Turbine oils: characteristics, classification and application

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

Turbine oils are widely used for lubrication and cooling of bearings in various turbine generators - steam and gas turbines, hydro turbines, turbopumps. They are also used as a working fluid in turbine control systems and industrial equipment.

What properties does it have?

The turbine is a complex mechanism that must be handled with care. The turbine oils used must meet a range of specifications:

• have antioxidant properties;
• protect parts from deposits;
• have demulsifying properties;
• be resistant to corrosion;
• have low foaming;
• be neutral to metal and non-metal parts.

All these characteristics of turbine oils are achieved during production.

Production Features

Turbine oils are produced from highly refined petroleum distillates to which additives are added. Thanks to antioxidant, anti-corrosion, anti-wear additives, their performance characteristics are improved. Because of all these additives, it is important to choose oils according to the manufacturer's instructions.operation of a particular unit and the recommendations of the manufacturer. If the turbine oil is of poor quality, the unit may simply fail. To achieve high quality in the production of compositions, high-quality grades of oil are used, deep cleaning is used during processing and the introduction of additive compositions. All this combined can improve the antioxidant and anti-corrosion properties of oils.

Basic Requirements

Rules for the technical operation of various pumping stations and networks say that turbine oil should not contain water, visible sludge and mechanical impurities. According to the instructions, it is also required to control the anti-rust properties of the oil - for this, special corrosion indicators are used, located in the oil tank of steam turbines. If, nevertheless, corrosion appears in the oil, it is necessary to introduce a special additive against the appearance of rust into it. We offer an overview of popular brands of turbine oils.

TP-46

This oil is used to lubricate bearings and other mechanisms of various units. Turbine oil 46 shows good antioxidant properties. To create it, sulfuric paraffinic oil of deep selective purification is used. The composition can be used on ship steam power plants and in any auxiliary mechanisms. TP-46 serves as a reliable protection of surfaces of parts from corrosion, is highly stable against oxidation and does not emit precipitation during long-term operation of turbines.

TP-30

Turbine oil 30 is produced on the basis of mineral base oils, where additives are added to improve the performance properties of the composition. Experts advise using TP-30 in turbines of any type, including gas and steam ones. Moreover, the operation of the oil is available even in harsh climatic conditions. Among the distinguishing features of TP-30 are excellent antioxidant capacity, good level of corrosion protection, minimal cavitation, excellent thermal stability.

T-46

Turbine oils T-46 are made from low-sulfur paraffin-free high-quality oils without additives, which ensures the availability of its cost while maintaining all performance characteristics. The quality raw materials used for production allow reaching a certain level of viscosity for the oil, which makes it easier and more convenient to clean. The use of this composition is advisable in marine turbines, steam turbine units.

TP-22S

Turbine oil TP-22S allows lubrication and cooling of bearings, auxiliary mechanisms of steam turbines that operate at high speeds, and it can also be used as a hydraulic fluid and sealing medium in sealing and control systems. Benefits of this oil include:

• excellent performance due to highly refined mineral base and effective additive formulation;
• excellent demulsifying properties;
• excellent stability against oxidation;
• high viscosity;
• minimum cavitation.

This oil is used in turbines for various purposes - from steam and gas to gas turbines of power plants.

TP-22B

Turbine oil TP-22B is produced from paraffinic oils, and cleaning is carried out with selective solvents. Thanks to the additives, a good level of resistance to corrosion and oxidation is achieved. If we compare TP-22B with TP-22S, then the former forms less sediment during equipment operation, it is more durable in use. Its peculiarity is the absence of analogues among domestic grades of turbine oils.

LukOil Tornado T

This series offers a wide range of high quality turbine oils. They are based on base oils produced by a special synthetic technology with the use of high performance ashless additives. Oils are developed in accordance with the latest requirements for compositions of this kind. It is advisable to use them in steam and gas turbines with and without gearboxes. Excellent antioxidant, anti-corrosion and anti-wear properties contribute to minimal deposit formation. The oil is specially adapted for modern high-performance turbine units.

