INCDT - COMOTI

SCREW COMPRESSORS – FROM LICENSE

AGREEMENTS TO NEW SIZES

ROMANIA www.comoti.ro contact@comoti.ro

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1. Overview As part of the displacement compressors group, the screw compressor is the type of compressor that in the last 10 to 15 years had the highest growth in terms of number of compressors supplied on market. Both technological progress and finite element calculation opportunities (using CFD analysis) led to this trend in the market. Screw compressors with oil injection offer several of advantages for the range of applications that require high efficiency and high discharge pressure: • The lubrication system eliminates the need of using synchronizing gears used in dry

screw compressors; • Usually, the male rotor is directly coupled to the driving motor, which leads to a

reduction in manufacturing cost; • Oil injections provides a seal between rotors and the housing, respectively ensure

corrosion protection, noise reduction, gas cooling; • Do not surge; • Robustness and high reliability; • Reduced maintenance; • Exhaust temperature control, avoids the problems caused by dew point; • Tolerance to liquid particles; • Reduced vibrations due to rotational movement (will require a simple foundation).

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All these advantages have required the use of screw compressors in the following applications: • Extraction stations for oil/gas; • Offshore oilfields; • Petrochemical industry or industrial applications; • Gas pumping in pipelines and storage tanks; • Gas supply systems of gas turbines. Every story has a beginning. For COMOTI, the adventure began in 2002, when it achieved a gas compression equipment that use a screw compressor purchased from GHH RAND company. Over time, the cooperation relations with GHH have passed from the stage of execution of various components of compressor to the stage of granting, in 2010, of license to manufacture screw compressor with oil injection from CU range, respectively for three type of compressor CU64D+G, CU90G and CU128G with maximum discharge pressure of 26 bar (abs.) and flow rates between 85 and 920 m3/h. Requests coming from both internal and external partners have determined involvement of COMOTI in a new partnership with GHH (as supplier of rotors), in order to develop a new family of screw compressors with discharge pressure between 40 and 45 bar abs. and flow rates up to 5000 Nm3/h (with suction pressure at 4.5 bar abs).

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2. New family of screw compressors achieved by COMOTI 2.1 Screw compressor CHP 220 To achieve this new type of screw compressor COMOTI developed a partnership with the City University London, which, through the Centre for Positive Displacement Compressor Technology led by Professor N. Stosic, managed to devise a procedure for the optimization of screw compressor type CHP 220 and designed a new improved profile. “N type” profile used by City University was obtained by a patented process. The “N” profile design is an optimum between rotor tightness, small blowhole area, large displacement, and short sealing lines, small confined volumes, involute rotor contact and proper gate rotor torque distribution, together with high rotor mechanical rigidity. Is thus obtained a screw compressor with the parameters improved significantly compared with other rotors of the same dimensions work under similar conditions: • increase by about 6.5% of flow; • a decrease of about 2%, 2.5% to specific power.

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Rotor configuration is determined by the number of lobes in the main (male) and gate (female) rotors, for this case, a 4-5 configuration means 4 lobes in the main and 5 lobes in the gate rotors. This configuration of the rotor in conjunction with the report of the rotor length and diameter (L / D = 1.35) offers the advantage of increased compactness and rigidity of the rotor (high moment of inertia) and improves rotor and casing processing compared to other configurations (5-6 or 5-7). The rotors manufacturing was achieved by the company GHH Rand. Nominal parameters are: • Inlet pressure 4.5 bar abs. • Delivery pressure 45 bar abs. • Flow 5000 Nm3/h • Electric drive 700 kW

CHP 220 assembly – side view

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CHP 220 on test stand

Screen capture with parameters of compressor CHP 220 during test

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2.2 Development of licensed screw compressor range To achieve a screw compressor with high discharge pressure were taken into account the following aspects: • casing redesign and change of their material according to API 619; • stress and strain calculations using finite element analysis; • improving the solution of taking over the axial forces; • improving the constructive solution for rotors in their discharge area. 2.2.1 Screw compressor type CU 90 M • Inlet pressure 4÷9 bar abs. • Delivery pressure max. 45 bar abs. • Flow 1000÷1800 Nm3/h • Electric drive 132÷250 kW

CU 90 M assembly – isometric view

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In the next pictures it can see what are the main differences between these two types of compressors.

Cylindrical head shaft

Single seal Discharge flange

CU 90 GHH compressor

CU 90 M COMOTI compressor

Double seal

Conical head shaft

Discharge flange

Suction flange

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Screen capture with parameters of compressor CU 90 M during test

CU 90 M on test stand

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2.2.2 Screw compressor type CU 64 GM • Inlet pressure 4÷9 bar abs. • Delivery pressure max. 45 bar abs. • Flow 600÷1600 Nm3/h • Electric drive 75÷160 kW

CU 64 GM assembly – side view

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CU 64 GM on test stand

Screen capture with parameters of compressor CU 64 GM during test

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3. Quality System 3.1 COMOTI operates under the rigors of an integrated quality management system (Quality, Environments, Health and Occupational safety) according to SR EN ISO 14001 and SR OHSAS 18001, providing eco-friendly products that meet the quality, reliability and operational safety requirements. In accordance with European Directive 94/9/EC (ATEX), the ATEX certification for these products is performed by a notified organization - INCD INSEMEX Petroşani – and according to following harmonized standards: SR EN 1127-1 - Explosive atmospheres - Explosion prevention and protection. Part 1: Basic concepts and methodology; SR EN 13463-1 - Non-electrical equipment for use in potentially explosive atmospheres - Part 1: Basic method and requirements; SR EN 13463-5 - Non-electrical equipment intended for use in potentially explosive atmospheres - Part 5: Protection by constructional safety 'c'; SR EN 13463-6 - EN 13463-6:2005 Non-electrical equipment for use in potentially explosive atmospheres - Part 6: Protection by control of ignition source 'b'; SR EN 13463-8 - EN 13463-8:2003 Non-electrical equipment for potentially explosive atmospheres - Part 8: Protection by liquid immersion 'k'.

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3.2 GHH-Rand license

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