UNDP/PAPP
Palestine Construction of the Khan YounisWaste Water Treatment Plant
Volume 2 – Part 5 – Technical Specifications – Mechanical & Instrumentation Works
Palestine
Construction of the Khan Younis
Waste Water Treatment Plant
Volume 2 – Technical Specifications
Part 5 – Mechanical and Instrumentation Works
Contents
Section 01020 BASIC MECHANICAL REQUIREMENTS
Section 01030 BASIC ELECTRICAL REQUIREMENTS
Section 11210 SCRAPER AND SUCTION BRIDGES
Section 11220: VERTICAL SHAFT MIXERS
Section 11221 SUBMERSIBLE HORIZONTAL SHAFT MIXERS
Section 11285: UV DISINFECTION
Section 13220 FILTER UNDERDRAINS AND MEDIA
Section 13241 Air blowers
Section 13242 AIR DIFFUSION SYSTEMS
Section 14100 PIPES AND FITTINGS
Section 03611 CONCRETE PIPES
Section 14150 VALVES, GATES & APPURTENANCES
Section 14300 MISCELLANEOUS PUMPS
Section 15415 Fine screening equipment
Section 15425 GRITCLASSIFIERS
Section 15550 VENTILATION
Section 15570 BIOLOGICAL NATURAL SUBSTRATUM ODOUR TREATMENT
Section 16000 CONVEYING SYSTEMS
Section 17 200 STOP LOGS
Section 18100 INSTRUMENTATION
SOGREAH Consultants/Universal Group N° 1310076 - October 18 Volume 2 – Part 5 - Page 1
UNDP/PAPP
Palestine Construction of the Khan YounisWaste Water Treatment Plant
Volume 2 – Part 5 – Technical Specifications – Mechanical & Instrumentation Works
Section 01020
BASIC MECHANICAL REQUIREMENTS
1.General
1.1.Work included
This section of the specifications covers the general requirements applicable to all mechanical equipment to be supplied, unless different requirements are specified in the subsequent sections.
In case of conflict between the requirements of this general specification and those of the specific equipment specifications, the latter shall have precedence.
1.2.Quality assurance
1.2.1.General
The equipment shall be manufactured in accordance with established practice. All the components shall be finished as required by their importance, position and destination. The manufacture shall be sound, without any faults likely to impair their ability to fulfil their purpose:
1.All equipment shall be designed in compliance with up-to-date practice;
2.Equipment design shall take into account control and maintenance operations as well as operating incidents;
3.The general aesthetic appearance shall be studied and shall blend in with the overall architecture of the structures.
1.2.2.Materials
1.2.2.1.General
Materials shall be new and of first class quality.
Rolled and cast steel shall be of good quality and free from blow or shrinkage holes, porosity, cracks or other defects.
Cast iron is not acceptable for any tap, valve bodies or components subject to internal pressure.
The Contractor shall indicate in the calculation notes the quality of the materials with reference to International (ISO) or American (ASTM,..) or European (DIN or BS or NF,..) or Japanese (JIS) or equivalent standards, and their mechanical and chemical properties. Such information shall be given for all materials used in the construction of the main items of equipment before procurement commences.
Materials shall comply with the list below or be similar according to other acceptable standards:
1.2.2.2.Main types of materials
European standards or equivalent as below:
- Structural steel:...... EN 10025
...... EN 10137
- Non alloy high strength steel:...... EN 10083
- Low alloy high strength steel:...... EN 10083
- Corrosion resisting steel:...... EN 10088
- Iron casting:...... EN 1561
- Alloy steel casting:...... A 32054
- Steel bolts and nuts: ...... EN ISO 3506
...... EN 20898. - Corrosion resisting steel bolts and nuts:...... EN ISO 3506
...... EN 20898
...... EN 10088. - Steel pipes and fittings:...... EN ISO 559
...... EN ISO 2604
...... EN ISO 4200
...... EN ISO 5252. - Bronze:...... E 44158
...... EN ISO 5755
Alternative materials shall be submitted to the Engineer's approval.
1.2.2.3.Testing of materials
All materials shall be tested in compliance with the relevant European or ASTM or similar acceptable standards. In particular:
- CCH 70-2 for the castings.
