science engineering Flashcards
5 steps in material selection
- Identify condition of exposure ICE
- Establish strategy ofevaluating candidate materials
- Identify candidate materials
- Evaluating materials ofconstruction
- Selecting the final materialswith necessary documentation
What are 3 Chemical Engineering Design Works?
- Modification and additions to existing plants. usually carried out by the plant design group.
- New production capacity to meet growing sales demand, and the sale of established processes by contractors. Repetition of existing designs, with only minor design changes.
- New processes, developed from laboratory research, through pilot plant, to a commercial process. Even here, most of the unit operations and process equipment will use established designs.
What are the 3 Design Documents?
- Calculation sheets.
- Drawings.
- Specification sheets.
What are 3 Structural Corrosions?
- Graphitic corrosion
- Parting or de-alloying corrosion
- Dezincification or biological corrosion
What are the 5 Standards for Materials?
- AISI (American Iron & Steel Institutes)
- SAE (Society of Automotive Engineers)
- ANSI (American National Standard Institutes)
- ASME (American Society of Mechanical Engineers)
- ASTM (American Society for Testing Material) or ISO (International Organization for Standardization)
- ISO (International Organization for Standardization)
What are the 3 types of Stainless Steel?
- Ferritic 13-20% Cr, <0.1%C, with no nickel
- Austenitic 18-20% Cr, >7% Ni.
- Martensitic 12-14% Cr, 0.2 to 0.4%C, up to 2% Ni.
6 Contents of Specification Sheet
- Identification
- Function
- Operation
- Materials handled
- Basic design data
- Essential controls
- Insulation requirements
- Allowable tolerances
- Special information
Modern Steps in Design
- Determine Customer Needs
- Set Design Specifications
- Generate Design Concepts
- Build Performance Models
- Predict Fitness of Service
- R&D if Needed
- Customer Approval
- Economic Evaluation,Optimization and Select Design
- Design Specification andEquipment Selection
- Procurement and Construction
- Begin Operation
General Classification of Equipment
- Columns (Separation/Purification equipment)
- Vessels (Handling/Preparation/Storage Equipment/Separation/Purification)
- Reactors (Reaction Equipment)
- Heat Exchangers and Furnaces (Heat Transfer Equipment)
- Pumps, compressors, and transport equipment
- Instrument (Process Control Equipment)
- Special Equipment(Purification, separation)
an acceleration in the rate of corrosion attack in metal due to therelative motion of a corrosive fluid & metalsurface
Erosion
minimized by using harder materials, minimizing friction (via lubrication), or designing equipment so that no relative movement of parts takes place
Fretting Corrosion
localized form of corrosion usually associated with a stagnant solution on the micro- environmental level
Crevice
aka ‘dissimilar metal corrosion’ or wrongly ‘electrolysis’; corrosion damage induced when 2 dissimilar materials are coupled in a corrosive electrolyte
Galvanic Corrosion
aka selective leaching (selective removal of 1 element from an alloy by corrosion processes); in a gray cast iron, a brittle graphite skeleton remains following preferential iron dissolution
Dealloying/Graphitic Corrosion
there are several categories of hydrogen phenomena that are localized in nature; atomic hydrogen (not the molecule) is the smallest atom & is small enough to readily diffuse through a metallic structure; when the crystal lattice is in contact or saturated w/ atomic hydrogen, the mechanical properties of many metals & allows are diminished
Hydrogen Cracking
associated w/ a flow-induced mechanical removal of the protective surface film that results in a subsequent corrosion rate increase via ether electrochemical or chemical processes; mechanical destruction of a metal by abrasion or attrition caused by the flow of liquid or gas (w/ or w/o suspended solids)
Erosion-Corrosion
occurs when a fluid’soperational pressure drops below its vapor pressurecausing gaspockets & bubbles to form& collapse w/c can occurin a rather explosive & dramatic fashion
Cavitation
‘localized corrosion causedby turbulent flow’;entrained air bubblestend to accelerate this action, as do suspended solids; occurs in pumps, valves,orifices, on heat-exchanger tubes, & at elbows & tees in pipelines
Impingement
result of the combined action of an alternating or cycling stresses& a corrosive environment; this thought to cause ruptureof the protective passive film upon w/c corrosion is accelerated
Corrosion-Fatigue
corrosion damage at the asperities of contact surfaces; this damage is induced under load & in the presence of repeated relative surface motion as induced for example by vibration or the protective film on the metal surfaces is removed by the rubbing action
Fretting Corrosion
selective corrosion in the grain boundaries of a metal or alloy w/o appreciable attack on the grains or crystals themselves; when severe, this attack causes a loss of strength& ductility out of proportion to the amount of metal actually destroyed by corrosion
