Compressor 2MCL1006+2MCL456 is used to compress air in the process cycle of ammonia production. A double-effect, four-section compressor. In low and high pressure casings the sections are designed according to 'back-to-back' layout, 3 stages in each. After each section the gas temperature goes down in air cooling units. A steam turbine is the driver. The rotor of the high pressure casing is rotated through a multiplier.
In 2014 in JSC Nevinnomyssky Azot in 1-Б ammonia production shop integrated reconstruction was conducted which was aimed at achieving product output at the level 2,000 tons/day. An objective was set to LLC RPC ENTECHMASH to upgrade the air compressor with an increase in output ~35% above the design one.
A 'load' on sections 1 and 2 was increased (increased pressure ratio in the section) and section 4 was 'unloaded' in order to reduce power consumption and increase surge margin.
The design is fulfilled using a high-flow impeller of stage 1 determining the compressor's output. Axisymmetric radial-axial sections before the entry to the impellers of the sections were reprofiled to reduce stall zones. Diffuser vane airfoils are optimized ensuring a separation-free flow in the vane channel near the optimal operating conditions.
Reverse guides are designed for enhanced consumption. Labyrinth seals with staged grooves to match the labyrinth nibs are used to reduce leakage.
Jointly with the company Alstom Power a drive steam turbine was upgraded to ensure the required enhanced power. A new multiplier Flender is installed.
In December 2014 acceptance tests were performed, the compressor set was commissioned. The necessary output and final pressure were achieved, the power consumption of the compressor corresponds to the demand one.