Emergency shut-off valve works

Emergency shut-off valve principle

The basic requirements of the emergency shut-off valve to the valve are: close and fast, and fire safety structure. Although, in the conventional valve, the metal sealing ball valve with high sealing performance is the best choice. When a soft seal structure is used, it must be a fire safety type structure to ensure that after the failure of the soft seal structure, hazardous materials can still be cut off without flowing into the accident site.

Emergency cut-off valve Emergency cut-off valve actuator, now the power source can have the following choices: electric, pneumatic, hydraulic three.

(1) Motors of electric actuators should normally choose fireproof and explosion-proof structures. The cables are fire-retardant or fire-resistant. Considering the influence of the motor insulation material, high-humidity sites should not be used.

1. Explosion-proof electric actuator, with its unique and novel design, advanced and superb technical process, high-quality imported parts, and scientific and rigorous quality testing, the valve automation at home and abroad has a unique style. Explosion-proof electric actuator actuators will push the precision, digitization, and intelligence of valve electric devices to a new stage and become a rising star in the automation control industry.

2. Actuator adopts imported micro-switch (Omron) and bearing (NSK) from origin. Our cabinet is manufactured by CNC machining center. All parts are processed by CNC machine tools to ensure machining accuracy, assembly accuracy, and maximum Reducing friction and increasing transmission efficiency enabled us to introduce a fast switching type: 2.8 seconds, 300 Nm. This product is currently the smallest domestic electric actuator with the largest output torque and the fastest speed.

3. The implementing agency can directly receive the 4-20mADC or 1～5VDC control signal outputted by the computer or industrial instrument, and perform the intelligent step adjustment (PID adjustment) to the actuator drive motor according to the deviation of the valve position feedback signal and the set value. To achieve accurate positioning of the valve or other device opening matching with the actuator, and output the position feedback signal of 4-20mADC at the same time.

4, explosion-proof grade ExdII BT4, ExdII CT6, protection class IP67, NEMA4 and 6, with on-site manual hand wheel control device. The main features are: When no power is applied, the clutch handle can be manually operated.

(2) Pneumatic actuators The adequate supply of power air and the cooperation and lubrication of good cylinders and pistons are the key to normal operation of pneumatic actuators. Otherwise, there will be slacking and jamming.

1. The actuator and adjustment mechanism of the pneumatic actuator are a unified whole, and its actuators are film type, piston type, and rack and pinion type. The piston stroke is long and is suitable for occasions requiring greater thrust; while the diaphragm stroke pneumatic actuator is small and can only directly drive the valve stem. As the rack-and-pinion pneumatic actuator has the advantages of simple structure, large output thrust, stable and reliable operation, and safety explosion-proof, it adopts (compressed air, nitrogen) as the power source, and accepts distributed control system (DCS) and programmable controller ( PLC) and other switch signals, through the solenoid valve can achieve fast position control of the valve.

2. Pneumatic actuators can also be divided into two types: single-acting and double-acting: The actuator's switching action is driven by the air source, called (double acting). (Single-acting) switching action is only open action is driven by air, and closing action is by spring return.

3. The hydraulic actuators are not limited by more factors except that the hydraulic fluid is not corrosive and winter is not frozen. The system is simple and there is a trend of promotion and application.

The hydraulic actuator is a practical operation type product, and the actuator is equipped with a hydraulic actuator. Type: Normally closed, hand-operated oil pump supporting use. The hydraulic device is a driving device for opening and closing or adjusting the valve with hydraulic pressure. It consists of three parts: control, power and actuator. The power part is composed of hydraulic pump, oil tank and other parts to achieve reciprocating linear motion; the other is the hydraulic motor actuator to realize rotary motion.