10 construction-facilities petrochemicals

Buildings Practice Facilities Plants/PetrochemicalsChapter 10

ConstructionIntroduction1 Contractor shall carry out all construction work in accordance with procedures and

methods prepared during detail engineering for all construction trades in accordance with project specifications.

2 All details of facility shall comply with ‘approved for construction’ drawings, specifications/all applicable engineering and technical standards and codes.

3 Contractor shall plan construction in such a way that facility can be built, pre commissioned, commissioned and started up in sequence.

4 In particular, contractor shall commission utilities well in advance for purpose of startup of facility.

General Construction Requirements1 Facility for project shall be provided and constructed in a safe, timely and reliable

manner. 2 Latest construction techniques and equipment shall be used to provide an effective

construction approach to achieve scheduled completion date. 3 During construction of facility, contractor shall comply with company/client safety and

work permit procedures/enforce a set of approved safety rules and precautions for work at construction sites.

Contractor construction work shall include, but not be limited to following requirements:1 Obtaining all approvals and permits for work per company/client regulations.2 Establishing construction site safety rules and providing a safety manager, officers and

staff for work.3 Providing construction personnel, temporary works, temporary facilities and other

facilities required for construction, in order to ensure proper performance of work in accordance with contract schedule from commencement of work to its completion.

4 Contractor shall fully adapt its organisation for each specific phase of work to fulfill all contract requirements and accordingly, shall mobilise, develop and maintain overall functional organization/corresponding resources including when, where and as necessary, by providing additional means.

5 All construction equipment, scaffolding, tools, protection, testing and control equipment, auxiliaries, consumables etc. and personnel (including management and supervision), necessary for performance of work in particular, for handling, transportation, warehousing, prefabrication, erection & testing.

These shall include, but not be limited to:1 Provision of maintenance and running of construction equipment2 Provision of safety equipment and tools (small & power both) for personnel and works3 Provision of mechanical equipment and material necessary, for working in water free

conditions, whatever volume or flow it could be4 Provision, storage, distribution and disposal of consumables (oil, lubricants, gas etc.) &

auxiliary materials (planks, timbers, tarpaulins etc.)5 Provision of scaffolding and protection material from unsafely working accidents6 Provision of materials and apparatus for technological laboratory to test materials,

welders/provision of materials and apparatus to test all completed works7 Safety equipment, whatsoever required for respective activities8 Providing accommodation, lodging and transportation for construction personnel

pertinent contractor, subcontractors and vendors.

of 14 2012 Int. P Eng Suraj Singh


Construction9 Preparing construction procedures for work, which shall be submitted for company/client

approval, while in addition contractor shall ensure:10 Preparation of inspection and test plan (ITP) in compliance with above and contract

conditions to be submitted for approval to company/client11 Execution and recording all test and inspection for equipment/materials and work12 Verification/checking conformity of work and provide records13 Issuance of construction method statement per company/client request (for critical works)14 Contractor must be able to prove at all times that quality of supply incorporated within

work, complies with quality specified in contract.15 Managing, coordinating and supervising work of subcontractors and vendors to ensure

that work is performed on schedule and in accordance with quality and safety requirements.

16 Preparing detailed schedules for work in accordance with execution 17 Programme, regular monitoring of time schedule and making appropriate adjustments to

obtain most efficient usage, taking into account interfaces with telecommunication, electrical authority, MMAA and other parties involved.

18 Providing detailed manpower and construction facilities deployment charts.19 Providing schedule and progress reporting in accordance with requirements of contract:20 Progress reports (daily, weekly, monthly, flash etc.)21 HSE report in details regularly22 Work schedules required at all levels from level 1 to level 523 Physical progress reports reflecting actual status of progress on site24 Construction equipment status reports25 Supplies status reports, un priced copy of purchase orders, certificate of origin of all

equipment and materials to be provided by contractor.26 Monthly status of material taken over by contractor (material status & delivery schedule)27 Updating of list of work items drawings28 Providing a quality assurance plan and developing quality control procedures.29 Providing all temporary facilities required for work:30 Erection, maintenance, dismantling and removal of all temporary site facilities, including

all complementary works, civil, electrical etc. inside allocated areas.

