Electric actuator with the pneumatic valve connection
by:AIRWOLF2021-01-15
with pneumatic valves, electric actuators is applied to automatic control system.
Many different kinds of electric actuator, in the way of action in different ways, such as Angle of travel Angle to the electric actuator is the output torque, and straight travel electric actuator is the output displacement of the thrust.
Electric actuators in the system application of variety, should be selected to meet the need of pneumatic valve operation.
Pattern of connections between
a, flange connection:
this is the connection forms of pneumatic valve used most frequently.
According to the joint surface shape can be divided into the following kinds:
and smooth type: used for pneumatic valve pressure is not high.
Processing more convenient
, concave and convex type: high work pressure, can be used in hard washer
, mortise type: plastic deformation is larger washers are available, and in the corrosive medium is used more widely, the sealing effect is better.
, trapezoidal groove: with oval metal ring gasket, used to the work pressure of kg/cm2 or pneumatic valve, pneumatic valve or high temperature.
, lens type: the washer is lens shape, made of metal.
For work pressure of kg/cm2 or high pressure pneumatic valves, pneumatic valves or high temperature.
, o-ring type: this is a relatively new form of flange connection, it is with the emergence of a variety of rubber o-ring, and developed it in a sealed connection.
2, threaded connections:
this is a simple connection method, often used for small pneumatic valves.
Divides two kind of situations:
and direct seal: internal and external screw thread sealing effect directly.
In order to ensure that joint not leak, often filled with lead, cotton and ramie thread woven and ptfe teflon tape;
The ptfe teflon tape, became more and more widely used;
The corrosion resistance of the material is very good, good sealing effect, easy to use and preservation, remove, can be fully removed, it because it is a layer non-viscous film, much more superior than lead, cotton and ramie thread woven.
and indirect seal: the power of the screw tight, passed between two flat washer, gasket sealing role.
3, card sets of connection:
card set of links, connection and sealing principle of it is that when the screw nut, card sets of pressure, the blade is biting into the tube outer wall and card sets of male cone and cone closed and joint under pressure, and thus can be reliably prevent leakage.
the advantage of this type of connection is:
, small volume, light weight, simple structure, disassembling easy;
, the relay is strong, wide use, resistant to high pressure,
Kg/cm2)
, high temperature (
℃)
Shock and vibration
, can choose a variety of materials, suitable for corrosion protection;
, machining accuracy is not high;
High altitude makes the pipes easier to install.
card set of connection form, has been used in some small pneumatic valve products in China.
4, clamp connection:
this is a fast connection methods, it only need two bolts, often apply to remove the low pressure pneumatic valves.
within five, since the tight connection:
the above all kinds of connection form, all is the use of force to offset the medium pressure and sealed.
Here using medium pressure since the tight connection.
Its sealing ring with cone, with medium relative to one side with a certain Angle, within the medium pressure to the cone, and passed to the sealing ring, on the cone Angle, produce two component, a parallel to the center line of the pneumatic valve, outward pressure pneumatic valve body wall to another.
This component is the force behind.
The more the greater the medium pressure, since the tight force is big.
So this kind of connection form, suitable for high pressure pneumatic valves.
Than the flange connection, to save a lot of material and manpower, but also need a certain pre-tightening force, in order to pressure pneumatic valve is not high, the use of reliable.
Using the close sealing principle of pneumatic valves, is generally high pressure pneumatic valves.
pneumatic valve connection form also many, for example, some do not have to dismantle the small pneumatic valves, together with the pipe welding;
Some non-metallic pneumatic valve, use socket type connection, and so on.
Pneumatic valve users according to Hugh situation specific treatment.