CN208249346U - A kind of Squeezinggranulator shutoff control unit - Google Patents

Abstract

The utility model provides a kind of Squeezinggranulator shutoff control unit: including blow valve port, instrument wind distributor, instrument wind pipeline, instrument wind isolating valve, instrument wind blowback line isolating valve, tuning fork level switch, tuning fork casing and tuning fork baffle；The tuning fork casing is welded in pellet buffering tank, and tuning fork level switch is mounted on tuning fork casing and protrudes into tank interior；Tuning fork baffle is welded in pellet buffering top tank structure, is located at right above tuning fork level switch；The blow valve port is located at immediately below tuning fork level switch, connect with instrument wind pipeline one end, and instrument wind blowback line isolating valve is housed, and the instrument wind pipeline other end is connected to instrument wind distributor and equipped with instrument wind isolating valve.The utility model solves the problems, such as that Tuning Fork Switch false alarm causes the unplanned parking of Squeezinggranulator, improves the stability and reliability of system operation.

Description

A kind of Squeezinggranulator shutoff control unit

Technical field

The utility model relates to linear low density polyethylene Squeezinggranulator shutoff control units, in particular to avoid squeezing Pelletizer leads to the device of parking because of false alarm.

Background technique

In polyolefin granulating system, polyolefin resin and different type additive that reactor polymerization reaction obtains are mixed It closes, the mixing by extrusion granulation unit reaches molten condition, under the action of twin-screw extruder pelletizer and melting gear pump, It is delivered to drier dehydration after carrying out granulation underwater by template, dewatered dry polyolefin particles are sieved by vibrating screen, Qualified polyolefin particles enter pellet surge tank, send through blast system to finished product bin.

If blast system failure, polyethylene particle normally can not pass through pellet surge tank according to zero material position, and in pellet It is constantly accumulated in surge tank, causes granulating system that major accident occurs, for this purpose, dress is opened there are two tuning fork material position on pellet surge tank It closes, one is material position height report switch, plays warning note；The other is the high report switch of material position, is patrolled with extrusion granulation unit Interlocking is collected, the high report of material position, which switchs the alarm signal generated, will trigger the emergency stopping system (ESD) of extrusion granulation unit.By Mutual rubbing action in pellet transmission process between particle can generate a certain amount of powder and be adhered on tuning fork probe, Tuning fork level switch false alarm is caused, extrusion granulation unit is caused frequently to stop.

Chinese patent CN102914345A discloses a kind of level switch and bin-level monitoring method, wherein in material position After switch generates alarm signal, the probe of level switch is purged, level switch is detected within certain interval time is It is no to generate new alarm signal, if it is not, then judging previous alarm signal for false alarm, if so, judging previous alarm signal Number be non-false alarm.But the patent uses only a level switch, and blow device is long-pending to level switch along feedstock direction Ash is purged, and can not effectively solve the problems, such as the level switch false alarm that dust causes in continuous conveying process, and deterministic process Alarm procedure is lagged behind, reliability is lower.

Summary of the invention

The purpose of this utility model is to provide a kind of Squeezinggranulator shutoff control units, and extrusion granulation system can be improved The operation stability of system, reliability.

In order to achieve the above objectives, the utility model uses following technical scheme:

The control device includes pellet surge tank, is set on pellet surge tank and is with stopping in emergency for Squeezinggranulator Blowback component system connected multiple tuning fork level switch and purged for the probe to tuning fork level switch, the grain The upper end of material surge tank is provided with the feed inlet being connected with Squeezinggranulator, and the lower end of pellet surge tank is provided with discharge port, respectively The probe of tuning fork level switch is evenly arranged in pellet surge tank, and the blowback component includes being set to each tuning fork level switch The blow valve port of lower section and the probe baffle being set to above each tuning fork level switch.

