SCOPE OF WORK - SATS Ltd Scope Of...Generally, the scope of works of this tender shall include but not limited to the ... pipe to the header. ... Work together with the supplier to

CT1501B004 PROPOSED TENDER FOR THE REPLACEMENT OF CHILLER SYSTEM AT SATS AFT 2, 95 AIRPORT CARGO ROAD S819461, AND AFT 3, 105 AIRPORT CARGO ROAD S819462

Scope of Works TS-SW-1

PART V

SCOPE OF WORK



SCOPE OF WORK

1. General

1.1. The site for the replacement of the air-conditioning systems are at SATS AFT 2, 95 Airport Cargo Road S819461 and AFT 3, 105 Airport Cargo Road S819462.

1.2. SAS (The Owner) shall not be bound to accept the lowest or any tender. The Owner reserves the right to accept the whole or part of the tender.

1.3. Generally, the scope of works of this tender shall include but not limited to the following principal items:

PART 1 – Chiller Plant Room:

AFT 2 Plant

I. Decommissioning, dismantle and disposal of 2 sets of cooling tower with associated pipe and accessories including but not limited to stop valves.

II. Decommissioning, dismantle and disposal of 2 nos existing chiller with associated pipe and accessories including but not limited to balancing valves and stop valves.

III. Decommissioning, dismantle and disposal of 3 sets of chilled water pump and 3 sets of condenser water pump with associated pipe and accessories including but not limited to stop valves.

IV. Decommissioning, dismantle and disposal of 1 no chilled water expansion tank with associated pipe and accessories.

V. Decommissioning, dismantle and disposal of 1 no existing aircon electrical panel and associated works.

AFT 3 Plant

VI. Decommissioning, dismantle and disposal of 2 sets of cooling tower with associated pipe and accessories including stop valves.

VII. Supply, install, testing and commissioning of 1 cooling tower set with minimum capacity of 700HRT consisted of 4 cells and each cell shall be separated with internal partition and separate basins. The cooling tower installation work shall include necessary pipework, gauges, joints, modification of makeup pipe, spring isolators, additional support, new I-beam, installation of new motorized valves, water level sensors, walkway & safety hand rail for maintenance, access cat ladders from floor, water proofing work and new electrical panel including individual VFD for each cell to modulate the fan speed with redundant electro mechanical starter as back up. The electrical panel shall have selector switch to select between auto & manual mode, and VFD & electro mechanical starter.



VIII. Decommissioning, dismantle and disposal of 2 nos existing chiller with associated pipe and accessories including balancing valves and stop valves.

IX. Supply, install, testing and commissioning 2 nos new chiller with associated pipework and accessories including motorized valves. Minimum chiller capacity shall be 250RT matching with building load profile with minimum load of 20% using single/multi compressor (VFD), flooded type evaporator complete with thermal insulation (armaflex insulation for evaporator and condenser). The scope of work shall include but not limited to chilled water pipes with mechanical joint, reducer, stainless steel flexible joint, pressure gauge, temperature gauge, differential pressure switches, motorized valves, butterfly valves, joints, brackets, spring isolators, drain pipe, plinth extension, etc, as shown/stated on the specification drawings and schedule of technical particulars. Reconnect the chilled water supply pipe to the header.

X. Decommissioning, dismantle and disposal of 3 sets of chilled water pump and 3 sets of condenser water pump with associated pipe and accessories including stop valves.

XI. Supply, install, testing and commissioning 2 sets of chilled water pump with associate pipe & accessories, check valve, strainer, suction diffuser, insulation (for CHWP) and VFD.

XII. Supply, install, testing and commissioning 2 sets of condenser water pumps with associate pipe & accessories, check valve, strainer, suction diffuser and VFD.

XIII. Decommissioning, dismantle and disposal of 1 set of existing chilled water header and 1 set of existing condenser water header.

