1 Scope
This Specification specifies the design, manufacture, inspection and test requirements for centrifugal compressor and its driver and auxiliary equipment in petrochemical industry.
This Specification is applicable to engineering design and equipment procurement of centrifugal compressor in petrochemical industry and used in other industries for reference.
This Specification is not applicable to the compressor with fan, blower and gear increaser, nor centrifugal compressor installed and used on ocean platform.
2 Normative References
The following documents contain provisions which, through reference in this Specification, constitute provisions of this Specification. For dated reference, subsequent amendments to (excluding amending errors) to, or revisions of, any of these publications do not be applied. However, the parties whose enter into agreement according to this Specification are encouraged to research the latest editions of these references are applied or not. For any undated references, the latest edition of the document referred to applies.
GBZ1-2002 Hygienic Standards for the Design of Industrial Enterprises
HG20615 Types and Parameters for Steel Pipe Flanges (American System)
SH3406 Steel Pipe Flanges for Petrochemical Industry
API Std 611 General Purpose Steam Turbines for Petroleum, Chemical and Gas Industry Services
API Std 612 Special Purpose Steam Turbines for Petroleum. Chemical and Gas Industry Services
API Std 613 Special Purpose Gear Units for Petroleum, Chemical and Gas Industry Services
API Std 614 Lubrication, Shaft-Sealin9, and Control-Oil Systems and Auxiliaries for Petroleum, Chemical and Gas Industry Services
API Std 616 Gas Turbine for Refinery Services
API Std 617-1995 Centrifugal Compressors for Petroleum. Chemical and Gas Industry Services
API Std 670 Vibration, Axial-Position, and Bearing-Temperature Monitoring Systems
API Std 671 Special Purpose Couplings For Petroleum, Chemical and Gas Industry Services
ASME Boiler & Pressure Vessel Code. Section VIII, Rules for Construction of Pressure Vessels
ASME B16.1 Cast Iron Piping Flanges and Flanged Fittings
ASME B 16.5 Pipe Flanges and Flanged Fittings NPS l/2 through NPS 24
ASME B16.42 Ductile Iron Pipe Flanges and Flanged Fitting
ASME B16.47 Large-Diameter Carbon Steel Flange
ASME B31.3 Process piping
NACE MR-0175 Sulfide Stress Cracking Resistant Metallic Material for Oil Field Equipment
3 Alternative Design
The Vender may provide alternative design favorable to the parties (the Vendee and the Vender) in the aspects of technical and commercial angles. The alternative design provided by the Vender shall cover detailed description, achievement and standards and specifications. The Vendee will assess the alternative design and make a decision on whether to use it.
4 Terms and Definitions
For the purpose of this Specification, the terms and definitions in API Std 617-1995, 1.4 apply.
5 Basic Design
5.1 General
5.1.1 The compressor unit (including auxiliary equipment) shall be designed and manufactured to reach the service life not shorter than 20 years and the expected continuous operation not shorter than 3 years. This is the system design criteria. Machine provided by the Vender shall have the specification within the design and manufacturing experience of the Vender unless otherwise the Vendee makes a written approval and the experience shows that it is reliable to operate at similar application conditions. At least two units of the same type have operated in the same or similar process conditions for two years and the type of unit may be considered to be reliable.
5.1.2 Unless otherwise specified, the Vender shall take full responsibility of the whole unit (including the centrifugal compressor, gear transmission (if necessary), driver, oil system, control, instrument, coupling, relevant auxiliary equipment and pipeline system), and shall be responsible for their reasonable matching. See Annex A for the supply scope of the Vender. Unless otherwise specified, the centrifugal compressor, driver and its auxiliary equipment shall be applicable to outdoor start and continuous operation under specified ambient conditions.
5.1.3 The Vender shall, according to component of process gas given by the Vendee and their physical property of single component, check and calculate specific heat and compressibility factor of multi-component process gas and other physical parameters of gas necessary to design the compressor and shall take final responsibility for the physical parameters of the gas.
5.1.4 Unless otherwise specified, outlet head of compressor shall be free from any negative deviation under specified flow and an appropriate shaft power shall not exceed 104% of expected value of the Vender. The Vender shall ensure the pressure head, flow and power when the compressor operates at rated condition as required by the process; the compressor shall be able to operate at other conditions required and the pressure head shall meet relevant requirements.
