CN204052906U - Selfdecomposition ammonia sintering furnace - Google Patents

Abstract

Selfdecomposition ammonia sintering furnace, comprise agglomerating plant base, agglomerating plant base is provided with guipure importation, sintering main part, cooling down part and mesh-belt conveying part, and foraminous conveyer passes in the middle of sintering main part and cooling down part, and its one end is enclosed within guipure importation, the other end is enclosed within mesh-belt conveying part, heating partial is installed in sintering main part, and in sintering main part, the periphery of heating partial is provided with ammonia water back, liquefied ammonia is delivered to ammonia water back through ammonia heating input channel, the waste heat of sintering furnace self is utilized to realize selfdecomposition, effectively can reduce electrical heating and decompose the required electric energy consumed, the real-time detected value automatic switchover low and high level that PID control system is transmitted according to digital temperature sensor is with the conducting of control relay silicon controlled and disconnection, determine the electrified regulation time of heating partial, the impact produced electrical network is little, not only increase the economic benefit of system, and the service life of prolonged boiler.

Description

Selfdecomposition ammonia sintering furnace

Technical field

The utility model relates to sintering equipment technical field, particularly relates to a kind of selfdecomposition ammonia sintering furnace.

Background technology

In powdered metal parts is produced, sintering is the critical process determining final products microstructure mechanical property and controlling dimension, at high temperature, make the mutual binding of green compact solid particle, crystal is grown up gradually, hole and crystal boundary gradually reduce, and finally become and have certain microstructural dense multicrystalline sintered body.In modern sintering process equipment, many employings nitrogen-based atmosphere gas is as sintering protective gas, and mostly nitrogen-based atmosphere gas is to be transformed by ammonolysis craft, current ammonolysis craft mainly adopts independent resolving device, be delivered to agglomerating plant after decomposing purifying to use, manufacturer in conversion ammonolysis craft process more adopts electrical heating to decompose, and the decomposition of ammonia is heat absorption power consumption process, not only consume energy high, and pressed compact is at warm-up phase, because the gaseous product after pressed compact in-lubricant (zinc stearate) decomposes is overflowed rapidly from powder compact, burn discharged to fire door with furnace atmosphere, if too fast at this stage programming rate, because decomposition gas is overflowed too quickly from pressed compact, easily cause pressed compact surface blistering and distortion, there is puffed rice phenomenon, pressed compact is not incubated the sufficiently long time at the specified temperature simultaneously, and then causes the physical and mechanical properties needed for sintered part(s) obtained to decline.In addition, the preheating zone of furnace core tube, preheating speed is slow, and relative preheating time is long, adds the body of heater length of preheating zone, and occupation area of equipment is large, adds the Productive statistics in early stage of manufacturer to a certain extent.

High temperature sintering furnace controls as a typical case of process control, and its dynamic characteristic has Great inertia, the large feature postponed, and with complicated factors such as non-linear, close couplings; And sintering furnace automatic control system is the core system of process control, production control, data management, its control effects directly affects production cost and product quality.The control of current domestic high temperature sintering furnace mainly adopts bang-bang control, or even Artificial Control, adopts the stability of a system of this two classes control method bad, and overshoot is large, and environmental change response is slow to external world simultaneously, poor real.In addition, switching over produces very large impact to electrical network frequently, not only reduces the economic benefit of system, and decreases the service life of boiler.Therefore the economy of control method to raising sintering system, the stability of studying a kind of the best are significant.

Utility model content

The technical problem that the utility model solves is to provide a kind of selfdecomposition ammonia sintering furnace, to solve the shortcoming in above-mentioned background technology.