XIV. Supply and install 1 set of new chilled water common header for the chillers to operate parallel pumping system.

XV. Supply and install 1 set of new condenser water common header for the chillers to operate parallel pumping system.

XVI. Supply and install 1 set of chilled water link pipe between AFT 3 and AFT 2 plants.

XVII. To provide freezing / hot tapping, if necessary, to ensure no disruption of normal operation during the works.

XVIII. Supply, delivery, install, and testing commissioning a new AC switch board to accommodate new chillers, pumps and cooling tower. The switch board shall have selector switch to select between auto & manual mode, and select pump starter between VFD & electro mechanical starter (A/T). The scope of work shall include supply and install new power cable and control cable for the 2 new chillers, 4 sets of chilled water & condenser water pumps and 1 cooling tower. A junction box shall be provided for connection with the existing incoming cable from the main switchboard if required. The new switchboard design shall be endorsed by a qualified PE.

XIX. Supply, install, testing and commissioning 1 new set of chemical water treatment system for cooling tower.



XX. Supply, install, testing and commissioning of automatic tube cleaning system (brush type) for the 2 new chillers including all necessary modification to the pipeworks to accommodate the operation of the system. Also responsible for open-up the chiller water box for inspecting the conditions of condenser tubes before the end of Defect Liability Period.

Note : The installation of the new auto tube cleaning system shall not compromise the performance of the chiller system.

XXI. Supply, installation, testing and commissioning 1 set of refrigerant leak detection system in chiller plant room as per ASHRAE Standard 15-2007 including control panels and associated wiring as well as all the cable trunking, conduit, brackets, etc.

XXII. To meet the targeted plantroom system efficiency of 0.65 kW/RT or better. The contractor shall verify the chiller plant performance upon testing and commissioning and before handover at end of Defect Liability Period.

XXIII. All items of accessories, piping, electrical, wiring and labor whether specified in details or not but in the opinion of the Owner/Consulting Engineer are usual or necessary for the satisfactory completion of the installation of Air-Conditioning Chillers and associated equipment shall form part of the Scope of Works.

PART 2 – CPA (CHILLER PLANT AUTOMATION):

i. The Tenderer shall ensure a successful implementation and commissioning of the Central Plant Automation herein referred to CPA. The scope shall include but not limited to,

I. Supply, delivery, installation of 8 nos flow meters, testing and commissioning of flow meter for chilled water and condenser water loop for all chillers and headers. Full bore magnetic type shall be used with accuracy of at least 1%. Ensure the installation locations of the meters are according to the manufacturer recommendation.

II. Supply, delivery, installation of 16 nos temperature sensors (Thermistor) complete with thermowell at the designated points. The thermowell should have an open tip with test plug for sensor insertion. The sensors shall be calibrated with 3 points calibration and shall meet minimum accuracy of ± 0.05 deg C at 0 deg C. Sensors must be in direct contact with fluid flow. Sensor must be calibrated by SAC-SingLas accredited lab. Each calibration cert should provide the three constants for the “Steinhart-Hart Equation”.

III. Supply, delivery, installation of 4 nos pressure transducer at the designated points to determine system pressure and to control pumps modulation thru VFD.

IV. Supply, delivery, and installation of 2 test points with stainless steel ball valve including test plug beside the new temperature sensors shall be provided for site verification. (2 test points per temperature sensor)

V. Supply, delivery, installation and commissioning of 11 nos class 0.5 power meter with ±0.5% accuracy current transformers to provide total



plantroom absorb power and consumption. The power meter shall be integrated in the new AC switchboard and have the capability to be linked to CPA thru HLI (High Level Interface). All plant room equipments and incoming power should be monitored with power meter.

VI. Work together with the supplier to ensure the supplied sensors can meet the total uncertainty of measurement not more than 5%. And CPA shall be able to demonstrate heat balance of the plant with tolerance of not more than ±5% at 80% of the operating period.

VII. CPA shall be able to communicate with existing AHU controllers through the high level interface.

VIII. Supply and installation of the new Chiller Plant Automation system (CPA) to comply with the latest NEA requirements for the new chiller system. The new system shall be capable of trend logging to minute to minute intervals of the critical operating parameters of the new chiller system. It shall be complete with software program, licenses, standard graphics display, remote monitor features and printer for all chiller plant automation system services with complete configuration.