Preferably, in the circumferential direction of the pellet surge tank uniform intervals be provided with it is multiple be connected inside pellet surge tank Logical casing is provided with a tuning fork level switch in each casing.The outer end of the certainly corresponding casing of the probe of tuning fork level switch The lower section of probe baffle is stretched to direction obliquely.

Preferably, the tuning fork level switch is three, and three tuning fork level switch are according to any two of them tuning fork material Bit switch is connected with the chain triggering mode of the emergency stopping system of the Squeezinggranulator with the emergency stopping system.

Preferably, the angle of the tuning fork level switch and horizontal plane is 20-30 degree.

Preferably, the probe baffle plate setting is in the inner wall of the pellet surge tank, and is covered in corresponding (respectively lower section) Respectively there is interval between probe baffle, it is ensured that pellet can pass through pellet buffering in the top of the probe of tuning fork level switch Tank.

Preferably, it is described probe baffle be selected from by the board material splice with some strength and electric conductivity at section be herringbone The structure of type.

Preferably, the blow valve port is protruded into and is fixed in pellet surge tank, and the purge stream that blow valve port issues is with oblique On direction be directed toward the probe of corresponding (respectively top) tuning fork level switch.

Preferably, the purge stream exit direction of the blow valve port and the angle of horizontal plane are 60-70 degree.

Preferably, the control device further includes instrument wind distributor, instrument wind pipeline, instrument wind isolating valve and instrument wind Blowback line isolating valve, one end of instrument wind pipeline passes through instrument wind blowback line isolating valve respectively and is connected with corresponding blow valve port, another End is connected by instrument wind isolating valve with instrument wind distributor.

Preferably, the control device further includes the DCS control interface for showing each tuning fork level switch state.

The beneficial effects of the utility model are embodied in:

The utility model carries out reverse blow to tuning fork level switch using underlying blow valve port, and in tuning fork material position Baffle is arranged in switch top, effectively reduces the probability of level switch false alarm, solves continuous conveying in the process due to tuning fork The problem of level switch adhering powder causes false alarm and triggers extrusion granulation unit ESD, effectively reduces extrusion granulation unit The unplanned parking frequency improves the stability and reliability of granulating system operation.

Further, the utility model is by the tuning fork level switch quantity that connect the ESD with Squeezinggranulator by one A increase is three, is conducive to the real-time and reliability that improve alarm.

Further, the utility model passes through angle to tuning fork level switch and horizontal plane, blow valve port and horizontal plane The restriction of angle, the purging band for guaranteeing that the instrument wind of blow valve port generates can not only be purged on probe, and powder can be improved End purging efficiency.

Detailed description of the invention

Fig. 1 is the installation of tuning fork level switch and backflow structure schematic diagram；

In figure: 1 being pellet surge tank, 2 be tuning fork level switch, 3 be casing, 4 be baffle, 5 be blow valve port, 6 be instrument Wind blowback line isolating valve, 7 be instrument wind isolating valve, 8 be instrument wind pipeline, 9 be instrument wind distributor.

Specific embodiment

Below in conjunction with drawings and examples, the present invention will be further described in detail.

The present embodiment is by taking the application in polyethylene extrusion granulation system as an example.Squeezinggranulator shutoff control unit is set Meter thinking is to increase the high report switch of two material positions, and by its logical interlock with extrusion granulation unit by an intrinsic " choosing One " type is changed to " three select two " type, reduces the probability of tuning fork level switch wrong report, improves real-time, while each tuning fork material position The tuning fork of switch designs blow valve port, carries out reverse blow (opposite with feedstock direction) to tuning fork using instrument wind, it is ensured that powder is not Can be adhered on tuning fork causes to alarm and trigger extrusion granulation unit ESD, effectively avoids causing because of tuning fork level switch false alarm The parking of extrusion granulation unit.

