CN211727440U - Simplified vacuum suction casting process program control electric loop - Google Patents

Abstract

The vacuum suction casting upper chamber is descended and the pressing procedure is combined to reduce one loop. In the casting production of high-alloy heat-resistant steel thin-wall castings, when the supercharger volute of the thin-wall castings is filled with mold in the casting of high-alloy heat-resistant steel with poor fluidity, qualified products cannot be obtained by gravity casting, and then vacuum suction casting is adopted, so that the production requirements can be met, but the control program of a used suction casting chamber is as follows: the upper chamber descends → closes the chamber and seals → compresses tightly → opens the vacuum → time delay → stops the vacuum to open the atmosphere → pine type → the upper chamber rises this series of procedures, in use some link very easily takes place, control point and cylinder valve's sealing member receive high temperature gas leakage, joint ageing etc. make the maintenance complicated, often there are few fault points to influence the phenomenon of procedure to take place, now merge some control procedures, reduce control point and carry out the cylinder to the procedure simplification processing, the reduction of trouble makes the availability factor very improve.

Description

Simplified vacuum suction casting process program control electric loop

Technical Field

The electric loop control program of the vacuum suction casting process is further combined and simplified.

Background

The high-nickel alloy heat-resistant steel turbocharger turbine shell accepted by the company has a wall thickness of only 2.5 mm. The fluidity of the steel casting in the molten state is extremely poor, and the thin-wall mold filling is a technical problem. From 2015, the company tries for antigravity casting process trial production, and after more than three years of exploration, in 2018, an antigravity casting production line with a vacuum suction casting chamber as the center, an upstream matched core-setting conveying line and a downstream matched sand-cleaning polishing conveying line are built.

The electric control programs of the suction casting chamber are respectively as follows: the suction casting upper chamber descends → the chamber is sealed → the pressure mold → the vacuum is opened → the time delay → the vacuum is stopped to open the atmosphere → the loose mold → the upper chamber is loose → the upper chamber ascends.

The pressure relay, the displacement relay, the time relay, the temperature relay and other signaling instruments are adopted to control the action of the intermediate relay, so that the electromagnet drives the valve core to change direction, and the actions of the cylinders such as sealing of the suction casting chamber, compression molding, lifting of the suction casting chamber and the like are controlled.

When in use, a plurality of cylinders, electromagnetic directional valves, relay contacts and various sealing elements are failed and leak due to high temperature of the environment, so that a plurality of fault points are caused, the maintenance workload is large, such as cylinder groups sealed by suction casting chambers and compression type cylinder groups, and particularly, as long as one link fails, the whole process stops running and waits for maintenance.

Disclosure of Invention

The invention aims to combine programs as much as possible and act simultaneously, thereby reducing the use of a signal sending device, simplifying the control link, reducing the use of various relays and leading the process connection to be more compact and reasonable.

The technical scheme is that on the basis of fully observing the site, the main key point is that when vacuum suction casting is carried out, a sand mold and a suction casting chamber can be sealed, so that the negative pressure efficiency is not damaged. The electric control program of the suction casting chamber is as follows: descending the suction casting upper chamber (compacting the sand mold) → opening vacuum (compacting the suction casting upper chamber) → delaying → stopping vacuum and opening atmosphere (loosening the pressure and loosening the upper chamber, and ascending the suction casting chamber). Firstly, the sand mold is mounted in place to send a signal, the suction casting upper chamber descends, the profiling cylinder also descends, the profiling plate simultaneously compresses the sand mold in the descending process, the self weight and the descending pressure of the suction casting upper chamber are greater than the profiling pressure, and the profiling pressure cannot be interfered. When the upper chamber descends to a proper position, the pressure relay sends a signal to open the vacuum valve for suction casting, meanwhile, the suction casting upper chamber is also compressed by the atmosphere and sealed with the outside, when the set time for suction casting is up, the vacuum valve is closed and the atmosphere is communicated, the suction casting upper chamber is lifted, meanwhile, the pressing force of the sand mold is released, and the sand mold after suction casting can be taken out.

An electric control part: the power source AC220V is connected along the line via a fuse RThree loops are connected. 1. Connecting sand mold in-place contacts X simultaneously₁And an intermediate relay J₁Normally open self-protection contact J_1-1And a normally closed contact SJ connected to the time relay_1-1Meridian passage SJ_1-1Connecting intermediate relay J₁The coil is connected with the N end of the power supply; 2. normally open contact J for connecting intermediate relay_1-2Reconnection of time relay SJ₁Normally closed contact SJ_1-2，SJ_1-2Electromagnet DT connected with three branch circuits, electromagnetic change valve ₁② an electromagnet DT connected with the electromagnetic change valve₂Connecting pressure relay YJ₁，DJ₁、DJ₂And YJ₁Then the N end of the power supply is connected at the same time; 3. connecting pressure relay YJ₁Normally open contact YJ_1-1And then connected to the normally closed contact SJ of the time relay_1-3，SJ_1-3Electromagnet DT for simultaneously connecting electromagnetic directional valves₃And time relay SY₁，DT₃And SY₁Simultaneously, the N end of the power supply is connected;

the air control part: firstly, the air source is connected with DT through an air source purifier 8₁The electromagnetic directional valve 4, the air inlet end of the valve 4, connect the lower end air port of the suction casting upper chamber lifting cylinder 2 through the air inlet end, the air inlet of the upper end of the air cylinder 2 of the through-hole of the valve 4, the piston rod of the air cylinder 2 stretches out from the lower end and connects the top end of the suction casting upper chamber, control the upper chamber to go up and down, the air supply connects the pressure regulating valve 7, the valve 7 connects DT again₂The air inlet end of the electromagnetic directional valve 3 is connected with the lower end pipe orifice of the profiling cylinder 1, the air inlet opening of the valve 3 is connected with the upper end air inlet of the cylinder 1, and the lower end of the piston rod of the cylinder 1 is in floating connection with the profiling plate. Thirdly, the vacuum pump 9 is connected with DT through a vacuum purifier 16₃The air inlet of the vacuum pipeline valve 5 and the air outlet of the valve 5 communicated with the atmosphere are connected with the suction casting upper chamber 11.