The works shall include all necessary works to comply with the latest NEA requirements not limited to the following:

1 lot of DDC controllers with data acquisition capability at 1-min intervals and minimum resolution of 22 bit

Measurement and verification system with remote capabilities

Heat balance substantiating computation algorithm

Capable of keying the calibrated temperature sensor constants for the Steinhart-Hart Equation.

Auto generation of monthly Measurement & verification (M&V) report

Note : Please refer to the attached CPA point schedule for the new system which shall be complied with.

ii. All items of accessories, piping, electrical, wiring and labor whether specified in details or not but in the opinion of the Owner/Consulting Engineer are usual or necessary for the satisfactory completion of the installation of Air-Conditioning Chillers and associated equipment shall form part of the Scope of Works.

iii. All the power cable for new equipments from AC switchboard panel to each of the equipment (chiller, pump, cooling tower) shall use new cable.

iv. All VFD for indoor use shall be IP55 and outdoor use shall be IP65.

v. To provide complete service of SAS in House LEW (Licensed Electrical

Workers) as required by the Local Authorities to take complete charge of chiller plant electrical switchboard upgrading works and all cost connected herewith including fees payable to the Authorities, Power grid and Client.



vi. To provide complete service of a Structural Professional Engineer registered with Singapore PE Board to calculate and check proposed equipment loading imposed on existing structure including delivery access & temporary storage area and recommend reinforcement measures if necessary and take complete charge of all cost connected herewith including fees payable to the Authorities, and Client.

vii. The contractor shall engage qualified person to verify with calculations the sizing of pipes and pump head etc. using the actual pumps, lengths and bends of pipes etc. after the equipment final selection. The contractor shall provide pumps with the increased pump head if necessary as shown by the calculations, at no additional cost to the client.

viii. All the work shall not affect the operation of the plant and shall provide an adequate redundancy for back up in the event of emergency.

ix. Any query between the requirements of this section and other relevant documents shall be referred to the OWNER/Consulting Engineer for clarification.

x. Compliance with the provision of this Specification does not relieve the Tenderer of the responsibility to supply Air-Conditioning equipment of proper design and suitable for operation as intended.

xi. The works to be executed under this Contract shall be in compliance with all the latest regulations, by-laws and accepted Code of Practice.

The following is a non-exhaustive list of some of the regulations, by-laws and accepted Code of Practice:

Ministry of Manpower;

The electrical Act and the EMA Regulations;

Fire Code 2007 Master Plan;

Environmental Health Department. Ministry of Environment;

Building and Construction Authority;

The latest edition of Singapore Standard CP5, Code of Practice for Electrical Installation;

The latest edition of Singapore Standard SS.530: 2006, Code of Practice for Energy efficiency standard for building services and equipment;

The latest edition of Singapore Standard Code SS.551:2009, Code of practice for earthing;

The latest edition of Singapore Standard SS.553:2009, Code of Practice for Air-conditioning and mechanical ventilation in buildings;

The latest edition of Singapore Standard SS.554:2009, Code of Practice for Indoor air quality for air-conditioned buildings;

The latest edition of Singapore Standard SS.538:2008, Code of Practice for Maintenance of Electrical equipment of electrical installations;

The latest edition of Singapore Standard SS.591.2013, Code of Practice for Long Term Measurement of Central Chilled Water System Energy Efficiency

The latest edition of Singapore Standard CP 48: 2005 Code of Practice for Water Services;

http://www.singaporestandardseshop.sg/product/productView.aspx?id=63e5a71e-b74b-4f6f-99df-df855df9c5da

http://www.singaporestandardseshop.sg/product/productView.aspx?id=63e5a71e-b74b-4f6f-99df-df855df9c5da



The latest edition of Code of Practice for The control of Legionella Bacteria in cooling towers;

BCA Code for Environmental Sustainability Of Buildings, 3rd Edition;

BCA Green Building Design Guide – Air-conditioned Building;

BCA Green Mark Criteria for Non-Residential Existing Buildings Version NREB 3.0

ASHRAE Standard 15: 2007 – Safety Code for Mechanical Refrigeration;

ASHRAE Guideline 22: Instrumentation for Monitoring Central Chilled Water Plant Efficiency.

