The stem to point out the valve position


Different types of valves can be found: gate, globe, plug, ball, butterfly, check, diaphragm, pinch, pressure relief, control valves etc. Each of these types features a number of models, each with some other features and functional capabilities. Some valves at are self-operated while other people manually or through an actuator or pneumatic or hydraulic is operated.

There a wide range of valve designs, types and models, which has a wide range of industrial applications. All satisfy a number of of the functions identified above. Valves can be very expensive items, which is important that a proper valve is specified to the function, and must be constructed on the correct material to the process liquid.Regardless of type, all valves hold the following basic parts: your body, bonnet, trim (internal elements), actuator, and packing. The basic aspects of a valve are illustrated within the image within the right.

Rising stems are fixed to your gate and in addition they rise reduce together because valve is operated, providing a visual indication with the valve position and making it possible to grease the stem. A nut rotates round the threaded stem and moves it. This type is just suitable for above-ground installation.

Non-rising stems are threaded in to the gate, and rotate while using wedge rising and lowering within the valve. They undertake less vertical space since stem is kept from the valve body. AVK offers gate valves using a factory-mounted indicator for the upper end with the stem to point out the valve position. Gate valves with non-rising stems are well suited for both above-ground and underground installations.

The most of AVK’s range are intended with non-rising stem, but we also offer gate valves with rising stem for water, wastewater and fire protection applications.

Before the resilient seated gate valve was introduced towards the market, gate valves that has a metal seated wedge were widespread. The conical wedge design and angular sealing devices of an metal seated wedge call for a depression within the valve bottom to make certain a tight closure. Herewith, sand and pebbles are embedded from the bore. The pipe system won't be completely free from impurities regardless how thoroughly the pipe is flushed upon installation or repair. Thus any metal wedge will in the end lose being able to be drop-tight.

A resilient seated gate valve incorporates a plain valve bottom allowing free passage for sand and pebbles from the valve. If impurities pass because valve closes, the rubber surface will close round the impurities even though the valve is closed. A high-quality rubber compound absorbs the impurities as being the valve closes, as well as the impurities will likely be flushed away if your valve is opened again. The rubber surface will regain its original shape securing a drop-tight sealing.

As maybe you have seen from the main Menu "Valves", you could find also details about several and sometimes applied valves in Petro and chemical industry.It can present you with an impression, and good understanding with the differences involving the various types of valves, and the way these differences change the valve function.






Jocelyn Stout



Add-on Type






Risk factor


QA Kickoff Status


QA Demo Status