It includes, but is not limited to:1 Contractor and subcontractor’s site facilities, such as office, workshop, warehouse,

shelter, sanitary building, storage area, concrete or bituminous mix production plant, etc. including all complementary works, civil, raw/potable water and sewer networks, power supply etc. inside allocated areas, lighting of works areas

2 Temporary works to prevent personnel from injuries and/or properties from damage3 Scaffolding and safety equipment necessary for works. 4 Such scaffolding and safety equipment must be left in place as long as, necessary to allow

inspection, tests and control5 Contractor and subcontractor office facilities6 Company/Client office facilities7 Contractor and subcontractor warehouse

All site utilities for contractor need to include, but not be limited to:1 Power supply2 Power supply cost (for contractor use)3 Water supply (potable, raw)



Construction4 Potable water supply cost (for contractor use)5 Potable or raw water supply cost (for construction works use except for piping hydro test)6 Raw water supply cost (for piping or equipment hydro test)7 Treatment of raw water for hydro tests8 Nitrogen supply for pre commissioning works9 Nitrogen supply for works including cost (for contractor use)10 Air supply11 Air supply costs (for contractor use)12 Disposal of all sewer and wastewater, rubbish and trash13 Fuels and lubricants for temporary facilities and construction equipment14 Maintaining construction records in formats to be submitted for company/client approval.15 Ensuring timely mobilisation of vendors' representatives and/or other specialists and their

retention at construction site for required duration.16 Providing QA QC and inspection services for work. 17 This shall include, but not be limited to civil, structural, welding, piping, mechanical,

electrical, instrument and painting inspectors.18 Contractor shall mobilise a third party inspection agency (TPI) to perform following

requirements, such as NDT and interpretation-Civil lab testing-Load tests19 All other required personnel and QA/QC inspectors shall be provided by contractor.20 Contractor shall mobilise adequate level of inspectors. 21 QA/QC procedures and equipment shall be subject to company/client’s approval.22 Maintaining and operating an adequate system of controls pertaining availability of

drawings and specifications with latest revisions at all places, where work is performed.23 Maintaining and operating an adequate material control procedure at all places, where

work is performed.24 Assisting company/client with technical safety reviews to confirm that facility can be

operated, maintained, shutdown and started up in a satisfactory manner. 25 Managing field queries, field changes and revision of drawings. 26 Preparing a complete set of datasheets, specifications and as built drawings. 27 Preparing rigging studies as required.28 Mobilize in a timely manner construction management team to construction site in

nation.

Contractor should in particular submit:1 Detailed construction execution plan taking into account all site constraints2 Mobilisation plan in details3 Scaffolding plan including resources, technical solution proposed, material specification

and scaffolding management (HSE) procedures4 Nominative organisation charts down to, but excluding foremen level and corresponding

CV's included for all key personnel to supervise on site & controlling coordination5 List of resources assigned to work:6 Personnel per category, nationality and split between different disciplines/significant

activities within each discipline, as required in particular exhibits7 Construction equipment (type and quantity)8 Allocation of site temporary facilities and storage areas to contractor9 Site temporary facilities detailed layout drawing and descriptions10 Site storage areas (raw materials, finished materials) detailed layout11 Provide housekeeping personnel for work on basis of one cleaner per 25 persons. 12 Reinstate existing roads, track, channels and secondary roads to original conditions and



Constructionspecification.

13 Arrange for protection of turtle eggs during construction.14 Contractor shall do whatever is necessary to take care of rock, obstructions or/and

unsuitable materials present within construction site.15 Contractor shall dismantle and remove X #s temporary cofferdam and take ownership of

sheet piles and deliver precast units to plant port as directed by company/client. 16 Contractor shall within 30 calendar days from contract effective date, supply and install

its dewatering system in cofferdam constructed by other contractor.17 Contractor is aware about buried services (pipe, cable and duct) within battery limits and

that coordination with company/client/plant (for as built drawings) shall be required during detailed design and that hand excavation also, required in certain areas during construction, unless confirmed in writing by company/client.

