Flashcards in Quiz 2 Deck (141):
What is a clean room?
A clean room is a room in which the amount of airborne particles are controlled in order to limit contamination.
What is constructed and operated in a manner to control the introduction, generation, and retention of contaminates inside a space?
A clean room
Filtered air flows into a clean room by what?
High Efficiency Particulate Air (HEPA) Filters
What are the two types of clean rooms?
True or False? Hard Wall clean rooms are typically cleaner than Soft Wall clean rooms.
Clean rooms can also be classified by the direction of air flow. What are the two directions of air flow?
Air moves parallel to the floor across the room.
Air moves from the top of the room and goes down.
Clean rooms are classified under the ISO Standard 14644. What is the least clean ISO, and what is the most clean?
Least: ISO Class 9
Most: ISO Class 1
The ISO Standard 14644, is classified base on the ___ and _____ of air borne particles in a clean room.
amount and size
The ISO Class 7 and ISO Class 5 are the ______ _____ ______.
most commonly used
True or False? Between ISO Class 7 and ISO Class 5, the more clean the room is, the more precaution must be used.
1. You must remove cardboard, paper, or fiber outer packaging before gowning up and entering the clean room. Why?
Paper and cardboard excessively shed particles, and fibers are prohibited from clean rooms.
Only clean room ______ and ____ may be used in a clean room. And if regular paper is used, it must be sealed in a _______ ______.
paper and notebooks
must be sealed in a plastic sheet
True or False? Only ball point pens without caps should be used in a clean room.
If you don't know if an item is prohibited in the clean room, consult who?
Contamination Control Engineer or your Manager
Gowning ISO Class 7 or 8; You should always gown from top to bottom. True or False?
Gowning ISO Class 5 or 6; requires you to wear a coveralls or bunny suit. Also includes a hood and boot. True or False?
Moving around quickly can produce ___ % more particles, then moving slowly.
De-Gowning goes in _____ order.
ESD is what? And must be worn under both the garment and sealed gloves.
Electro Static Discharge
Practicing proper clean room ____ is need to maintain a clean room environment, and helps insure the safety and success of a given project.
On a single Venturi Vacuum,, the brass nozzle convert the compressed air into a very tight bead of compressed air at a fast velocity, which creates the _______.
The air would come through the the brass nozzle, down through the vacuum port and through the receiver section of the pump. Which vacuum pump am I referring to?
Single Venturi Vacuum
Taking the compressed air through a nozzle, creating a vacuum in a chamber. The air is recycled through another Venturi (A brass nozzle) creating vacuum in a second stage, and creating a vacuum in a third chamber. Which vacuum pump am I referring to?
Multi Venturi Vacuum
What vacuum pump uses less compressed air and has more vacuum flow?
You can only get ___ - ___
cubic feet of vacuum flow in a single venturi.
10-15, because of size restrictions
In a multi Venturi you can get ____ cubic feet of vacuum flow.
Use a ______ when you need more than 25 cubic feet of a single body.
Bolt the manifold to the _____ 2 times. Allowing 50 cubic feet of vacuum.
If you need 100 cubic feet, you will put ____ pumps on a manifold.
200 cubic fee, you will put ___ pumps on the manifold.
Dispatch composite curing system is an ______.
out of autoclave
Uniflow air flow meaning what?
moves both horizontally and vertically offering temperature uniformity.
the precise airflow pattern and directional can be modified for each application to optimize the ___ ____ ______ for the specific part being cured.
time to temperature
Air is being directed to the part and recirculated through the ____ ____ and back into the oven for greater energy efficiency.
True or False? The composite industry is shifting to out of autoclave vacuum bagging processes.
The vacuum bagging technique begins with the _____ _____ which is typically secured on top of a movable cart.
A release agent is applied to the mold and a prepreg layup to be cured is placed on ____.
Thermocouples are then applied to the _____ lay up in all areas to ensure that the part is cured completely and uniformly.
Jack panels on the oven allow connection for as many thermocouples as necessary. Secondary thermocouples can be added as an ______ back up in case of failure.
The ____ bag is the last item to be placed and is sealed securely over the part.
The cart is rolled into the item and vacuum connection ports are attached. Vacuum hoses are hooked up up to the connection ports. The air is drawn out of the bag and the part is ready to be cured.