Intergranular Corrosion
resulting corrosion when microbial natural activities create oxidizing, reducing, acidic, or other conditions under w/c 1 form of ametal or material of construction is chemically transformed to another
Microbiological Influenced Corrosion (MIC)
can be minimized by electrochemical method of corrosion control has found wide application in the protection of carbon steel underground structures such as pipelines& tanks from external soil corrosion; 2 methods of providing cathodic protection are sacrificial-anode method & impressed-emf method
Galvanic Corrosion
use of inhibitors as additives is an important means of combating corrosion; inhibitors will decrease corrosion of metals in the environment, the effectiveness of a given inhibitor generally increases w/ an increase in concentration of inhibitor; the amount off inhibitor present is critical in that a deficiency may result to this type
Pitting Corrosion
cracking induced from the combined influence of tensile stress & corrosive environment; impact of this corrosion on a material usually falls between dry cracking & fatigue threshold of that material
Stress Corrosion Cracking
austeniticstainless steel that are not stabilized or of extra-low carbon type when come in contactw/ hot nitric acid or heat at450°C to 843°C will result to this type
Inter-granular
can be best prevented by insulation
Galvanic Corrosion
aluminum & stainless allows in aqueous solutions containing chlorides are very prone to this this type
Pitting
mercury attack on aluminum allows & attack of stainless steels by molten zinc or aluminum; mercury or molten zinc will penetrate the metal along grain boundaries to cause catastrophic failure w/c will result to this type
Liquid Metal Corrosion
- Material of constructions that has the least amount of iron.
a. Inconel
b. Hastelloy
c.Stainless Steel
d. Monel
e. Worthite
d. Monel
- Considered as medium alloys i.e. proprietary alloys w/ somewhat better corrosion resistance than stainless steels& have extensive application in sulfuric acid system.
a. Worthite
b. Chlorimet 2
c. Inconel600
d. Monel 400
e. Cupronickel
a. Worthite
- The essential alloying element for steel and most of the metallicmaterial of construction that will be used above 550°C.
a. Ni
b. Cr
c. Mo
d. P
e. Si
b. Cr
- For most organic fluids,w/c among the ff materials of construction will you recommend?
a. Mild Steel
b.Stainless Steel
c. Brass
d. Monel
e. Aluminum
b. Stainless Steel
- W/c of the materials of construction cannot be used for low temperature condition?
a. Aluminum
b. Copper
c.Stainless Steel
d. Nickel Steel
e.None ofthe choices
e. None of the choices
- Most commonly used type of stainless steel for pumps,valves, & fittings
a. S31600
b. S44600
c. S40300
d. S30300
e. None ofthechoices
a. S31600
- Muntz metal is a variety of alloy brass whose major component is 60% copper& 40% ofa. Iron
b. Nickel
c. Aluminum
d. Zinc
e. Chromium
d. Zinc
- Among the reactive& refractory metals(UNS R00001 – R99999), this metal was originally developedas a material of construction for atomic reactors
a. Zirconium
b. Tantalum
c. Titanium
d. Tungsten
e. Niobium
a. Zirconium
- For the fabrication of cryogenic equipment, w/c among the materials of construction is not recommendable?
a. SS304
b. Copper
c. Aluminum
d. Tungsten
e. CarbonSteel
e. Carbon Steel
- One (1) methodof combating corrosionis w/ the use of inhibitors. W/c among these is not used as an inhibitor in minimizing corrosion of iron & steel in acid &aqueous solution?
a.Chromates
b. Phosphates
c. Nitrates
d. Amines
e. Silicates
c. Nitrates
- In a design specification sheet of a shell & tube heat exchanger, the ff are design parameters that need to bespecified EXCEPT for
a. Equipment Type
b. Material of Construction
c. Design Pressure
d. Shell Height
e. Tube Diameter
d. Shell Height
- “Passivation” is an operation wherein the surface of the metal isoxidized to a passive state i.e. the surface is treated w/ nitric acid & then rinsed w/ water. This will increasethe resistance to corrosion. This process is commonly done to
a. Nickel Alloys
b. Copper Alloys
c. Plain Carbon Steel
d. Stainless Steel
e. Aluminum
d. Stainless Steel
- An alloying elementfor stainless steel w/c is used to retard oxidizingpower of a solution by providing tight adherent oxide film or layers of adsorbed oxygenspecifically at the temperature above 550°C
a. Nickel
b. Manganese
c. Molybdenum
d. Chromium
e. Vanadium
d. Chromium
- Commercial pure aluminum can be strengthened by what method of treatment
a. Heat Treatment
b. Sintering
c.Cold Working
d. Alloying
e.Carbonization
c. Cold Working
- In UNS system, materialcode & specification starting w/ letterF stands for
a. Corrosion ResistantSteel
b. Special Steels
c. C-Steel
d. Cast Iron
e. Tool Steel
d. Cast Iron
- In design, when dissimilar metalsare to be used in contact w/ each other & exposed to an electrically conducting solution, w/c amongthe paired metalshas the leastpossibility of being attacked by a galvaniccorrosion?