18 Protection and preventive maintenance of material handed over to or supply by contractor per state of art and supplier’s recommendations.

Contractor shall be responsible for effecting following requirements:1 Respect of site constraints (safety, units in operation, site layout, location and setting up

temporary site facilities etc.)2 Protection of all tracks and roads used by contractor and subcontractor and located in

vicinity of site3 Make good to original condition at contractor's cost of parts damaged by contractor or its

representatives (concrete, steel structures, piping, instruments, painting etc.)4 Installation, dismantling and removal of all temporary protection devices used by

contractor to protect personnel, structures, piping, facilities and equipment on site5 All precautions and measures to avoid damage caused by traffic, dust, noise and all other

causes that may affect personnel, buildings, equipment or goods located nearby

Contractor shall be responsible for effecting following requirements:1 Daily collecting and removal of all materials used within works areas, such as iron scrap,

debris etc2 Disposal of refuse and debris in relevant authorised dumps3 Housekeeping of areas allocated to contractor to keep site & offices tidy4 Daily cleaning of site, all tracks and roads used by contractor, which are located in

vicinity of site. 5 This also, includes spraying of water if required, for stabilising dust. 6 Destruction of temporary paving and concrete works including removal, transportation to

an authorised dump and leveling of concerned areas7 Returning site to a suitable condition at completion of work

Work Permits Procedures and Regulations1 Contractor shall comply with company/client work permit procedures, regulations

appended within appendix and with electrical authority/plant work procedures, when working at plant and at NCC.

Following Company/Client Regulations shall also, apply:1 Electrical safety instructions 2 Plant security guidelines3 Consolidated permit to work system in plant industrial city.4 Company/client lifting equipment regulations



Construction5 Plant mutual aid programme6 Regulations for disposal of dredged materials within plant industrial city7 Health, safety and environment plan in conformance with company/client requirements

Construction Site Preparation and Construction Site Access1 Contractor shall accept construction site work ‘as it is’ and complete excavation work as

required, dispose of ground and rain water, provide complete required infrastructure, including additional temporary fencing, security gates for facility, roads, ditching, sewers and more generally, be ultimately responsible for finalization of, whatever construction site preparation work required.

2 Construction site preparation shall include construction site clearance, rough grading, general earth works, leveling to grade selected, temporary boundary fencing, opening of roads on construction site, excavation and blasting, if required.

3 Contours are provided, but ultimate responsibility for final contours shall be obliged by contractor.

4 Site preparations and transport of quarried construction materials shall be carried out in an environmentally, acceptable manner, so as not to impact surroundings.

Construction Facilities 1 Contractor shall obtain permission from plant for access to areas, close to construction

sites for offices, lay down, fabrication yard etc. 2 Contractor shall provide office facilities to company/client as specified in appendix.3 All utilities required in all areas during execution of work shall be obligatory

responsibility of contractor.

Safety and SecurityContractor shall assume sole responsibility for safety (including fire prevention) of work. Scope of safety shall include, but not be limited to following requirements:1 Providing safety and fire prevention procedures at construction site.2 Providing evacuation and first aid facilities in accordance with local regulations, for all

personnel assigned to construction site.3 Providing adequate safety management and personnel, safety procedures, safety plans,

safety organization chart, safety instructions, safety talks and ensuring that these procedures together with company/client's requirements are promulgated and enforced.

4 Supervising all personnel assigned at construction site ensuring that they abide by safety programme.

5 Generally, providing one safety officer for every 50 persons shall work.6 Regularly, verifying adequacy of subcontractors' craneage, rigging and scaffolding to

function safely and reliably.7 Ensuring safety regulations and keeping safety records all times.8 Reporting to company/client on status of planning and implementation of activities to

ensure safe construction and operation installations.9 Issuing safety reports to company/client as specified in appendix.10 Providing security gates and surveillance at various sites.

