HUMAN FACTOR ENGINEERING - VALVES:- Ergonomics and Anthropometry in Engineering Design

HUMAN FACTOR ENGINEERING - VALVES

VALVE CRITICALITY ANALYSIS - IMPORTANCE TO HUMAN FACTOR ENGINEERING

Valves are critically rated with the aim of minimizing risks to health and safety, balancing ease of access for operations as well as ensuring that risk or probability of human error is kept as low as reasonably practicable.

Fig 1 - Typical Ball Valve dimension and weight

For this reason, valves are carefully categorized based on functionality, with a view to affecting and determining its best orientation and position. They include:-

LAYOUT OF AN OIL AND GAS FACILITY - THINGS TO CONSIDER

PLANT LAYOUT CRITERIA AND PHILOSOPHY 

LAY-DOWN AREA
A Lay-down area is a construction term, which refers to a portion of the site, set aside for temporary storage of equipment.

Contrary to popular misconception that a lay-down area is a portion meant for maintenance purposes, a lay-down area is in actual fact, a hard concrete filled area set aside for temporary storage of equipment.

PLANT LAYOUT PHILOSOPHY
So many criteria are considered when determining the requisite and appropriate spacing between equipment on site.

These criteria are usually based on the classification of such equipment within the facility.

Equipment are usually classified into two. They are:-

1. Process Equipment
2. Utility Equipment

Process Equipment are equipment that are directly involved in the handling of the process fluids (crude or gas). They consists of equipment that perform some of the following functions:-

a. Separation
b. Cooling/Refrigeration
c. Heating
d. Fluid transfer (pumps) etc

Some example of Process equipment includes:-

i. Heat Medium Skid ix. Chillers
ii. Surge Vessel x. Booster Compressors
iii. Slug Catcher xi. Pumps etc
iv. Inlet Separators
vii. Distillation Columns
viii. Flare Knock-out drums

Utility Equipment or packages on the other hand are those that are not directly involved in the handling of the process fluid. They however provide support for the smoooth running of the process packages. They consists of equipment that perform the following functions:-

a. Power  Supply
b. Drainage (closed and open)
c. Water Supply
d. Fuel Supply etc

Some examples of Utility packages includes:-

i. Gas Generator
ii. Diesel Storage Tanks
iii. Open Drain System
iv. Closed Drain System
v. Supply Water Tank etc

Plant layout is a crucial factor in the economics and safety of a process plant. Some of the basic factors that engineers consider while determining the requisite spacing between process and utility equipment includes:-

1. Process flow Principle
2. Hazards Assessment - Classification, Ranking and Ratings
3. Containment of Accidents
4. Limitation of Exposure
5. Escape
6. Efficiency and safety in Operation
7. Efficiency ans safety in Maintenance
8. Fire fighting Access & Fire Protection
9. Access for Emergency
10. Security
11. Ventilation

Plant layout can have a large impact on plant economics. Additional space tends to increase safety, but is expensive in terms of land and also in additional pipework and operating costs.
Space therefore needs to be provided where necessary for safety concerns, and not wasted.


HAZARDOUS AREA CLASSIFICATION

When an Electrical Equipment is used in, around or near an atmosphere that has flammable gases or vapors, flammable liquids, combustible dusts, ignitable fibers, there is always a possibility or risk that a fire or explosion might occur.

Pressure Vessels For Oil & Gas Facilities: What Engineers Need to Know

Pressure Vessels for Oil and Gas Facilities: What Engineers Need to Know

A pressure vessel is a closed container designed to hold gases or liquids at a pressure substantially different from the ambient pressure. The pressure differential is dangerous, and fatal accidents have occurred in the history of pressure vessel development and operation.

Pressure Vessel, Post Fabrication

Pressure vessels are classified as static equipment as they do not have any rotating member.

The term separator in oilfield terminology designates a pressure vessel used for separating well fluids produced from oil and gas wells into gaseous and liquid components. 

Schematic Of Separation Process

A separator for petroleum production is a large vessel designed to separate production fluids into their constituent components of oil, gas and water. 

BASICS OF FLARE SYSTEMS

FLARE SYSTEMS

The flare is the last line of defence in the safe emergency release system in a chemical plant or refinery.

It is a fail-safe option used in the disposal of purged and wasted products from refineries, vented gases from blast furnaces, gaseous water from chemical industries, unrecoverable gases from oil wells etc.

Typical Flare Stack During Operation

The flare provides a means of safe disposal of the vapor streams from its facilities, by burning them under controlled conditions such that adjacent equipment or personnel are not exposed to hazards, and at the same time obeying the environmental regulation of pollution control and public relations requirements.

Galvanization Process: Things Every Engineer Must Know

Galvanization Process: Things Every Engineer Must Know

Galvanization is the practice of immersing clean, oxide-free iron or steel into molten zinc in order to form a zinc coating that is metallurgically bonded to the iron or steel’s surface. This zinc coating protects the surface of the galvanized metal against corrosion, by providing protection to the iron or steel.

Due to the unique corrosion resistance of Zinc, it is the widely used as a sacrificial anode, providing even better protection to the steel that ordinarily painted steel surfaces.

The hot dip The hot dip galvanizing process is adaptable to coating nearly all types of fabricated and non-fabricated products such as wire, tanks, sheets, strip, pipes and The hot dip galvanizing process is adaptable to coating nearly all types of fabricated and non-fabricated products such as wire, tanks, sheets, strip, pipes and tubes, fittings, hardware, wire cloth, hollow-ware, and structural assemblies.

All galvanizing consists of four fundamental steps:

1. Surface preparation
2. Pre-fluxing
3. Galvanizing
4. Finishing

The preparation steps consist of cleaning and pickling operations that free the surface of dirt, grease, rust and scale. It is dipped into a caustic soda to remove oil, grease, paint and other marking. 

An acid solution is used to remove rust. The preflux step serves to dissolve any oxide that may have formed on the iron or steel surface after pickling and prevents further rust from forming.