Injection Molding Essay, Research Paper
Injection molding is a process used to form products from plastic. The process
requires a mold, clamping component, injection unit, and some sort of plastic.
As time has advanced so has injection molding by developing new techniques and
new products to aid in the manufacturing of the injection molded parts.
Injection molding was used as early as the 1860?s. It can be used to form many
different products. Whether the products are small, large, complex, or simple
they can be produced. Injection molding has derived from metal die casting.
However, the polymer can?t just be poured into a mold, it has to be forced
into the mold cavity. The polymer is forced into the mold and pressure is held
on it to avoid shrinkage in the mold cavity as it cools. Injection molding is
capable of producing a large number of parts with very high precision. All
thermoplastics except polytetraflouroethylene (PTFE), polyamides, and some
aromatic polyesters can be used by the injection molding machine. Some
thermosetting plastics can also be used. The typical fabrication process can be
done by one of two different types of injection molding equipment. Either a
plunger, or reciprocating screw type machine can be used. The process starts by
melting the polymer resin. Once the resin is melted, a mold is placed in the
clamping unit. The clamping unit is to hold the mold together. The plunger or
reciprocating screw then force the polymer resin into the mold. In the plunger
operated machine, the plunger is hydraulically operated. This forces the plastic
through a heated area, where it is then spread into a thin layer by the torpedo.
Then the melt comes to the nozzle and is injected into the mold. The
reciprocating screw rotates, this moves the polymer resin forward for injection.
As the screw rotates it acts to melt, mix, and pump the polymer to prepare it
for injection. The reciprocating screw machine is the most widely used of the
two machines. Once the polymer resin is injected into the mold cavity, the mold
is allowed to cool. The mold has a gate, which limits back flow and directs the
flow of the melt into the mold cavity. Once the mold has cooled and the polymer
has solidified the mold can be removed and the part can be ejected. When the
gate freezes, the screw begins to rotate again and the part is ejected. This
completes the cycle time. Cycle times range due to the amount of time the
polymer needs to cure or solidify. This is called the hold time. Some advantages
of injection molding are high production rates, design flexibility, low
tolerances, can process wide range of materials, low labor, little or no
finishing, and scrap is held to a minimum. However, some disadvantages are high
startup and running costs, part must be designed for effective molding, accurate
cost prediction is difficult, and machine cost is very high. The high tooling
costs come from the molds being built to a high level of precision. The molds
are usually constructed of hardened tool steel, and aluminum or other soft
metals when tooling life is not an issue. Tooling costs can range from $5,000 to
$100,000. However, there are some parts that can not be formed by any other
method of processing except injection molding. These parts typically become
feasible around 1,000 pieces. To go with the high tooling costs there are a
large number of variables that go along with it. Injection molding machines may
require special plant services that other equipment does not. As technology
advances so must the industry to keep up production. One way injection molding
is keeping up is by becoming automated. Usually, operators are placing parts
into molds, and then taking the parts out. Now, robotic devices are being used
to place inserts before molding and remove parts after molding as well as a host
of other operations as well. Not only does the robotics speed up the process,
but makes it much more cost effective. Another way industry is trying to keep up
with technology is by using computer software. The software is called ?Mold
Adviser,? which is a mold design and analysis package that can be used to help
speed up operations while reducing tooling costs. Using the past standard
operation of designing molds a company could easily waste six to twelve weeks
and anywhere from $30,000 to $40,000 on fixing a mold that has a problem with
filling correctly. The new software will detect these problems up front before
production begins. It is used with a CAD program, and is really divided into two
parts. The Part Advisor and the Mold Advisor. The Part Advisor can test the
parts design and analyze the part to see if it will fill correctly. Once the
part has been analyzed, users begin the Mold Advisor. The Mold Advisor will help
setup gates and runner systems, predict plastic flow, shot size, and cycle time.
Users of the new software have reported that the software is easily learned and
user friendly. Injection molded products include TV, VCR, CD?s, CD players and
computer housings. So, one can see the impact that the products of injection
molding have on our every day life. Injection molding has been used since the
1860?s. Products of all sizes and shape have been produced. However, with
advancing technology and the high cost of molds it will be interesting to see
how much further injection molding will advance and how it will advance in the
future.
Harris, Laura. ?Injection Molding.? 30 Nov 1999. engr.uconn.edu/cheg/polymer/injmold.htm
?Injection Molding.? 30 Nov 1999. endura/injmold.htm
Mapleston, Peter. ?New approaches show promise in large-part molding.?
Modern Plastics Nov 1999. Snyder, Merle R. ?Automation is gaining in vertical
infection molding machine market.? Modern Plastics Aug 1996. Taylor, Gerry.
?One-two punch knocks out injection-molding problems. Machine Design 17 June
1999: 80.