Extent of Construction Scope of Work1 Construction work includes, but is not limited to activities described hereinafter.2 Included descriptions are not exhaustive, but are indicated solely for contractor’s

guidance, which shall be read to be continued within context of present scope of work



Constructiondocument.

3 Above ground piping work prefabrication and erection including material management, prefabrication/erection works including all tests and control and flushing operation.

4 Instrumentation work including installation, connection, testing of all material and equipment in units/in technical rooms/control rooms including loop testing from control systems such as DCS, PLC to each local instrument.

5 Electrical work including installation, connection, testing of all material and equipment in units/in substations including testing and energising.

6 Site preparation and road, piling, underground piping, civil works/building works including earthworks, road, site preparation including fencing works, drainage, pressurized underground piping erection, gravity pipe networks, all concrete works such as foundation, structure, paving building construction including detailed design/supply/erection of secondary works and HVAC systems and all related tests and controls.

7 Steel structure fabrication and erection works including detailed design, supply, fabrication, transportation, erection and all associated tests and controls.

8 Insulation works of piping and equipment including supply and erection of all type of insulation and associated tests and controls.

9 Painting works of piping, steel structure and equipment including supply and application on field (or on shop for piping elementary components) of paint on, but not limited to steel structure, piping and equipment.

10 GRP piping prefabrication and erection including material management, prefabrication/ erection work including all tests and controls and flushing operation.

11 Hoisting, mechanical assembly of all equipment and material including erection work, alignment, test and control.

12 Heating, ventilation and air conditioning including installation, connection testing of all material and equipment.

13 Storage facilities including detailed design, supply, fabrication, transportation, erection and all associated tests and control.

14 Firewater tank, erection of fabrication tank, site construction, assembly and all associated field tests.

Pipeline construction/pipeline routing introduction1 Pipeline construction scope shall compose of all works in relation to piping/pipeline

construction as outlined below and as defined by FEED specifications, drawings & documents.

2 Contractor shall oblige to be responsible for identifying all disciplines in extent of work requested for piping/pipeline construction activities.

3 Pipeline construction activities shall include, but not be limited to following activities.a Installation of GRP piping manifolds at pump houses.b Installation of all piping for pump houses.c Installation of all utility piping in intake area.d Installation of all piping for packages including electro chlorination unit.e Installation of piping (above ground/buried) for fresh water firewater system.f Installation of extension of seawater, firewater system (above ground/buried) to cover

all new plots/facilities.g Installation of cooling water supply pipelines (above ground/buried) from pump

house to end user battery limits.h Installation of cooling water return pipelines (above ground/buried) from end user



Constructionbattery limits to receiving basin.

1 Note that ‘Installation’ includes all pipe, joints, valves, fittings, flanges, spectacles, supports, anchors, manholes, inspection holes, vents, drains, sumps, pits, welding, jointing, non destructive/destructive testing, inspection & repair, trenching, lowering, backfilling, crossings of pipelines/utilities/roads, ROW preparation, hydrostatic testing, any temporary supports etc.

2 Contractor shall make due allowance in its schedule and management of its construction activities for other ongoing third party activities at construction site and surrounding area.

3 Contractor shall be responsible for contacting and obtaining necessary permissions from all relevant governmental authorities and third parties before construction works commence.

4 Contractor shall obtain all necessary permits and consents in compliance with requirements.

5 Contractor shall verify location of all existing installations and services to satisfaction of company/client and applicable service owners.

6 Contractor shall allow governmental authorities and third party service owners, all possible access to inspect and witness works execution in vicinity of installation(s) and conduct such works in accordance with contract requirements.

7 Contractor shall meet all its obligations in this respect in a timely manner, such that there is caused no delay on works.

8 Contractor shall utilize only, approved certified testing laboratories for all destructive testing to be carried out on works under construction.

