NACE CIP Level 2 Questions and Answers|
Latest Update
applications for powder coat electrostatic spray, dip method, flame spray, roto-lining
plural component systems(2 types) 1 fixed ratio: two pumps that operate with afixed
throw on each leg, pistons swapped to change ratio
2 adjustable ratio machine: ratio controlled auto. by machine
feed mechanisms for plural component systems(2 types) 1) blend components in a
manifold and mix them in an in line static mixer
2) mixed components at spray gun tip
pros of hot spray system -accurate mixing
-spray thick material without use of thinner
-spray material with short pot-life
cons of hot spray system -expensive equipment
-high voltage electricity hazard
-difficult to use
inspection concern for hot spray system important to confirm mix ratio and take
temperature readings at the nozzle
,thick barrier linings polymeric sheet materials(ex: PVC, polyethylene, polypropylene)
inspection concerns for thick barrier linings -proper thickness is applied
-accurate cutting of dimensions
-high voltage holiday testing needed usually on all heat welds of lining
uses for rubber sheet linings -storage/transportation of sensitive materials
-often used for tanks/membranes
-easily customizable
-abrasion resistance
vulcanization Physicochemical change from cross linking the unsaturated hydrocarbon
chain of natural rubber with sulfur and applying heat(250+300F)
3 factors of vulcanization 1) percent of sulfur & accelerant
2) temperature of cure(250-300F)
3)time of cure
Autoclave Cure method preferred for rubber curing because of better heat transfer and
shorter cure cycles, highest density and adhesion achieved
, Internal Steam Cure The pressure vessel
is used as its own autoclave. Workers
close off all openings and fill the vessel
with steam under controlled temperature
and pressure.
atmospheric steam cure vulcanization without pressure, temperature of the steam and steel
skin are closely monitored, used for field lining
Hot-water Cure equipment filled with water, and steam is injected to boil the water
chemical cure chemical reaction that occur when low - molecular weight resin molecules
(monomers) join together to form long- chain high colencular weight molecules (polymers)
inspection concerns for rubber application 1) ensure steel is new and has no defects and is
a flat plate
2)min thickness of 0.25"/10lbs or 0.5"/20.4 lbs
3)brace vessel to avoid buckling
4)check welds for continuity
fusion bond epoxy one of primary coatings used on pipelines, major inspection concern is
must always used high voltage holiday test because of dielectric strength
Latest Update
applications for powder coat electrostatic spray, dip method, flame spray, roto-lining
plural component systems(2 types) 1 fixed ratio: two pumps that operate with afixed
throw on each leg, pistons swapped to change ratio
2 adjustable ratio machine: ratio controlled auto. by machine
feed mechanisms for plural component systems(2 types) 1) blend components in a
manifold and mix them in an in line static mixer
2) mixed components at spray gun tip
pros of hot spray system -accurate mixing
-spray thick material without use of thinner
-spray material with short pot-life
cons of hot spray system -expensive equipment
-high voltage electricity hazard
-difficult to use
inspection concern for hot spray system important to confirm mix ratio and take
temperature readings at the nozzle
,thick barrier linings polymeric sheet materials(ex: PVC, polyethylene, polypropylene)
inspection concerns for thick barrier linings -proper thickness is applied
-accurate cutting of dimensions
-high voltage holiday testing needed usually on all heat welds of lining
uses for rubber sheet linings -storage/transportation of sensitive materials
-often used for tanks/membranes
-easily customizable
-abrasion resistance
vulcanization Physicochemical change from cross linking the unsaturated hydrocarbon
chain of natural rubber with sulfur and applying heat(250+300F)
3 factors of vulcanization 1) percent of sulfur & accelerant
2) temperature of cure(250-300F)
3)time of cure
Autoclave Cure method preferred for rubber curing because of better heat transfer and
shorter cure cycles, highest density and adhesion achieved
, Internal Steam Cure The pressure vessel
is used as its own autoclave. Workers
close off all openings and fill the vessel
with steam under controlled temperature
and pressure.
atmospheric steam cure vulcanization without pressure, temperature of the steam and steel
skin are closely monitored, used for field lining
Hot-water Cure equipment filled with water, and steam is injected to boil the water
chemical cure chemical reaction that occur when low - molecular weight resin molecules
(monomers) join together to form long- chain high colencular weight molecules (polymers)
inspection concerns for rubber application 1) ensure steel is new and has no defects and is
a flat plate
2)min thickness of 0.25"/10lbs or 0.5"/20.4 lbs
3)brace vessel to avoid buckling
4)check welds for continuity
fusion bond epoxy one of primary coatings used on pipelines, major inspection concern is
must always used high voltage holiday test because of dielectric strength