The technical problem that the utility model solves realizes by the following technical solutions:

Selfdecomposition ammonia sintering furnace, comprise agglomerating plant base, agglomerating plant base is disposed with from left to right guipure importation, sintering main part, cooling down part and mesh-belt conveying part, and foraminous conveyer passes in the middle of sintering main part and cooling down part, and its one end is enclosed within guipure importation, the other end is enclosed within mesh-belt conveying part, does circulation feed motion under the drive of mesh-belt conveying part, heating partial is installed in sintering main part, and in sintering main part, the periphery of heating partial is provided with ammonia water back, ammonia heating input channel one end is connected with ammonolysis craft control section, the other end heats feedback pipeline by ammonia water back with ammonia and is connected, and ammonia heating feedback pipeline is connected with ammonolysis craft control section through ammonia water back, one end, hydrogen delivery tube road is connected with ammonolysis craft control section, the other end and nitrogen base protect gas mixing arrangement to be connected, nitrogen gas delivery-line one end is connected with ammonolysis craft control section, the other end and nitrogen base protect gas mixing arrangement to be connected, and control valve is provided with in nitrogen gas delivery-line, control valve is connected with cooling protection gas dispersal device by cooling protection letter shoot road, nitrogen base protection gas mixing arrangement is provided with dewaxing protective gas conveyance conduit and quenching nitrogen-based gas conveyance conduit, and the protective gas conveyance conduit that dewaxes is connected with dewaxing part, quenching nitrogen-based gas conveyance conduit is connected with gas quenching part, in addition, cooling protection gas dispersal device is connected with cooling down part, plays a protective role, and cooling recirculation system is connected with quench cooled part, cooling down part respectively, and quench cooled part is used for quench cooled, and cooling down part is used for rear end cooling.

In the utility model, in cooling recirculation system, input has cooling water, and cooling water is circulation external cooling type.

In the utility model, quench cooled part and cooling down beneath portions are respectively arranged with cooling water recovery channel, and cooling water recovery channel is connected with cooling bay, and cooled water is transmitted back to cooling bay through cooling water recovery channel, for again recycling.

In the utility model, heating partial for segmented is installed in parallel, is convenient to detachable maintaining in sintering main part.

In the utility model, in heating partial, be provided with thermocouple, and thermocouple is connected with digital temperature sensor, and digital temperature sensor is connected with ammonolysis craft control section.

In the utility model, ammonolysis craft control section comprises cabinet, controller is provided with in cabinet, cabinet is provided with guidance panel, and guidance panel is connected with controller, and cabinet is circumscribed with photoelectrical coupler, photoelectrical coupler is connected with relay, and relay is connected with heating partial, controller by the silicon controlled conducting of low and high level control relay and disconnection, thus controls the electrified regulation time of heating partial.

In the utility model, ammonia heating input channel is provided with ammonia flow control valve, by controlling the input speed of ammonia, to control ammonia in the temperature exported after heating.

In the utility model, ammonia water back is helical structure, utilize sintering waste heat by input to ammonia water back liquefied ammonia thermal conversion for gaseous ammonia time, ammonia water back pre-heating temperature elevation speed is even, decomposition rate is stablized, and when the gas after decomposition is used for front end preheating dewaxing, can prevent because dewaxing decomposition gas is overflowed too quickly from pressed compact, cause pressed compact surface blistering and distortion, occur puffed rice phenomenon; And helical structure decreases occupation area of equipment, effectively reduce the Productive statistics in early stage of manufacturer.

Selfdecomposition ammonia sintering furnace control method, controller adopts PID control system, according to the control deviation that system set-point and digital temperature sensor real output value are formed, the ratio of deviation, integration and differential are formed controlled quentity controlled variable by linear combination, controlled device is controlled, namely heating partial is controlled, pass through self-adaptative adjustment, optimize nonlinear temperature deviation, realize temperature Automated condtrol, its concrete steps are as follows:

1) take liquefied ammonia as raw material, and liquefied ammonia is delivered to ammonolysis craft control section, liquefied ammonia inputs in the ammonia water back arranged with the periphery of heating partial in sintering main part through ammonia heating input channel;

2) utilize sintering waste heat to be gaseous ammonia by the liquefied ammonia thermal conversion inputing to ammonia water back, digital temperature sensor detects ammonia water back peripheral temperature in real time, and digital temperature sensor real output value is transferred to controller;

3) by step 2) in gaseous ammonia through ammonia heating feedback pipeline send ammonolysis craft control section back to, decompose under the effect of catalyst, obtain hydrogen and nitrogen, also has the impurity such as residual ammonia, water vapour of trace simultaneously, then purified gas and impurity after decomposition by clarifier, purified gas isolates hydrogen and nitrogen by cyclone separator;