5.1.5 Unless otherwise specified, pressure head - flow characteristic curve shall rise continuously by 5% of rated head at least between normal operation point and surge point; at 110% rated flow, polytropic head shall not be less than 85% of nominal polytropic head. If two compressors are so designed to operate in the same condition and in parallel, the head difference on the two curves shall be less than 2% at any point with equal flow.
5.1.6 Cooling water system shall be designed in accordance with utilities provided by the Vendee and shall be equipped with measures to completely empty and evacuate water therein.
5.1.7 See 2.1.6~2.1.8 in API Std 617-1995.
5.1.8 Selection of all the electrical equipment, electrical elements, instrument and other E&I materials and their installation shall meet the requirements of electrical hazards area classification and site ambient conditions specified by the Vendee data sheet (see Annex B).
5.1.9 See 2.1.11~2.1.14 and 2.1.16~2.1.18 in API Std 617-1995.
5.2 Casing
5.2.1 See 2.2.1~2.2.2 of API Std 617-1995.
5.2.2 Casing outrigger shall be vertical to pedestal and the support leg shall be installed with jackscrew in vertical direction and drilled with lead holes. Vertical stainless steel adjustable pad shall be adopted and jacking measures shall be provided to increase or decrease the adjustable pad.
5.2.3 The Vender shall specify maximum permissible working pressure of casing which shall be at least equal to 1.25 times the sum of maximum suction pressure and maximum possible pressure rise when the compressor operates at the combination of all worst conditions required at the trip speed or at least equal to specified safety valve setting value, whichever is larger.
5.2.4 See 2.2.5~2.2.9 in API Std 617-1995.
5.2.5 Axially split casing shall adopt metal to metal connection (with suitable adhesive agent) and be appropriately bolted up. The axially split connection shall not use gaskets (including ribbon-shaped gasket). If agreed by the Vendee, axially split casing may be connected by o-shaped ring or processed circular groove on the connecting flange surface. If the gasket is used for connection between end cover and cylinder, for the radially split casing, the gasket shall be fastened securely. The gasket shall be in a continuous single sheet structure instead of overlapped or stacked type. Gasket material shall adapt to all the specified service conditions. The sealing face shall have roughness Ra at least 1.57 μm.
5.2.6 See 2.2.11~2.2.15 in API Std 617-1995.
5.2.7 The thread of metric system (ISO/M system) should be adopted for the thread of fasteners. Where the thread of British system (UN/UNC system) is adopted, it shall be approved by the Vendee. The general fasteners thread shall meet the following requirements:
a) The bolts shall be arranged such to leave enough space for socket wrench or ring spanner (external thread only);
b) Bolts with inner hexagon head, castellated nut or monkey spanner type bolts shall not be used unless otherwise agreed by the Vendee;
c) Inner casing fastening bolts shall be tightly locked to avoid fall into air duct.
5.3 Interstage Diaphragms and Inlet Guide Vane
5.3.1 Interstage diaphragms and inlet guide vane shall be appropriate at all the specified operating conditions, start, shut-down, tripping, restoring stability and instant surge. Diaphragms shall be such designed to bear the maximum differential pressure likely to be present at any prescribed operating conditions and in case of loading down or shut-down. Internal fasteners (bolt and nut) in gas circuit shall be arranged in place to prevent fasteners from falling into the gas circuit due to breakdown or looseness to damage the compressor.
5.3.2 See 2.3.2~2.3.3 for API Std 617-1995.
5.3.3 Unless otherwise agreed by the Vendee, the axially split diaphragms shall be used and arranged with hoisting bolt hole or other hoisting measures for easy disassembly. The horizontally split compressor shall have all the diaphragms interlocked with casing.
5.3.4 Unless otherwise specified, partition with internal cooling passage shall not be adopted.
5.4 Casing Connections
5.4.1 General
5.4.1.1 The piping design, manufacture, inspection and test shall meet the requirements of one or more standard(s) among HG20615, SH3406, ASME B31.3, ASMEB16.47 and ASMEB16.5.