9 If contractor wishes to provide testing facilities on construction site to carry out such destructive testing, facilities shall be certified in accordance with relevant international standards and also, approved.

10 Contractor shall note that works include at least receipt, transportation, handling and storage (in addition to all other construction activities) of all items included on novated purchase orders by company/client to contractor.

11 Contractor shall comply with all company/client instructions with respect to these particular items and its delivery to site.

Following drawings form part of appendix of this document.1 Plot plan.2 Pipeline routing plans including sections and details.3 Survey drawings for cooling water and firewater route corridors.4 Contractor shall be responsible for verification and confirmation of all FEED

deliverables.5 Contractor shall initially, locate existing pipelines/other facilities and place barriers to

prevent its personnel or equipment from working over and damaging existing pipelines/other utilities.

GeneralContractor’s scope of work shall include, but be not limited to following requirements:Installation of piping systems generally indicated on P&ID’s, preliminary plot plans and

preliminary main routing plans included within contract.1 All material handling, craneage and scaffolding2 All prefabrication of piping systems3 All erection of piping systems, including tie ins and crossings4 All prefabrication and installation of supports including material supply



Construction5 All welding requirements6 All heat treatments, if applicable7 All non destructive testings8 All hydro testing, construction cleaning, draining and drying of piping systems.9 All chemical cleaning, if so applicable.10 All reinstatement of works11 All nitrogen or air testing, when & where so required12 Performing all inspections and tests onsite13 Providing all weather protection measures, when and as required14 Bolt tensioning15 Provide all pipe spools and pipe fittings necessary for hydro test16 Provision and installation of locking devices to lock open certain valves, where necessary

Scope of Modification Works1 All works necessary for implementation of modifications at various sites or alternatively,

in workshops or other designated locations.

Scope of installation works1 Installation at a definite location of equipment for project, activities to include setting,

first alignment, tightening and tensioning of equipment foundation bolts.2 Installation of all equipment/packages etc.3 Provide support structure to all equipments4 Second alignment after final connection of piping5 Provision and installation of services items, such as temporary blinds, caps, grease etc.6 Provision of protection against mechanical damage and damage from weather conditions.7 Performing initial fill of lube oil, grease etc.

Prefabrication of Piping1 Contractor shall perform a site survey to ensure spooling of correct dimensions suitable

for erection at site and determination of field welds. 2 Contractor shall prefabricate piping in quality controlled conditions (offsite) to a

maximum extent possible.

Scope of prefabrication work shall include, but not be limited to:1 Transport, receipt inspection, storage, conservation, handling and administration of all

materials at contractor’s prefabrication shop location.2 All prefabrication, hydro test (including supply and disposal of test water) NDT works

and send it to painting yard for blasting/painting.3 Transport (including loading and offloading) of prefabricated elements from

prefabrication shop to worksites.4 Tagging all spools with isometric number and storing it in a safe designated area at

erection site.5 Erection of piping works6 Access to existing facilities shall not be interrupted. 7 Future corridors reserved for other facilities shall not be encroached. 8 Temporary access to existing facilities/roads shall always be maintained.9 Prepare work packs and identify piping spools for erection.10 Erect rack structure, supports etc. and align11 All erecting, testing and re instating of piping systems, including supports (both



Constructiontemporary & permanent).

12 All bolt tensioning required according to pipe installation work specifications.13 Installation of temporary strainers and removal after flushing.14 Arrange and provide all testing and drying facilities15 Supply, installation and dismantling of temporary supports.16 All other necessary activities, such as marking, re stamping, inspections, documenting,

establishing procedures, obtaining approvals from company/client etc.17 Surface protection, priming, painting, touch up etc.18 Fabrication, erection and installation of U-bolts, pipe clamps and/or other restraining

devices necessary for work.

Pipe protectionAt each location, where pipes cross roadways at an elevated level inside plant areas,

permanent bunting poles with warning signs shall be erected.1 At all such locations, where pipes run adjacent to plant roadways/and at all locations,

where new facilities are being constructed or modified, permanent ‘armco’ type barrier protection shall be provided.