Другие работы по теме:
Death Penalty Essay Research Paper Once upon
Death Penalty Essay, Research Paper Once upon a time, there was a man who sacrificed for a country by going to a war. Years later, when the war was over, luckily the man came home alive, but he wasn?t mentally well. Time past. He started getting confused between his real life and the life during the war. Finally, he committed a murder, while thinking that he was still at war.
Capital Punishment Its Ineptitude And Faults Essay
, Research Paper The death penalty is not an effective solution to any of society s criminal problems and a cruel, inappropriate punishment. It is a simple-minded solution to a complex problem. People are under the impression that it is acceptable to just throw away a human life similar to garbage. We are living in a generation of the disposable human being.
Thou Shall Not Kill Essay Research Paper
Capital punishment is the killing of a killer. The act of capital punishment is wrong and useless and I have few reasons why. When a murderer is executed or shot by lethal injection it costs almost twice as much as a
Calf Implants And Synthol Essay Research Paper
Implants and Synthol Injections The article I read was entitled “Fooling Mother Nature”. It was found in the April 2001 issue of MuscleMag International. The article revealed some of the latest techniques that modern bodybuilders have been using when steroids just are not enough. The two techniques mentioned are calf implants and the sight injection of an oil called Synthol.
Execution Essay Research Paper There are different
Execution Essay, Research Paper There are different kinds of executions for those that are guilty of murder. In the United States the death penalty is authorized by hanging, electrocution, gas chamber, firing squad, or lethal injection. Most other nations use hanging, firing squad and stoning. These executions have been done to those that are on death row.
Epoxy Resins Essay Research Paper The group
Epoxy Resins Essay, Research Paper The group of synthetic resins called epoxies produce the strongest adhesives in current use, as well as plastics and corrosion-resistant coatings. Epoxy
The Death Penalty Essay Research Paper Death
The Death Penalty Essay, Research Paper Death penalty brutalizes us. Every human being deserves the dignity of life. This includes the most brutal of murderers and insane killers. Premeditated,
Capital Punishment Essay Research Paper I have
Capital Punishment Essay, Research Paper I have an opinion on many subjects. Whether or not you agree with it is your opininon. This country, being a free country, gives me the right to persuade you to see things my way. This is my goal with the following essay.
Capital Punishment Essay Research Paper Capital PunishmentElectrocution
Capital Punishment Essay, Research Paper Capital Punishment Electrocution . . . gas chamber . . . lethal injection . . . field shooting . . . all are forms of the death penalty used across the United States. Some believe that when one person takes the life of another, that person’s life should be taken as well.
The Death Penalty Essay Research Paper Each
The Death Penalty Essay, Research Paper Each year there are about 250 people added to death row and 35 executed. From 1976 to 1995 there were a total of 314 people put to death in the U.S. 179 of them were put to death using lethal injection, 123 were put to death using electrocution, 9 were put to death in a gas chamber, 2 were hanged, and 1 was put to death using the firing squad.
Euthanasia 11 Essay Research Paper In this
Euthanasia 11 Essay, Research Paper In this literary work by James Rachels, the author is fighting to make his opinion believed, rather than give an unbiased article. He is arguing about the differences between active and passive euthanasia. The author makes references to several stories to try and sway the reader to believe that the best thing to do in cases where people want to die, is to go ahead and perform assisted suicide.
Nu Wa Essay Research Paper
“Creator of Man-Kind” In the beginning, the earth was nothing but a huge, dark, and empty piece of rock. Then an egg cracked, out came the God that separated the earth from heaven. From the “God” (Pan Ku), came lots of other deities that helped create earth as a whole. One of the deities was Nu Wa. Nu Wa’s life was told in three stories; “Nu Wa Creates Humanity”, “The Marriage of Nu Wa and Fu Xi”, and “Nu Wa Mends the Sky.” From the readings, Nu Wa plays different roles.
The Analysis Of
“Ode To The West Wind” Essay, Research Paper Mr. Jackson, seeing as you have been found guilty of murder in the first degree by the citizens of the Great Republic Of Texas, I have no choice but to sentence you to death by means of lethal injection, to be administered by a state-appointed prison medical technician within 90 days’ time.
Impotency New Therapy Essay Research Paper
Impotency: New Therapy By Tony Gramazio As many as two-thirds of the men with impotency because of physical conditions, vascular disease, stress, trauma, surgery and diabetes, can probably
Effect Of Blocking Cavities Experiment Essay Research
Paper Jared Matola Section 002 Team Members:Sam LiptakMatt Sudak Conducted: 2/10/99 Due: 2/17/99 Turned in: 2/17/99 at 8:00 Summary of Results: The purpose of this experiment was to demonstrate the effect that blocking cavities has in an injection mold on the process window and part quality. First we had to get a 95% full part.
Othello Essay Research Paper Honesty is one
Othello Essay, Research Paper Honesty is one of the most important factors in Othello. Although there is very little honesty in the play the term is most commonly put to Iago, who also happens to be the most dishonest character in Othello. Due partly to the other characters naivet , Iago is capable of manipulating, brainwashing, and molding the other characters to satisfy his need for revenge against Othello.
