Threaded globe valves
Fig. V320 — needle sleeve valve made of stainless steel EN 1.4401, graphite seal and pressure PN140. Fig. V321 — stainless steel shut-off valve EN 1.4301 PN16. Also available is a cast iron valve 15kch18p PN16.
The needle design provides more precise flow metering, while the shut-off valve primarily opens or closes the pipeline. Available diameters and prices are listed in the product cards.
When choosing, you need to compare not only the PN, but also the purpose of the valve, the operating temperature range, and the characteristics of a specific size.
For which environments are threaded valves suitable?
The working medium is determined by the material of the body, stem and seal. For V321, water, oil, gas, temperature up to +150 °C and PN16 are specified. V320 is intended for water, air, gas, steam, oil products and mildly aggressive media; PN140 and temperature up to +570 °C are declared.
Pressure and temperature are not considered independently: the mode depends on the environment and documentation. For heating, the coolant temperature is checked, and for gas or steam, the seals and regulatory requirements are checked. The characteristics of the cast-iron model are specified in the passport.
Design features of the shut-off valve
A gate, or shut-off valve, shuts off the flow by a moving element that is lowered onto a seat. The rotation of the flywheel is converted into a translational movement of the stem. In the closed position, the working element is pressed against the seat.
The valve requires several turns of the handwheel, so it changes the passage more smoothly, but creates more resistance. The shut-off model is not used for long-term adjustment without the manufacturer's permission. A needle valve is suitable for precise dosing.
The design of the housing may require a specific direction of movement of the medium. Therefore, before installation, check the markings on the housing and the manufacturer's installation diagram.
Spindle, spool and seal
The spindle or rod transmits the force from the flywheel. The spool moves relative to the seat and forms a passage. When closing, the sealing surfaces ensure tightness. Excessive force can damage the seat, so extensions are not used.
In the V320, the stem is made of EN 1.4401 steel and the seal is made of graphite. In the V321, the stem is made of EN 1.4301. The stuffing box and smoothness are checked according to the instructions.
How to choose a case material
Stainless steel is needed where corrosion resistance is important. EN 1.4301 is used in V321, and the more alloyed EN 1.4401 is used in V320. The steel grade is selected according to the composition of the environment.
A cast iron body is a practical solution for standard networks with appropriate pressure and temperature parameters. Brass and bronze are common in small diameter threaded fittings. The material cannot be replaced with an analogue without checking the design.
Advantages of coupling connection
The coupling valve is installed without flanges and takes up less space. The thread simplifies installation on small-diameter pipelines, and the detachable connection facilitates replacement or maintenance of the valve. For V321, the catalog contains sizes DN15–DN100, for cast iron 15kch18p — DN15–DN50, and V320 is presented in DN15.
During installation, check the thread size, clean the surfaces and use a compatible sealant. Hold the body with a suitable tool, without transferring force through the handwheel. If there is an arrow, install the valve in the direction of flow.
Buy threaded valves with delivery across Ukraine
You can order threaded valves at UKSPAR with delivery across Ukraine. For selection, please inform us of the type of working medium, maximum pressure and temperature, required diameter, pipeline material and thread parameters.
Experts will help you compare needle and shut-off options and check materials. Accurate selection ensures the tightness of the assembly and the predicted service life of the fittings.