2 Installation of GRE/GRP piping system3 Construction supervision4 Coordination with all GRP vendors/suppliers at site5 Arrange meetings with other contractors (interface) to avoid fouling with existing

facilities. 6 Access to existing facilities shall not be interrupted. 7 Future corridors reserved for other facilities shall not be encroached. 8 Temporary access to existing facilities/roads shall always be maintained.9 On/off loading and storage10 Installation of piping system11 Insertion of all sealing rings, gaskets and locking devices12 Make up of all laminated/bonded joints and coupled connections13 Acceptance of anchor bolts14 Acceptance of trenching backfill and compaction15 Acceptance of each system as ready for hydro test16 Hydro test of spools/joints and double bell couplers, prior to system hydro test.17 Guarantee of successful hydro test18 Above acceptance shall be signed by site representative of GRE/GRP manufacturer prior

to contractor proceeding with subsequent stage of construction in each case.

Trenching Contractor shall carry out pipe trenching in accordance with following requirements:1 Contractor shall perform all required trenching/excavation either using machine or by

hand, including rock hammer and blasting, where required and provide all necessary shoring, sheeting, dewatering, protection, stabilization and maintenance of trenches, including supply and installation of temporary crossings over excavation, if required.

2 Contractor shall assume all necessary precautions to protect all existing facilities encountered during performance of work.

3 Where excavation is required within three (3) meters of some gas, oil, water, sewer, electrical, telephone or power lines, contractor shall give company/client ample notice (at least two weeks in advance) for each work permit and follow company/client standard practice.



Construction4 Contractor shall also, arrange for permits from various local authorities.5 Contractor shall assume special precautions, when working parallel and within five

meters of existing pipes or below overhead lines. 6 All work in existing facilities areas shall be carried out adhering to company/client work

permit procedures.

Welding and Radiographic InspectionContractor shall carry out welding and radiography inspection in accordance with following

requirements:1 Contractor shall provide all services, materials, and equipment necessary to develop and

submit to company/client for approval all required welding procedure qualifications, welder qualifications, for production welding for mainline, installation of scraper traps, installation of mainline valves and all other welding activities.

2 Contractor shall check all controlling dimensions and pipe roundness prior to installation, to avoid delay.

3 If discrepancies exist, contractor shall notify company/client immediately, in a timely manner of its corrective action for approval.

4 Ten percent (10%) radiographic examination of all welds shall be performed using X-rays.

5 Weld maps shall be prepared and maintained by contractor and turned over to company/client at completion of work.

6 10% Radiography shall be taken as basis, however detailed NDT requirements should be reviewed during execution of work on case by case basis, depending upon criticality and nature of services.

7 All radiograph films and test results shall be protected and stored by contractor in a dry, secure place, until are handed over to company/client at completion of work, which films & test results should be packed in good condition for permanent storage.

Road, Track and Existing Pipeline CrossingsContractor shall carry out pipe, road, track and existing pipelines crossings according to

following requirements:1 Contractor shall construct all roads, tracks, and crossings on existing pipeline and other

facilities as required in accordance with approved drawings and in full compliance of all local road requirements and regulations in nation.

2 Contractor shall maintain traffic flow and movement of personnel during installation of road crossings.

3 Where road crossings are performed by ‘open cut’ method, detours shall be provided.4 Contractor shall obtain company/client approval for design of detours. 5 All detours shall be paved. 6 After completion of crossing, contractor shall reinstate roads and surrounding area

including detours to original condition and to satisfaction of company/client

Pipeline Cleaning1 Contractor shall ensure that internals of pipeline are thoroughly, cleaned and inspected

prior to hydrostatic testing in accordance with approved project procedures.

Hydrostatic Pressure Testing1 Contractor shall perform hydrostatic pressure testing of all piping in accordance with

approved project specifications and procedures.



