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Design for Die casting manufacturing

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Design guideline

  • Similar to injection moulding. Consider die casting when the inserted part does not have sufficient strength.
  • Wall thickness function of alloy (typ 1.0 – 3mm). can go up to 10mm (will be permeable –a power not proportional to the wall)
  • Ribs 80% wall thickness shrinkage less of an issue.
  • Cooling time proportional to wall thickness (injection is t^2), so can have faster cycle times and thicker walls.
  • Draft depends on alloy. Assume > 1.0 deg, esp. on cavity side.
  • Tolerance is a function of alloy, part geometry and dies construction.
  • Zinc alloy linear: + / − 0.025mm across up to 50mm.
  • Zinc alloy hole: + / − 0.015mm up to 25mm diameter.
  • need over flow wells and secondary ops − > $$
  • No internal slides or snap fits.

The die casting option: broad range

  • Agriculture machinery
  • Auto motive vehicle
  • Building hardware
  • Electrical and electronic equipment
  • Hand tools
  • Home appliances
  • Industrial product
  • Instrumentation
  • Lawn and garden equipment
  • Office furniture
  • Recreational equipment
  • Portable power tools

Cold chamber

  1. Advantages
  2. Large complex parts
  3. Higher pressure
  4. Many production layouts possible

Hot chamber Die casting

  1. Advantages
  2. Metal temperature control.
  3. Automatic refill
  4. No cooling
  5. Less oxidation

Types of dies

  • Single cavity die
  • Multiple cavity die
  • Family die
  • Unit die

Injection sizing

  • Critical variables
  • Hydraulic pressure
  • Cylinder size
  • Dry shot speed
  • Gate area
  • Part volume
  • Fill rate

Clamping tonnage

  • Projected area of shot X metal pressure
  • Metal pressure   ͏͏͏͏̴ 10,000 psi (70 MPa)
  • Example
  • 100 ꭗ 10000/2000=500t (450mt) of clamping force required

Other process design concerns

  • Filling pattern and plunger speed profile
  • Venting and vacuum
  • Thermal control
  • Dimensional control

Thixocasting (semi – solid)

  • Most casting processes use a fully liquid feed material
  • Semi – solid casting uses as feed material that is 50% liquid and 50% solid

Semi – solid metal casting

    Advantages

  • Viscous  flow (less air trapped)
  • Shorter cycle time (colder material)
  • Increased tool life (less shock)
  • Reduced shrinkage (narrower cooling range)
  • Reduced porosity (directional solidification)
  • Improved mechanical properties

Example part

  • Turbocharger impeller

Squeeze casting

  • Fully liquid feel metal
  • Inject slowly
  • Avoid turbulence associated with conventional de casting

Processes

  • Horizontal (HSC)
  • Horizontal vertical (HVSC)
  • Vertical (VSC)

Squeeze casting

  • Process specific advantages
  • Non – turbulent flow
  • Reduced porosity (directional solidification)
  • Improved mechanical properties
  • Process specific disadvantages
  • Casting wall thickness Min 4 to 5mm (0.150 to 0.200”)
  • Large gates 6mm to 38mm (0.25 to 1.5”)
  • Large runners
  • Directional solidification (gate location)
  • Limited cavity number (orientation in die, pressure opening die)

High integrity die casting processes

Vacuum Die casting

  • Fully liquid feed
  • Fast fill
  • Vacuum level in the die cavity of 100 millibar or less
  • Eliminates cavity gasses from the shot sleeve and die
  • Used for crash resistant automotive castings

Metal Die Casting and Metal Foundries

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Is Metal Casting the “Most Fundamental” Industry?

On the North American Die Casting Association’s website, the association says that metal die casting is America’s most fundamental industry. Is this true? Should you take a metalworking association’s word for that kind of statement? I think it’s impossible to evaluate one sector of the economy as “most fundamental,” but they’re certainly right that metal casting is an extremely important industry.

What I’ve found in the time that I’ve been writing about industry is that different disciplines and industrial sectors are inseparable from one another. The computer industry and the casting industry, for example, are codependent. The computer industry needs casting companies to make heat sinks and other vital computer components, and the casting industry needs the computer industry to manufacture hardware that can manage its CNC manufacturing processes. Think of any example of a sector in industry and I guarantee that you’ll find at least one other sector that it is codependent with.

Die casting companies are no exception to this rule. The low hanging example fruit, when it comes to die casting, is, again, the computer industry. Many computers involve at least one die cast part, and die casting operations are often managed by CNC hardware and software, which the computer industry produces. But there are many other examples as well. Die cast parts are involved in the equipment that is used to extract raw metal, and that raw metal can then be used to make more die castings. There are many other examples.metal die casting

Die casting is an excellent example of the codependence and interdependence of industrial sectors. Even though the NADCA insists that metal casting is the most fundamental industry, bear in mind that no industrial sector could exist without depending on other sectors. This is the reality of a developed, industrial economy.