As shown in Figure 1, the Squeezinggranulator shutoff control unit includes the high report Tuning Fork Switch of three material positions, material position height Height report switch " three select two " triggering extrusion granulation unit ESD and the blow valve port 5 for tuning fork blowback.Wherein, by two tuning fork material Bit switch 2 is mounted on the high report switch sustained height horizontal plane in 1 raw material position of pellet surge tank, thus high in an original material position Average arrangement installs the high report switch of two material positions again on the basis of report switch；Specific mounting means are as follows: on pellet surge tank 1 Tuning fork casing 3 is tilted down and is welded in tapping on 1 tank body of pellet surge tank by aperture, with 1 tank body horizontal line of pellet surge tank In 20-30 degree angle, 3 length of tuning fork casing is 165mm, and one end of tuning fork casing 3 is concordant with inner tank wall, tuning fork level switch 2 tuning fork (probe) is protruded into pellet surge tank 1 by the other end of tuning fork casing 3.The extrusion granulation unit ESD be installed on The alarm signal of tuning fork level switch 2 on tuning fork casing 3 forms logical relation.The upward oblique weld of the blow valve port 5 is in grain Expect in 1 tank body of surge tank, be located at 3 underface 150mm of tuning fork casing, blow valve port 5 and 1 tank body horizontal line of pellet surge tank are in 60- 70 degree of angles, be mainly used for avoiding particle, powder accumulation on tuning fork and caused by false alarm.Right above the tuning fork casing 3 200mm is welded with the tuning fork baffle 4 positioned at 1 inner tank wall of pellet surge tank, and tuning fork baffle 4 is for avoiding pellet dropping process pair Tuning fork generates impact, causes tuning fork level switch false alarm.

The size of the pellet surge tank 1 is outer diameter 2300mm, and height 2950mm, the tuning fork baffle 4 is by two pieces of 150mm The stainless steel plate of × 250mm is welded into " people " font, then is welded on 1 inner tank wall of pellet surge tank.

The logical interlock that the extrusion granulation unit ESD is used are as follows: (the high report of material position of two of them tuning fork level switch 2 Switch) same to alarm, extrusion granulation unit ESD can be just triggered, and three tuning fork level switch of real-time display on DCS picture 2 (i.e. high report switch LAHH713009-1, LAHH713009-2, LAHH713009-3 of material position in Fig. 1) states, in order to timely It was found that alarming and being handled.

The blow valve port 5 is connected with instrument wind pipeline 8, and one end that instrument wind pipeline 8 is connected with each blow valve port 5 is set respectively Having instrument wind blowback line isolating valve 6, (convenient for individually control, wherein some blow valve port, the dust of removing adherency immediately release report Alert state), 8 other end of instrument wind pipeline connect with instrument wind distributor 9 and is equipped with instrument wind isolating valve 7 (convenient for start and stop instrument Air hose line, such as when material position height report switch does not carry out warning note, can suitably be reduced or switched off instrument wind supply).It uses Instrument wind purges the tuning fork of three tuning fork level switch 2, it is ensured that the powder in pellet surge tank 1 will not be adhered to tuning fork On.

The instrument wind pipeline 8 is 12 stainless steel tube of Ф, is connected by 12 thread type loose joint head of Ф.

Working principle: when blast system operates normally, the polyethylene particle of extrusion forming through the charging of pellet surge tank 1, Finished product bin is delivered to after discharging, due to the wind pressure disturbance that blow valve port 5 provides, into the polyethylene particle institute of pellet surge tank 1 The powder of carrying can not be contacted, is adhered on the tuning fork of tuning fork level switch 2.When blast system breaks down, polyethylene Grain is gradually accumulated in pellet surge tank 1, until wind pressure perturbation action stops after covering blow valve port 5, polyethylene particle or powder The tuning fork of tuning fork level switch 2 is contacted, alarm signal is caused, when two of them tuning fork level switch 2 generates alarm signal, then ESD is triggered, so that extrusion granulation unit stops.

The advantages of the utility model, is as follows:

(1) the utility model structure is simple, cost of investment is minimum, without human intervention.

(2) the utility model is conducive to the real-time and reliability that improve alarm by increasing tuning fork level switch.

