Contract: SID EE 35-2015/2016
Scope of work
- SCOPE OF WORK
1.1Description of the SERVICE
The purpose of this tender is to appoint a service providerto chemically clean boiler tubes at Rooiwal Power Station as and when required for a three (3) year period.1.2Procurement Strategy
1.2.1Programme for delivery
The successful tenderer shall clean boiler tubes using chemicals as per official orders signed by the Chief Financial Officer: Finance Department, and in such quantities as may be required periodically by the City of Tshwane.The relevant order number(s) must appear on all invoices and delivery notes.
The expected completion date is 31 days from receipt of official order.
1.3ABBREVIATIONS
CBD – Central Business DistrictSCM - Supply Chain Management
SLA – Service Level Agreement
OHS - Occupational Health and Safety
VAT – Value Added Tax
MCR – Maximum Continuous Rating
km – Kilometre
MW – Mega Watts
°C - degree Celsius
Kg/h – kilogram per hour
mm – millimetres
BS – British Standard
HCL – Hydrochloric Acid
HP – High Pressure
Max. - maximum
1.4EVALUATION CRITERIA
The bid will be evaluated in Three stages as follows:a)Phase 1: Admin compliance
b)Phase 2: Technical compliance of the document,
c)Phase 3: 90/ 10-point system as prescribed in Preferential Procurement Policy Framework, Act of 2000
1.Phase 1
The tenderers must submit the required returnable documents as required by the City of Tshwane’s Supply Chain Management requirements.
2.Phase 2
The tenderer’s bids will evaluated based on the compliance of the following:
(a)Certified copies of type test certificates from an accredited
testing facility.
(b)Completion of Schedule of tenderer’s experience” (Annexure A)
(c)Submission of Letters of previous appointment relating to the scope of work.(To be submitted with the Tender Documents)
(d)Completion of Annexure B- SCHEDULE OF PARTICULARS
(e)Submission of Product brochure/ Material safety data sheet.
3. Phase 3
The 90/10-point system as prescribed in Preferential Procurement Act is as follows:
(a)Price 90 points
(b)BBBEE 10 points
1.5CONSTRAINTS
1. LAWS AND REGULATIONSThe tenderer shall, in all respect of all matters arising in the fulfilment of the contract, conform at his/her own expense to all laws, regulations, by laws and requirements of local, provincial, national and other authorities which are applicable to the contract works.
The tenderer shall in respect of the site of the contract works appoint, in writing, a competent person to meet the requirements of the Occupational health and safety Act, ACT NO. 85 of 1993, as amended. Copies of the said appointment shall be lodged with the municipality before commencement of work on site
This shall be enforced through the SLA which will be signed by the City Manager.
2. CO-ORDINATION WITH WORK OF OTHERS
The Rooiwal maintenance team will co-ordinate the execution of the contractors work with the work of other contractors on site. The contractor shall co-operate with and shall not delay, impede or otherwise impair the work of others. The Rooiwal boiler technical team does not guarantee the continuous, uninterrupted access to work area but will provide such access as good maintenance and safety practice will allow in the circumstances.
3. APPROVAL AND REJECTION OF WORKMEN
The contractor shall employ competent personnel for the execution of the works. People that have been dismissed from being employed on the contract due to misconduct or any other reason will not be re-employed again by the contractor without written permission from the City of Tshwane.
4. CLEANING OF WORK SITE
During the period of the contract work execution, the contractor shall keep the site clean and tidy in accordance with the Municipality’s requirements. When the whole of the contract works is completed the contractor shall at his own expense remove all debris and temporary erections and shall ensure that the site of the contract works is cleared and made safe.
1.6Particulars to be included on the Supplier’s Invoice
After completion of delivery, the service provider shall invoice the City of Tshwane and the City of Tshwane will only pay after receiving invoice of the work completed after being certified by Rooiwal maintenance team.The service provider must include in his invoices the following
- Contract number
- Contract description
- VAT number
- Vendor number
1.7Delivery of goods and SERVICES instructions
1. Delivery is to be made to the Rooiwal Power Station, situated approximately 23km North of Church Square of Pretoria CBD, on the old Warmbaths road (R101 road) towards Hammanskraal.2. The briefing session is compulsory; and the venue for the session at Rooiwal Power Station (Board room 111). Contractors are reminded to bring their own safety boots, safety helmets and ear protection to the meeting.