4) by step 3) in isolated hydrogen and nitrogen be delivered to nitrogen base and protect gas mixing arrangement to be mixed to get mist, its a part of mist is delivered in dewaxing part through dewaxing protective gas conveyance conduit and carries out dewaxing preheating, and another part mist is delivered to gas quenching part through quenching nitrogen-based gas conveyance conduit and carries out nitrogen-based atmosphere protection quenching;

5) nitrogen gas delivery-line is provided with control valve, part nitrogen is through control valve difference output and flow to cooling protection gas dispersal device by cooling protection letter shoot road, after cooling protection gas dispersal device is dispersed, be full of cooling down part, shield;

6) through above-mentioned steps 1) ~ step 5) liquefied ammonia selfdecomposition after, cooling water is inputted by cooling recirculation system, part cooling water exports through quench cooled part and is used for quench cooled, and part cooling water is delivered to cooling down part and cools for rear end.

In the utility model, the real output value of the system set-point inputted by guidance panel and digital temperature sensor is converted into digital quantity computing by PID control system, and formula is as follows:

$u\left(k\right)=K_{p}e\left(t\right)+K_i\underset{j=0}{\overset{k}{\mathrm{\Σ}}}e\left(j\right)+K_d[e\left(k\right)-e(k-1)]---(1-1)$

K--digital temperature sensor sampling sequence number in formula (1-1), k=0,1,2

U (k)--kth time gathers moment controller output valve;

E (k)--kth time gathers the deviate of moment guidance panel input system set-point;

E (k-1)--the deviate of (k-1) secondary collection moment guidance panel input system set-point;

K _p--proportionality coefficient;

K _i--integral coefficient, K _i=K _pt/T _i;

K _d--differential coefficient, K _d=K _pt _d/ T;

The T--sampling period, T _i--the time of integration coefficient, T _d--derivative time coefficient;

By (1-1) Shi Ke get,

Δu(k)＝u(k)-u(k-1)＝K _p[e(k)-e(k-1)]+K _ie(k)-K _D[e(k)-2e(k-1)+e(k-2]＝K _pΔe(k)+K _ie(k)+K _D[Δe(k)-Δe(k-1)]

(1-2)

Δ e (k)=e (k)-e (k-1) in formula (1-2), Δ e (k) is incremental timestamp algorithm, gathered and calculate controlled quentity controlled variable output increment, and sampling period T is constant, will determine K by kth time _i, K _d, K _pcoefficient, use measured value deviation 3 times, can calculate the increment of controlled quentity controlled variable, therefore during equipment fault, impact is less, simultaneously by the silicon controlled conducting of low and high level control relay and the disconnection of controller, little to the impact of electrical network generation when automatically switching, realize a smooth transition, not only increase the economic benefit of system, and the service life of prolonged boiler, and ensureing controlled device stable while, eliminate error as far as possible; Increase K _pproportionality coefficient, can accelerate the response ratio of system, but work as K _pwhen proportionality coefficient is excessive, system will produce overshoot, destroy the stability of a system; Increase the T time of integration _ibe conducive to reducing overshoot, the stability of maintenance system; Increase T _dbe conducive to accelerating system responses, overshoot is reduced, increase the stability of a system; Operating personnel by gathering the response curve of examination method observing system, more repeatedly to debug the impact of system responses according to each regulating parameter and determine regulating parameter, to reach Optimal Control effect; PID control system with the conducting of control relay silicon controlled and disconnection, thus determines the electrified regulation time of heating partial according to the real output value automatic switchover low and high level of digital temperature sensor.

For improving the self-regulation of controller, in controller, being provided with proportional controller, and forming closed loop, by changing proportionality coefficient, the regulating parameter of correcting controller, in this, as benchmark, optimizing nonlinear temperature deviation, realizing temperature Automated condtrol.

Beneficial effect: the utility model utilizes the waste heat of sintering furnace self to ammonia heating to realize ammonia selfdecomposition, effectively the required electric energy consumed is decomposed in reduction electrical heating; And ammonia water back is helical structure, pre-heating temperature elevation speed is even, can prevent puffed rice phenomenon; And helical structure decreases occupation area of equipment, reduce the Productive statistics in early stage of manufacturer; PID control system is adopted with Time Controller, little to the impact of electrical network generation when automatically switching, realize a smooth transition, not only increase the economic benefit of system, and the service life of prolonged boiler.

