Improving compressor and expander efficiency
Operating two pinions through one common bull gear, integrally geared design provides multi-speed capability for your turbocompressor and turboexpander. This allows you to run each machine stage at its optimum speed, ultimately giving you best efficiency possible. Generally, it is economically desirable to use the smallest possible compressor. The higher the flow coefficient, the larger the suction rate for any given impeller diameter. For a multi-stage compressor, the first stage impeller is designated to have the maximum flow coefficient. The flow coefficient of the subsequent impellers decreases as inlet volume decreases, if the shaft speed is constant (e.g. single shaft technology). Increasingly, that leads to sub-optimal designs as the suction volume of the subsequent compressor stages decreases.
Optimal efficiency and cost
With integral gear technology, the speeds of the subsequent impellers along the compression are adopted in order to achieve the best possible design in terms of your equipment efficiency and cost. As a matter of fact, integral gear technology is extremely well suited to customize compressors to your specific process conditions and requirements – especially for higher pressure ratios.
The roots of integral gear technology
Our track record includes hundreds of integrally-geared units built according to API 617, chapter 1 and chapter 3. Integrally geared equipment was introduced almost 70 years ago in the air separation industry. Subsequently, it emerged as a proven technology, benefiting from advancements in aerodynamic, rotor-dynamic and thermodynamic knowledge, and from advanced methods to producing accurate rotating and various complex components – all this at reasonable costs. Improvements to shaft seal technology further drove the move, with integrally geared compressors being fully accepted by refinery and petrochemical markets after its inclusion into 7th edition of API 617 in chapter 3 in 2002. With decreasing complexity, higher reliability and lower weight through compact design, that’s even more so the case today.