3. All correspondence shall be in writing.
1.8Applicable national and international standards
The latest revision of the following standards shall apply:1. Occupational health and Safety act, 1993 (Act No.85 Of 1993)
2. And any standards or legislations that are related to the execution of the
work as determined by relevant authorities
1.9Particular / generic specifications
- BACKGROUND
Each boiler consists of a furnace, economiser, evaporator, steam drum, super-heater, down comers, boiler tubes, etc. The boiler tubes accumulate sludge and other deposits which require chemical cleaning to maintain the temperature and boiler efficiency. The chemical cleaning processes used shall remove all deposited and accumulated iron and copper oxides, metallic copper and waterside scale, and deposits from the evaporator and economiser sections of the boiler in several cleaning stages.
All accumulated, loose or dislodged sludge from the boiler tube cleaning process shall be removed by adequate circulation and flushing velocities to prevent tube blockage at a later stage. Headers shall be opened and mechanically cleaned. Proof shall be given of the velocity of flow in the various sections of the boiler while the cleaning is performed.
As the boilers have previously been treated by chemical cleaning, a number of permanent modifications, including bolt on fittings and connections are available. Preference shall be given to methods which do not require alterations to the existing provisions and equipment.
Due to the nature of work the city of Tshwane intends to appoint only one service provider. The service provider will be required to work under the supervision of Rooiwal maintenance team.
2. SCOPE OF WORK
This tender provides for the chemical cleaning of boiler tubes at Rooiwal Power Station as and when required for a three (3) year period.
This specification provides for the removal of iron oxides, copper oxides, metallic copper and all waterside scale, and deposits from the evaporator and economiser sections of the boiler by chemical means.
It is intended to individually chemically clean the water side surfaces of all 5 boilers, sequentially, at different intervals.
TECHNICAL DETAILS
2.1BOILER DATA
2.1.1Designer and manufacturer: Yarrow and Company Limited.
2.1.2Type: 60 MW, PF fired radiant, natural circulation.
2.1.3Maximum continuous steam rating: 250 000kg/h.
2.1.4Number of stages of superheating: Two stages.
2.1.5Final superheated steam temperature: 490°C.
2.1.6Final superheated steam pressure: 6.5MPa.
2.1.7Steaming hours since previous chemical cleaning: ± 55 000 hours.
2.1.8Weight of water in drum (full): 17 500kg.
2.1.9Weight of water in furnace: 50 000kg.
2.1.10Weight of water in economiser: 8 813kg.
2.1.11Steam drum working pressure: 7.10MPa at MCR.
2.1.12Economiser working pressure: 7.28MPa at MCR.
2.1.13Furnace surface area wetted: 2 681m2.
2.1.14Economiser surface area wetted: 1 144m2.
2.1.15Diameter of furnace tubes: 65.4mm.
2.1.16 Diameter of economiser tubes: 38.2mm.
2.2MATERIALS OF CONSTRUCTION
2.2.1Boiler drum: Mild steel; 478MPa; Tensile strength.
2.2.2Furnace tubes: BS3059 Part 2 360 (hot finished, seamless).
2.2.3Economiser tubes: BS3059 Part 2 360 (hot finished, seamless).
- PROCEDURE FOR CHEMICAL CLEANING
The super-heater would be protected from any chemical ingress by filling and water-wedging, with frequent inter-stage back-flushing into the steam drum.
Restrictors would also be installed in the main down-comers to prevent preferential flow.
STEPS OF CLEANING PROCESS
The cleaning process shall comprise of the following stages:
3.1Installation of Contractor's temporary pipe-work, pumps and chemical
solution or circulation tanks, as well as auto-circulation gas lines and
cylinders required.
3.2 Hydraulic tests on all temporary process pipe-work using the
Contractor's pumps to ensure safe operating conditions before
Commencement of the chemical injection process.
3.3 Copper and copper oxides removal
3.3.1Initial copper removal using alkaline oxidising chemicals.
Preference shall be given to the following non-volatile oxidising agents:
1% Ammonia solution
0.5% Ammonium Bicarbonate
0.3% Ammonium Persulphate At a temperature 40-45°C
3.3.2Drain and water Flush to remove all alkaline traces
3.4 Iron and iron oxides removal
3.4.1Iron removal using acidic chemicals.
