Positive-pressure explosion-proof case with pressure detecting and explosion-proof controlled function
(1) technical field
The utility model relates to the analysis and Control field, relates in particular to the positive-pressure explosion-proof case with pressure detecting and explosion-proof controlled function.
(2) background technology
In fields such as metallurgy, building materials, petrochemical industry, chemical industry, a lot of equipment all will be operated in the inflammable and explosive place, and therefore the equipment that works in the hazardous area must will be accomplished explosion-proof design, and obtains explosion-proof authentication.Explosion-proof design has multiple mode, as positive-pressure explosion-proof, flame proof, intrinsic safe explosion-proof etc.Because positive-pressure explosion-proof has wide accommodation, superiority such as easy to operate, has obtained application more and more widely.
The mode that positive-pressure explosion-proof adopts usually is: in the positive-pressure explosion-proof case that electric equipment is housed in the protective gas feeding hazardous area; make the interior gas pressure of equipment greater than external atmospheric pressure; feed the original gas in enough protective gas displacement casees; make and be full of safe protective gas in each equipment; this moment, electric equipment can be switched on; after this protective gas that feeds certain flow makes in the equipment gas pressure keep certain malleation with respect to external atmosphere pressure, thereby it is explosion-proof that extraneous flammable explosive gas or dust are realized in can not access arrangement.In order to monitor the gas pressure in the positive-pressure explosion-proof equipment, usually mode is: use a flame proof differential pressure transmitter to monitor the air pressure of positive-pressure explosion-proof equipment internal pressure lowest part and the differential pressure of external atmosphere pressure, this differential pressure value is presented on the screen of transmitter, simultaneously differential pressure signal is converted to the 4-20mA current signal and be input in the positive-pressure explosion-proof control device.This positive-pressure explosion-proof control device goes to control the energising and the outage of the electric equipment of needs positive-pressure explosion-proof according to the above-mentioned differential pressure value that records.Concrete control timing and logic can be referring to the explosion-proof explosion-proof criterias of pressurized enclosure type.
Above-mentioned positive-pressure explosion-proof control device can be installed in the place of safety, also can be installed in the hazardous area.The advantage that is installed in the place of safety is not need the positive-pressure explosion-proof control device is carried out explosion-proof design, but shortcoming is that the distance between positive-pressure explosion-proof control device and the flame proof differential pressure transmitter may be far away, needs to lay long cable and corresponding crane span structure or coating steel pipe etc.The shortcoming that is installed in the hazardous area is to carry out explosion-proof design (adopting the flame proof design usually) to the positive-pressure explosion-proof control device, but has avoided the long-distance cable laying.
Prior art can realize positive-pressure explosion-proof preferably to the equipment in the inflammable explosive environments, but also come with some shortcomings, as: (1) inconvenience is installed, debugging and safeguarding: differential pressure transmitter, positive-pressure explosion-proof control device are placed apart, structure is disperseed, integrated level is low, and they are connected complex structure with cable, gas-tpe fitting, cable connector, the sealing device of positive-pressure explosion-proof case by numerous tracheaes, explosion-proof design; (2) cost height: differential pressure transmitter and positive-pressure explosion-proof control device, long-distance line cable and crane span structure, numerous gas-tpe fitting and the cable connector and sealing devices etc. of flame proof design have all improved cost.
(3) summary of the invention
In order to solve deficiencies such as production cost height, inconvenient installation and maintenance in the prior art, the utility model provides the positive-pressure explosion-proof case with pressure detecting and explosion-proof controlled function that a kind of production cost is low, be convenient to installation and maintenance.
The technical solution adopted in the utility model is:
A kind of positive-pressure explosion-proof case with pressure detecting and explosion-proof controlled function comprises casing, protective gas inflow device and bleeder, and protective gas inflow device and bleeder are installed on the casing; Described positive-pressure explosion-proof case comprises that also described pressure detecting and explosion-proof control device are installed near the tank wall place by the feed cable introducing device of pressure detecting and explosion-proof control module, flame proof design and ejector, the pressure-detecting device of flame proof design, pressure detecting and the explosion-proof control device that the flame proof housing is formed; The flame proof housing is made up of the matrix and the lid of flame proof design; Pressure detecting and explosion-proof control module are installed in the flame proof housing; Feed cable introducing device and ejector and pressure-detecting device are installed on the flame proof housing.
As preferably, the pressure-detecting device of described flame proof design is made up of the joint and the differential pressure pickup of flame proof design.
As preferably, described feed cable ejector is the hole by power line and embedding in the joint of flame proof design.
As preferably, display module is installed in the described flame proof housing, described display module is installed in the top of pressure detecting and explosion-proof control module, and the lid of the flame proof design that has transparent window is installed above display module.
As preferably, binding post is installed in the described flame proof housing, binding post connects pressure detecting and explosion-proof control module.
As preferably, the matrix of described flame proof design is and the casing die casting metallic object that cavity is arranged together.
As preferably, the lid of the case lid of described positive-pressure explosion-proof case and pressure detecting and explosion-proof control device is discrete.
Compared with prior art, the beneficial effects of the utility model are: (1) is easy to install, debugs and safeguards: pressure-detecting device and explosion-proof control device are installed in the same flame proof housing, and this pressure detecting and explosion-proof control device near or be adjacent to and be installed on the tank wall place, saved the tracheae that needs explosion-proof design between each device and joint, electric cable and joint, sealing device etc.; (2) cost is low: because the height of pressure transmitter, positive-pressure explosion-proof control device, positive-pressure explosion-proof case is integrated, saved numerous parts and material.
