ISO 9001-2015


Atlas Copco products

The largest manufacturer of Blowers

Vacuum pumps & Compressors

  • No. 26 - Fath St. 21 - Fath highway - Tehran - Iran
  • 021-66801373

ISO 9001-2015


Atlas Copco products

The largest manufacturer of Blowers

Vacuum pumps & Compressors

Liquid Ring Compressor Engineered Package

Liquid Ring Compressor Engineered Package

The engineered or customized liquid ring compressor packages are designed and manufactured based on requirements of different industries such as oil, gas and petrochemical and they comply with API 681 standard. These packages are fully customized based on customer requirements in each project and all equipment are designed and fabricated upon customer approval.
The service liquid for these packages can be water, oil, hydrocarbons or any other process liquid provided it has the required properties to create a stable liquid ring.
The engineered packages consist of different components which are described briefly here.

General Information


• In compliance with the requirements and specifications of the project however stringent

• In compliance with the standards used in oil, gas and petrochemical industries (API, ASME, …)

• Providing engineering documentation based on VPIS (Vendor Print Index Schedule) including drawings, calculation books, fabrication and inspection procedures, weld books (WPS, PQR, WQT), PFD, P&ID and VDB (Vendor Data Book).

• Conducting inspections and tests during manufacturing and at final stage before delivery based on approved ITP (Inspection and Test Plan). These tests include material certification, dynamic balancing of rotating parts, hydrostatic testing, NDT tests such as PT, RT or MT, performance and mechanical running tests, vibration and noise tests, …

• Project control based on WBS (Work Breakdown Structure) and project time schedule and submitting progress reports (monthly or bi-weekly) to the client


• The engineered liquid ring compressor packages are used in all industries. Below, you can find a list of some example applications.

• Compression and conveyance of wet process gases in oil, gas and petrochemical industries

• Neutral gas conveyance such as Nitrogen

• CO2 gas booster and compressor

• Flare gas recovery system and hydrocarbons recovery

Performance range

• Capacity from 500 to 20000 m3/hr

• Over pressure up to 5 bar g (using 2 compressors in series)

• Power consumption from 15 to 750 kW


Component Description Relevant Standard
Liquid ring compressor – PVI Series The PVI liquid ring compressor either in manufacturer’s standard or API 681 standard is at the heart of the package. Based on customer requirements, different material is chosen based on ASTM standard. The sealing system is either in single or double cartridge design with different flushing systems based on API 682 standard. API 681 for liquid ring compressor

ASTM for material

API 682 for sealing system

Electric motor The driver for each compressor is an electric motor based on project specifications. The motors can be ATEX certified, having different options such as anti-condensation heaters, winding PTC resistors, bearing vibration and temperature sensors. IEC



Power transmission Power transmission can be direct via coupling, gearbox with coupling or v-belt system. API 677 for gear boxes

API 671 for couplings

Separation vessel The separation vessel is used to separate service liquid from entrained gas/vapors. Based on process conditions, the vessel can be of 2-phase (liquid/gas) or 3-phase (water/hydrocarbon/gas) design. ASME Sec. VIII div. 1
Service liquid cooler In total-recirculation systems the service liquid has to get cooled down. This is done using liquid coolers which can be of shell & tube, plate or double pipe design. API 660 and 661

TEMA Class R, C

ASME Sec. VIII div. 1

Valves and piping The material of piping is based on project piping classes and ASTM standard. Different API standards are used for valve design and selection. Different API standards for valves such as API 520 for safety valves or API 6D for ball valves
Liquid circulation pump For high viscous liquids, a circulation pump is required to provide enough head for the liquid through the system. API 610
Condition monitoring system If specified by customer, the compressor can be equipped with condition monitoring system including bearing vibration and temperature sensors. API670
Instruments The instruments used in each package are based on client requirements and approved P&ID. The usual instruments used are pressure and temperature transmitters for inlet/outlet and service liquid line, level instruments for vessel, flow instruments for service liquid line and pressure/temperature gauges. ATEX

Hart protocol with 4-20 mA output for transmitters

SIL for instruments used in emergency shutdown system integration

Pressure and flow control system If specified by customers, the package can be equipped with pressure/flow control components which can be any of the following:

• Variable speed drives for varying motor speed

• Using by-pass line including a pressure transmitter and control valve


Pars Vacuum Industries General Catalogue

Pars Vacuum Industries Liquid Ring Compressors Catalogue