阅读说明：本技术 船用汽轮机用汽封压力调整装置 (Steam seal pressure adjusting device for marine steam turbine ) 是由 王晗 许涛 高怡秋 姚垒 李典来 于 2020-05-18 设计创作，主要内容包括：本发明涉及一种船用汽轮机用汽封压力调整装置,包括壳体、滑阀、活塞、滑杆、套筒、油动机,油动机与壳体固定连接,油动机的活塞通过滑杆与滑阀连接成一个体,壳体上部连接有套筒,套筒内配合连接有滑阀,套筒下部侧面开有窗口,窗口连通套筒侧面的排气口；套筒上端设有连接汽封平衡系统的接口,套筒下端设有进气口,滑杆中部设有向内收缩的变径轴,且变径轴置于套筒下端的进气口内；壳体上部两侧分别设有补气接口和抽气接口。汽封系统通过汽封压力调整装置,可使汽轮机在满足高集成化要求的前提下,利用汽缸漏汽,实现汽封压力变工况快捷全自动控制,增强了汽轮机装置的智能化、自动化程度,为后续机组全自动操纵、机旁无人化操作打下基础。(The invention relates to a steam seal pressure adjusting device for a marine steam turbine, which comprises a shell, a slide valve, a piston, a slide rod, a sleeve and a servomotor, wherein the servomotor is fixedly connected with the shell; the upper end of the sleeve is provided with a connector connected with a steam seal balance system, the lower end of the sleeve is provided with an air inlet, the middle part of the sliding rod is provided with a reducing shaft which contracts inwards, and the reducing shaft is arranged in the air inlet at the lower end of the sleeve; the two sides of the upper part of the shell are respectively provided with an air supply interface and an air exhaust interface. The steam seal system can make the steam turbine meet the high integration requirement by using the steam leakage of the cylinder on the premise of meeting the high integration requirement, thereby realizing the quick and full-automatic control of the variable working condition of the steam seal pressure, enhancing the intelligent and automatic degree of the steam turbine device and laying a foundation for the full-automatic control and unmanned operation beside the machine of the follow-up unit.)

1. The utility model provides a vapor seal pressure adjusting device for marine steam turbine, includes casing, slide valve, piston, slide bar, sleeve, servomotor and casing fixed connection, its characterized in that: the piston of the servomotor is connected with a slide valve into a whole through a slide rod, the upper part of the shell is connected with a sleeve, the slide valve is connected in the sleeve in a matching way, the side surface of the lower part of the sleeve is provided with a window, and the window is communicated with an exhaust port on the side surface of the sleeve; the upper end of the sleeve is provided with a connector connected with a steam seal balance system, the lower end of the sleeve is provided with an air inlet, the middle part of the sliding rod is provided with a reducing shaft which contracts inwards, and the reducing shaft is arranged in the air inlet at the lower end of the sleeve; and both sides of the upper part of the shell are respectively provided with an air supplementing interface and an air exhaust interface.

2. The steam seal pressure adjusting apparatus for a marine steam turbine according to claim 1, characterized in that: the steam seal pressure adjusting device for the marine steam turbine is installed in a steam seal system, is connected with a steam seal balance system through an upper end port of a sleeve, is connected with a gas supplementing system through a gas supplementing port, is connected with a steam seal air exhaust system through an air exhaust port, is connected with a condenser through an air exhaust port, is used for controlling the pressure of the steam seal balance system to be micro-positive pressure, and is used for performing steam supplementing or steam exhausting actions through a steam valve in the steam seal system through the action of an oil-operated engine, so that the self-balance of the steam seal system is ensured.

3. The steam seal pressure adjusting apparatus for a marine steam turbine according to claim 1, characterized in that: the steam seal system adopts a closed-loop control system, an integrated embedded controller is used as a control core, the balance pressure and the displacement of the steam seal system are acquired in real time through an intelligent board card, analysis and comparison operation is carried out according to the displacement of the servomotor fed back by the LVDT and real-time data parameters of the pressure, a fuzzy PID algorithm is adopted for control, a positive/negative offset signal is output after operation and comparison, the signal acts on an electro-hydraulic servo valve for controlling the servomotor, and the electro-hydraulic servo valve acts to drive a piston of the servomotor to move up and down so as to keep the balance pressure of the steam seal system constant.

Technical Field

The invention relates to a steam seal system of a condensing steam turbine for a ship, in particular to a steam seal pressure adjusting device.