Accompanying drawing explanation

Fig. 1 is the structural representation of preferred embodiment of the present utility model.

Detailed description of the invention

The technological means realized to make the utility model, creation characteristic, reaching object and effect is easy to understand, below in conjunction with concrete diagram, setting forth the utility model further.

See the selfdecomposition ammonia sintering furnace of Fig. 1, comprise cooling recirculation system 1, quench cooled part 2, gas quenching part 3, foraminous conveyer 4, heating partial 5, dewaxing part 6, dewaxing protective gas conveyance conduit 7, ammonia heating feedback pipeline 8, ammonia heating input channel 9, ammonolysis craft control section 10, hydrogen delivery tube road 11, nitrogen gas delivery-line 12, control valve 13, quenching nitrogen-based gas conveyance conduit 14, cooling water recovery channel 15, nitrogen base protection gas mixing arrangement 16, cooling protection letter shoot road 17, cooling down part 18, mesh-belt conveying part 19, cooling protection gas dispersal device 20, sintering main part 21, agglomerating plant base 22 and guipure importation 23.

In the present embodiment, agglomerating plant base 22 is disposed with guipure importation 23 from left to right, sintering main part 21, cooling down part 18 and mesh-belt conveying part 19, foraminous conveyer 4 passes from sintering main part 21 and cooling down part 18 are middle, and two ends are enclosed within guipure importation 23 and mesh-belt conveying part 19, circulation feed motion is done under the drive of mesh-belt conveying part 19, under external control, as required material is delivered to right-hand member from left end, complete successively in the process: dewaxing preheating, electrical heating sinters, nitrogen-based gas protection quenching and nitrogen-based gas protection cooling down operation,

Heating partial 5 is installed in sintering main part 21, and be installed in parallel for segmented, be convenient to detachable maintaining, and in sintering main part 21, the periphery of heating partial 5 is provided with ammonia water back, the decomposition temperature of ammonia is at 800 ~ 850 DEG C, the sintering range of iron is at 1200 ~ 1350 DEG C, ammonia inputs through ammonia heating input channel 9, utilize sintering waste heat by the heating of the ammonia of input, and the input speed of ammonia is controlled by ammonia flow control valve, to control ammonia in the temperature exported after heating, ammonia after heating is delivered to ammonolysis craft control section 10 through ammonia heating feedback pipeline 8, decompose under the effect of catalyst, decompose through ammonolysis craft control section 10, isolation, export after purifying, hydrogen exports through hydrogen delivery tube road 11, nitrogen exports through nitrogen gas delivery-line 12, and hydrogen and nitrogen are after nitrogen base protects gas mixing arrangement 16 to mix, a part is delivered in the dewaxing part 6 of front end through dewaxing protective gas conveyance conduit 7 carries out dewaxing preheating, another part is delivered to gas quenching part 3 through quenching nitrogen-based gas conveyance conduit 14 and carries out nitrogen-based atmosphere protection quenching, wherein, nitrogen partial in nitrogen gas delivery-line 12 is through control valve 13 difference output and flow to cooling protection gas dispersal device 20 by cooling protection letter shoot road 17, the inside of the whole cooling down part 18 in rear end is full of after cooling protection gas dispersal device 20 is dispersed, play a protective role, the cooling water that cooling recirculation system 1 inputs, part exports through quench cooled part 2 and is used for quench cooled, and part is delivered to cooling down part 18 and cools for rear end.

In the present embodiment, cooling water is circulation external cooling type, and cooled water is transmitted back to cooling bay through cooling water recovery channel 15, for again recycling.

In the present embodiment, ammonolysis craft control section 10 comprises cabinet, controller is provided with in cabinet, cabinet is provided with guidance panel, guidance panel is connected with controller, and cabinet is circumscribed with photoelectrical coupler, photoelectrical coupler is connected with relay, and relay is connected with heating partial 5, when there is deviation in the real output value of digital temperature sensor, PID control system according to the real output value automatic switchover low and high level of digital temperature sensor with the conducting of control relay silicon controlled and disconnection, thus determine the electrified regulation time of heating partial 5, the impact produced electrical network is little, can realize a smooth transition, not only increase the economic benefit of system, and the service life of prolonged boiler, and ensureing controlled device stable while, eliminate error as far as possible.

