Tumansky R-25
The Tumanski R- 25 is a twin- jet engine, which was manufactured in the USSR in large series.
History
The R- 25 was developed in the late 1960s until 1971 by Sergei Alekseevich Gavrilov from the Tumanski R-13 and is also a two-shaft turbojet. For this purpose, the engine was equipped with a new three-stage low-pressure compressor with 21 titanium blades wide and a revised afterburner with two fuel pumps and improved cooling. It was used in the MiG -21bis and the Su- 15bis; a total of about 3200 units were produced.
Versions
- R -25 -300 / R- 25F -300 - version of the MiG -21bis and the Su- 15 to
- R -25 -300 94 - version for the MiG - 21-93
Construction
Stator
The stator consists of seven steps. In the first stage of stator vanes comprises a total of 36. Five of these blades being designed as a hollow blades. One of which has an axial bore through which the axial shaft is guided for the drive of the front bearing Schmierstoffabsaugpumpe. The other four are hollow blades
The Hochdruckstator serves to hold the 4th, 5th, 6th and 7th level, the diffuser, it is divided into two parts for assembly reasons and joined together with bolts. The casing of the first compressor stage and the 1st to the 7th stage guide vanes are made of titanium, the body of the steps 2 to 7 are made of steel.
Low pressure rotor
The low-pressure rotor is comprised of the inseparable discs of the second and third compressor stage and the removable disk of the first compressor stage. It is mounted on two bearings.
High pressure rotor
The high pressure rotor is comprised of five disks that are made of a titanium alloy.
Two-stage turbine
The first turbine stage 55 has the blades and is supported on two bearings. It is made from forged pieces made of a heat -resistant alloy. The blades, which sit on the disc, are hollow for cooling and precision molded from a heat-resistant alloy. The second stage turbine has 64 blades, which also sit on a guided by two bearing washers and secured with a tooth tree with five teeth. The turbine is air which is taken from different points of the air path of the engine is cooled.
Accessory drive
The aggregates of the engine to be driven from either the shaft of the low pressure or the high pressure rotor. At the low pressure rotor, the Schmierstoffabsaugpumpe the front bearing and the speed sensor of the low pressure rotor is flanged over a couple of spur gears. The aggregates, which are connected to the shaft of the high pressure rotor are listed in the table.