Background

The steam seal system mainly prevents steam from leaking into a steam turbine installation site from a cylinder, simultaneously prevents air from leaking into the cylinder, influences the vacuum degree of a unit and leads to acceleration of equipment oxidation, and the other function of the steam seal system is to recover high-pressure steam leakage of a high-pressure regulating valve and a steam turbine high-pressure steam seal, recover heat and improve the heat efficiency of the two-loop system.

A land steam turbine steam seal system is uniformly designed by a two-loop system with the aim of improving the circulating heat efficiency as shown in figure 1, recovers high-pressure regulating valves and high-pressure steam seal leakage, and supplements steam for a low-pressure steam seal of a steam turbine B through an electric steam supplement regulating valve (steam seal pressure regulation A) and a temperature-reducing water spraying device, so that self-balance is realized. Simultaneously, the gas-steam mixture pumped by the air pumping system is fed into the heat exchanger, so that the heat efficiency of the system is improved. The marine steam turbine is in lack of space, the installation requirement of a narrow space is considered, a steam seal system mainly adopts a pressure equalizing box structure to adjust steam seal pressure, the pressure equalizing box is used for compensating the regulating valve and high-pressure steam seal leakage steam to a low-pressure steam seal, and meanwhile, the pressure equalizing box is provided with a steam compensating pipeline to provide high-pressure steam required when self-balancing is insufficient.

The marine steam seal system can improve the cycle thermal efficiency if the design of the land steam seal system is consulted, but corresponding equipment needs to be added, the complexity of the system is increased, and meanwhile, the installation and maintenance difficulty is higher. The steam seal balancing box is easy to install, the structural form is relatively simple, manual intervention is needed when the working condition of the steam turbine changes, and the automation degree is low.

Disclosure of Invention

In order to improve the utilization rate of steam leakage in the marine steam turbine, enable the steam turbine to realize self-balance of a steam seal system and improve the automation degree, the invention provides a marine steam seal pressure adjusting device, and the structural device has the design advantages of structural integration, self-adaption of the steam seal system under variable working conditions, no steam leakage of the steam turbine and the like.

The technical scheme adopted by the invention for solving the technical problems is as follows: a steam seal pressure adjusting device for a marine steam turbine comprises a shell, a slide valve, a piston, a slide rod, a sleeve and a servomotor, wherein the servomotor is fixedly connected with the shell; the upper end of the sleeve is provided with a connector connected with a steam seal balance system, the lower end of the sleeve is provided with an air inlet, the middle part of the sliding rod is provided with a reducing shaft which contracts inwards, and the reducing shaft is arranged in the air inlet at the lower end of the sleeve; and both sides of the upper part of the shell are respectively provided with an air supplementing interface and an air exhaust interface.

Furthermore, the steam seal pressure adjusting device for the marine steam turbine is installed in the steam seal system, is connected with the steam seal balance system through the upper end port of the sleeve, is connected with the air supplement system through the air supplement port, is connected with the steam seal air exhaust system through the air exhaust port, is connected with the condenser through the air exhaust port, is used for controlling the pressure of the steam seal balance system to be micro-positive pressure, and is used for performing steam supplement or steam exhaust actions through the oil-actuated machine so as to ensure the self-balance of the steam seal system.

Further, a closed-loop control system is adopted in the steam seal system, an integrated embedded controller is used as a control core, the balance pressure of the steam seal system and the displacement of the servomotor are collected in real time through an intelligent board card, analysis and comparison operation is carried out according to the displacement of the servomotor fed back by the LVDT and real-time data parameters of the pressure, fuzzy PID algorithm control is adopted, a positive/negative deviation value signal is output after operation and comparison, the positive/negative deviation value signal acts on an electro-hydraulic servo valve for controlling the servomotor, and the electro-hydraulic servo valve acts to drive a piston of the servomotor to move up and down so as to keep the balance pressure of the steam seal system constant.

The invention has the beneficial effects that:

the steam seal system can make the steam turbine meet the high integration requirement by using the steam leakage of the cylinder on the premise of meeting the high integration requirement, thereby realizing the quick and full-automatic control of the variable working condition of the steam seal pressure, enhancing the intelligent and automatic degree of the steam turbine device and laying a foundation for the full-automatic control and unmanned operation beside the machine of the follow-up unit. Meanwhile, the function of manual control is kept, the normal work of the steam turbine can be ensured when a fault occurs, and the operation stability and the safety reliability of the steam turbine generator unit are improved.

