Coleherne Ltd about improving the life of your white metal bearings. #pumps, #engineering, #maintenance, #sustainability

The Expansion Joint is a vital component in piping systems, allowing for movement and stress reduction. It accommodates misalignments, thermal expansions, and vibrations, ensuring system durability and reliability. Key Features: - Flexibility: Enables axial, lateral, and angular movements. - Vibration Absorption: Reduces noise and dampens vibrations. - Thermal Expansion: Handles thermal changes in pipes. - Misalignment Tolerance: Adjusts for minor misalignments. Types: - Rubber Expansion Joints: Ideal for moderate pressures and vibration absorption. - Metal Bellows: Suitable for high-pressure, high-temperature applications. - Elastomeric Couplings: Excellent for vibration and shock absorption. - Fabric Expansion Joints: Used in ducting systems for air and gas. Applications: - Pipelines - HVAC Systems - Industrial Processes - Water Treatment Plants - Power Plants Advantages: - Movement Absorption - Vibration and Noise Reduction - Ease of Installation - Thermal Expansion Accommodation Disadvantages: - Pressure Limitations - Maintenance Needs - Cost considerations Installation and Maintenance Tips: - Proper Alignment - Torque Specifications - Regular Inspections - Environmental Suitability - Scheduled Replacement The Expansion Joint plays a crucial role in enhancing system longevity and efficiency. Their correct use and maintenance are key to ensuring optimal performance. #Piping #Engineering #Mechanical #PipeLine #Flanges #Joint

Insulation on piping and process equipment is a deceptively complicated subject. Both the reasons to install insulation and the design basis behind it can vary widely. Insulation can be installed for: ➡ Heat or Cold Conservation. You just spent a significant amount of money to cool or heat your fluid and you want it to stay that way. ➡ Touch prevention. OSHA standards require that surfaces at 140°F and above need protection to prevent accidental burns. This type of insulation often only exists in people-accessible areas. ➡ Process Stability. Seasonal or weather-related temperature swings can cause process problems, some of which insulation can mitigate. ➡ External Condensation or Ice Prevention. Cold piping can cause condensation to form on the jacket or, in the case of cryogenic piping, ice. Neither of these things do you want falling on your head out of a pipe rack. ➡ Freeze Prevention. Insulation can extend the time required for a system to freeze in the winter. When combined with heat tracing, insulation can prevent freezing altogether. To accomplish these insulation goals, a variety of design bases can be selected individually or in combination: ➡ Surface Temperature limit. The surface temperature limit may be relative to burns on a person or the dew point of the surrounding air. ➡ Heat Transfer Limit. Whether for process stability or energy conservation requirements, perhaps you just need to make sure the thermal energy you have in the pipe stays relatively constant. ➡ Economics. This consideration is a combination of a heat transfer limit but combined with the effective cost of the insulation. Is it worth to put thicker insulation on the system if the cost of the additional energy saved is not worth the cost of the insulation? Probably not. #pipingengineering #insulation #mechanicalengineering

Thermal Behaviours of Metallic Pipes All material has inherent thermal properties that affect its characteristics depending on the amount of heat or cold it’s exposed to. The more heat is applied, the more materials tend to expand and soften. The colder the conditions, the more materials tend to contract and harden. In the case of metallic piping systems, we are most concerned with linear expansion and contraction. If unaccounted for during the piping system design, length fluctuation can lead to costly issues and failures.  This is especially true for industrial plant systems, which often subject pipe to extreme temperatures and pressures. For example, if a pipeline is constrained at both ends, as it heats up linear expansion will cause compressive stress on the material. When this undue force exceeds the allowable stress on the material, it will result in damage to the pipe and potentially fittings, and valves. Also, sometimes this can even cause leakage from the flanges. Depending on the damage or failure, plants may be forced to conduct frequent repairs, shut-down processes, even caused accidents especially hazardous process. 🌡 How to Determine Thermal Expansion or Contraction To determine how much a pipe will expand or contract, consider these three variables: 1- Coefficient of thermal expansion: Every material has a coefficient of linear thermal expansion. It shows how every degree of temperature change results in a certain amount of linear expansion. 2- Length of pipe: The longer the pipe, the more it will expand or contract. 3- Temperature change: This is the difference between the maximum and minimum temperature the pipe will be exposed to, from the time of installation through its service life.  To determine your pipe’s temperature change, should consider the temperature of the internal fluid as well as the external temperature the pipe is exposed to. #oil #refinery #LPG #LNG #piping #pipeline #expension #thermal #temperature #heat #pressure #thermalexpansion #safety #safedesing #desing #engineer #mechanical #failure #pipe

Guidelines for Designing Heat Exchangers - Heat exchangers may be designed well and or poorly and many in fouling service are designed poorly. We will discuss fouling, monitoring and troubleshooting. https://lnkd.in/gwDvwkS7