(Daily Question) Coal-to-oil and olefins forum, April 7, 2018
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3.jpg Participation: Prize of 5 Wealth； Correct answer: Reward of 10 wealth points ； Note: This post is valid for 48 hours. Question: (DMTO) Olefin separation unit: Why cannot the propylene refrigeration compressor be rotated electrically for an extended period of time? (1) The bearings of the compressor unit are dynamic pressure bearings. (2) Dynamic pressure bearings rely on the rotational speed of the shaft itself to drive lubricating oil from areas with larger gaps to areas with smaller gaps, thereby creating a dynamic pressure oil film that supports the bearings and separates the shaft from the bearing surfaces ； (3) Electric barring involves the rotation of the rotor at low speeds, making it difficult to form a dynamic pressure oil film; this leads to dry friction between the bearings and bearing shells. Prolonged use of electric barring can damage the bearings and bearing shells. Note: The answer will be announced automatically in two days!
The bearings of the propylene refrigeration compressor unit are dynamic pressure bearings； A hydrodynamic bearing uses the rotational speed of the shaft itself to drive lubricating oil from areas with larger gaps to areas with smaller gaps, thereby creating an oil wedge that generates a hydrodynamic oil film. This oil film supports the bearing and separates the shaft from the bearing bushes ； When using electric barring to rotate the rotor, it turns at low speeds, making it difficult to form a dynamic pressure oil film; this results in dry friction between the bearings and bearing shells. Prolonged use of electric barring can damage the bearings and bearing shells.
Why can’t the compressor be rotated electrically for a long time? Answer: The bearings in the compressor units of ethylene plants are dynamic pressure bearings. These bearings rely on the rotational speed of the shaft to move lubricating oil from areas with larger gaps to areas with smaller gaps, thereby creating an oil wedge that generates a dynamic pressure oil film which separates the shaft from the bearing shells. When the compressor is rotated electrically, the rotor rotates at a low speed, and it is not possible to form such a dynamic pressure oil film; as a result, dry friction occurs between the shaft and the bearing shells. Prolonged electric rotation can cause damage to the shaft and the bearing shells.
(1) The bearings of the compressor unit are dynamic pressure bearings. (2) Dynamic pressure bearings rely on the rotational speed of the shaft itself to drive lubricating oil from areas with larger gaps to areas with smaller gaps, thereby creating a dynamic pressure oil film that supports the bearings and separates the shaft from the bearing surfaces； (3) Electric barring means that the rotor rotates at low speeds, making it difficult to form a dynamic pressure oil film; this leads to dry friction between the bearings and bearing shells. Prolonged use of electric barring can damage the bearings and bearing shells
(1) The bearings of the compressor unit are dynamic pressure bearings. (2) Dynamic pressure bearings rely on the rotational speed of the shaft itself to drive lubricating oil from areas with larger gaps to areas with smaller gaps, thereby creating a dynamic pressure oil film that supports the bearings and separates the shaft from the bearing surfaces； (3) Electric barring means that the rotor rotates at low speeds, making it difficult to form a dynamic pressure oil film; this leads to dry friction between the bearings and bearing shells. Prolonged use of electric barring can damage the bearings and bearing shells
Since the bearings of the compressor units in the ethylene plant use dynamic pressure bearings； The so-called hydrodynamic bearing relies on the rotational speed of the shaft itself to drive lubricating oil from areas with larger gaps to areas with smaller gaps, thereby creating an oil wedge that generates a hydrodynamic oil film which supports the bearing and separates the shaft from the bearing bushings ； Electric barring involves the rotation of the rotor at low speeds, which makes it difficult to form a dynamic pressure oil film; as a result, dry friction occurs between the bearings and bearing shells. Prolonged use of electric barring can damage the bearings and bearing shells.
(1) The bearings of the compressor unit are dynamic pressure bearings. (2) Dynamic pressure bearings rely on the rotational speed of the shaft itself to drive lubricating oil from areas with larger gaps to areas with smaller gaps, thereby creating a dynamic pressure oil film that supports the bearings and separates the shaft from the bearing surfaces； (3) Electric barring means that the rotor rotates at low speeds, making it difficult to form a dynamic pressure oil film; this leads to dry friction between the bearings and bearing shells. Prolonged use of electric barring can damage the bearings and bearing shells
The bearings of the propylene refrigeration compressor unit are dynamic pressure bearings； A hydrodynamic bearing uses the rotational speed of the shaft itself to drive lubricating oil from areas with larger gaps to areas with smaller gaps, thereby creating an oil wedge that generates a hydrodynamic oil film. This oil film supports the bearing and separates the shaft from the bearing bushes ； When using electric barring to rotate the rotor, it turns at low speeds, making it difficult to form a dynamic pressure oil film; this results in dry friction between the bearings and bearing shells. Prolonged use of electric barring can damage the bearings and bearing shells.
(1) The bearings of the compressor unit are dynamic pressure bearings. (2) Dynamic pressure bearings rely on the rotational speed of the shaft itself to drive lubricating oil from areas with larger gaps to areas with smaller gaps, thereby creating a dynamic pressure oil film that supports the bearings and separates the shaft from the bearing surfaces； (3) Electric barring involves the rotation of the rotor at low speeds, making it difficult to form a dynamic pressure oil film; this leads to dry friction between the bearings and bearing shells. Prolonged use of electric barring can damage the bearings and bearing shells.
Since the bearings of the compressor units in the ethylene plant use dynamic pressure bearings； The so-called hydrodynamic bearing relies on the rotational speed of the shaft itself to drive lubricating oil from areas with larger gaps to areas with smaller gaps, thereby creating an oil wedge that generates a hydrodynamic oil film which supports the bearing and separates the shaft from the bearing bushings ； Electric barring involves the rotation of the rotor at low speeds, which makes it difficult to form a dynamic pressure oil film; as a result, dry friction occurs between the bearings and bearing shells. Prolonged use of electric barring can damage the bearings and bearing shells.
(1) The bearings of the compressor unit are dynamic pressure bearings. (2) Dynamic pressure bearings rely on the rotational speed of the shaft itself to drive lubricating oil from areas with larger gaps to areas with smaller gaps, thereby creating a dynamic pressure oil film that supports the bearings and separates the shaft from the bearing surfaces； (3) Electric barring means that the rotor rotates at low speeds, making it difficult to form a dynamic pressure oil film; this leads to dry friction between the bearings and bearing shells. Prolonged use of electric barring can damage the bearings and bearing shells