Metal Foundries: A Look Inside

A metal foundry is a place where metal is transformed from its base material into useable ingots that can be transformed into usable metal pieces. Some foundries shape their own metal pieces, while others ship the finished metal off to other factories for further processing.

There are a variety of different metals that can be used to create metal casting and shapes. Usually, aluminum and iron are used, but other metals, like bronze, steel, copper, tin, magnesium, and zinc are also processed in a factory and shaped into parts using metal casting. Most metal foundries use a special kind of metal casting to create ingots or other metal shapes for further processing. A metal foundry typically uses a multi-step process to finish the metal pieces.

First the metal is melted in a large container and any impurities are removed. If the metal will be a combination of metals, they are added at this point and mixed together. Most foundries use a furnace to melt the metal. After melting, some metals require degassing. Degassing is the process of removing hydrogen in the metal. Too much hydrogen produces a porous metal that has little use. Degassing is done by bubbling nitrogen or argon into the metal while it is still in liquid form.

After melting and degassing, the metal is poured into a mold. Different foundries will have different molds available, such as ceramic molds, sand molds, investment casting, die casting, billet casting, or lost-foam casting. Usually the metal is poured into the molds using robotic pouring systems.

The metal is allowed to cool, then removed from the mold. The metal piece then goes through a degating or deburring process, which removes unwanted pieces from the mold. The metal piece then may be heat treated to give it extra strength, or simply cleaned and polished for final use.

Aluminum Patio Furniture

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There are two kinds of aluminum patio furniture- cushioned and non-cushioned. There are available designs which do not need to have cushions to feel comfortable when seated on. However, if your outdoor furniture needs cushioning, it is imperative that you select the right outdoor cushions. Since they will be exposed to extreme sunlight and moisture the entire day, the cushions must be made from sturdy and water- resistant fabric, which does not fade easily. There is a vast selection of designs and styles to choose from, as well as various patterns and colors to suit the overall exterior theme of your home sweet home.

It is therefore concluded that cast aluminum patio furniture will stand on your outdoor for several seasons to come- from winter and spring to summer and fall. They are designed to stand the test of time and make your family bonding times better and better. Spend ample time for taking a close look at the available options coming before you. The quality of a product should always top your list of considerations. Make sure that this investment will be something suitable for the specific lifestyle of your family.

Patio furniture made from this aluminum die casting element will neither fade nor rust. Therefore, you can keep them outdoors without any worry. Moreover, this aluminum is generally coated with powder paint particles which are bonded with the metal by means of a heating process to prevent the material from scratching, chipping and any other signs of wear. The durability of this material is one of the primary reasons why plenty of furniture makers, including the renowned ones, choose it. Rest assured that furniture pieces made from it possess extraordinary strength.

As a buyer, you can also have numerous options when it comes to color, style and design. If you want your patio to look simple, there are minimalist aluminum pieces of furniture available today. On the other hand, if you desire an elaborate outdoor space, there are elegant and intricate designs and styles to choose from. Aside from visiting a local furniture store, another way of finding these kinds of furniture is by shopping online.

In fact, this method will save you some bucks, because most of these products are available at reasonably lower prices. There are also online retail furniture stores that do not charge high shipping fees.

 

 

When to Use Die Casting

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Metal Casters have the luxury of choosing between several casting methods to accomplish their goals. Often times the metal caster chooses one method and sticks with it for several years until need directs him to another. Of course, there are those adventurous few who like to sample each casting method to find the best fit. Sure, sand casting might be the most popular but what about Lost Foam or Investment?

What about Die casting?


Die casting is used by industrial foundries and manufacturers to create practically anything and everything, such as die cast cars. Many small foundries, like the one in your garage, backyard, of workshop may find that die casting is really just not economical. But who said that having fun and trying new things was ever economical? This process we aslo called high pressure die casting or pressure die casting, The process of Die Casting involves a simple concept. The molten metal is injected with high pressure into the mold or mold cavities. The mold used in die casting can have several small civilities of either the same pattern or different pattern.


The name Die Casting comes from the molds which are called dies. These molds are reusable and are often made from steel but other alloys can be used as long as they can withstand high pressure. The reason dies must be created from metal and not from sand or other material is due to the high amount of pressure used to get the molten metal into the mold. If sand molds were used in a Die casting procedure then the mold would crumble. There are plenty of advantages of using dies in a casting procedure which makes this method desirable for anyone wishing to create a high volume of similar castings.

Die casting is perfect for anyone that needs to make a lot of the same thing without any quality or pattern deviation. This is especially helpful in certain industries where quantity and quality count. Many hobbyists may have no use for die casting on a practical basis but will often try at least one Die casting for the sake of trying.

There are two types of machines used in the Die Cast procedure. These machines are essentially the same and are called the Hot-chamber and the Cold-chamber.

The Hot-chamber machine melts the alloy and feeds it into a section of the machine referred to as the gooseneck. A piston then forces the alloy into the mold. A separate furnace is not needed but the draw back of this is that metals with higher melting points can not be used.