ConstructionTie Ins

General Requirements1 Preparation of a detailed tie in index and schedule2 Obtaining approval from company/client for all tie in locations.3 Marking tie in locations at site for company/client approval.4 Provisions of all spades, gaskets and bolts for tie in works.5 Removal of piping, if necessary6 Prefabrication of tie in piping7 Connection of tie in piping, including cutting and beveling.8 Non destructive testing (NDT) of tie in location prior to and on completion of works.9 Hydro testing and drying of relevant part of existing and new piping system.10 Repair of coating on existing system.

Tie Ins during Shutdowns1 Contractor shall furnish all equipment, materials, personnel, supplies, and consumables

necessary for performing all tie in. 2 Contractor shall confirm adequacy of all tie in.3 Contractor shall plan and schedule tie in activities to implement during planned plant

shutdown periods or, where it is not possible, to minimise plant shutdown required.4 Contractor shall submit a procedure/method statement for each of tie in activity for

company/client review and approval including, but not limited to following requirements:5 Procedure-method statement-work execution plan-material for permanent incorporation-

consumable requirement-safety consideration-hazard identification-operational impact6 Contractor shall tag (physically mark on site) each tie in location, after it is confirmed.7 Contractor shall produce an isometric drawing with complete material list for each tie in.8 Contractor shall ensure all materials are available for tie in work prior to submission of

request to commence tie in works.

Final Cleanup1 Project area and all other areas affected during construction shall be maintained clean and

free of environmental pollutants. 2 Daily cleaning of construction site shall be performed.3 At completion of work, construction areas shall be restored as close as, possible to

respective original conditions. 4 It includes construction site, staging and storage areas, excavated material stockpiles,

existing structures affected as well as, all other areas disturbed by contractor during construction.

Cathodic Protection1 Contractor shall install cathodic protection system, where necessary as indicated within

cathodic protection specification/scope of work document and provide post installation testing, interference testing and preparation of as built drawings with final report.

Mechanical Completion1 Contractor shall plan in conjunction with company/client to achieve mechanical

completion in accordance with execution programme to be ready for pre commissioning activities.

2 Mechanical completion activities are linked in exhibit of appendix.



ConstructionNavigation1 Without in anyway limiting or detracting from effect of any other clause hereof,

contractor shall conform to byelaws/regulations concerning navigation and shall obey orders of, whoever authorized and competent officer or agent of government or port authority in reference thereof.

2 Contractor’s operations must be conducted in such a manner that these neither interfere with, nor endanger either use of working of waterways, anchorage wharves, jetties, causeways, dolphins and approaches there to, whether belonging to company/client or to persons or whatever water borne traffic, except by prior arrangements with company/client representative and port authority.

3 Contractor is to subject full details of all operations that may cause an interference with shipping to company/client’s representative for approval at least 7 days, before event and should make such modifications, as company/client’s representative may require in order to keeping such interference to a possible minimum practically.

4 Normal movement of craft within harbour shall be notified to marine operations. 5 All crafts shall be fitted with VHF radios.

HRW Hydraulic Study Notes ConclusionsContractor shall consider HRW studies’ conclusions as given below.1 This technical note has described a design review and a computational fluid dynamic

model study of proposed plant CCWS pumping stations 2 Study has considered most recent estimates of design flow rates, comprising -------m3/hr

from pumping station ------- m3/hr from pumping station and ------------ m3/hr from pumping station.

3 Design flow conditions at entrance/inlet to pumping station 4 Water levels at pumping station entrance and approach flow patterns considered in

analysis took account of flow into pumping station. 5 Minimum water level of -0.95M NHD corresponds to a head loss of only 0.07M in

channel. 6 Approach flow patterns are direct and well behaved.7 Review of layout in relation to design guidelines etc.8 Typical maximum approach flow velocities to bar screens are considered to be within

acceptable limits in relation to potential turbulence levels at bar screens.9 In worst case (i.e. for PH) at maximum flow, velocity in double entry channels at drum

screens shall be typically 0.86M/S. 10 It is a little high relative to HR Wallingford's experience of other installations and it

would be appropriate to confirm with relevant screen vendors that a maximum approach velocity of some 0.8-0.9M/S is acceptable in channels approaching drum screens.

