SITE WORK
DESIGNATIONS AND RESPONSIBILITIES
Responsibilities
Project Manager
To ensure that all preparation and application works are carried out according to
that contact specific
ations, method statement, Saudi Aramco Engineering Specification
and manufacturer data sheet.
To ensure that the progressing of work is carried out according to the planned
program and as per the approved Method Statement To ensure that all the manpower, equipment and materials required to execute the
Work are available To ensure that all related quality procedures are practiced and implemented
To ensure that all safety matters related to this procedure are being observed.
Site Engineer
Coordinate all the site activities in accordance with approved IFC, Shop drawings, project specification, approved method statement and Saudi Aramco Engineering
Standards.
To provide all necessary information and distribute responsibilities to his team. To monitor the progress of work in relation with work program and to report to
the PM.
To ensure that the installer is well trained for this type of work.
To coordinate with safety officer and to ensure that the works are carried out in safe
practicing method.
Site engineer shall inform mechanical Quality Control Inspector for internal inspection
to check work has been done accordance to IFC, Shop Drawings, Saudi ARAMCO
standards prior to preparing internal RFI for inspection and the time schedule.
KNOWLEDGE ABOUT WELDING
WIELDING KNOWLEDGE
KNOWLEDGE ABOUT WELDING
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HVAC WORK IN INDIA
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AIR PRESSURE
Low Pressure Fittings for Residential and Light Commercial HVAC Applications
Over the years, the terms low pressure and high pressure in duct system design have been given a wide latitude of meanings in the HVAC industry, and they are frequently (and, sometimes simultaneously) applied to “velocity” as well as pressure because these factors are inter-dependent.
Depending on application, the dividing line between high and low pressure has been variously defined between 1500 to 2500 fpm, and nominally as 2000 fpm; and empirical data has shown that duct sections operate satisfactorily over the above range of velocities at 1″ water gage (wg).
Low pressure systems are chosen where duct space allows, where air noise is a consideration, and where particle conveyance such as wood chips or grain is not a requirement.
Space limitations in modern buildings have restricted the size of air conditioning ducts and equipment. Therefore, to convey the necessary volumes of air, higher velocities must be employed. Increased velocities produce higher duct friction losses. In order to maintain flow against the higher duct friction, it is necessary to have greater pressures at the air source. Therefore, the terms “high pressure” and “high velocity” generally go hand in hand. Conversely, this is true of “low pressure” and “low velocity”.
The use of the terms “high velocity” and “high and medium pressure” in this catalog refer to any static pressure class of 3″ wg or greater, and “low pressure” refers to 2″ wg or less.
SMACNA recommendations on pressure and velocity are shown in the table below. The listed classifications pertain to ducts only. Casing and plenum construction designs are provided in the “High Pressure” manual, but their respective designs have been based on historical acceptability.
| Pressure Velocity Classification 1 | ||||
| Former Duct Class |
Pressure Rating |
Pressure | Seal Class 2 |
Seal Class 3 |
| High Pres. |
10″ | Pos. | A | 2000 Up |
| Medium Pres. |
6″ | Pos. | A | 2000 Up |
| Medium Pres. |
4″ | Pos. | A | 2000 Up |
| Medium Pres. |
3″ | Pos. or Neg. |
A | 4000 Dn |
| Low Pres. |
2″ | Pos. or Neg. |
2000 Dn | |
| Low Pres. |
1″ | Pos. or Neg. |
2000 Dn | |
| Low Pres. |
1/2″ | Pos. or Neg. |
1500 Dn | |
1Reproduced in part by Permission From SMACNA High Pressure Duct Standards – 3rd Ed.
2Seal Class A: All seams, joints, fastener penetrations and connections sealed.
3General velocity level through this pressure rated section of the system. Certain points may have higher or lower velocities, e.g., fan outlet or restricted passage, yet not require a different pressure class. The designer makes determinations of duct class after analyzing velocities and operating pressures
1.
the pressure exerted by the earth’s atmosphere at any given point, being the product of the mass of the atmospheric column of the unit area above the given point and of the gravitational acceleration at the given point.
2.
a value of standard or normal atmospheric pressure, equivalent to the pressure exerted by a column of mercury 29.92 inches (760 mm) high, or 1013 millibars (101.3 kilopascals).
air pressure. air pressure. noun. The definition of air pressure is the force exerted onto a surface by the weight of the air. An example of air pressure is the average sea-level air pressure of 101.325 kPA.
The definition of air pressure is the force exerted onto a surface by the weight of the air.
the pressure of atmospheric or compressed air.
IN OUR DAILY LANGUAGE
The weight of the air mass, or atmosphere,that envelopes Earth exerts pressure on all points of the planet’ssurface. Meteorologists use barometers to measure this atmosphericpressure (also called barometric pressure). At sea level theatmospheric pressure is approximately 1 kilogram per squarecentimeter (14.7 pounds per square inch), which will cause a columnof mercury in a mercury barometer to rise 760 millimeters (30.4inches). The pressure is frequently expressed in pascals, after theFrench mathematician and philosopher Blaise Pascal, who studied thetransmission of pressure in confined fluids. Subtle variations inatmospheric pressure greatly affect the weather. Low pressuregenerally brings rain. In areas of low air pressure, the air is less denseand relatively warm, which causes it to rise. The expanding and risingair naturally cools, and the water vapor in the air condenses, formingclouds and the drops that fall as rain. In high pressure areas,conversely, the air is dense and relatively cool, which causes it tosink. The water vapor in the sinking air does not condense, leavingthe skies sunny and clear.
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