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The clamping units are: (1) mechanical toggle clamp and (2) hydraulic. In addition, there are hydromechanical units which combine hydraulic and mechanical actuations.
What is the clamping unit?
The clamping units are used to keep the mold shut against the forces developed when injection pressure pushes plastic into the closed mold. Therefore, the amount of clamp force must be at least equal to the amount of injection force. The machine sizes are determined by the clamping tonnage forces.
How many types of clamping systems are there?
There are three types of direct hydraulic two-platen clamping system: non-circulation, external circulation and internal circulation [5].
What are the function of clamping device?
A clamp is a fastening device used to hold or secure objects tightly together to prevent movement or separation through the application of inward pressure.
What is the unit of clamping force?
Clamping force is the force exerted by the clamping unit of an injection molding machine on the mold. The clamping force is also known as clamping tonnage because the force is measured in tons. The injection molding machine of 200 tons can exert 200 tons of clamping force.
Which is the best injection moulding machine?
Top five injection moulding machine manufacturers ARBURG. Having created its first injection moulding machine in the fifties, Arburg is one of the most established injection moulding machine manufacturers in the market. ENGEL. Haitian International. Sumitomo Demag. Husky Injection Molding Systems.
How do you calculate clamping force?
Mold Clamping Force Formula (F: tf) The total projection area is the total of the projected areas of the cavities and runners in relation to the parting surface. Therefore, this value varies depending on the number of items molded and on the runner layout. 400 × (16.0 + 5.0) ÷ 1000 = 8.4 (tf).
What is hydraulic clamping system?
The hydraulic clamping is the pipe gripping done through by clamps which execute the opening movement and closing hydraulic pressure mode, unlike standard machines where all these movements are manually done. This is one of the most popular features of large diameter welding machines such as TracStar, mMegaMc.
What is the principle of clamping?
Strength: The clamping system should be capable to hold the workpiece securely against the forces developed during operation. Clamping device should be capable to be unaffected by the vibrations generated during an operation. The clamping force should not dent or damage the workpiece with excessive pressure.
What is a good clamping force?
We recommend a 2-to-1 safety factor (2580 lbs). Even though FL (the combined force from all clamps on the left side) equals zero, a small clamping force may be desirable to prevent vibration. Too much clamping force can be as bad as too little. Excess force can cause fixture and machine-table distortion or even damage.
What is hydromechanical clamping unit?
The Hydrodock clamping system is used as the clamping system for the machine tool interfacing with changing processing units. For example, these include milling heads and attachment spindles. Therefore, no permanent pressure is required following the clamping process.
What are the types of clamping?
What are the different types of clamps? Screw Clamps. Screw clamps are types which use a screw mechanism to adjust the jaws and clamp a workpiece in place. Quick-Release Clamps. Bar Clamps. Locking Clamps. Angle Clamps. Flooring Clamps. Band Clamps. Toggle Clamps.
What clamping means?
1 : a device designed to bind or constrict or to press two or more parts together so as to hold them firmly. 2 : any of various instruments or appliances having parts brought together for holding or compressing something. clamp. verb. clamped; clamping; clamps.
How do you calculate shot capacity?
Multiply machine shot by 1.4 if maximum injection screw stroke is greater than or equal to four. For example, if machine shot is 200 grams and maximum injection screw stroke is four, the result is 280. Divide the result by the melt density for polystyrene. For example, 280 divided by 100 grams is 2.8.
What are the two basic types of clamping units?
What are the two basic types of clamping units? The clamping units are: (1) mechanical toggle clamp and (2) hydraulic. In addition, there are hydromechanical units which combine hydraulic and mechanical actuations.
What is shot weight?
The main factor that determines the material thickness is the amount of plastic that is used during the manufacturing process. The amount of poly used to manufacture a tank is called the shot weight. The greater the shot weight, the thicker the wall of your tank will be.
What are the main parts of a clamping unit?
The components include: Clamping system. Machine ejectors. Moveable platen. Stationary platen. Tie bars.
What are the requirements of clamping system?
Basic requirement of clamping devices The clamps must hold the workpiece rigidly while machining against all disturbing forces acting on the workpiece. The clamping should not damage workpiece while holding them. The clamping should be applied only where the workpiece has enough support of the fixture body.
How do you calculate shot weight?
Let’s assume we have a shot weight of 40.6 gms. Thus, we can calculate volume as mass/density, which will be (40.6/1.52)= 26.71 cube centimeters. To calculate the injection stroke or shot size, we can put all values in the formula of shot volume, i.e., Shot Volume = π x r2 x Shot Size.
How do you know what clamping force you need?
The required clamping force can be calculated from the cavity pressure inside the mold and the shot projected area, on which this pressure is acting. There are variables that affect the clamping force calculation, like the material type (low-flow versus high-flow plastic), and the depth of the part.
What are parts of injection?
The injection is similar to an extruder. It contains a barrel that a hopper with a supply of plastic pellets feeds from one end. Inside the barrel is a screw that turns to mix and heat the polymer. The screw also acts as a ram that quickly moves forward to inject molten plastic into the mold.
