Turbine startup
Thread Content
Recently, the steam turbine in our company’s catalytic unit experienced a cascading shutdown due to excessive vibration caused by water carryover in the steam. After 15 minutes, the temperature and pressure of the medium-pressure superheated steam reached the conditions required for operation; the shift supervisor and the crew started up the unit. By the time I arrived at the workshop an hour later, the compressed rich gas had already been connected to the stabilization system. I inquired about the entire process and identified the following issues: 1. Since the compressor-turbine unit does not have an electric barring gear, and considering that the shutdown time was short as well as no abnormal noises were heard during the coasting period, the unit was not rotated using the barring gear before being started up. 2. During the startup of the steam turbine, the exhaust steam is not first vented at the turbine outlet and then fed into the low-pressure pipeline network after reaching a certain rotational speed. Instead, it starts directly. The workshop wanted to punish them for not following the unit startup procedures, but their explanation was that they had done it this way before and no problems had ever occurred. Help analyze whether they should be punished?
I think punishment should be imposed, in accordance with the regulations; otherwise, what if similar problems arise in the future? The level of punishment can be a bit lighter.
Don’t hastily talk about penalties. By observing the vibration trends during startup, and if the vibration levels are not high, then by checking parameters such as steam temperature, pressure, and flow rate, it is possible to develop a thermal startup method suitable for that specific unit – thereby creating a new approach to saving energy and reducing consumption. You should know that not venting it saves a large amount of steam condensate water
A short duration is fine; but if it goes on for too long, it won’t work.