a. Sn-Ni
b.Pt-Mg
c. Al-Monel
d. Zn-Cu
e. Ag-Pb
a. Sn-Ni
- At high pH, w/c amongthe metals has the highestcorrosion rate?
a. Fe
b. Pt
c. Zn
d. Cu
e. Ni
c. Zn
- W/c among the choicesis not part of designdocumentation?
a. Flow Diagram
b. Specification Sheet
c. Material of Construction
d. Plant & Piping Layout
e. None of the choices
c. Material of Construction
- W/c among the choices is not a preliminary design process?
a. Set Design Objective
b. Evaluate
c. Optimize
d. Operate
e. Generate
d. Operate
Based on the process synthesis, process operations should be indicated on this type of flow diagram
a. Input/Output
b. Function
c. Operation
d. Block
e. Generate
b. Function
- 67% Ni and 30% Cu is commonly known as: (PHB 8th Ed. 25-33)
a. Cupronickel
b. incoloy
c. Hastelloy
d. monel
e.Inconel
d. monel
- Commercial pure aluminum can be strengthened by cold working. Forsafe design consideration, the highest permissible temperature for Al is: (PHB 8th Ed. 25-33)
a. 400 C
b. 200 C
c.150 C
d.300 C
e. 85C
c. 150 C
- An alloying element which is used to retard oxidizing power of asolution by providing tight adherent oxide film or layers of adsorbed oxygenspecifically at temperature above 550 C, as in the case of stainless steel is:
a. chromium
b.silicon
c. manganese
d. molybdenum
e. nickel
a. chromium
- An aggregate of inert reinforcing particles in an amorphous matrixof hardened cement paste is called:
a. Porcelain
b. glass
c. ceramics
d. concrete
e. refractories
d. concrete
- Among the different types of austenitic steels commerciallyavailable, commonly used type is:
a. S31600
b. S30400
c.S32100
d.S31000
e.S41000
b. S30400
- Most commonly used type of stainless steel for pumps, valves, andfittings is:
a. S31600
b. 544600
c.S40300
d.S30300
e. none
a. S31600
- Durion and durichlor are type of high silicon-cast iron with 13% to16% Si. Their main difference is the presence of 4% of this alloying element inDurichlor: (From the net)
a. Chromium
b. Chloride
c.Copper
d.Molybdenum
e. Nickel
a. Chromium
- Hastelloy, monel, inconel, and incoloy have something in common. Allmaterials of construction contain in a very high percentage of this element.
a. Iron
b. Nickel
c.Copper
d.Molybdenum
e. chromium
b. Nickel
- Which among the choices is not a cast iron: (A and B from sir’s modules, C found on the net, D I cannotfind)
a. Gray cast
b. white cast
c. ductile cast
d. alloy cast iron
e.none
d. alloy cast iron
- Which among the components is not a component of Inconel 625
a. Nickel
b. Chromium
c. Copper
d.Iron
e. Molybdenum
c. Copper
- In UNS system, material code and specification starting with theletter F stands for:
a.Corrosion-resistant steel
b.Special steels
c. C-steel
d. Cast iron
e.Tool steel
d. Cast iron
- For most organic fluids, which among the following material ofconstruction will you recommend?
a. Mild steel
b. Stainless steel
c. Plain Carbon steel
d.Monel
e. Al
b. Stainless steel
- At elevated temperature and significant partial pressure, hydrogenwill penetrate carbon steel and reaction with carbon in the steel in will form:(From the net)
a. Hydrazine
b. Methane
c.Carbonates
d. HCN
e. Hydrogen halide
b. Methane
- Which among the pure substance is non-oxidizing agent? (Kasi walang O?)
a. Sulfuric Acid
b. Cl2
c. H2O2
d. Nitric Acid
e. Ammonium Nitrate
b. Cl2
- One (1) method of combatting corrosion is with the use ofinhibitors. Which among these is not used as an inhibitor in minimizingcorrosion of iron and steel in acid and aqueous solution:
a. chromates
b. phosphates
c. nitrates
d. amines
e. Silicates
c. nitrates