- CS GFF 3-72 or equivalent for the forgings.
- ASTM for steel plates pipes and laminated products.
1.2.2.4.Cast steels and castings
Before any part is cast, drawings of the major items showing the proposed locations of the samples which are to be sent for mechanical and chemical tests, shall be submitted for the Engineer's approval.
Blow holes and all other such defects which become apparent after cleaning or machining must be ground to sound metal before any rectification is undertaken.
Castings shall not be twisted nor show any other form of distortion, nor increase in their dimensions (above that already taken into account) which could cause interference with other parts. The metal structure of the castings shall be homogeneous and free of all nonmetallic impurities.
If, at any point of a critical section, the casting exhibits any unacceptably high concentration of impurities or alloying elements, the part will be rejected.
Major castings shall be submitted to ultrasonic inspection or radiographic examination where the results of ultrasonic testing is doubtful or not practical. These tests shall be complemented by magnetic particle inspection or dye penetration test.
The Manufacturer shall establish a quality sheet for each major casting.
Castings exhibiting defects of severity levels 4 or 5 in category A through E in accordance with ASTME 186 will be rejected.
Casting defects shall only be corrected by welders of the highest quality using the best welding techniques. All castings requiring rectification during any stage of the manufacturing process after they have been initially annealed, shall, unless otherwise indicated, be re-annealed.
Casting defects which require correction by welding shall be reported to the Engineer and shown on a drawing or by means of photographs. Approval shall be obtained from the Engineer before the corrective work is carried out.
1.2.3.Weldings
1.2.3.1.Qualification
For pressure tanks and hydraulic cylinders, the qualification of welding procedures and welders shall be in accordance with the requirements of ASME, Boiler and Pressure Vessel Code, Section IX.
For other components the qualification of welding procedures and welders shall conform either to ASME, Section VIII, Division 1, Section IX or the Standard Qualification Procedure of the American Welding Society at the Contractor's option.
Other welding standards and procedures translated in English will be accepted only to the extent that they conform to the above accepted codes and specifications. Exceptions to these standards and procedures will be made only where approved in writing by the Engineer.
1.2.3.2.Welding
Welding shall be performed by the electricarc method. Electroslag welding will also be permitted.
All welds shall be made continuous. Welds on gate or other submerged equipment shall be watertight. Butt welds shall be full penetration welds welded from both sides.
Contractor will provide sufficient temporary bracing to control distortion during welding.
1.2.3.3.Welded structures - stress relieving
Components, mainly those made up of large crosssection members, welded to the middle of the section or having large weld beads, shall be given stressrelieving heat treatment. This treatment shall apply in particular to:
a.Components which will have to be precision machined;
b.Structures exposed to buckling forces;
c.High carbon steel components;
d.Equipment submitted to internal or external pressure.
This list is given for guidance purposes and shall not relieve the Contractor of his responsibility.
1.2.3.4.Weld finish
Welds shall display good appearance and shall be suitable for painting. Structural welds shall be ground.
Final machining of welded parts shall be performed after welding and if applicable after stress relieving.
1.2.3.5.Weld testing
Non-destructive tests shall be in accordance with EN 10246.
For each item of equipment the Contractor shall propose for the Engineer's approval the type and extent of non-destructive weld testing.
A.The Contractor will proceed with examination of at least 20% of the weld lengths completed by each welder.
Butt welds will be given radiographic test. The Contractor shall propose the best suited type of test for welds other than butt welds.
B.Welds on pressure tanks and servomotors shall be fully tested.
C.In addition to the requirements A, all main welds shall be fully tested by ultrasonic and magnetic particle or dye penetrant tests complemented by radiographic examination where interpretation by other methods is unclear.
D.Minor welds shall be spot tested.
Examination of welds and acceptance or rejection will comply EN 10246.
1.2.3.6.Weld repairs
Defective welds shall be repaired by removing the weld material from the defective zone until sound metal is reached. The weld shall then be remade. Repaired areas shall be subjected to a new radiographic examination.
If a radiograph reveals an unacceptable zone, an extra radiograph will be taken on each side of the said zone.
If the new radiographs do not indicate any defect that would require rejection of the weld, only the zone covered by the first radiograph will be repaired. If further unacceptable defects are indicated, a complete radiographic examination shall be carried out.
