3.1　General Requirements

3.1.1　The rotary machines used for petrochemical service shall be designed and constructed for a minimum service life of 20 years（excluding the wearing parts），and the uninterrupted operation cycles shall be no less than the service years indicated in Table 3.1.1.

Table 3.1.1　Uninterrupted Operation Cycle of Rotary Machines Used for Petrochemical Service

Note:in special conditions，the uninterrupted operation cycle of rotary machines may be mutually agreed.

3.1.2　The rotary machines shall be within the scope of their design and manufacture experience，and at least one same or similar model rotary machine have been running successfully under same or similar operating conditions for two years or more.

3.1.3　On-lines pares shall be provided for the pumps，medium-and small-size fans/blowers，instrument air centrifugal compressors and reciprocating compressors in continuous operation，one on-line spare shall be provided for the single pump（rotary machine），and at least one on-line spare shall be provided for several pumps（rotary machines）arranged in parallel operation.Off-line spare parts shall be provided for the agitators in continuous operation.On-line spares may not be provided for the large-size fans/blowers，centrifugal compressors and gas turbines，but long term parts should be provided as critical/capital spare parts for them.

3.1.4　When the medium contain H2S，chloride or other components that may result in stress corrosion，or the medium contain any components that may be subject to reaction with copper or copper alloy，they shall be indicated in the datasheets or technical requisition documents.The construction materials of rotary machines shall be suitable for the requirements for these medium.

3.1.5　The complete unit of rotary machine shall include all equipment，pipes，valves，electrical，instrument and control systems within the scope of supply.

3.1.6　The design pressure of steam jacket and cooling water jacket shall be no less than the maximum working pressure of their respective external supply systems.

3.1.7　The minimum temperature rise at the water side of cooling system shall comply with the utilities conditions.When gas cooler is used，the minimum temperature rise shall be at least equal to 8℃，and when oil cooler is used，the minimum temperature rise shall be at least equal to 4℃.

3.1.8　The general design of rotary machines shall be easy for operation and maintenance，the construction design should allow easy dismantling of rotors without removing the process pipes on the casings，and the engineering design shall provide sufficient spaces and accesses and shall be easy for equipment and pipe maintenance，hot insulation，cold insulation and personnel protection insulation installation.

3.1.9　The rotary machines should be shipped as complete units.For oversize equipment，they may be shipped by segments.For fragile parts，they may be removed after test，and then shipped in separate，and the mating surfaces shall be marked.All fragile parts shall be specified in the installation manuals.