Can the mixer in the polymerization reactor run idle?
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This post was last edited by wang*neng on 2010-11-18 23:38. Hello everyone: What impact does idling rotation of the mixer in the polymerization tank have on the tank? The instructions that come with polymerization reactors generally state that the agitator must not run idle! Why does CHISSO’s technology cause it to run idle? Moreover, the polymerization reactors at Tianjin Daguhua have been in use for over a decade; as far as I know, the mixing systems in them have never failed. I’m not sure how reliable those made in China are
Idling has no effect on the polymerization reactor; it can operate in an idling mode. It is estimated that the so-called inability to run idle means it cannot be started without lubrication for the mechanical seal.
The so-called idling operation of the mixer refers to its operation with no material filling the mixing blades. Since the heat generated by the rotation of these blades during idling is difficult to dissipate, prolonged idling of the mixer can have adverse effects on it.
I agree with what the person in post 2 said. I think running the machine idly should have an adverse effect on the reducer, but I’ve never encountered any actual cases of this
Thank you all, but I just want to know what the impact is? Should I ask about the machinery instead?
This post was last edited by missile80 on 2010-11-19 09:29. Whether a mixer allows idling is determined by its design. When a rigid structure design is used, the mixer is allowed to run idle for a short period of time. In the design of rigid structures, the balancing effect of the liquid’s resistance on the mixer is not taken into account when calculating the shafting. Therefore, the calculation conditions remain valid even in the absence of such liquid resistance; of course, having this liquid resistance makes the design more secure. When a flexible structure design is used, it is absolutely not allowed to be operated without load; even a slight movement can cause the entire mixing shaft to break off. In the design of flexible structures for calculating shafting systems, the resistance exerted by the liquid on the stirrer is also taken into account as a factor in the calculations; without this resistance, the calculations for the entire shafting system become invalid. When the mixer passes through the critical speed range during startup, the shaft may be suddenly thrown off due to resonance; such an event usually occurs in an instant. Therefore, free rotation is not allowed in the design of flexible structures; at the same time, it is necessary to ensure that the liquid level is above the stirrer by a certain distance. The main consideration is that vortices are formed once stirring begins, and the stirrer must not be exposed to these vortices.
Reply to 6# missile80: If a flexible design is used, wouldn’t that impose too high requirements on operation? In fact, it is generally necessary to conduct a no-load test of the equipment before driving it in a factory.
This post was last edited by clq20040107 on 2010-11-20 at 11:43. Has the original poster seen any manufacturer’s instructions for agitator tanks that include a requirement to prohibit running the agitator idly? In fact, the stirring in the polymerization reactor can run idle; it’s just necessary to keep the oil supply system and the seal water in operation while it is rotating. However, prolonged idling causes the mixer to rotate for too long, which makes it easy for the bearings to bend due to the centrifugal force generated by rotation, thereby leading to damage to the mixer. Additionally, I disagree with the claim that the connection method of the mixer upstairs determines whether it can run idle; the coupling used for the mixer in the polymerization reactor is a flexible connection. A rigid coupling does not have the ability to compensate for relative misalignment between the shafts it connects, nor does it possess shock-absorbing properties. It should only be used when the load is stable, the rotational speed is steady, and it can be ensured that the relative offset between the two axes connected together is minimal.
Reply to 8# clq20040107: Of course I saw it. How could I say I didn’t see it if I had? Is there such a phenomenon as idle stirring during operation, other than CHISSO’s technology?
This post was last edited by clq20040107 on 2010-11-21 09:05. Check the design specifications for the mixer – as long as they meet the required standards, that’s fine. When applying the anti-adhesion agent, it is beneficial to start the mixer in order to improve the coating effect
It can run idly, but not for too long, as idling can affect the lifespan of the device. If testing it, clean water can be used; add the material only after everything has been adjusted properly. These are minor issues, and it is recommended to avoid idling as much as possible!