The equipment used in the production, usage and storage of these chemicals must be regularly maintained and kept clean so that they can be safely used for long periods of time. Belleville washers, which derive their name from their resemblance to washers, are fast becoming the industry standard for maintaining a safe operating environment and reducing overall equipment maintenance costs. They have a high tensile strength, affordable pricing, and fairly easy maintenance requirements.
With modern technology comes stiffer economic and environmental regulations for manufacturers and plant operators. Maintaining efficiency is not only a cost-effective measure, but an integrity and corporate social responsibility issue. One of the common causes of fugitive emissions is improperly torqued bolts and fasteners. These can cause millions of dollars in property damage, financial loss, and even death. Belleville washers are designed to regulate gasket pressure and control bolt stress to prevent flange joint failures and leakage of fugitive emissions.
Belleville washers help in meeting these regulations by providing the required amount of clamping pressure to bolted connections in a more evenly distributed and continuous form. They are able to withstand very high temperatures of up to 1500° F. as well as extremely low temperatures of -330° F. This allows them to withstand bolt stress due to thermal expansion and contraction. They also provide nickel-chromium and stainless steel alloy washers that can withstand corrosion and causticity. These washers also contain spring energy to combat bolt creep, embedment, and gasket relaxation as well as vibrations that cause bolts to weaken. When selecting a the right belleville washer, several factors must be considered:
Diameter
A belleville washer that is bigger in diameter than the intended connection pad will reduce the clamping force leading to loose connections. Should you be unable to find a belleville washer with the correct diameter that you require, an engineer can customize one for you.
Torque
You must use the correct amount of force on the bolt to flatten the washer so that it clamps correctly. The torque used on the bolts must be equal to that used on the washers, give or take a few percentage points.
Finish
The finish or coating on the Belleville washer you select depends on the sort of petrochemicals that it will come into contact with and the environment under which the washer will be used. Although most connections only need a standard finish, you must take into account chemical reactions that may corrupt the washer’s utility. For example, hydrogen tends to cause brittleness in electroplated washers, which upon rigorous vibration will cause them to shatter.
Belleville washers must be properly installed under sanitary conditions so that they work correctly. Dirt and grime can introduce resistance while using the incorrect amount of torque can damage the washers or cause them to operate inefficiently.