5.4.1.2 See 2.4.1.1~2.4.1.5 in API Std 617-1995.
5.4.1.3 All the pores on the casing for connecting pipes shall not be less than DN 20 (3/4 in) and shall be subjected to flange connection or processed into a flat face to be studded or welded. Full-penetration butt welding shall be adopted for all. If the pores are less than DN 25 (1 in), they may be provided with enhanced pipe connection with edges reinforced, but threaded connection shall not be used; If the socket welding is adopted as a connection mode, approval of the Vendee shall be obtained.
5.4.2 Connecting Pipe in Main Process Flow
5.4.2.1 Inlet and outlet shall be flanged or connected with stud after processing plane and the pipe orifice shall face the direction as specified in the data sheet. The connecting pipe at inlet and outlet of barrel compressor shall be arranged on the outer casing but not on the end cover. For the radially split cantilever compressor, connecting pipe at inlet and outlet of process gas may be arranged on end cover.
5.4.2.2 Flange pressure class is ANSI 300 at least and meets the following requirements:
a) Face flange is used only for ductile cast iron casing and full raised face shall be provided;
b) See 2.4.2.2.2~2.4.2.2.3 in API Std 617-1995.
5.4.2.3 If the ductile cast iron flange is equal to or less than DN 200 (8 in), it shall be a face flange and minimum thickness shall be ANSI 300 flange thickness in ASMEB 16.1.
5.4.3 Auxiliary Pipe Connection
5.4.3.1 Auxiliary connection includes, but not limited to connecting pipes for air discharge, liquid filling, sewage discharge, cooling water, lubricating and seal oil, flushing, buffer gas and balance disk cavity.
Foreword I
1 Scope
2 Normative References
3 Alternative Design
4 Terms and Definitions
5 Basic Design
5.1 General
5.2 Casing
5.3 Interstage Diaphragms and Inlet Guide Vane
5.4 Casing Connections
5.4.1 General
5.4.2 Connecting Pipe in Main Process Flow
5.4.3 Auxiliary Pipe Connection
5.5 External Force and External Moments
5.6 Rotating Element
5.7 Bearings and Bearing Housings
5.7.1 General
5.7.2 Radial Bearing
5.7.3 Thrust Bearing
5.7.4 Bearing Housings
5.8 Shaft End Seal
5.9 Dynamics
5.9.1 Critical Speed
5.9.2 Transverse Vibration Analyses
5.9.3 Factory Verification of Imbalance Response Analysis
5.9.4 Torsional Vibration Analyses
5.9.5 Vibration and Balance
5.10 Lubricating Oil and Shaft Seal Oil System
5.11 Materials
5.11.1 General
5.11.2 Pressure Parts
5.11.3 Low Temperature
5.11.4 Pressure Components Material Inspection