In the present embodiment, liquefied ammonia inputs through ammonia heating input channel 9, utilizes sintering waste heat by the heating of the liquefied ammonia of input, exports after realizing selfdecomposition, isolation, purifying in ammonolysis craft control section 10, effectively can reduce electrical heating and decompose the required electric energy consumed; Ammonia water back is helical structure simultaneously, utilize sintering waste heat by input to ammonia water back liquefied ammonia thermal conversion for gaseous ammonia time, ammonia water back pre-heating temperature elevation speed is even, can prevent because decomposition gas is overflowed too quickly from pressed compact, cause pressed compact surface blistering and distortion, occur puffed rice phenomenon; And helical structure decreases occupation area of equipment, effectively reduce the Productive statistics in early stage of manufacturer.

More than show and describe general principle of the present utility model and principal character and advantage of the present utility model.The technical staff of the industry should understand; the utility model is not restricted to the described embodiments; what describe in above-described embodiment and description just illustrates principle of the present utility model; under the prerequisite not departing from the utility model spirit and scope; the utility model also has various changes and modifications, and these changes and improvements all fall within the scope of claimed the utility model.The claimed scope of the utility model is defined by appending claims and equivalent thereof.

Claims (8)

1. selfdecomposition ammonia sintering furnace, comprise agglomerating plant base, it is characterized in that, agglomerating plant base is disposed with from left to right guipure importation, sintering main part, cooling down part and mesh-belt conveying part, and foraminous conveyer passes in the middle of sintering main part and cooling down part, and its one end is enclosed within guipure importation, the other end is enclosed within mesh-belt conveying part, heating partial is installed in sintering main part, and in sintering main part, the periphery of heating partial is provided with ammonia water back, ammonia heating input channel one end is connected with ammonolysis craft control section, the other end heats feedback pipeline by ammonia water back with ammonia and is connected, and ammonia heating feedback pipeline is connected with ammonolysis craft control section through ammonia water back, one end, hydrogen delivery tube road is connected with ammonolysis craft control section, the other end and nitrogen base protect gas mixing arrangement to be connected, nitrogen gas delivery-line one end is connected with ammonolysis craft control section, the other end and nitrogen base protect gas mixing arrangement to be connected, and control valve is provided with in nitrogen gas delivery-line, control valve is connected with cooling protection gas dispersal device by cooling protection letter shoot road, nitrogen base protection gas mixing arrangement is provided with dewaxing protective gas conveyance conduit and quenching nitrogen-based gas conveyance conduit, and the protective gas conveyance conduit that dewaxes is connected with dewaxing part, quenching nitrogen-based gas conveyance conduit is connected with gas quenching part, in addition, cooling protection gas dispersal device is connected with cooling down part, and cooling recirculation system is connected with quench cooled part, cooling down part respectively.

2. selfdecomposition ammonia sintering furnace according to claim 1, is characterized in that, in cooling recirculation system, input has cooling water, and cooling water is circulation external cooling type.

3. selfdecomposition ammonia sintering furnace according to claim 1, is characterized in that, quench cooled part and cooling down beneath portions are respectively arranged with cooling water recovery channel, and cooling water recovery channel is connected with cooling bay.

4. selfdecomposition ammonia sintering furnace according to claim 1, is characterized in that, heating partial is installed in parallel for segmented in sintering main part.

5. selfdecomposition ammonia sintering furnace according to claim 1, it is characterized in that, be provided with thermocouple in heating partial, and thermocouple is connected with digital temperature sensor, and digital temperature sensor is connected with ammonolysis craft control section.

6. selfdecomposition ammonia sintering furnace according to claim 1, it is characterized in that, ammonolysis craft control section comprises cabinet, controller is provided with in cabinet, cabinet is provided with guidance panel, and guidance panel is connected with controller, and cabinet is circumscribed with photoelectrical coupler, photoelectrical coupler is connected with relay, and relay is connected with heating partial.

7. selfdecomposition ammonia sintering furnace according to claim 1, is characterized in that, ammonia heating input channel is provided with ammonia flow control valve.

8. selfdecomposition ammonia sintering furnace according to claim 1, is characterized in that, ammonia water back is helical structure.