The remarkable effect of the combination of the electric circuits is that the relay for pressing in place and the cylinder set for locking and sealing the suction casting chamber can be omitted, and the lowering and pressing of the chamber are completed at the same time, so that the time of the whole process is reduced.

Drawings

Figure 1a pneumatic control part

FIG. 1b electric control part

Wherein: 1. a profiling cylinder 2, a suction casting upper chamber lifting cylinder 3, an electromagnetic directional valve 4, an electromagnetic directional valve 5, a vacuum opening air valve 6, a pressure relay 7, a pressure regulating valve 8, an air source purifier 9, a vacuum pump 10, an air compressor 11, a suction casting upper chamber 12, a profiling plate 13, a valve electromagnet 14, an intermediate relay 15, a time relay 16, a vacuum purifier 17, a sand mold in-place signal

Detailed Description

When the suction casting upper chamber 11 is in signal descending process, the descending contour plate 12 can be in contact with the indoor sand mold before the suction casting upper chamber 11 is in contact with the indoor sand mold, when the suction casting upper chamber 11 continues descending, the contour plate 12 continuously compresses the sand mold, after the suction casting upper chamber 11 is in contact with the suction casting lower chamber flange, the pressure rises, the pressure relay 6 sends a signal after reaching a set value, the vacuum pipeline electromagnetic valve 5 is opened to connect the vacuum pipeline to cut off the atmosphere, and meanwhile, the sealing pressure is increased after the outside of the suction casting chamber 11 is subjected to normal atmospheric pressure. The vacuum pipe valve 5 draws the indoor air away to form negative pressure. The sand mold starts to be suction-cast, and the time relay 15 is used for timing, when the set value is reached, the normally closed contact of the time relay 15 is opened simultaneously to cut off the signal. The vacuum pipeline valve 5 is reversed, the vacuum is cut off to connect the atmosphere, simultaneously, the cylinders of the pressure plate 12 and the suction casting upper chamber 11 are reversed, the suction casting upper chamber 11 is opened and the pressure plate 12 is released, the pressure relay 6 is reset, and the suction casting chamber 11 is lifted.

Claims (1)

1. The simplified vacuum suction casting process program control electric loop is characterized in that:

an electric control part: the power supply (AC 220V) is connected to three loops along the line via fuses (R), 1. the sand-in-place contacts (X) are connected simultaneously₁) And an intermediate relay (J)₁) Normally open self-protection contact (J)_1-1) And a normally closed contact (SJ) of the time relay is connected at the same time_1-1) Scripture (SJ)_1-1) Connecting intermediate relay (J)₁) The coil is connected with the end of the power supply (N); 2. normally open contact of connecting intermediate relay (J)_1-2) Reconnecting the time relay (SJ)₁) Normally closed contact (SJ)_1-2），（SJ_1-2) Connect three at the same timeA branch circuit, i.e. an electromagnet (DT) connected with the electromagnetic directional valve₁) ② electromagnet (DT) connected with electromagnetic change valve₂) ③ connecting a pressure relay (YJ)₁），（DJ₁）、（DJ₂) And (YJ)₁) And then is connected with the power supply (N) end; 3. connecting pressure relay (YJ)₁) Normally open contact (YJ)_1-1) And then connecting the normally closed contact (SJ) of the time relay_1-3），（SJ_1-3) Electromagnet (DT) of electromagnetic directional valve connected simultaneously₃) And a time relay (SY)₁），（DT₃) And (SY)₁) Meanwhile, the power supply (N) end is connected;

the air control part: the upper chamber lifting air source is connected with DT through an air source purifier (8)₁Electromagnetic directional valve (4), DT₁The air inlet end of the electromagnetic directional valve (4) is connected with the air port at the lower end of the suction casting upper chamber lifting cylinder (2) through the air inlet end, DT₁The air inlet of the upper end of the suction casting upper chamber lifting cylinder (2) is connected with the air inlet of the atmosphere opening of the electromagnetic directional valve (4), the piston rod of the suction casting upper chamber lifting cylinder (2) extends out from the lower end to be connected with the top end of the suction casting upper chamber to control the upper chamber to lift, the pressure-type air source is connected with the pressure regulating valve (7), and the pressure regulating valve (7) is connected with the DT₂The air inlet end of the electromagnetic directional valve (3) is connected with the lower end pipe orifice of the profiling cylinder (1), DT₂The atmospheric vent of the electromagnetic directional valve (3) is connected with the upper end air inlet of the profiling cylinder (1), the lower end of the piston rod of the profiling cylinder (1) is connected with the profiling plate in a floating way, and the vacuum pump (9) in the vacuum air source is connected with DT through the vacuum purifier (16)₃The air inlet of the vacuum opening air valve (5) is connected with the suction casting upper chamber (11) through the air outlet of the vacuum opening air valve (5) communicated with the atmosphere.

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