Any given weld area cannot be repaired more than twice.
1.2.3.7.Electrodes
Electrodes must be stored under the conditions specified by the supplier and used within a maximum time of six months as from their date of manufacture. If this duration is to be exceeded, the Engineer will have the right to require the execution of new electrode quality tests.
For electrodes particularly sensitive to humidity (especially basic electrodes), if they have not been stored in a dry condition in perfectly watertight wrappings, they shall be baked before use, according to the supplier's instructions.
1.2.4.General provisions for equipment design
1.2.4.1.Wear
The Contractor shall be considered to be fully aware of the properties of the water used and the atmospheric conditions and, accordingly, under normal operating conditions, the equipment supplied shall not be subject to any abnormal wear.
All parts of equipment subject to waterinduced wear shall be provided with interchangeable parts that can be easily refilled by welding or replaced. These interchangeable parts shall be made from a material selected in relation to the intended use and the probable wear of the part. The Contractor shall indicate the composition and properties of the materials used on the basis of analyses carried out by the suppliers. He shall specify the type of electrode suitable for refilling by welding if this process is used. The design of bearings shall be such that no frictioninduced corrosion shall occur. The absence of any such wear will be checked at the end of the period of guarantee during equipment inspections.
The design of bearings shall be such that no friction-induced corrosion shall occur. The absence of any such wear will be checked at the end of the period of guarantee during equipment inspections.
All electrical equipment parts liable to normal or accidental wear shall be designed to resist the action of atmospheric agents and climatic conditions.
1.2.4.2.Noise
The project is designed to limit noise as much as possible.
- In technical equipment rooms:
The sound power radiated by all the equipment during maximum operation must not exceed the following values (per octave band):
Frequency in Hz / 25 / 250 / 500 / 1000 / 2000 / 4000 / 8000Log in dBA / 82 / 82 / 78 / 75 / 72 / 69 / 65
Overall value: 80 dBA.
- Generally speaking, the levels must not be in excess of 80 dBA at 3 m of each equipment.
1.2.4.3.Vibrations
During normal operation, the vibration r.m.s velocity, measured on the unit bearing supports, shall not exceed 4.5 mm/s. The vibration r.m.s speed is defined in standard VDI 2056.
The various manoeuvres of the gate and valve equipment shall be carried out under all possible loads without any harmful vibration or excessive noise occurring.
The knife edge of each gate shall be streamlined and designed to prevent vibrations regardless of their degree of opening.
1.2.4.4.Access and protection equipment
Provision shall be made for access to and protection of the equipment so as to ensure safety during operation, maintenance and inspection. All rotating parts such as wheels, shafts, transmission belts and all live electrical equipment shall be suitably protected by metal housings. Such provision is to be made at the locations and in the positions approved by the Engineer.
The Contractor shall supply all catwalks, platforms, ladders, railings, trapdoors, manholes, and access hatches tied up to the equipment and necessary for proper operation, maintenance and personal safety.
The Contractor shall submit to the Engineer for approval his proposals for the passage of gutters and for the locations of trapdoors, platforms, access doors and ladders, together will all dimensions of spaces to be allowed for the passage of equipment.
1.2.4.5.Arrangement of operating equipment
No manual controls for lifting or pulling manoeuvres shall require a force of more than 200 Newton, and no manual controls involving the operation of a wheel crank shall require a force of more than 100 Newton.
Wheel cranks shall be located approximately 1 m above floors or platforms. The controls and measuring instruments shall be readily accessible, without any need for special equipment, and clearly marked with identification numbers.
1.2.4.6.Handling and dismantling
All equipment shall be installed by using the normal operational ways. No acceptance will be done by the Engineer for installations using exceptional means.
Equipment shall be designed for easy dismantling and maintenance operations. Dismantling and maintenance of electrical equipment shall be possible without stopping or disturbing other equipment in its vicinity.
All equipment or parts of equipment designed to be dismantled and handled shall be provided with:
a.Lifting rings, lugs, hoisting collars;
b.Slings, chassis and special handling apparatus such as: grappling beams, monorails, trolleys, jacks, pulley and ratchet systems, etc.;
c.Special jack screws appropriately located and in sufficient numbers for the dismantling of the relevant parts.