ASHRAE Standard 90.1: 2007 – Energy Standard for Building Except Low-Rise Residential Buildings;

ASHRAE Standard 111: 2009 – Measurement, testing, Adjusting, and Balancing of Building HVAC Systems;

ARI Standard 550/590: 2003 – Performance Rating of water Chilling packages Using the vapor Compression Cycle;

All other Authorities having jurisdiction over the installation.

xii. The works include shall not limited to those in this specification and the drawings as per following description and/or any unspecified or non-indicated works which are necessary in the course of installation for a complete and satisfactory system.

2 Notice to Tenderers

i. All the equipment offered shall comply to NEA requirement and of the most energy efficient type.

ii. It shall be the tendererer’s responsibility to ensure selected equipments are able to achieve the overall weighted average chiller plant system efficiency of 0.65kW/RT or less during operating hour.

iii. The owner or Consulting Engineer reserves the right to eliminate any or part of the above items from the tender even if such items have been tendered for.

iv. The tenderer is to note that the general description of works as stated above is only guidance for the tenderer and any error or omission shall not constitute a ground for claim. The onus for investigating and ensuring the actual extent and nature of the works comprised in this tender prior to the submission of this tender, is solely with the tenderer. Any doubts as to the actual extent or nature or works shall be clarified with the Consulting Engineer before the submission of tenders as no claims arising out of lack clarity or availability of information will be entertained.

v. The tenderer shall be aware the nature of the building and familiar himself with the operation of the building. The tenderer is to note that SAS AFT 2 & 3 is a live building; all noisy work shall not be carried out during the day or weekend. And in no circumstance, the upgrading work shall affect the normal daily operation of the building. Any major shut-down need be coordinated closely with maintenance people and approved by owner or its representative.

vi. Every component of the control equipment shall be able to work in tropical climate and be complete with mountings, guards and associated accessories.



All new equipment and control panel shall be installed at conducive location for easy maintenance and being approved by client /consultant before installation.

vii. All unwanted and redundant equipment, piping, conduit, control panel, etc., shall be dismantled and dispose off site, and all the opening shall be proper sealed off with fire stop material of the same rating of the wall or slab.

viii. The work also includes comprehensive maintenance and service upon installation of new equipment / system until the certification of practical completion. All parts and consumables as per manufacturer’s recommendation shall be included.

ix. The work also include 12 months DLP (Defect Liability Period) service upon Practical Completion of all newly installed equipment and components which includes monthly scheduled preventive maintenance and yearly annual shutdown maintenance (excluding tube cleaning on water cooled chillers). All parts and consumables as per manufacturer’s recommendation shall be included.

x. All the other works not specifically mentioned above but are stipulated or shown elsewhere in the specification and drawings.

xi. All other works and services contingently or eventually necessary for the Works whether specifically mentioned in the specification and drawings or inferred herein or not.

xii. Supply of complete operation and maintenance manuals including as-built drawings in hard and soft copies.

3 Certificates, Permits & Fees

i. The tenderer shall apply and obtain all necessary certificates and approval from the governing Authorities if required for the work done and shall lodge same with the Consulting Engineer. The tenderer shall also obtain and complete all permits and notices required by the governing Authorities and shall obtain consents necessary for the various works to be executed. The tenderer shall pay all fees in connection therewith.

4 Shop Drawings & As-Built Drawings

i. The tenderer shall submit, no later than Fourteen (14) days after the award of the tender, complete shop drawings for all the installations and works under this tender. These shop drawings shall be submitted for prior approval before any installation may be commenced.

ii. The shop drawings shall be complete and show all working details. Details shall be shown not smaller than the following scales:-

Chiller Plant (Chillers & Pumps) & CT’s 1:100

Chiller Plant room single line and as built 1:50

Chiller Plant room/Electrical Power distribution 1:50

Floor Plans under this project 1:100



iii. All drawings shall be of size ISO A1.

iv. Two sets of the shop drawings shall be submitted for vetting by the consulting engineers. The drawings shall be fully coloured as follows for ease of checking :-

