Reciprocating compressor

Design, Construction and Service

Image of Scheme.

Reciprocating compressor preview.

CST: RANGE OF ACTIVITIES

  • Feasibility Studies
  • Machinery Conceptual Design
  • Design of brand-new Machines
  • Design of complete Compressor Lines
  • Optimization and Modernization of Compressor lines
  • Manufacturing of Crankcases and Cylinders
  • Support to Production and Testing of new Machines

CST: FIELD OF EXPERTISE

  • Feasibility Studies
  • Machinery Conceptual Design
  • Design of brand-new Machines
  • Design of complete Compressor Lines
  • Optimization and Modernization of Compressor lines
  • Manufacturing of Crankcases and Cylinders
  • Support to Production and Testing of new Machines

CST’s team of highly experienced design engineers can develop the complete process from the conceptual phase to the detail design through the most advanced and integrated computing tools such as Virtual Prototyping, Computational Fluid-Dynamics (CFD) and Multiphysics.

reciprocating compressor design
reciprocating compressor design
compressor package engineering
compressor package engineering

engineered Products
engineered Products
CONSULTATIVE SERVICE ENGINEERING
CONSULTATIVE SERVICE ENGINEERING

VIRTUAL PROTOTYPING

Virtual Prototyping is a software-based engineering discipline which involves modelling a system, simulating and visualizing its behavior in real-world operating conditions, and tuning its design through an iterative process. The process begins with creating 3D models, combining the geometries of parts and related assemblies with their load conditions. Models are defined by a  commercial and a proprietary software for the simulation of kinematic and thermo-fluid dynamic behavior. It ends with a functional, structural and fatigue testing using linear and multiaxial nonlinear algorithms, depending on the specific part to be analyzed.

VIRTUAL PROTOTYPING CST.

The ability to simulate multiple design interactions in a short amount of time results in a reduced prototyping cost. The time saved can be spent on other tasks related to product development like reliability, maintainability, and design for manufacturing, minimizing the time to market.

VIRTUAL PROTOTYPING INVOLVES:

  • Computer-aided design (CAD)
  • Computer-aided engineering (CAE)
  • Performance Software CST “Reciperf”
  • Finite Element Analysis (stress, temperature distribution, flow etc.)
  • Linear or Multi-Axial Fatigue
  • Added modules that perform various other tasks, such as prototype manufacturing, product life cycle management, etc.
VIRTUAL PROTOTYPING CST.

VIRTUAL PROTOTYPING ALLOWS TO SIMULATE COMPLETE MACHINES AND TO APPLY LOADS AS IN A REAL PHYSICAL OBJECT. KEY DESIGN BENEFITS:

  • Multiple tests possibility during the development of the project, thus real optimization of the design
  • Accurate evaluation of the contribution of various loads than what can be achieved on a real physical prototype
  • “See” things that could not be seen on a real prototype (virtual prototype is a full body model “instrumented” at all points)
  • Significant cost and time savings
  • Avoid (or drastically reduce) the need for a physical prototype

FATIGUE ANALYSIS

Stress analysis is not sufficient in the design of reciprocating machines, such as compressors, pumps, and engines. In fact, the criticality of these machines comes mainly from the large fluctuation of the loads which makes them subject to fatigue. Therefore, it is mandatory to take care of the stress fluctuation induced by the load variation and determine the fatigue safety factor by means of the appropriate method. Depending on the type of load variation, material and elastic or elastic-plastic situation, CST utilizes many different fatigue criteria including:

COMPRESSOR CYLINDER FUID-DYNAMIC ANALYSIS

For some compressor components, such as the cylinders, in addition to the mechanical/fatigue design is necessary also a fluid dynamics check to enable the best energy management. CST has developed a dedicated software for cylinder fluid-dynamic optimization (CylOpt) that helps to define the best shape of the gas passages before undergoing a 3D Computational Fluid Dynamics (CFD) analysis.Thanks to all these professional design tools, CST has successfully developed the complete design of several new machines, from the conceptual phase to the manufacturing specifications.

COMPRESSOR CYLINDER FUID-DYNAMIC ANALYSIS.

FLUID STRUCTURE INTERACTION

In some special cases, when it is necessary to investigate at deep the interaction between a fluid and a mobile mechanical component or when in presence of a two-phase fluid, CST special Fluid Structure Interaction software faces the duty of making the investigation.
The video aside shows the FSI done by CST to study a special case of movement of the valve rings during the opening time.


MODERNIZATION & UPGRADES

CST machine design know-how applies also for improvement of existing reciprocating compressors, by eliminating recurrent problems, helping users to increase the reliability of their plants, reducing operating costs.