Drawings

FIG. 1 is a diagram of a prior art vapor seal system;

FIG. 2 is a front view of the seal pressure adjustment assembly of the present invention;

FIG. 3 is a cross-sectional view taken along line A-A of FIG. 2;

FIG. 4 is a diagram of a vapor seal system employing the apparatus of the present invention;

FIG. 5 is a block diagram of the control principle of a steam seal system employing the apparatus of the present invention;

FIG. 6 is a diagram of the operating state of the gland pressure regulating device of the present invention;

wherein: (a) large amount of air supplement, (b) small amount of air supplement, (c) small amount of exhaust, (d) large amount of exhaust.

Detailed Description

The invention is further described with reference to the following figures and examples.

As shown in fig. 2 and 3, the steam seal pressure adjusting device for marine steam turbine of the present invention is mainly assembled by a housing 1, a slide valve 2, a piston 3, a slide rod 4, a sleeve 5, a DDV valve, a servomotor, an LVDT device, etc. While the servomotor is bolted to the housing 1, the piston 3 of the servomotor is connected to the slide valve 2 via the slide rod 4 to move up or down. The upper part of the shell 1 is connected with a sleeve 5, a slide valve 2 is connected in the sleeve 5 in a matching way, the side surface of the lower part of the sleeve 5 is provided with a window, and the window is connected with a condenser through an exhaust port d on the side surface of the sleeve 5; the lower end of the sleeve 5 is provided with an air inlet, the middle part of the slide rod 4 is provided with a reducing shaft which contracts inwards, and the reducing shaft is arranged in the air inlet at the lower end of the sleeve 5; and both sides of the upper part of the shell 1 are respectively provided with an air supplementing interface b and an air exhaust interface a, wherein the air supplementing interface b is connected with an air supplementing system, the air exhaust interface a is connected with a steam seal air exhaust system, and an upper end interface c of the sleeve 5 is connected with a steam seal balance system.

As shown in fig. 4, the vapor seal pressure adjusting device K is connected to the vapor seal pumping system, the vapor seal air supply system, the vapor seal balancing system and the condenser at the same time. The pressure at the position I of the steam seal system is controlled to be micro-positive pressure, and the steam valve performs steam supplementing or steam discharging actions through the action of the servomotor, so that the self-balance of the steam seal system is ensured.

As shown in fig. 5, a closed-loop control system is adopted in the steam seal system, an integrated embedded controller is used as a control core, the balance pressure and the displacement of the steam seal system are acquired in real time through an intelligent board card, analysis and comparison operation is carried out according to the displacement fed back by the LVDT and real-time data parameters of the pressure, a fuzzy PID algorithm is adopted for control, a positive/negative offset signal is output after operation and comparison, the positive/negative offset signal acts on an electro-hydraulic servo valve, and the electro-hydraulic servo valve acts so as to drive the high-pressure oil motor to act and move up/down to keep the balance pressure of the steam seal system constant.

When the steam pressure in the steam sealing system is lower than a set value, the controller sends a signal instruction to the servo valve, and the electro-hydraulic servo valve acts, so that the high-pressure oil motor is driven to act to enable the piston to move downwards. The slide valve also moves downwards, the side M of the slide valve reduces the opening of the window of the sleeve 5 or completely covers the window, so that the steam discharge to the condenser is reduced or completely interrupted, and the steam valve of the air make-up system makes up steam through the air make-up interface via the side K of the valve rod 4 and the air inlet at the lower end of the sleeve 5 (as shown in fig. 6 (b) a small amount of steam make-up condition). At the moment, the steam pressure in the steam seal system reaches a normal value, and the high-pressure servomotor reaches a new balance position to keep the pressure stable.

As the vapor pressure continues to decrease in the vapor lock system, the piston continues to move downward. At this time, the valve rod 4 opens the air inlet at the lower end with its own edge K (as shown in fig. 6 (a) under the condition of mass steam supplement), and supplies new steam into the steam seal balance system until the normal steam pressure is restored in the system, and the high-pressure oil engine reaches a new balance position.

When the steam pressure in the steam sealing system is higher than a set value, the controller sends an instruction to the servo valve, and the electro-hydraulic servo valve acts, so that the high-pressure oil motor is driven to act to enable the piston to move upwards. The slide valve also moves upwards, the edge M of the slide valve increases the opening degree of the window of the sleeve 5 (such as (c) a small amount of steam exhaust working condition and (d) a large amount of steam exhaust working condition in fig. 6), the steam exhausted to the condenser is increased until the steam pressure in the steam seal system reaches a normal value, the high-pressure oil engine reaches a new balance position, and the pressure is kept stable.