The Importance of stem for the valves

Jodith factory takes the stem as the one of the most important material for our valves in order to promise the quality. Stem of a Gate valve is very important.

In order to let you know how important the stem is, you can see the next passage.

The stem, which connects the handwheel and disk with each other, is responsible for the proper positioning of the disk. Stems are usually forged and connected to the disk by threaded or other techniques. To prevent leakage, in the area of the seal, a fine surface finish of the stem is necessary.

The stem roughness of valves matters the torque of the valves, and its machining andtreatment method decides the strength enduring the usage of service. 

See our gate valve rising stems as bellow:

Stems are classified as either: Rising Stem and Non Rising Stem

For a valve of the Rising Stem type, the stem will rise above the handwheel if the valve is opened. This happens, because the stem is threaded and mated with the bushing threads of a Yoke. A Yoke is an integral part from a Rising Stem valve and is mounted to the Bonnet.

For a valve of the non-Rising Stem type, there is no upward stem movement if the valve is opened. The stem is threaded into the disk. As the handwheel on the stem is rotated, the disk travels up or down the stem on the threads while the stem remains vertically stationary.

So pay attention to the stem when you order valves. It shall be seriously controlled too in production.