CST SERVICE CAPABILITIES. CLICK ON THE IMAGES TO KNOW MORE

For some compressor components, such as the cylinders, in addition to the mechanical/fatigue design is necessary also a fluid dynamics check to enable the best energy management. CST has developed a dedicated software for cylinder fluid-dynamic optimization (CylOpt) that helps to define the best shape of the gas passages before undergoing a 3D Computational Fluid Dynamics (CFD) analysis.Thanks to all these professional design tools, CST has successfully developed the complete design of several new machines, from the conceptual phase to the manufacturing specifications.

CST Machine Design capability for Reciprocating Compressors, typical applications:

  • Compressor Frame design including Crank-mechanism, crankcase and all their components
  • Compressor Cylinder design for all main application (Process, Low temperature, High pressure LDPE, CNG, Hydrogen, etc)
VIRTUAL PROTOTYPING CST.
VIRTUAL PROTOTYPING
Machine design is done by CST engineers through virtual prototyping technique which allows to take into account all forces and constraints as in a physical prototype to reproduce the actual operating conditions
FLUID-DYNAMIC CYLINDER DESIGN–VALVE POCKETS.
FLUID-DYNAMIC CYLINDER DESIGN–VALVE POCKETS
One of the most critical gas passages in the reciprocating compressors is the "valve pocket". CST designs those passages by the proprietary software Cylopt-Mono, followed in the most challenging cases by a CFD analysis
COMPLETE GAS PASSAGE CFD ANALYSIS.
COMPLETE GAS PASSAGE CFD ANALYSIS
A case of a full CFD analysis done by CST for the design of the gas passages of the whole cvlinder. This study was done to fine-tune the first selection done with the proprietary software Cylopt-Mono.
PRESSURE DISTRIBUTION ON LARGE BORE CYLINDERS.
PRESSURE DISTRIBUTION ON LARGE BORE CYLINDERS
Large bore cylinders face uneven pressure distribution on the piston faces when they are close to the dead centers. CST analyses these cases by a software of Fluid-Structure-Interaction.
MAIN THREADED CONNECTIONS.
MAIN THREADED CONNECTIONS
Main threaded connections need a detailed analysis to assess the infinite fatigue life of the relevant components. For the connection of the piston rod to the crosshead CST simulates the real threads going beyond the normal solid representation of the connection.
COMPRESSOR BALANCING
COMPRESSOR BALANCING
Balancing reciprocating masses is of the utmost importance to reduce compressor vibration. CST gives particular care to the design of ballasts, counterweights, opposed cylinder line offset and foundation bolts.
DESIGN FOR VIBRATION FREE OPERATION
DESIGN FOR VIBRATION FREE OPERATION
To avoid dangerous vibrations the bare compressor shall generate the minimum of excitations and to constitute a stiff connection for the piping system. CST, thanks to its multi-disciplinarity, can take care of all these aspects.
CRANKSHAFT DESIGN.
CRANKSHAFT DESIGN
The crankshaft is designed through a linear elastic FEM analysis and fatigue evaluation by Dang Van fatigue criterion.
CONNECTING ROD REVAMPING.
CONNECTING ROD REVAMPING
CST was requested by a customer to revamp an old reciprocating compressor. The connecting rod was reviewed to debottleneck the weak points.
CONNECTING ROD BOLTS DESIGN.
CONNECTING ROD BOLTS DESIGN
The connecting rod tie bolts are designed by CST through a linear elastic FEM analysis with fatigue evaluation by the multi-axial non proportional Brown Miller criterion.
CRYOGENIC CYLINDERS.
CRYOGENIC CYLINDERS
A typical double-acting cryogenic cylinder designed and manufactured by CST utilizing special materials suitable for very low temperature.
TIGHTENING SYSTEMS.
TIGHTENING SYSTEMS
The best insurance for a good operation of the bolting subject to fluctuating loads is a correct preload and an adequate elasticity of the connection. CST designs the connections and supplies the tightening system to avoid uncertainties of the preload.

RECONDITIONING AND UPGRADE OF EXISTING COMPRESSORS

CST service is not limited to the design and manufacturing of new units but covers also its customer for repairs instructions, parts reverse engineering and provision, modification, and optimization of existing compressors to meet new plant requirements, different gas condition and improve compressor performance.

Learn More

LEARN MORE ABOUT CST RECIPROCATING COMPRESSORS

compressor package engineering
compressor package engineering

engineered Products

CONSULTATIVE SERVICE ENGINEERING CST.
CONSULTATIVE SERVICE ENGINEERING

For information on CST activities, email to:

FILIPPO CINELLI at filippo.cinelli@cstfirenze.com

LUCIA MATTESINI at lucia.mattesini@cstfirenze.com

GIULIA TOSI at giulia.tosi@cstfirenze.com

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