Description of drawings
Fig. 1 is a kind of internal structure schematic diagram of positive-pressure explosion-proof case;
Fig. 2 is a kind of schematic diagram of positive-pressure explosion-proof case;
Fig. 3 is the generalized section of a kind of flame-proof type pressure detecting and explosion-proof control device;
Fig. 4 is equipped with the generalized section that differential pressure pickup reaches the joint of the flame proof design of passing through power line;
Fig. 5 is the internal structure schematic diagram of another kind of positive-pressure explosion-proof case;
Fig. 6 is another kind of flame-proof type pressure detecting and explosion-proof control device schematic diagram;
Fig. 7 is the internal structure schematic diagram of the third positive-pressure explosion-proof case.
Embodiment
Below in conjunction with embodiment and accompanying drawing, the utility model is described in further detail.
Embodiment 1:
A kind of positive-pressure explosion-proof case with pressure detecting and explosion-proof controlled function shown in Fig. 1-4 comprises pressure detecting and explosion-proof control device, protective gas inflow device 51 and bleeder 52 that casing 1, flame proof design.Pressure detecting and explosion-proof control device are adjacent to and are installed on cabinet wall, need explosion-proof electric equipment 2 to be installed in the opposite side of casing 1, and protective gas flows into and bleeder is installed on the casing 1.
The matrix 33 that the pressure detecting of flame proof design and explosion-proof control device are designed by pressure detecting and explosion-proof control module 31, binding post 32, the joint 39 of flame proof design, the pressure-detecting device of flame proof design, display module 34, flame proof, the lid that has transparent window 37 of flame proof design are formed.The pressure-detecting device of flame proof is made up of joint 35, differential pressure pickup 36, the flame-retardant device 42 of flame proof design, and flame proof matrix 33 is and the casing 1 die casting metallic object that cavity is arranged together.Pressure detecting and explosion-proof control module 31, display module 34, binding post 32 are installed in the cavity of metallic matrix 33.The display module of being made up of display driver circuit and display screen 34 is installed in the top of pressure detecting and explosion-proof control module 31 and is electrically connected, and the lid 37 that has transparent window is installed on the flame proof matrix 33 by screw thread.
Joint 35 is installed on the matrix 33 and by O type circle 38 and matrix 33 and keeps sealing.The center of joint 35 has the hole, and differential pressure pick-up 36 is installed in the hole of joint 35, and and the inner hole wall of joint 35 between bonding with glue 44 sealings.The electrical lead wire of differential pressure pick-up 36 is connected to pressure detecting and explosion-proof control module 31.The one side of differential pressure pick-up 36 communicates with protective gas in the positive-pressure explosion-proof case by aperture 43, and another side communicates with matrix 33 cavities by sintering flame-retardant device 42.
The feed cable introducing device is that joint 39 is installed on the matrix 33, and matrix 33 internal cavities communicate with ambient atmosphere with the thread gaps of matrix 33 by joint 39; A pair of 24V power line passes wherein to be received on the binding post 32, and one the tunnel connects pressure detecting and explosion-proof control device then; Binding post 32 is received after by the relay in pressure detecting and the explosion-proof control module 31 in another road, is connected to electric equipment 2 by joint 35 leads 41 again.Power supply lead wire 41 passes the perforate 40 at joint 35 edges, carries out embedding after lead-in wire 41 passes this hole.
Have the hole on the cover plate 3 of casing 1, the lid 37 of pressure detecting and explosion-proof control device is exposed, be convenient to the maintenance of pressure detecting and explosion-proof control device; Cover plate 3 keeps sealing with casing 1, pressure detecting and explosion-proof control device respectively by two O type circles simultaneously.
Embodiment 2:
A kind of positive-pressure explosion-proof case with pressure detecting and explosion-proof controlled function shown in Fig. 1,2,3,4, as different from Example 1: described flame proof matrix 33 is metal derbies that there is cavity inside, is installed in the inside of casing 1, nestles up tank wall.The feed cable introducing device 39 of explosion-proof design is installed on the flame proof matrix 33 by screw thread, simultaneously the O type circle 50 of 1 of flame proof matrix 33 and casing is compressed, and makes that maintenance seals between flame proof matrix 33 and tank wall.
All the other structures are identical with embodiment 1 with the course of work.
Embodiment 3:
A kind of integrated pressure detecting shown in Fig. 5,6 and the positive-pressure explosion-proof case of explosion-proof control device, as different from Example 1: pressure detecting and explosion-proof control device are installed in outside the casing 1 and near tank wall, have two cavitys in the matrix 33, pressure detecting and explosion-proof control module 31, display module 34 are installed in the cavity, joint 35 connect boxes 1 and flame proof matrix 33; Binding post 32 is installed in another cavity; The feed cable ejector is joint 45 connect boxes 1 and flame proof matrix 33, and is inner by power line and embedding; Joint 35 and joint 45 all pass through O type circle and casing 1 sealing.
The cover plate of casing 1 keeps sealing by O type circle and casing 1.
All the other structures are identical with embodiment 1 with the course of work.
Embodiment 4:
A kind of positive-pressure explosion-proof case shown in Fig. 4,7 with pressure detecting and explosion-proof controlled function, as different from Example 1, the pressure detecting of flame proof design and explosion-proof control device are installed in outside the casing 1 and near tank wall, and the joint 35 of flame proof design keeps sealing by O type circle and tank wall.
All the other structures are identical with embodiment 1 with the course of work.