11 In worst case (when one screen train is out of service), maximum velocity leaving screen units shall be approximately 0.8M/S.

12 It is considered a little high in relation to size of fore bay area as confirmed by CFD model.

13 Flow modification measures (e.g. baffles or columns) are likely to be required in fore bay to ensure satisfactory flow patterns under adverse combinations of screens and pumps in operation.

Submergence of pumps1 Available submergence and proposed elevation for pump bay invert (-9.50M NHD) are

considered satisfactory in relation to required submergence conditions for minimisation



Constructionof free surface vortices.

Overall dimensions and internal structures1 Proposed overall layout and dimensions for screen chambers is considered satisfactory

for FEED. 2 It would be recommended however, that required width of each screen chamber element

should be subject to further review/detailed design during EPC following identification of actual screen vendor and actual screen dimensions.

3 In case of PH#, initially designed pump chamber width of 5.0M is smaller than standard guidelines would suggest.

4 Preliminary enquiries with pump manufacturers have indicated that a pump chamber width 5m would be acceptable (even based upon a bell mouth diameter of 2.7m).

5 Taking it into account, proposed 5m width for each pump chamber is considered satisfactory for FEED.

6 It would be recommended however, that required width of each pump bay should be subject to further review/detailed design during EPC following final confirmation of actual pump vendor and actual bell mouth diameters.

7 Initial design for pump bays provides for a ‘standardised’ pump bay length 10m, which is satisfactory with respect to pumps for PH and PH, but short relative to standard guidelines in case PH#.

8 Proposed ‘standardised’ distance from rear wall of a pump bay to pump centre line 2.2m is in accordance with standard guidelines.

9 In general terms, splitter/benching, corner fillets and curtain wall arrangements are considered appropriate vortex suppression devices/methods.

10 On basis of ‘standard best practice’, it is considered that these features should be included within pump bays as these shall help serve inhibit severe surface and subsurface vortex formations.

11 Free passage of air must be allowed at top of pump bays and other semi enclosed areas of pumping stations.

12 Roof slab is expected to be clear of water surface, even for extreme water level/wave conditions (notwithstanding possible transient water levels in intake channel that might result from pump startup or trip scenarios).

13 Possible improvements identified for testing in CFD model resulted from short pump chambers in PH and restricted distance between drum screen chambers and pump chambers.

14 Computational fluid dynamics (CFD) model tests15 Simulations have been undertaken for a variety of operational conditions in planned Plant

CCWS pumping station. 16 Calculated water level at entrance to pumping station takes account of flow into phase I

pumping station (PH, and intake channel model demonstrated well behaved approach flow to PH and PH.

17 Therefore, although pumping station computational model does not explicitly, simulate PH, simulations take account of effect of flow into PH.

18 With original design and under adverse combinations of pumps and screens in operation, significant oblique flow with local velocities approaching 1M/S was observed in pump fore bays.

19 Flow in pump chambers under these conditions was asymmetric, locally approaching 0.8M/S and there was observed rotation at pumps.

20 Revisions to design have been proposed, in which columns are introduced at entrance to



Constructionpump chambers to dissipate asymmetric jets.

21 Further simulations have been carried out to show effects on flow patterns. 22 These show significantly, improved flow patterns in pump chambers, but there still

remains scope for further improvement in fore bays. 23 CFD model studies indicate that overall pumping station dimensions are adequate,

subject to provision of dissipating structures described above and optimised during EPC.

Physical model study1 To confirm and extend conclusions of CFD model study, it is recommended that a

physical model study be carried out during EPC phase. 2 It would enable final optimisation of internal layout and confirmation of satisfactory

performance under final design operating conditions. 3 For physical modeling scope of work, refer to appendix-(hydraulic study report)

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10 construction-facilities petrochemicals

Engineering

Transcript of 10 construction-facilities petrochemicals