Preference shall be given to the following acidic chemicals:
5% HCl acid
0.2% Ammonium Bifluoride
0.2% Inhibitor
At a temperature 60-65°C
3.4.2. Drain and water flush to remove all acidic traces.
3.4.3 HP water wash to remove sludge deposits from headers and drum.
3.5Second copper removal similar to 3.3, but using half of the chemicals
concentrations used in 3.3.
3.6Drain and water Flush to remove all alkaline traces
3.7Polishing steps for firstly iron and then copper removal. These steps
shall also provide for a final passivation of the surfaces, i.e.
reinstatement of a protective magnetite layer.
Preference shall be given to the following chemicals
0.5% Citric acid
1%Ammonia solution
0.2% Hydrogen peroxide
At ambient temperature - 35°C max.
3.8Draining and flushing.
3.9Flushing and cleaning of headers.
3.10Inspection of the boiler for acceptance of the cleaning process by the Rooiwal boiler maintenance team.
3.11Removal of temporary pipe-work and equipment after successful cleaning.
3.12A site report stating all occurrences during the cleaning process, chemical analysis of the cleaning solutions and a calculation of the mass of copper and iron removed shall be submitted.
3.13The Tenderer is at liberty to recommend additional steps or a change in the order of
the steps to suit his recommended process.
4.INSPECTION AND METHODOLOGY
4.1The boiler shall be inspected after completion of the chemical cleaning
process to establish whether it has achieved the desired results; that is
the removal of all metallic copper, copper and iron oxides and waterside
scale, and deposits from the boiler and whether a passive film has been
formed on the metal surfaces.
4.2.The City of Tshwane can use visual inspection at its disposal during the inspection to reach a decision or consider any expert's advice.
4.3Should such examination indicate that the cleaning process has proved
unsuccessful; the cleaning process or a modification thereof shall be
repeated at no extra cost to the City of Tshwane.
5.AVAILABLE PROVISIONS
The following provisions shall be available to the successful tenderer
free of charge:
5.1A three phase, 415V, 50Hz and/or a single phase, 240V, 50Hz power
supply.
5.2Disposal point for effluent.
5.3Town water and demineralised water within the capacity of the water
treatment plant, on condition that there will be no interference with
normal power station operation.
5.4Scaffolding to access down comers.
5.5Air for auto-circulation if required, but not nitrogen gas.
6. TRANSPORTATION OF DANGEROUS GOODS REGULATIONS
The Contractor shall comply with the requirements with respect to the
Transportation of Dangerous Goods in or on a vehicle on a public road,
as determined in the Standard Specification and Codes of Practice
referred to in Section 273A of the Regulations (National Road Traffic Act,
Section V111, Act 93 of 1996, as amended).
For the duration of the contract works, the Contractor shall be registered
with the Department of Transport for the purpose of transporting dangerous goods by road.
The driver shall be in possession of a professional driving permit issued in terms of Section 115(1)(f) of the Regulations, as amended, and who is not disqualified in terms of Section 117 of the Regulations, as amended.
The Contractor shall ensure that the dangerous goods presented for transportation will be packed in packaging that has been approved and marked in the manner contemplated in Code of Practice SABS 0233 “Intermediate Bulk Containers for Dangerous Substances”’ as amended, and Code of Practice SABS 0299 “Packaging of Dangerous Goods for Road and Rail Transportation in South Africa”, as amended.
7.OFFLOADING
The Contractor must inspect the off-loading site to ensure
compliance with the Occupational Health and Safety (OHS) and Road Traffic (RT) Acts, as amended, and if necessary make recommendations.
The Contractor is to provide staff training on site for OHS and RT Acts, as amended, competent persons.
The Contractor shall supply labour for the off-loading of the product.
The Contractor must have a 24 hour Hazardous Chemical Emergency Response facility in place. Proof must be submitted with the tender.
8DATE OF CLEANING
8.1Commencement of the chemical cleaning sequence is scheduled to start once the official order is supplied, but the City of Tshwane reserves the right to change the dates in the event of unforeseen inopportune circumstances.