Utilizing the _____ point ___ system.
focal point control system
The focal point control system is _____. With remote, i/o- 4 part thermosouple systems include: vacuum systems, and compressed air systems.
Prior to starting the ___, batch data is entered is entered manually or by bar-code scan. Recipe data is added through focal points advanced recipe editor program.
All documented batch part and oven process data is appended to a main file for inspection/review. Exported to either CVS or ____ format.
True or False? Dispatch composite curing system is good for other processes like aluminum aging and basic curing.
What is step 1 of Endothermic and exothermic reactions?
Energy must be supplied to break chemical bonds.
What is step 2 of endothermic and exothermic reactions?
Energy is released when a new chemical bonds are made
What reaction is it, if more energy is RELEASED than supplied?
Exothermic (tip: an ex-lover releases energy by smashing your things)
What reaction is it, if more energy is SUPPLIED than is released?
Endothermic (tip: to prepare for the end of the world you need supplies)
A chemical reaction that requires or absorbs heat.
What is an example of endothermic?
________ reaction, heat is taken in and temperature of the substance drops
A chemical reaction that releases heat.
______ reaction, heat given off and temperature of substance rises.
More energy is given out than is taken in by burning, respiration, etc.
energy is taken in but not necessarily given out.
What are examples of exothermic?
yeast & hydrogen peroxide
Epson salts & water
What are the examples of endothermic?
acetic acid and sodium bicarbonate
It is important to mix ____ resin correctly.
Carbon fiber is ___ and ___ than fiberglass.
lighter and stiffer
The nature of carbon fiber is very ____, ___, and _____.
light, rigid, and strong
Most ____ - ____ performance products are being manufactured with carbon fiber.
Carbon fiber is very strong and very rigid, while fiber glass is ____>
strong but not as rigid
In applications where a small amount of flexibility is desired, _____ _____ is the material of choice.
In applications where a small amount of flexibility is desired, ________ is probably better suited.
_____ is better suited to extreme flex patterns.
_____ has a relatively small flex window.
any ______ composite is tough.
Fiberglass is actually a _____ material than carbon fiber.
The ability to flex farther without breaking, in general it acts as a _____ material
the incredible ____ of carbon makes it less capable of enduring certain abuses than fiberglass.
_____ strands of carbon fibers are very difficult and expensive to manufacture, while fiberglass processes much easier.
____ is considerably less expensive than carbon fiber.
What does VIP stand for?
Vacuum infusion process
What is vacuum infusion process?
Is a production process used to make parts out of fiber-reinforced polymers (FRP).
What is FRP?
____ _____ uses negative pressure to pull out air, while impregnating the reinforcement with resin.
What does VIP stand for?
Vacuum infusion process
What is a VIP?
production process used to make parts out of FRP.
How does VIP work?
Vacuum infusion uses negative pressure to pull-out air, while impregnating the reinforcement with resin.
Step 1 of VIP?
Dry material are place on either a male or female mold/ thin plastic vacuum bag is sealed
using a vacuum pump, air is evacuated and ______ _____ is applied to consolidate the dry materials. Creates a vacuum cavity.
Step 2 of VIP?
Resin is introduced into the cavity through resin feeder lines.
What are the determining factors for filling time of a VIP part?
Porosity permeability, viscosity of resin,
applied pressure difference,
flow and distance
Permeability of the materials is directly proportional to the flow of the ____.
Proper infusion requires ___ ____ unless a scored or grooved core is used. Simply put, pathways need to be created to allow the resin to flow.
The ______ the viscosity of the resin, the lower the flow speed (inversely proportional).
A more _____ resin will result in more part saturation.
The ideal viscosity falls in the range of ____ and ____ cps.
100 and 300
The bigger the gradient between pressures, the ____ the resin will flow.
Not to exceed 54 inches. Adequate flow requires a resin temperature of ___ degrees F or higher.
For the best infusion process results:
Use a very thin resin
Use very permeable materials
Create the highest pressure differential possible
When comparing cycle time of a VIP part to __________________________, it is usually slower.
hand lay-up or spray-up open molding
Composite parts made using the Vacuum Infusion Process (VIP) are superior to traditional open molding because they are:
Stronger, Lighter, Cheaper to manufacture
Inspections can be done prior to resin being introduced into the part.