The Cold-chamber is used for metals that can not be used by the Hot-chamber such as aluminum and copper. A separate furnace is needed to melt the alloy which is then poured into the injection cylinder and then shot into the mold.

The advantages of using Die casting vary but the most noticeable advantages are the repeated quality, smooth casting surface, and the quick production of casts. While the initial cost of Die Casting exceeds several of the other casting procedures, those that need a high number of casts in the shortest amount of time possibly will benefit greatly from the investment.

Die casting is commonly used to create commercial goods as it yields a high volume. The molds, or dies, used vary in life cycle depending upon the material used to create the die. The die can have one cavity or several cavities depending upon the need.

Everyone should try Aluminum die casting, magneium die casting or zinc die casting at least once if they can afford the initial cost. Besides, who knows when you’ll need a small battalion of metal soldiers which can be made quickly and easily with die casting.

Metal Casting

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Charlie Chan arrives in Shanghai at the behest of the U.S. government to help stop an opium smuggling ring. He receives a warning aboard ship not to stop in Shanghai. He is met by his Number One Son, Lee Chan, as well as Philip Nash and his fiance, Diana Woodland. Charlie is the guest of honor at a banquet held that evening, hosted by Sir Stanley Woodland (David Torrence in an uncredited role). When Sir Stanley opens a box to give a handwritten scroll to Charlie, he is shot and killed by a gun inside the booby-trapped box. Charlie meets with Colonel Watkins, the commissioner of police, and agrees to investigate the crime. The next day, American FBI man James Andrews arrives in Shanghai, accompanied by his valet, Forrest (Gladden James in an uncredited role). That night, an assassin shoots what seems to be a sleeping Charlie Chan in bed. But Charlie, suspecting another attempt on his life, rigged a dummy and escaped death.
Watkins, Nash, and Woodland try to meet with Andrews. Nash sneaks off and goes through Andrews’ briefcase, suitcase, and other papers. Charlie arrives, and while he is speaking with Andrews is nearly shot. Charlie and Andrews managed to retrieve the gun, but the assassin escaped. A fingerprint on the gun reveals that Nash is the likely suspect, and he is arrested. A letter Nash had stolen from Andrews’ things seem innocuous, but Charlie takes it as evidence. Charlie returns to his hotel and meets with Lee. They receive a note from Col. Watkins asking them to come to an office downtown. They check with police headquarters, which assures them the note is genuine. Charlie goes, but Lee realizes the note is fake when Col. Watkins calls soon thereafter. Charlie is kidnapped and taken into a room to meet with a mysterious Russian (Ivan Marloff). Lee tries to save his father, but is caught. The two bluff their way out of danger, and after a brief fight manage to escape.

Metal Die Casting

That evening, Charlie and Andrews meet with Col. Watkins. Diana Woodland arrives and asks to see Nash; her request is granted. But Diana sneaks Nash a pistol, and the two escape. Later that day, Andrews and Charlie return to the house where Charlie was held. The gang has left, but Charlie finds an ink pad in the fireplace and takes it as evidence. Lee shows up dressed as a beggar, and Charlie sends him home. Oddly, Charlie arrives at the hotel first. Lee shows up later, and reveals that he saw their kidnapper in a taxi on the street and followed him to the Cafe Versailles. Moments later, Andrews calls and summons Charlie to his apartment. Before he leaves, Charlie sends Lee off on a secret mission. Charlie arrives at Andrews’ apartment, where the FBI agent has caught a gangster involved with the Marloff gang. After a punch to the jaw, the gangster reveals that the Cafe Versailles is where the opium gang is hiding out. Andrews calls the police, and asks them to meet them at the club. Charlie and Andrews leave for Cafe Versailles. After Charlie and Andrews depart, Andrews’ valet, Forrest, frees the gangster and the two leave. At the club, Nash (disguised as an able seaman) sees some of the Marloff gang heading toward the basement and follows, but is captured. Charlie and Andrews arrive moments later, and follow a gang member into the basement as well. The basement is where opium is being shipped out via riverboat, reached by a trap door. Andrews urges Charlie to go first, but Charlie hesitates when his flashlight mysteriously refuses to work. The police arrive by boat, and after a brief shootout capture the gang.
Charlie surprises everyone by arresting James Andrews. Lee Chan reveals that his father sent him off to cable America, and he has just received a reply which indicates that the real Agent Andrews was murdered in San Francisco three weeks earlier. The false “James Andrews” is really the leader of the Marloff gang, and intended to have the gang murder Charlie in a shoot-out when they descended through the trap door. Charlie knew Andrews did not really call the police, and had Lee summon them instead. Nash’s escape from police custody was planned by Charlie. Charlie reveals that Forrest used the ink pad to put Nash’s thumbprint on the revolver to frame him. Nash is declared innocent, and Andrews and Forrest go to jail. External links
Charlie Chan in Shanghai at the Internet Movie Database