Storage tank, abbreviated as TK, is used to store volumes of fluids for storage or as part of a process.
Nomenclature & Symbols for
Nomenclature & Symbols
Storage Tank Types
Vertical tank (bolted and welded) (double wall and single wall)
- Open top tank (atmospheric) - Normally for petroleum products but can contain cooling water and fire water.
- Fixed roof tank (atmospheric, low pressure, high pressure) - Either be self supported or rafter/trusses supported depending on size.
- Cone roof tank (supported and self supported)
- Dome roof tank (supported and self supported)
- Internal floating roof tank (supported and self supported)
- Floating roof tank - Roof sits directly on top of product.
- External floating roof tank - Roof sits directly on top of product, open to atmosphere.
- Internal floating roof tank - Roof sits directly on top of product, tank has a fixed roof.
Horizontal tank (double wall and single wall)
- Bullet tank - Presurized liquid gas tank.
Spherical tank - Presurized liquid gas tank.
Storage Tank Standards
- API Std 620 - Standard for Design and Construction of Large, welded, Low-pressure Storage Tanks
- API Std 650 - Standard for Welded Steel Tanks for Oil Storage
- API RP 651 - Recommended Practice for Cathodic Protection of Aboveground Storage Tanks
- API RP 652 - Recommended Practice for Cathodic Protection of Aboveground Storage Tanks
- API Std 653 - Standard for Tank Inspection, Repair, Alteration, and Reconstruction
- API Std 2000 - Standard for Venting Atmospheric and Low-pressure Storage Tanks: Nonrefrigerated and Refrigerated
- API Std 2015 - Standard for Requirements for Safe Entry and Cleaning of Petroleum Storage Tanks
- NACE RP0193 - External Cathodic Protection of On-grade Metallic Storage Tank Bottoms
- NACE SP0102 - In-Line Inspection of Pipelines
- NACE SP0106 - Control of Internal Corrosion in Steel Pipelines and Piping Systems
- NACE SP0169 - Control of External Corrosion on Underground or Submerged Metallic Piping Systems
- NACE SP0188 - Discontinuity (Holiday) Testing of Protective Coating
- NACE SP0193 - External Cathodic Protection of On-Grade Carbon Steel Storage Tank Bottoms
- NACE SP0216 - Steel-Cased Pipeline Practices
- NACE SP0205 - External Corrosion Control of Underground Storage Tank Systems by Cathodic Protection
- NACE SP0285 - Corrosion Control of Underground Storage Tank Systems by Cathodic Protection
- NACE SP0502 - Pipeline External Corrosion Direct Assessment Methodology
- NACE SP0607 - Petroleum and Natural Gas Industries Cathodic Protection of Pipeline
- NACE Publication 51317 - Performance Failure of API 650 Oil Storage Tank Bottom Plates Due to Soil Side Corrosion
- NACE Publication 51318-11258 - Robotic Online Storage Tank Floor Inspection Case Study
- NACE Publication 51318 - Linings of Aboveground Storage Tanks
- NACE Publication 1E100 - Engineering Symbols Related to Cathodic Protection
- NACE TR21447 - Consequences of Coating Failures as Related to Interaction with Cathodic Protection
Storage Tank Glossry
- A - B - C - D - E - F - G - H - I - J - K - L - M - N - O - P - Q - R - S - T - U - V - W - X - Y - Z
- Absolute pressure - A pressure at absolute zero can only exist in a total vacuum and any pressure above this is called absolute pressure.
- Acid gas (sour gas) - Any significant amount of hydrogen sulfide (H2S) and carbon dioxide (CO2) contains a natural gas that can cause corrosion.
- Anchor bolt -
- Anode -
- Atmospheric pressure - The pressure exerted upon the earth's surface by the air because of the gravitational attraction of the earth.
- Baffle - Reduces disturbance and surges from the inlet fluids in horizontal or vertical. The most used type is a perforated plate in the shape of a segmented circle.
- Base plate - A plate attached to the bottom of the support that sits on the foundation.
- Barlow's formula - The point just before or at when a pipe or tubing fails under pressure.
- Blind flange - A piping component for covering or closing the end of a pipe, valve, vessel or tank.
- Catalyst - A material that aids or promotes a chemical reaction between other substances but does not react itself.
- Cavitation - The creation and collapse of bubbles in a liquid.
- Corrosion - The thinning of a pipe wall that is typically caused by a chemical reaction from a corroding fluid or agent and is limited almost exclusively to metal products.
- Corrosion allowance - The amount of material in a pipe or vessel that is available for corrosion without affecting the pressure containing integrity.
- Corrosion inhibitor - A substance that slows down the chemical reaction rate of corrosion on metal that is exposed to the environment.
- Crude - A mixture of naturally occuring liquid hydrocarbons before refining.
- Crude oil - See crude.
- Data plate - On all vessels. Gives the manufacturer, year manufactured, pressure, temperature, and any other indormation needed about the vessel.
- Davit arm -
- Design pressure - The pressure the vessel is designed for.
- Design temperature - The temperature the vessel is designed for.
- Distillate - Products of distillation formed by condensing vapors.
- Enthalpy - Measures the sum of internal energy changes in heat under constant pressure of the system.
- Flange - A bolted connection where two pieces of pipe, equipment, fittings or valves are connected together to form a piping system.
