2000 kW 24/2.5 Bar Atlas Dual Back Pressure Turbine

Description

Used 2000 kW Atlas dual back pressure turbine C - 700 TE with gearbox connected via coupling to a Škoda 1994 generator. The generator is coupled to the turbine on a steel frame. Single-stage steam turbine with an integrated gearbox. The turbine stage itself is attached to the gearbox with one high-speed pinion, on which the turbine impeller with two-stage axial blading type C is mounted. The cabinet is mounted on the transmission. Bearing lubrication gear is protected from the generator oil system.

Rated steam parameters*
Input: 2.4 [MPa abs.] 350 [°C]
Output: 0.25 [MPa abs.] 210 [°C]
RPM: 6000/3000 [min⁻¹]

Steam consumption, performance
Steam flow: 30 [t/h]
Rated power: 2000 kW

Generator
Rated voltage: 6300 V, 3 phase
Electrical performance: 2500 [kW]
At the terminals of the electrical generator

Regulation
Turbine operation is ensured by electronic regulator TR 101 and electro-hydraulic oil low-pressure unit Voith.
The regulatory quick-closing valve is controlled by the oil pressure unit.
Turbine regulation allows these types of operation:
- Speed control maintains the desired speed during turbine start-up, before connecting the generator to the electrical grid, and during controlled shutdown after disconnecting the generator.
- Backpressure regulation operates only when the generator sets are running and connected to the electrical grid. Steam flow to the turbine is determined by the immediate demand of steam appliances, and electrical power corresponds to this flow (that is, electrical power produced should be used). Pressure regulators maintain a constant (adjustable) backpressure.
- Oil management for lubrication of bearings and gearwheels of the transmission:
- Main gear-driven oil pump supplies pressurised oil for lubrication of turbine components in operation (gear). Additionally, an electric oil pump is available.
- Emergency oil pump driven by an electric motor supplies pressurised oil for lubrication and cooling of bearings in the event of a complete power failure (powered from an independent source such as UPS).

The oil tank has a volume of about 400 litres. For lubrication, turbine oil TB-46 or equivalent complying with IEC 65 6620 can be used.
Oil cooler (2 x plate L25 GG 60) uses aggressive cooling water. Maximum water flow at 20 °C is about 8.4 +5.2 t/h, cooler pressure loss is about 35 kPa with warming water of 8 °C.
Required cooling water overpressure is 0.6 MPa.
Chemically treated water is recommended for cooling with the following parameters:
- Mechanical particles content max: 50 mg/l
- pH: 7 to 8.3
- Hardness: 4 to 7 mg equiv.
- Content of impurities: 700 to 1000 mg/l
It is recommended to insert a coke filter into the water circuit.
- Two oil filters – each containing 6 x insert CFO 11942, 25 microns.