One Question per Day: Methanol Technology Exchange Edition 20180419
Thread Content
Learn from the advanced practices of the *Brothers section; there are prizes for correct answers – every response earns a reward, allowing us to grow and mature through these Q&A sessions. Short answer: Classification of end-face groove shapes for dry gas seals. The groove patterns on the dry gas seal end face are mainly divided into two categories: single helix direction and double helix direction. 1. Single-direction grooved types are used only in units that rotate in one direction; they generate an opening force only in the desired rotation direction. If rotated in the opposite direction, a negative opening force is produced, which can lead to damage to the seal. However, compared to grooves with dual rotation directions, it can generate a greater opening force and gas film stiffness, resulting in higher stability and more reliable prevention of end-face contact. Therefore, it can also be used at very low speeds and with high vibration. It is most commonly used in current compression units. 2. The double-direction grooved type has no requirement regarding rotation direction; it can be used in both forward and reverse rotation modes. The reversal of the unit will not cause damage to the seal. Its application range is wider than that of a single-direction groove, but its stability and interference resistance are inferior to those of a single-direction groove.
The groove patterns on the dry gas seal end face are mainly divided into two categories: single helix direction and double helix direction. 1. Single-direction grooved types are used only in units that rotate in one direction; they generate an opening force only in the desired rotation direction. If rotated in the opposite direction, a negative opening force is produced, which can lead to damage to the seal. However, compared to grooves with dual rotation directions, it can generate a greater opening force and gas film stiffness, resulting in higher stability and more reliable prevention of end-face contact. Therefore, it can also be used at very low speeds and with high vibration. It is most commonly used in current compression units. 2. The double-direction grooved type has no requirement regarding rotation direction; it can be used in both forward and reverse rotation modes. The reversal of the unit will not cause damage to the seal. Its application range is wider than that of a single-direction groove, but its stability and interference resistance are inferior to those of a single-direction groove.
The groove patterns on the dry gas seal end face are mainly divided into two categories: single helix direction and double helix direction. 1. Single-direction grooved types are used only in units that rotate in one direction; they generate an opening force only in the desired rotation direction. If rotated in the opposite direction, a negative opening force is produced, which can lead to damage to the seal. However, compared to grooves with dual rotation directions, it can generate a greater opening force and gas film stiffness, resulting in higher stability and more reliable prevention of end-face contact. Therefore, it can also be used at very low speeds and with high vibration. It is most commonly used in current compression units. 2. The double-direction grooved type has no requirement regarding rotation direction; it can be used in both forward and reverse rotation modes. The reversal of the unit will not cause damage to the seal. Its application range is wider than that of a single-direction groove, but its stability and interference resistance are inferior to those of a single-direction groove.