- Flush-type cleanout -
- Gate valve - One of the most frequently used valve in piping systems and is classified as either "rising-stem" or "nonrising-stem" valves.
- Gas boot vapor -
- Gauge hatch -
- Globe valve - A type of valve used for regulating fluid flow, both on/off and throttling, it is a control valve.
- Grounding lug -
- Gusset plate - A thick steel plate used to strengthen joints on new and retrofitted structures.
- Head - The end closure of the vessel.
- Heat - A form of energy that causes physical change in what is being heated.
- Heat transfer - The exertion of power that is created by heat, or the increase in temperature.
- Heavy crude - Crude oil with a high proportion of heavy hydrocarbons and metallic content.
- Holiday - A discontinuity in painted or coated surfaces.
- Inlet with spreaded -
- Jacket vessel - An external cavity around the vessel, controlling the temperature of the contents of the vessel through a cooling or heating fluid.
- Latent heat - The energy absorbed or released by a substance during a constant temperature or phase change from a solid to liquid, liquid to gas or vise versa.
- Level interface -
- Level switch - Provides a discrete input to the PLC. The level switch is typically used as a method of control in tanks and vessels.
- Light crude - Crude oil with a light proportion of light hydrocarbons fractions and low metallic compounds.
- Liquid - A specific volume and can hold any shape it is contained within.
- Liquefied natural gas - Natural gas cooled to a liquid state.
- Manway - An opening on a tank or vessel designed as an entryway for personal access and equipment.
- Mass flow rate - The average velocity of a mass that passes by a point.
- Maximum operating pressure - The maximum pressure permissible at the top of the vessel during normal operation.
- Maximum operating pressure - The maximum temperature permissible that provides sufficient flexability during normal operation.
- Nameplate - On all vessels. Gives the manufacturer, year manufactured, pressure, temperature, and any other indormation needed about the vessel.
- Nozzle - A nozzle, abbreviated as NOZ, is a An opening in a tank or vessel for a flanged connection.
- Oil outlet -
- Overflow -
- Petroleum - See crude.
- PH - How acidic or alkakine water is.
- Pressure - It is the force exerted perpendicular to the surface of an object and is expressed as force per unit area.
- Pressure differential - The pressure difference between two points of a system.
- Pressure loss - The difference in upstream and downstream pressure.
- Pressure safety valve - Used to protect vessels and tanks from overpressure. It is designed to protect critical system components such as pressure vessels, tanks and flange ratings.
- Programmable logic controller - The types of signals are analog output (AO), analog input (AI), discrete output (DO), and discrete Input (DI).
- Raw water - Untreated water.
- Saddle - Used to support horizontal and vertical designs in locations to support the concentrated loads at on each end of the vessel.
- Sample box - A sample box is a series of pipe, valves and fittings located on a pressure vessel or tank that is used to manually determine the height of the liquid or where the interface between oil and water resides.
- Sand pan -
- Saturated steam - The point (temperature and pressure) when steam is in contact with the liquid water (boiling) it came from.
- Sensible heat - The heat added to a substance which increases its temperature but not the phase is called sensible heat.
- Shell - The cylinder portion of the vessel.
- Shell nozzle -
- Shell platform -
- Slip-on flange - Designed to slip over the outside of pipe, long-tangent elbows, reducers, and swages.
- Sour gas - See acid gas.
- Specific gravity - The density or ratio of any substance to another substance.
- Stack gas - Anything that comes out of a burner stack in gaseous form.
- Stress - The force per unit area of cross-section.
- Stub end - Allows a flange to swivel in order to mate with another flanges bolt holes that may not align perfectly.
- Sweet crude - Crude oil with a sulfur content less than 0.5% by weight, no sulfur smell.
- Tail gas - The lightest hydrocarbon gas released from a refining process.
- Temperature - The amount of heat or cold, but it is neither heat or cold.
- Tension strength - The capacity of a material to resist a force tending to stretch it.
- Thermal expansion - The increase in length, area or volume due to the increase (in some cased decrease) in temperature.
- Thermowell - Used in temperature measurement and provide isolation from the temperature sensor and the process fluid.
- Truck connection -
- Vacuum breaker - A vent on top of the vessel that allows air to be pulled into the tank.
- Vacuum tank - Uses high-pressure hoses to clean out liquids and sludges without any damage to the object being cleaned.
- Vapor recovery -
- Venting roof nozzle -
- Vessel internals - Vessels have internals to help them effectively process the fluids go through it.
- Viscosity - The measure of the internal friction/resistance to the flow of a liquid.
- Vortex breaker - When the flow exits a nozzle it will create a vortex. A cross of plates on the discharge nozzle will prevent the discharge from swirling.
- Water - Can exist in three of the four phases of matter: gas, liquid, or solid.
- Water hammer - A valve is suddenly opened or closed.
- Water outlet -
- Weep - A term applied to a minute leak.
- Welding - The fabrication process that fuses like materials togeather by heating them to a suitable temperatures, this can be acomplished by brazing, soldering or welding.
- Wet gas - A gas containing a relatively high portion of hydrocarbons that are recoverable as liquids.
- Wier box -
- Working pressure - The normal pressure that a system operates at.
- Yield strength - The minimum stress that leads to permanent deformation of the material.