8.2The Contractor shall be required to commence the chemical cleaning
of the first boiler within 14 days of receipt of the Council's confirmation
of tender acceptance, and thereafter, repeat the process, to
individually chemically clean the balance of 4 boilers sequentially, at
intervals and dates to be confirmed by the Council, similarly
commencing chemical cleaning within 14 days of given notice.
8.3The total time required for the chemical cleaning of each boiler,
including the installation and removal of equipment, shall not exceed
30 working days
9. Service Level Agreement
It is expected that the successful bidder to enter in a service level agreement (SLA) with the City of Tshwane with regards to the deliverables and performance of this contract. The following paragraphs will form part of the SLA.
Paragraph Two (2), Three (3), Four (4), Six (6), Seven (7) and Eight (8) will be enforced through SLA. The City of Tshwane reserve the right to add more information to SLA that will assist performance and deliverables.
2Certification by recognised bodies
It is a requirement of the contract that the Manufacturer maintains an effective documented system for the control of product quality.3hEALTH AND SAFETY SPECIFICATION
MINIMUM OCCUPATIONAL HEALTH & SAFETY REQUIREMENTS
I in my capacity as
representing(contractor)
hereby agree in terms of Section 37(2) of the Occupational Health and Safety Act 1993 (Act 85 of 1993) that I am an employer in own right and hereby take upon myself the duty to ensure that myself and my employees will adhere to the requirements as set out below and all other requirements as set out in the Occupational Health and Safety Act 1993 and its regulations.
- INTRODUCTION
1.1.The Municipality requires a high standard of safe work performance from all employees and expects that the standard be maintained by the contractor within the Municipality’s jurisdictional area or on its premises.
1.2.Irrespective of human considerations, the maintaining of these health and safety rules shall be the execution of the prescribed legal requirements. These rules are not to hinder the contractor in rendering services or indemnify the contractor from any legal responsibility to ensure healthy and safe work circumstances.
1.3.The Municipality shall assist the contractor in any practical considerations to accommodate the healthy and safe execution of work and therefore require co-operation in the execution of these safety rules
- LOCK OUT PROCEDURE
2.1.When power or air driven machines or equipment, electrical apparatus or pipe lines are examined, repaired, adjusted, cleaned, lubricated or serviced in any other way than normal servicing, then all isolating switches, -levers, valves or appliances must be put in the “off” or “closed” position and locked.
2.2.Should more than one team work on a machine, then each person in control of a team, must put a separate lock on the switch, lever, valve or appliance.
- CRANES, VEHICLES AND HOISTING
3.1.For each crane or hoisting equipment used, the contractor must submit a valid and recent test certificate or other form of the last examination of the machine or equipment, to the Municipality.
3.2.Only trained personnel with written permission and where determined by Law, with a valid driver’s license, may be allowed to operate any electrical diesel or petrol driver overhead crane, hydraulic or electrical hoisting equipment, self- driven forklift, tractor or any other crane
or vehicle. No employee of the contractor may perform any overhead work or work on an overhead crane or hoisting equipment or work near cranes or crane rail, before:
- An agreement was concluded with the Municipality.
- Approval has been obtained from the Municipality to perform the work.
- All applicable danger – and warning symbolic signs are put into position, or exemption, if applied for, is in operation
- MACHINE VALANCES, PROTECTION AND FENCING
4.1.No machine valances, protection or fencing may be removed from machines, manholes, etc without the written permission of Municipality if applicable exemption procedures were not appropriated.
- SCAFFOLD, LADDERS, TOOLS AND EQUIPMENT
5.1.No equipment or appliance belonging to Municipality may be used without written permission from the Municipality.
5.2.Unless prior arranged, contractors must bring sufficient tools and equipment to the site to finish the contract, including offices and storerooms. The mentioned equipment remains the responsibility of the contractor with respect to loss, damage and theft.
- EXCAVATIONS
6.1Before any excavations commence, the contractor must obtain information with regard to all existing services. The Municipality does not guarantee the accurateness of the information supplied.
6.2All excavations and obstructions in floor, tar and dirt surfaces must be fenced effectively and safeguarded between sundown and sunup with a sufficient amount of red/yellow warning lights and symbolic signs.
6.3The surrounding area must be kept clean, safe and tidy during excavation. Excess material may not obstruct unnecessarily