Features of the composition

Modern turbine oils are created on the basis of special paraffin oils with certain viscosity-temperature characteristics, andalso antioxidants and corrosion inhibitors. If the oil is to be used in turbines with gear boxes, they must have a high bearing capacity, and for this, extreme pressure additives are added to the composition.

Base oils are obtained by extraction or hydrogenation, while high pressure refining and hydrotreating achieve turbine oil characteristics such as oxidation stability, water separation, deaeration, which in turn affect pricing.

For different types of turbines

Turbine oils (GOST ISO 6743-5 and ISO/CD 8068) are used for modern gas and steam turbines. The classification of these materials, depending on the general purpose, can be represented as follows:

• For steam turbines (including those with gears under normal load conditions). These lubricants are based on refined mineral oils supplemented with antioxidants and corrosion inhibitors. The use of oils is advisable for industrial and marine drives.
• For steam turbines with high bearing capacity. These turbine oils additionally have extreme pressure characteristics that provide gear lubrication during equipment operation.
• For gas turbines: these oils are made from refined mineral compounds, where antioxidants, corrosion inhibitors are added.

Cleaning features

Internal parts of any mechanism deteriorate over timedue to natural wear and tear. Accordingly, mechanical impurities in the form of water, dust, chips also accumulate in the lubricating oil itself as it is used, and an abrasive will begin to form. To make the operation of the equipment full-fledged and longer, it is possible to constantly monitor and clean the turbine oil to remove mechanical impurities from it.

Note that modern oils make it possible to optimize and increase the efficiency of the production process due to the full protection of parts and components of equipment. High-quality purification of turbine oil is a guarantee of reliable operation of turbine units for a long period without failures and malfunctions of the equipment itself. If low-quality oil is used, the functional reliability of the equipment will be called into question, which means that it will wear out prematurely.

Recovered oil after cleaning can be reused. That is why it is advisable to use continuous cleaning methods, since in this case it is possible to increase the life of the oil without needing to refill it. Turbine oils can be purified by various methods: physical, physico-chemical and chemical. Let's describe all the methods in more detail.

Physical

These methods purify turbine oil without violating its chemical properties. Among the most popular cleaning methods:

• Settling: oil is cleaned from sludge, water, mechanical impurities through special settling tanks. An oil tank can be used as a sump. Flawmethod in low productivity, which is explained by the long stage of delamination.
• Separation: oil is cleaned from water and impurities in a special centrifugal force separator drum.
• Filtration: With this method, the oil is purified from impurities that cannot be dissolved in it. To do this, the oil is passed through a porous filter surface through filter paper, cardboard, felt or burlap.
• Hydrodynamic cleaning: this method allows you to clean not only the oil, but also all equipment. During operation, the oil film between metal and oil remains intact, corrosion does not appear on metal surfaces.

Physico-chemical

When using these cleaning methods, the chemical composition of the oil changes, but only slightly. These methods suggest:

• Adsorption treatment, when the substances contained in the oil are absorbed by solid highly porous materials - adsorbents. In this capacity, aluminum oxide, enamels with a whitening effect, silica gel are used.
• Flushing with condensate: this method is used if the oil contains low molecular weight acids that are soluble in water. After flushing, the performance of the oil improves.

Chemical Methods

Cleaning by chemical methods involves the use of acids, alkalis. Alkaline cleaning is used if the oil is very worn out, and other cleaning methods do not work. Alkali affects the neutralization of organic acids, sulfuric acid residues, the removal of esters and other compounds. cleaningis carried out in a special separator under the influence of hot condensate.

The most effective way to clean turbine oils is to use combined units. They involve cleaning according to a specially designed scheme. In industrial environments, universal installations can be used, thanks to which cleaning can be carried out in a separate method. Whatever cleaning method is used, it is important that the final quality of the oil is at its best. And this will increase the period of stable operation of the equipment itself.