In pipelines for adjusting the supply of hydraulic medium mounted two-way valve. Depending on the material of manufacture it may be used for liquid and gaseous working media, at a pressure up to 40 atm, and a temperature of over 150 degrees.
The operating principle of the two-way tap
The main feature of the two-way fitting is that the adjustment of the volume flow can be made only in the flow direction of the arrow indicated on the housing. Adjusting the flow in the reverse direction is not performed, a connection may lead to failure of the device.
Changing the flow rate by turning or lifting of the locking element which is made tap handle, or by an electromagnetic actuator.
When fully closed the locking element fluid flow stops, and provides complete sealing system for crane. That the various abrasive particles could damage the mirror surface of constipation, we recommend installing a filter in front of the entrance.
Features and types of two-way valves
Various commercially available models that differ in size, the manufacturing material, design of the locking element and the flow rate control type.
fitting design can not be collapsible, then it can not be repaired and it should be easy to replace in case of failure. Another option is a collapsible design, when you can try and replace the faulty part model. Drawing two-way assembly of such a crane and will give you complete information on the designation and implementation of the part.
Important! The fitting of this type changed only gaskets and seals. If faulty locking ball or stock, completely change the entire device.
Differences in the type of connection systems
By type of connecting devices come in the following versions:
- Coupling. They are used for small diameter pipelines. On both sides of the fitting sliced internal or external thread for connection to the conduits. If necessary, you can easily replace a comparable device.
- Flanged. Used for pipes of large size and volume of supply. To install the pipeline flanges are welded, the same size as on the fitting. For sealing compounds are used paronita gasket, or at a high temperature, asbestos. In case of failure can be easily replaced.
flange fitting - Welded. It is rarely used, a compound obtained by a one-piece, replacing a piece of pipe to be cut with the apparatus. The advantage of this type of compound is the absolute tightness of the weld.
- Mounting. Threaded end is screwed into the plate block hydraulic control device of working bodies of the building or road cars.
Differences in body material
Depending on the operating environment, temperature and pressure valves are made of the following materials:
- Brass - used at pressures up to 16 atm. Suitable for cold water systems and other working environments having a temperature not higher than 60º C.
- Cast iron - can withstand pressure up to 25 atm. Currently, cast iron fittings are used rarely. They are used instead of steel, which are superior to them in many respects.
- Steel - pressure up to 40 atm. Can be applied at high temperatures over 150 º C, but the stability must work at this temperature cooling system set radiator.
- Plastic, designed for low pressure. It is used for mounting plastic and polypropylene tubes. Gardeners use it to irrigate their plots.
- Particularly resistant stainless stainless steel fittings. Applied for corrosive environments, and the hydraulic system the working devices. Designed for high pressure over 100 bar and a working temperature of -60º C.
Constructive contrast devices
The shape of the enclosure are:
- straight, set on the straight pipe sections;
- angle, rotated by 90 degrees;
- dvuhventilnye, in the event that it is necessary to sum the two streams into one, when the valve assembly is installed with two valves.
Two-way fittings management mind:
- Adjustment is made by means of the handle. For large diameter piping is used with the flywheel gear for smooth regulation of flow.
Flywheel gear - With remote electric control. It can be of two types with an electromagnetic valve or the motor. The solenoid valve is mounted on the small-diameter valves, and motor on the main pipelines. Perhaps the smooth flow control and closing in an emergency.
Fitting with electromagnetic control - Adjustment with pneumatic actuator. A pneumatic cylinder mounted on the fitting by means of which, at an intake air opening or closing takes place. A disadvantage of such a system air line wiring required.
The locking elements of two-way valves
Brief description of the elements and types used are shown below:
- Ball shut-off element. It provides a complete seal when closed. flow path is produced by rotating the ball through 90 degrees, in some designs have an intermediate position of the ball, so fine adjustment feed is not possible.
- Conical or cylindrical vertical rod. It produces smooth adjustment of the flow, from 0 to maximum. However, it can not serve as a shut-off valve, due to leakage through the gate.
- Dvuhsedelchaty shutter. It is used for large volume flow, for separating the stream and smoothing turbulent phenomena arising. Also, do not use when you have to completely shut off the flow.
Where to apply two-way valves
Among of valves this type of device is the most used in many systems and equipment:
- In systems where it is necessary to control the temperature of the main water cooler is the control fitting. It regulates the flow of water to the heat exchanger. In such a device mounted solenoid operated valves. Management of water supply volume is performed automatically by a thermostat.
- In the oil and gas industry apply fittings to the housing and the spherical locking element in stainless steel, with a temperature range of -60 ° C... 240 ° C, and a pressure of 150 atm.
- In systems using the hot water supply fitting feed water is adjusted to consumers.
- Cranes are widely used in the food industry, for liquid products, air, supply air, steam, steel and many other industries.
Recommendations regarding the selection and installation of crane
Selection and installation of this unit is not too much difficulty, but it is better to first read the synopsis of recommendations:
- If you are installing threaded fittings, the thread on the crane shall comply with threaded on the tube, then you can do a minimum number of adapters.
- casing material must withstand the maximum temperature and pressure in the system.
- If necessary, completely block the flow, it is better to install ball-fitting, it is fully provided with equipment for leaks. If the valve is installed with the other locking element is to ensure the integrity of the system is necessary to install the shut-off valve fitting.
- The use of fittings designed for a lower pressure than the system is not allowed, it can lead to an emergency situation.
- When the two-way valve installed in remote places and there is a need of its adjustment, it is best to apply a valve with electric or pneumatic actuator.
The two-way valve like the regulator is used in many systems, whether gas or liquid in pipes. Widespread it has received thanks to the reliability of operation, ease of installation and the ability to easily remotely control the supply of the working environment.