Have you ever encountered leaks in your piping system due to flange problems?
Flanges in pipelines are critical components in any static sealing equipment (together with fasteners and gaskets, they form the sealing triangle), so they require proper care and maintenance in order to ensure tight sealing and prevent unwanted leakage.
If in a previous post we talked about why flat joint failures occur, In this article, we focus on the most common causes of flange problems in pipelines: under-tightening. Read on and we will tell you how to identify this problem and the practical solutions to solve it.
Index
What is under-tightening and why is it a problem?
At Epidor Seals and Rubber Technology we know that more than 60% of premature flange joint failures are the result of insufficient tightening of the flange bolts during assembly, causing fluid leakage, which escapes to the outside of the flanged joint or penetrates in the event of a vacuum.
When flanges are not sufficiently tightened, liquids or gases can leak through the gaskets, and this can lead to a loss of pressure in the system, environmental contamination and safety risks for facilities and personnel. It is crucial to address this problem quickly and effectively to avoid negative consequences.
Why is there insufficient tightening of flanges on pipelines?
The fact that flanges are not sufficiently tightened on pipelines (or mis-tightening) can occur due to several factors: the main reason for under-tightening the cable ties is because of using unsuitable tools for tightening (dynamometric or general torque control tools are required).
But it may also be the case that the flanges on pipes are under-tightened due to other factors:
- Due to lack of experience in the assembly of flanges on pipelines or due to a bad assembly (tightening sequence, bolts and nuts...).
- Due to the use of flanges or other low quality materials.
- Due to long-term loosening (due to vibrations, cycles, insufficient preload...).
Tools for proper installation of flanges on pipelines
After years of experience in the industry as a specialists in sealing solutions, At Epidor Seals and Rubber Technology, we know that poor tightening of flange bolts often occurs because we do not use torque tools or torque control tools in general, which allow us to guarantee the proper tightening torque on each flange.
In addition, in the case of working with thick bolts, the torque required for proper tightening may be beyond what can reasonably be achieved with simple hand tools, such as open-end wrenches or ratchet wrenches, making it even more evident that specific tools are required to install flanges on pipelines.
In these cases, it is not only advisable, but necessary, to use torque multipliers or other tools that allow us to apply the required high tightening torques in an easy, efficient and controlled manner.
Recommendations for installation of sealing flanges
In addition to using the appropriate tools mentioned above, it is important to tighten the screws in the correct sequence and in several stages with final torque check: the correct way to tighten the bolts is to tighten them in a cross pattern, to ensure that the flanged joint closes evenly. In this way we avoid that one bolt is unloaded when tightening adjacent bolts.
On the other hand, a practice that is not recommended when using flange tools on pipelines is that IMPACT GUNS MUST NEVER BE USED to tighten flange bolts..
In any case, at Epidor Seals and Rubber Technology we take care of offering advice on the correct tightening torque for any installation, We calculate the tightening intensity with our calculation tools. In addition, we provide any facility maintenance manager with the necessary tools (torque wrenches, torque multipliers, etc.), as well as advice on their selection.
Now you know the importance of the correct tightening of flanges on pipes, and what are the consequences of improperly tightening a flange for sealing. In addition, you also know that Epidor SRT has the right tools and practical solutions to avoid future problems related to insufficient tightening of pipe flanges. This way you will be able to keep your systems in optimal operating conditions.
In addition, Epidor Seals and Rubber Technology offers practical courses on flange gasket selection and assembly, for users and engineers, based on EN1591-4 training. We also send our engineers to the plants that require it. As an example and to provide you with more information, we invite you to read the following article related to one of our training for flange gasket installers.Do you need assistance with your piping systems or do you have any questions about flange tightening? Don't hesitate to contact the Epidor Seals and Rubber Technology Technical Department.