For heavy components, the Contractor shall provide special facilities for lifting each component. The Contractor shall also provide the necessary lifting gear for this equipment such as manually or electrically operated monorail hoists, hydraulic jacks, etc.
The above equipment shall be included in the Contractor's supply and shall be retained by the Employer.
1.2.4.7.Interchangeability
All machined parts included in winches, pumps, gears, etc. and all moving parts in general, shall be interchangeable and capable of being easily erected on a similar type of apparatus, except for standardised equipment.
For all the contract equipment, all electrical or hydraulic apparatus, equipment, instruments and accessories (for air, water or oil circuits) of the same rating and designed to perform the same functions or operate under comparable conditions within a given operating range, shall be identical and interchangeable.
If certain modifications are made to the equipment during manufacture or erection, these modifications must be submitted for the Engineer's prior approval and shall be made to all the equipment of the same type.
At his own expense, the Contractor shall keep for a minimum period of ten years all the manufacturing drawings and all design data likely to be of use in making repairs or possible replacement of components of the equipment.
1.2.4.8.Temperature rise
The maximum temperature of metal parts of bearings and thrust bearings and that of lubricating oil shall be:
- Metal parts:...... 80°C.
- Lubricating oil:...... 60°C.
These temperatures when reached shall trigger an alarm in the control room.
The temperatures hereunder shall trigger emergency shut down of the unit:
- Metal parts:...... 85°C.
- Lubricating oil:...... 65°C.
The temperature rise of metal parts of bearings, thrust bearings, reduction gears and other mechanical systems shall not exceed 40°C above the ambient temperature or, in the case of outdoor equipment, 40°C above the outdoor temperature in the shade.
The rise in temperature of lubricating oil, measured around the metal parts quoted above shall not be more than 30°C above the ambient temperature or, in the case of outdoor equipment, 30°C above the outdoor temperature in the shade.
1.2.4.9.Lubrication
Lubrication devices and systems are included in the supply. Lubricating bearing materials shall be submitted to the Engineer's approval.
Self-lubricating systems will be provided wherever possible and are mandatory for submerged or temporarily submerged equipment unless the loads applied prevent their use.
Self-lubricating systems for submerged or partially submerged parts shall be provided with protective seals.
The systems proposed shall be of proved and referenced design. References shall be supplied by the Contractor.
1.2.4.10.Operating speeds and loads
The operating speeds defined in the technical specifications shall be guaranteed under normal operating conditions and under all loads within a 5% tolerance band.
The maximum operating loads specified by the Contractor shall be considered as guaranteed.
1.2.4.11.Nameplates
All equipment shall have a permanent engraved metal nameplate secured by screws clearly showing all pertinent information regarding the equipment, in the English language, including at least the following:
a.Manufacturer's name and address,
b.Name, type, serial number and other equipment identification data,
c.Rating and other design data,
d.Date of manufacture.
1.2.5.Design of miscellaneous detail equipment
1.2.5.1.Auxiliary pipework and pressure tanks
Pipework shall be supplied with the corresponding flanges, nuts and bolts, threaded unions, isolating valves (cast iron excluded), supports and anchoring.
Pipework design shall comply with the following values:
a.Slope greater than 1% for the drainage lines.
b.Water and oil flow velocities not to exceed 4 m/s.
Pipework embedded in concrete shall be systematically tested under pressure before concreting. All pipe end seals or blank flanges necessary for these tests shall be provided by the Contractor. No pipework made of malleable materials, such as lead, copper, etc. shall be embedded in concrete.
Pipe internal and external protection shall be by hot galvanizing. Subsequently, after each welding operation, the galvanization is to be repaired by wire brushing and application of a compatible enriched zinc paint.
Galvanization is not required for oil piping. The external surface of the oil pipes shall be protected by painting as per Section 01010-Corrosion protection.
All flanges and couplings shall be suitably placed to facilitate dismantling of corresponding equipment and appliances, with a sufficient number of isolation valves to avoid loss of fluid when partial dismantling work is carried out.
All pipes shall be installed in order to be easily dismantled for maintenance.
Flanges and couplings shall be suitably placed to facilitate dismantling. These flanges and couplings shall be indicated on drawings, with the dimensions.