RED Proposed works to be carried out or installed

YELLOW Installations to be deleted or removed

BLUE Existing works to be retained

v. After vetting and commented upon, one set of the drawings will be returned to the tenderer for his information. This drawing shall be known as the commented drawings. Should drawing changes be required or additional information be required, the tenderer shall submit the new drawings together with any previous commented drawings to the consulting engineers. Drawing submissions without the attachment of the commented drawings will be rejected.

vi. Upon completion of the Works, the tenderer shall submit to the consulting engineer, three (3) sets of As-built drawings incorporating final details of the installation as constructed. The drawings shall be vetted by the consulting engineer or his representatives for accuracy and completeness. On approval, the tenderer will submit three (3) sets of drawings endorsed by consulting engineer for distribution to various parties as final record. A complete set of the approved as-built computer aided design drawings in AutoCAD format (release 2005 or later) and pdf shall also be submitted on CD or DVD.

5 Guarantee of New Chiller Plant Efficiency

i. Tenders are to guarantee the plant average efficiency of 0.65 kW/RT or better, with chilled water supply temperature not more than 8

oC, at office hours

(Monday to Sunday 8:00am to 6:00pm).

The chiller plant efficiency is defined by following formula:

.

ii. Upon completion of chiller plant upgrading, the contractor shall log at 1 minute interval of the following as a minimum:

Chilled water flow rate, supply and return temperatures at main pipe.

Total Power incoming to main air-con switchboard and individual chiller,

pump and cooling tower power consumption;

Condenser water flow rate, supply and return temperatures at main pipe;

Software calculation of chiller plant tonnage, plant system and chiller

efficiency, Cooling Tower Heat Rejection Tonnage;

Heat Balance (Sum of Cooling Load & Heat Compression from Chiller),

heat balance of the plant with tolerance of not more than ± 5% at 80% of

the operating period.



iii. Two week sample data (at 1 min interval) will be collected for analysis and verify chiller plant performance upon completion.

iv. If the new system weighted average efficiency ( = Sum of Total Power

consumption / Sum of Chiller plant Tonnage ) fails to meet the guaranteed

figure (declared in the Form of Tender) by the end of DLP after all necessary

fine-tuning and adjustment, the contractor shall be liable to pay a penalty to

compensate the additional electricity cost resulting from poorer Chiller plant

efficiency for shortfall in Chiller Plant efficiency from the guaranteed efficiency

declared in the Form of Tender. The penalty for shortfall in Chiller Plant

Efficiency shall be:

Penalty for every 0.01 ikW/RT or part thereof = 0.01 ikW/RT x baseline cooling

demand (RTh/yr) x weighted average tariff for the year x 10 years

Where,

Baseline cooling demand = 925,466 RTh/yr

Weighted average tariff = ∑(Tariff Rate)n / 12

v. The performance bond of the contract value will only be released after

deduction of penalty sum, if any, upon verification of plant performance by

owner / Consulting Engineers during the testing and commission of the new

plant system and at end of Defect Liability Period.

vi. For avoidance of doubt, the penalty that the Contractor shall be liable for any

shortfall in Chiller System efficiency stated in the Form of Tender shall be

calculated as follows:-

Assuming Contract Sum = $1,500,000

Average Cooling load = 230 RT

Guaranteed Efficiency : 0.65 kW/RT

Achieved Efficiency at end of DLP : 0.70 kW/RT

Assuming Tariff for the particular year is :

Period Jan – Mar Apr – Jun Jul – Sep Oct – Dec

Tariff ($/kWh) $0.20 $0.24 $0.23 $0.22

Weighted Average Tariff = ($0.20 x 3 + $0.24 x 3 + $0.23 x 3 + $0.22 x 3)/12

= $0.2225/kWh

Penalty Contractor is liable to,

= (0.70 – 0.65) kW/RT x 925,466 RTh x

$0.2225/kWh x 10 years

= $102,958



i. For the avoidance of doubt, the remedy set out in (iv) shall be the Company’s

sole remedy against the Contractor in respect of any loss suffered or incurred

as a result of the shortfall in the Chiller System efficiency.



6 Building Load Profile



Documents

SCOPE OF WORK - SATS Ltd Scope Of...Generally, the scope of works of this tender shall include but not limited to the ... pipe to the header. ... Work together with the supplier to