Death Penatly Essay Research Paper There are
Death Penatly Essay, Research Paper There are curretnly five authorized methods of execution in the United States. They are lethal injuction, electrocution, hanging, firing squad and lethal gas. The most common is lethal injection, followed by electrocution and then lethal gas, with only two states utilizing hanging and the firing squad.
Capital Punishment By Lethal Inject Essay Research
Paper The process of execution by lethal injection involves a carefully organized program. As it is stated in the article My Friend s Execution by William Vance Trollinger Jr. the process of execution is divided in a number of steps. First, two days before the execution, the prisoner is moved into the death cell, which is located in the depths of the prison.
Legalizing Euthanasia Essay Research Paper Legalizing euthanasia
Legalizing Euthanasia Essay, Research Paper Legalizing euthanasia in the United States gives rights to the people. Rights to those who endure the irrefutable agony of pain and suffering, rights to those who want to be cured of their pain, and rights to those that struggle to end their suffering. Euthanasia is the answer to end their suffering.
Death Penalty Essay Research Paper Is the
Death Penalty Essay, Research Paper Is the Death Penalty Right or Wrong? Should we be able to execute people that have been convicted of murder or should we give them a chance to break out of jail and maybe kill other people. Well the Death Penalty has been around for a while ever since the Old West use to hang people for punishment.
Capital Punishment Essay Research Paper Capital PunishmentDoes
Capital Punishment Essay, Research Paper Capital Punishment Does capital punishment really help? Many people say that it lowers the murder rate man many think it is cruel to take some ones life. The statistics do not show a decrease in murders where capital punishment is in place. Should the penalty be abolished if it is not helping? Is this penalty effective in putting the real murderers at justice.
Theatre Comedy Essay Research Paper Electrocution is
Theatre Comedy Essay, Research Paper Electrocution is the Only Way Regardless of how barbaric it may be, the electric chair should remain the source of execution used by the state of Florida. It has served as a valid execution tool for the
Music Today Just A Bunch Of
Garbage? Essay, Research Paper It’s 4:00 pm and you just got home from school. You turn on the radio only to hear some media generated stuff banded together by some lame drum beats. This is unfortunetly, the music of today.
Pros And Cons Of Death Penalty Essay
, Research Paper Texas is known for many things, both socially and politically. The death penalty is a very serious issue that we as Texans need to concentrate on in the upcoming election. The Death Penalty has been around forever even back into the dark ages. It is the way that we punish people for crimes they have been convicted of or have confessed.
Capitol Punishment Essay Research Paper Capital PunishmentOne
Capitol Punishment Essay, Research Paper Capital Punishment One of the biggest debates in America in the past century has been the debate on capital punishment. Many people feel that it should be an eye for an eye, that if a person wants to kill another person, that person deserves to die for the crime they have committed.
Capital Punishment And Religion Essay Research Paper
Capital Punishment Electrocution . . . gas chamber . . . lethal injection . . . field shooting . . . all are forms of the death penalty used across the United States. Some believe that when one person takes the life of another, that
Polystyrene Bead Molding Essay Research Paper IntroductionOn
Polystyrene Bead Molding Essay, Research Paper Introduction On September 7th and 14th of 2000 my lab partners and I conducted the polystyrene bead molding project. My lab partners are Josh Dick, Mike Ward, and Keith Matlock, and we conducted the procedure in room W126 of the Kansas Technology Center. We were to attempt to make polystyrene bead molds using two different methods.
The Social And Cultural Factor Essay Research
Paper James Hartmann 10/22/00 Midterm Exam History 337 The Social and Cultural Factors of Modern Sports When we observe modern sports and see the progress it has made, we can t help but to look at the factors in the past that shaped sports, which has shaped our culture much in the same way. Urbanization, for example, affected organized sports much like it affected our culture.
Heroin Injection Essay Research Paper I choose
Heroin Injection Essay, Research Paper I choose the article ?Heroin injection among addicted felons.? In this article, the authors researched a total of five hypotheses. However, I decided to focus on the social network hypothesis, which states that white heroin users are more likely than black and Hispanic users to adopt the method of injection.
Is Euthanasia Ethical Essay Research Paper Is
Is Euthanasia Ethical Essay, Research Paper Is Euthanasia Ethical? Euthanasia Comes from the Greek word meaning the good death. It is defined as The act or practicing the end of life of an individual suffering from a terminal illness or an incurable condition, as by lethal injection or the suspension of extraordinary medical treatment.
Death Sentence Essay Research Paper Almost 90
Death Sentence Essay, Research Paper Almost 90 percent of all convicted killers who are released, kill again. I think that all states should have a mandatory death sentence for certain crimes. It was accepted in the past, but recently certain states have decided against it.
The Battle Of Midway Essay Research Paper
I am doing a report on the disease Diphtheria. The definition of the disease is a bacterial disease that affects the throat and can cause serious or fatal complications. It is a serious disease caused by the