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Showing posts with label Working Principle. Show all posts
Showing posts with label Working Principle. Show all posts

Wednesday, 21 January 2015

Ribbon Blender - Plastic Process Equipment

RIBBON BLENDER

RIBBON BLENDERScope of Application: 
In the U shape container, there are positive and negative ribbons. Special proportion of the two ribbons can be rectified with the kind of material, quantity and the proportion of body. The ribbon blender has good effect on mixing viscosity or cohesion powder.
Characteristic: 
A, Fast mixing speed can satisfy the rigorous demand of mixing the materials with different physical property.
B, The rotation is under critical speed, which will reduce the effect of fragmentation to the material(e. G. Crystal particle)
C, Lower height of the container is convenient for installation.
D, The positive and negative ribbons are set up at he same level, forming a mixing environment of low power but high efficiency.
Ribbon BlenderWorking Principle: 
A, The horizontal axes make the materials move up and down.
B, The outer ribbon gathering the material from sides to center and the inner ribbon pushing the material from center to sides.
C, Every screw makes the materials do axial and radial movement, the materials do relative cyclical movement so to gain the intensive mixings ends.
Seal: 
Our company provides various sealing devices according to difference of materials. The normal sealing structure is stuff seal and also called TEFLON seal. After using for a period, user(s) should fasten and enhance it. However, the dynamic seal has a long-time sealing effect and is especially fit for the powder, liquid.
Feeding inlet on the body cover: 
Two types:
A, used in the whole mixing/ blending process: In order to connect the feeding device, we design the connecting mouth
B, used in the manual feeding: In order to operate and clean inside of the body, we design feeding inlet(s) or door(s).
Discharging:
There is a discharging valve at the bottom of mixer body. When mixing different types of materials, we use flat discharging valve. The operation of the discharging valve should be convenient and there are three types: Manual, air driven and electricity driven. The manual discharging is operated on the valve and the open extent is controlled by hand freely. The air driven discharging valve, assembled with cylinder, work under the air pressure. The electricity driven discharging valve works under control of electricity control box.
Temperature control: 
We can use a jacket when heating, cooling or heat-preservation is needed.
The jacket is filled by circulation and heat conduction medium and can not bear high pressure. There are two kinds of heat conduction medium: Water and oil. The water temperature should be limited in 90 and the oil temperature should be limited in 300. The jacket coordinates the external heating system, the expulsion system, the pipeline to carry on to the material continues and even temperature processing.

Saturday, 25 October 2014

Plate and Frame Heat Exchanger

PLATE & FRAME



Typically, plate and frame heat exchangers are used for liquid-liquid exchange at low to medium pressures. However, gasket-free plate and frame heat exchangers can safely operate at high temperatures and pressures. Plate and frame heat exchangers offer flexibility because plates can be either added or compressed for each different situation.

Plate and Frame Heat Exchanger
Plate and Frame Heat Exchanger
Plate and Frame Heat Exchanger
Plate and Frame Heat Exchanger

GENERAL INFORMATION

The gaps between the plates in plate and frame heat exchangers can be adjusted according to the degree of fouling (deposits, corrosion, etc.) that is expected.
Plates of Plate and Frame Heat Exchanger
Plates of Plate and Frame Heat Exchanger



The counter-current flow of fluids that occurs in plate and frame heat exchangers allows approach temperatures as low as 1 to 2°F.

Plate and Frame Heat Exchanger

Gaskets ensure that the cold fluid (blue) and the hot fluid (red) don't mix. Alternatives to the traditional gasket seal include brazing and laser-welding.


Plate and Frame Heat Exchanger

The plates are stacked in an alternating manner to cause the counter current flow. The diagram below shows the flow in a heat exchanger. The design allows for the two media to flow in alternate directions and not be mixed. However, heat can be transferred from one medium to the other through the plates. 

ADVANTAGES

DISADVANTAGES

  • Require less space and are less expensive than shell and tube heat exchangers.
  • Easy to adjust for different liquids by adding or subtracting plates.
  • Pressure can be varied by compressing the plates.
  • One frame can be used for multiple duties by simply changing plates.
  • Working temperatures up to 550°C and pressures of 780 psi are possible with gasket-free versions.
  • High heat transfer coefficients relative to shell and tube heat exchangers.
  • Up to ten times more resistant to fouling than shell and tube heat exchangers.
  • Gasketed plate and frame heat exchangers have a maximum operating condition of 149°C and 300 psi.
  • Not good for vaporizing fluids or large amounts of vapor.
  • Gasket-free versions are impossible to open for inspection or cleaning.