If clear ____ _____ is used, the part can be studied for imperfections after infusion.
What does VOC stand for?
Volatile Organic Compounds
What does HAP stand for?
Hazardous Air Pollutants
____ is gaining popularity because of relatively low capital investment and an easily manageable learning curve.
Advantage of VIP?
Ability to conform to simple and complex shapes
Control of part thickness
A stronger laminate
FRP Composites for short, use a ______ resin as the matrix, which holds the structural fiber firmly in place.
What are common thermosetting resins?
Polyester ResinVinyl Ester ResinEpoxyPhenolicUrethane
What is the most common thermosetting resin used today?
Polyester resin, followed by vinyl ester and epoxy
What are thermosetting resin popular?
uncured, at room temperature, they are in a liquid state.his allows for convenient impregnation of reinforcing fibers such as fiberglass, carbon fiber, or Kevlar.
In thermoset resin, Laminators can easily remove all air during manufacturing, and it also allows the ability to rapidly manufacture products using______ or positive pressure pump.
____ ____ ____ Beyond ease of manufacturing, thermosetting resins can exhibit excellent properties at a low raw material cost.
(Closed Molds Manufacturing)
Properties of thermoset resins include
Excellent resistance to solvents and corrosivesResistance to heat and high temperatureFatigue strengthTailored elasticityExcellent adhesionExcellent finishing (polishing, painting, etc.)
In a thermoset resin, the raw uncured resin molecules are crossed linked through a ____ _____ ____.
catalytic chemical reaction.
Through this chemical reaction, most often exothermic, the resin creates extremely strong bonds to one another, and the resin changes state from a liquid to a solid. ____ resin
A______ thermosetting resin, once catalyzed, it cannot be reversed or reformed.
Recycle therosetts, removed the resin through _____ and are able to reclaim the reinforcing fiber.
______ _____ resins are extremely common, and we come in contact with thermoplastic resins constantly.
Thermoplastic resins are most commonly ______, meaning, the resin is formed into shapes and have no reinforcement providing strength.
Many thermoplastic products use short ____ _____ as reinforcement; most commonly fiberglass, but carbon fiber, too.
This increases the mechanical properties and is technically considered a fiber reinforced composite, however, the strength is not nearly as comparable to continuous fiber reinforced composites.
n general, FRP composites refers to the use of reinforcing fibers with a length of___ or greater.
thermoplastic resins have been used with ____ _____ creating structural composite products.
What are the two major advantages of thermoplastic composites?
Increase impact resistance
ability to reform
Raw thermoplastic composites, at room temperature, are in a ___ state.
For ____ _____ When heat and pressure impregnate a reinforcing fiber, a physical change occurs; not a chemical reaction as with a thermoset.
What is the disadvantage of thermoplastics?
Difficult to impregnate reinforcing fiber.
In thermoplastics, the resin must be heated to the ____ _____, and pressure is required to impregnate fibers, and the composite must then be cooled under this pressure.
What is the major disadvantage of thermoplastic composite?
special tooling, technique, and equipment must be used = expensive
For panels ____ tooling is normally preferred because it maintains aero quality.
What are the two exceptions to female tooling?
fier placing and filament winding
For structure ribs, spars, frames, ____ tooling is preferred because it produces best laminate quality, easier to remove parts.
____ tools for structure provide best interfaces for assembly operations.
Male tooling is ____.
female tooling is _____.
Cure for many non-structural applications temp?
Cure temp for most commercial aircraft structural application?
what does CTE stand for?
Coefficient of Thermal Expanion
3 categories for CTE?
tooling material, cure temp, tool size
Why would you want to have thermal growth?
provide additional pressure to laminate
Common practice is to closely match the tools CTE with the ___ ____ cte.
Dissimilar materials are frequently used in composite tools for
carbon fiber face sheet
tubular steel substructures
brush in working holes
in dissimilar materials, ____ ____ need to accommodate differences in thermal growth
___ ___ tools can be produced much quicker than very durable ones.
____ tools are generally most expensive.
____ tools are most durable.
what is a low cte alloy, invented in 1896?
___ _____ typically not used for aerospace composite tooling.