5.11.5 Inspection of Impeller Material
5.12 Noise
6 Accessories
6.1 Driver
6.2 Gear Transmission
6.3 Couplings and Guards
6.4 Base Plate
6.4.1 General
6.4.2 Base Plate
6.5 Instrumentation and Controls
6.5.1 General
6.5.2 Flow Rate Control
6.5.3 Local Instrumentation and Control Panel
6.5.4 Instrumentation
6.5.5 Alarm and Shutdown
6.5.6 Electric System
6.5.7 Detector of Vibration, Displacement and Bearing Temperature
6.6 Piping System
6.6.1 General
6.6.2 Process Piping
6.6.3 Auxiliary Piping
6.7 Special Tools
7 Inspection and Testing
7.1 General
7.2 Inspection
7.3 Testing
7.3.1 General Requirements
7.3.2 Hydraulic Pressure Test
7.3.3 Impeller Overspeed Test
7.3.4 Mechanical Operation Test
7.3.5 Gas Leakage Test of Compressor after Assembly
7.3.6 Optional Test
8 Painting, Marking, Package and Shipment
8.1 Painting
8.2 Nameplate and Rotation Arrow
8.3 Marking
8.4 Package and Shipment
9 Guarantee
9.1 Mechanical Guarantee
9.1.1 Shaft End Seal Leakage
9.1.2 Bearing Temperature
9.1.3 Bearing Housing Vibration
9.2 Performance Guarantee
10 Vendor's Data
10.1 General
10.2 Quotation Data
10.3 Contract Data
Annex A (Informative) Referenced Scope of Supply
Annex B (Informative) Format of Data Sheet for Centrifugal Compressor
Annex C (Informative) Comparison of Major Materials Used for Compressor
Annex D (Informative) Supplementary Normative References
Annex E (Informative) Comparison of Piping Materials
Annex F (Informative) Vendor’s Drawings and Documentation
Wording Explanation
1 范圍
本規定規定了石油化工用離心式壓縮機及其驅動機、輔助設備在設計、制造、檢測和試驗等方面的要求。
本規定適用于石油化工行業離心壓縮機的工程設計及設備采購。其他行業可參照執行。
本規定不適用于通風機、鼓風機和齒輪增速整體組裝型壓縮機，也不適用于海洋平臺上安裝使用的離心壓縮機。
2 規范性引用文件
下列文件中的條款通過本規定的引用而成為本規定的條款。凡是注日期的引用文件，其隨后所有修改單(不包括勘誤的內容)或修訂版均不適用于本規定，然而，鼓勵根據本規定達成協議的各方研究是否可使用這些文件的最新版本。凡是不注日期的引用文件，其最新版適用于本規定。
GBZ1—2002 工業企業設計衛生標準
HG20615 鋼制管法蘭型式、參數(美洲體系)
SH3406 石油化工鋼制管法蘭
API Std 611 General Purpose Steam Turbines for petroleum，chemical and gas industry services
API Std 612 Special Purpose Steam Turbines for petroleum. chemical and gas industry services
API Std 613 Special Purpose Gear Units for petroleum，chemical and gas industry services
API Std 614 Lubrication，shaft-sealin9，and control-oil systems and auxiliaries for petroleum，chemical and gas industry services
API Std 616 Gas Turbine for Refinery Services
API Std 617—1995 Centrifugal compressors for petroleum. chemical and gas industry services
API Std 670 Vibration，axial—position，and bearing-temperature monitoring systems