(3) in DCS real-time display tuning fork level switch state, processing alarm can be checked effectively, in time.

(4) tuning-fork type material position is high during the utility model solves continuous conveying using back-flushing technique combination baffle design The problem of height report switch false alarm, reduces the probability of false triggering ESD, effectively reduces the Squeezinggranulator parking frequency, reliably Property it is high.

(5) the utility model using instrument wind as purge gass, safety non-pollution, without additional energy, at low cost.Using every Setting from valve is conducive to improve control and maintenance efficiency.

(6) the utility model effectively reduces equipment parking rate, improves system run all right, reduces equipment accident Loss, while unit consumption of product is reduced, effectively raise economic benefit.

Claims (10)

1. a kind of Squeezinggranulator shutoff control unit, it is characterised in that: the control device includes pellet surge tank (1), setting In the multiple tuning fork level switch (2) being connected with the emergency stopping system of Squeezinggranulator on pellet surge tank (1) and use It is provided with and squeezes in the upper end of the blowback component that the probe to tuning fork level switch (2) is purged, the pellet surge tank (1) The feed inlet for pressing pelletizer connected, lower end are provided with discharge port, and it is slow that the probe of each tuning fork level switch (2) is evenly arranged in pellet It rushes in tank (1), the blowback component includes being set to the blow valve port (5) below each tuning fork level switch (2) and being set to each Probe baffle (4) above tuning fork level switch (2).

2. a kind of Squeezinggranulator shutoff control unit according to claim 1, it is characterised in that: the pellet surge tank (1) uniform intervals are provided with multiple casings (3) being connected with the pellet surge tank (1) inside, each casing (3) in circumferential direction Inside it is provided with a tuning fork level switch (2).

3. a kind of Squeezinggranulator shutoff control unit according to claim 1 or claim 2, it is characterised in that: the tuning fork material position Switching (2) is three, and three tuning fork level switch (2) are made according to any two of them tuning fork level switch (2) and the extruding The triggering mode that the emergency stopping system of grain machine is chain is connected with the emergency stopping system.

4. a kind of Squeezinggranulator shutoff control unit according to claim 1 or claim 2, it is characterised in that: the tuning fork material position The angle for switching (2) and horizontal plane is 20-30 degree.

5. a kind of Squeezinggranulator shutoff control unit according to claim 1, it is characterised in that: the probe baffle (4) It is set to the inner wall of the pellet surge tank (1), and is covered in the top of the probe of corresponding tuning fork level switch (2), it is each to pop one's head in There is interval between baffle (4).

6. a kind of Squeezinggranulator shutoff control unit according to claim 1, it is characterised in that: the probe baffle (4) Selected from by the board material splice with some strength and electric conductivity at section be chevron shaped structure.

7. a kind of Squeezinggranulator shutoff control unit according to claim 1, it is characterised in that: the blow valve port (5) is stretched Enter and be fixed in pellet surge tank (1), the purge stream that blow valve port (5) issues is directed toward corresponding tuning fork material with direction obliquely The probe of bit switch (2).

8. according to claim 1 or a kind of 7 Squeezinggranulator shutoff control units, it is characterised in that: the blow valve port (5) Purge stream exit direction and the angle of horizontal plane be 60-70 degree.

9. a kind of Squeezinggranulator shutoff control unit according to claim 1, it is characterised in that: the control device also wraps Include instrument wind distributor (9), instrument wind pipeline (8), instrument wind isolating valve (7) and instrument wind blowback line isolating valve (6), instrument wind One end of pipeline (8) passes through instrument wind blowback line isolating valve (6) respectively and is connected with corresponding blow valve port (5), and the other end passes through instrument Wind isolating valve (7) is connected with instrument wind distributor (9).

10. a kind of Squeezinggranulator shutoff control unit according to claim 1, it is characterised in that: the control device is also Including for showing the control interface of each tuning fork level switch (2) state.