Description

COMPRESSOR

The Vilter Single Screw Compressor is a positive displacement, capacity and volume controlled, oil flooded, rotary compressor which uses a single main screw intermeshed by two opposing gate rotors. Gas compression occurs when the individual fingers of each gate rotor sweep through the grooves, or flutes, of the main screw as the screw rotates. Compression occurs from the time the screw flute is first closed off by the gate rotor finger, until the time when the screw flute has rotated to the point of lining up with the discharge port in the compres- sor housing. A labyrinth type seal is used to prevent gas at discharge pressure from leaking past the end of the screw. Any discharge gas leakage past the labyrinth seal is vented back to suction via four longitudinal holes drilled through the body of the screw.

By venting the discharge end of the main screw back to suction, forces on each end of the screw are equal. This results in zero net axial forces on the main bearings. With twin opposing gate rotors, all radial forces are can- celled out also. Main shaft bearings have no net forces except the weight of the screw and the shaft assembly.

The compressors are comprised of three rotating assemblies: the main screw assembly and the two gate ro- tor assemblies. Each of these rotating assemblies use a common bearing configuration consisting of a single, cylindrical rolling element bearing at one end, and a pair of angular contact ball bearings at the other end. The pair of angular contact ball bearings are used to axially fix one end of the rotating shafts, and to absorb the small amount of thrust loads on the shafts. The inner races of the ball bearings are securely clamped to the rotating shafts, while the outer races are securely held in the bearing housing, thus fixing the axial position of the shaft in relation to the bearing housings. The cylindrical roller bearings at the opposite end of the shafts allow for axial growth of the shafts while supporting the radial loads from the shafts.

The suction gas enters the compressor housing through the top inlet flange, at the driven end of the unit. The driven end of the compressor housing is flooded with gas at suction pressure. The gas enters the open end of the main screw flutes at the driven end, and becomes trapped in the screw flute as the screw rotates and the gate rotor tooth enters the end of the flute. At this point, the compression process begins. Directly after the screw flute is closed off by the gate rotor tooth, oil is injected into the groove.

The oil enters the compressor through a connection at the top of the compressor. The purpose of the injected oil is to absorb the heat of compression, to seal the gate rotor tooth in the groove, and to lubricate the moving parts.

Additional internal oiling ports are provided at the main and gate rotor bearings to cool and lubricate the bear- ings. The mechanical shaft seal housing also contains oiling ports to lubricate, cool and provide a sealing film of oil for the mechanical shafts seal. Excess oil flows through the check valves on the sealing baffle plate. This oil is directed at the main rotor roller bearing, which cools and lubricates the front roller bearing.

As the main screw rotates, the gate rotor is also driven, causing the gate rotor tooth to sweep the groove in the main screw. This sweeping action reduces the volume of the groove ahead of the gate rotor tooth and causes the trapped gas and oil to be compressed in the reduced volume. As the main screw continues to rotate, the gate rotor tooth continues to reduce the groove volume to a minimum, thus compressing the trapped gas to a maximum pressure. A labyrinth seal arrangement prevents the compressed gas from leaking past the end of the screw. As the gate rotor tooth reaches the end of the groove, the groove rotates to a position that lines up with the discharge port in the compressor housing and the gas/oil mixture is discharged from the screw at high pressure. This completes the compression cycle for a single flute of the main screw.

Once the gas is swept from the main screw flute through the discharge port, it passes into the discharge manifold of the compressor. From the discharge manifold, the gas/oil exits the compressor housing

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Emerson VSM, VSR, VSS service manual Description, Compressor
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VSS, VSM, VSR specifications

Emerson VSM, VSR, and VSS are advanced technologies designed for process automation and control, often utilized in industrial applications. These systems are part of Emerson's broader portfolio of solutions aimed at enhancing operational efficiency, safety, and reliability.

The Emerson VSM, or Valve Signature Management, focuses on the digital management of valves within a system. One of its main features includes advanced diagnostics that monitor the health and performance of control valves. This technology allows for predictive maintenance, ensuring that valves operate at peak efficiency and reducing the risk of unexpected failures. The VSM utilizes a combination of smart sensors and actuators to gather data, enabling real-time analytics that can enhance decision-making and operational strategies.

On the other hand, VSR, or Valve Status Reporting, enhances visibility into the operational state of valves in real time. This system provides operators with critical updates and alerts related to valve conditions, significantly reducing response times to potential issues. The VSR technology integrates seamlessly with existing control systems, allowing for easier implementation and minimal disruption to ongoing operations. The reporting capabilities feature user-friendly dashboards that present complex data in a straightforward manner, empowering operators to make informed decisions quickly.

The Emerson VSS, or Valve Service Solutions, complements the VSM and VSR by focusing on the maintenance and support of valve systems. This offering includes comprehensive service packages that range from routine maintenance to advanced troubleshooting and repair. The VSS is designed to improve the lifespan of valves through proactive service, ensuring reliability and minimal downtime. Emerson’s trained technicians leverage predictive analytics derived from VSM and VSR data, allowing for timely intervention before issues escalate.

In summary, Emerson’s VSM, VSR, and VSS technologies work together to create a robust ecosystem for valve management in industrial settings. The combination of advanced diagnostics, real-time reporting, and comprehensive service solutions provides operators with a powerful toolkit aimed at optimizing performance and ensuring operational reliability. With these technologies, companies can embrace digital transformation, reduce operational risks, and improve overall process efficiency, leading to a safer and more productive environment. Each component plays a crucial role in empowering industries to meet the challenges of modern automation and maintain competitive advantages in their respective markets.
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