API Std 671 Special Purpose Couplings for petroleum，chemical and gas industry services
ASME Boiler ＆ pressure vessel code. Section VIII，Rules for construction of pressure vessels
ASME B16.1 Cast Iron Piping Flanges and Flanged Fittings
ASME B 16.5 Pipe flanges and flanged fittings NPS l/2 through NPS 24
ASME B16.42 Ductile Iron Pipe Flanges and Flanged Fitting
ASME B16.47 Large-Diameter Carbon Steel Flange
ASME B31.3 Process piping
NACE MR—0175 Sulfide Stress Cracking Resistant Metallic Material for Oil Field Equipment
3 替代設計
賣方可以從技術和商務角度，提供對有關各方(買方，賣方)都有利的替代設計。賣方提供的替代設計應包括詳細說明、使用業績和應用的標準規范。買方將評估此替代設計方案，決定是否采用。
4 術語和定義
本規定所用的術語和定義引用API Std 617—1995第1.4條。
5 基本設計
5.1 一般要求
5.1.1 壓縮機組(包括輔助設備)應按照使用壽命至少為20年、預期不間斷連續操作至少為3年進行設計和制造。這是系統的設計準則。除買方作出書面認可外，賣方所提供的機器規格應在賣方的設計和制造經驗范圍內，并且經驗證明在相似的使用場合下使用是可靠的。至少應有兩臺同樣型式的機組在相同或相似工藝操作條件下積累兩年的成功運行經驗，方可認為該型式的機組是可靠的。
5.1.2 除另有規定外，賣方應對整個機組包括離心壓縮機、齒輪變速器(如果需要)、驅動機、油系統、控制及儀表、聯軸器及相關設備和管道系統等負全部責任，并負責他們之間的合理匹配。賣方的供貨范圍參見附錄A。除另有規定外，離心壓縮機、驅動機及其他設備應在規定的環境條件下適用于戶外啟動和連續操作。
5.1.3 賣方應根據買方給定的工藝氣體的組分及各單一組分所固有的物性，核算多組分工藝氣的比熱、壓縮性系數及其他壓縮機設計所需的氣體物性參數，并對這些氣體物性參數負最終責任。
5.1.4 除另有規定外，在規定的流量下壓縮機的出口壓頭不得有負偏差，相應的軸功率不應超過賣方的設計預期值的104％。賣方應保證壓縮機操作在工藝要求的額定工況時的壓頭、流量和功率；同時壓縮機也能在其他規定的工況下正常操作，相應的壓頭應符合規定值。
5.1.5 除另有規定外，壓頭—流量特性曲線在正常操作點到喘振點之間應連續上升，上升幅度至少為額定壓頭的5％，并且在110％額定流量時，多變壓頭不應小于85％額定多變壓頭。對于按同一操作條件設計的欲并聯操作的兩臺壓縮機，兩曲線上任—流量相同點的壓頭差應小于2％。
5.1.6 冷卻水系統應按買方提供的公用工程條件設計，系統應設有能全部放空和排凈的措施。
5.1.7 引用API Std 617—1995第2.1.6～2.1.8條。
5.1.8 所有的電氣設備、電氣元件、儀表和其他儀電材料的選擇，以及他們的安裝都應符合買方數據表(參見附錄B)規定的電氣危險場所分類及現場環境條件的要求。
5.1.9 引用API Std 617—1995第2.1.11條～2.1.14條、2.1.16條～2.1.18條。
5.2 機殼
5.2.1 引用API Std 617—1995第2.2.1條～2.2.2條。
5.2.2 機殼的支腿應垂直于底座，支腳上應提供垂直方向的頂絲并應鉆有引導孔。垂直方向的調整墊應采用不銹鋼，并有頂起措施以方便增減調整墊。
5.2.3 賣方應規定機殼的最高允許工作壓力，該壓力至少應等于最高吸入壓力與跳閘轉速下壓縮機在所有規定工況的最惡劣的組合條件下操作時可能產生的最大升壓之和的1.25倍，或至少等于規定的安全閥設定值，兩者取較大值。
5.2.4 引用APIStd617—1995第2.2.5條～2.2.9條。
5.2.5 軸向剖分機殼應采用金屬對金屬的連接(用可合適的粘接劑)，并用適當的螺栓緊固。軸向剖分的連接不應使用墊片(包括帶狀墊片)。經買方同意，軸向剖分機殼的連接在連接法蘭面上可采用O型環或加工的環形溝槽。徑向剖分的機殼中，當端蓋和筒體間的連接采用墊片時，應將墊片可靠地加以緊固。墊片應為連續的單片結構，不宜采用搭接的或層疊的墊片。墊片材料應適應所有規定的使用條件。密封面粗糙度Ra值至少應為1.57 μm。
5.2.6 引用API Std 617—1995第2.2.11條～2.2.15條。
5.2.7 通用緊固件螺紋宜采用公制(ISO/M制)螺紋，如采用英制(UN/UNC制)螺紋，應經買方認可。通用緊固件螺紋應符合下列要求：
a)螺栓的布置應留有足夠的扳手空間，以便使用套筒扳手或梅花扳手(僅外螺紋)；
b)除非買方同意，不應使用帶內六角頭、帶槽螺母或使用活扳手型的螺栓；
c)內殼體緊固螺栓應可靠地鎖緊，以避免落入氣流通道。
5.3 級間隔板和進口導葉
5.3.1 級間隔板和進口導葉應適于所有規定的運行條件、啟動、停車、跳閘、回復穩定及瞬間喘振。隔板應設計成能承受在任何規定的操作條件下以及降負荷或停車時可能出現的最大壓差。處于氣路中的內部緊固件(螺栓和螺母)應設置在適當位置，以防止緊固件出現故障或松脫進入氣路對壓縮機造成損壞。
5.3.2 引用API Std 617—1995第2.3.2條～2.3.3條。
5.3.3 除非買方同意，隔板應為軸向剖分結構。隔板應設置吊裝用的螺孔或采用其他吊裝措施，以便拆卸。水平剖分結構的壓縮機所有隔板應與機殼互鎖。
5.3.4 除另有規定外，不得采用帶內部冷卻通道的隔板
