Durability Increasing of Rotary Equipment
The reliability of every equipment is one of the most important tasks in any major industry. In oil industry, reliability influences on the stability of gathering, transportation and refining of oil and their products. The lower the reliability, the more failures happens and even accidents that could lead to more economic loss and technological problems.
In oil transportation, it's suggested to use a powerful centrifugal pump, with a reached value of 10 MWt (for oil pumps NM-10000-210), require careful attention. This type of equipment most of the time require great costs.
It's very important that Pumps provide a high reliability and durability in this industry. Engineers suggest a good method to provide high reliability and durability of equipment. Consisting on the following parts:
- Real-time monitoring of actual technical condition of the machine;
- Reduction of dynamic loads in a machine;
- Monitoring of life cycle parameters of a machine.
Real time monitoring of actual technical condition of the machine
Nowadays the technical condition of an equipment is controlled for a certain period of time, so it's normal to call maintenance according to the plan used. But this method, doesn't provide an actual information about the condition of the equipment. Some defects can occur rapidly and cause a lot of problems in work of the equipment and reduce its efficiency.
The monitoring system of actual technical condition with elements of frequency analysis is being developed by engineers to have a better monitoring of the equipment. This system use permanent vibration monitoring and processing vibration signals. It allows identification of defects in real time.
Reduction of dynamic loads in a machine via dynamic absorbers
Despite advantages vibration isolation, there's one general problem. By not reduce oscillation in a machine, it only reduce transmission of vibration to other objects. To reduce of transmission of vibration, is very important but it is necessary to reduce oscillation of a machine. One of the best ways to do it is to use dynamic absorber. To absorb is quite simple but effective facility. Consisting of a weight agent connected to an equipment with a help of spring.
The mass of the weight agent and stiffness of the spring has certain calculated value that provide the same natural frequency that frequency of the rotor of the machine. These allows the dynamic absorber oscillate in a resonance and consume energy of oscillation of the equipment. Simultaneous application of vibration isolator with quasi-zero stiffness and dynamic absorber allows reducing oscillations of the machine up to zero.
Reduction of dynamic loads in a machine via vibration isolators with quasi-zero stiffness
If a defect or a problem already exists in an equipment, it should be maximum reduced in one way application in vibration isolation system. The isolation between equipment and foundation allows the reduce of force and hence reduce negative effect of vibration on other equipment.
Nowadays one of the most perspective ways to provide high-quality vibration isolation is application vibration isolators with quasi-zero stiffness. It is such a vibration isolator that has special non-liner force characteristics providing low natural frequency and low dynamic stiffness. These parameters allows to avoid transfer dynamic force from a machine to foundation
On these days the most perspective ways to provide high-quality vibration isolation is application vibration isolators with quasi-zero stiffness. The vibration isolator has a special non-liner force characteristics to provide low natural frequency and low dynamic stiffness. Some parameters allow to avoid transfer dynamic force from a machine to foundation.
The installation scheme is represented on Fig. 3. The steel rings are assembled to the frame of the unit by welding. These rings allows vibration isolators to hold stable position. A support frame is jointed to the foundation. The supporting frame is a steel sheet, the length and width of which is equal to the dimensions of the unit frame. Note any hard links of machine with technological pipelines should be removed. Otherwise, machine continues to be rigidly connected to the foundation of the building and the efficiency of the use of vibration isolation system will be low. So, elastics joint in pipes and elastic supports should be used.
Steel rings for the vibration isolators are welded to the sheet. The support frame is installed by anchor bolts embedded in the foundation. Equipment continues to be rigidly connected to the foundation of the building and the efficiency of the use of vibration isolation system will be low. So, elastics joint in pipes and elastic supports should be used.
Monitoring of life cycle parameters of a machine
Analysis of life cycle parameters allows identifying hidden defects in details and identifying manufactures that produce equipment and detail with high probability of defects. It's possible to careful analyze the statistics of failures and accidents. These accidents are usually distributed due to classical low like.
The analysis of the statistics of failures in the whole industry of an enterprise allows them to get a general distribution of failures of a certain detail. Detailed analysis shows that in both cases most of failures appear after almost the same duration. If the corresponded equipment are produced by the same manufacturers, so it should be concluded that this manufacturer has a problem in manufacturing process that needs to be fixed. In this case, the defect equipment should be changed in advance.
Source: Durability Increasing of Rotary Equipment Based on Monitoring and Reducing Dynamic Loads