Rubber Bellow Mechanical Seal

A: Bellows Mechanical Seals are also known as non-pusher seals as they have a static secondary seal which stays in place against the shaft, sleeve or on the gland of the pump.

A: The primary function of bellows seal valves is preventing potentially harmful or toxic fugitive emissions which can negatively affect unprotected humans and the surrounding environment.

A: Improved Safety: Mechanical seals provide a high level of safety by preventing leaks and spills. They can handle high-pressure and high-temperature environments, ensuring that fluids are contained within the equipment. This reduces the risk of accidents, environmental damage and equipment failure.

A: The most common design types are Rubber Diaphragm, Rubber Bellows, O-Ring Mounted & PTFE Wedge.

A: The most common cause is dry running, where the pump operates without adequate lubrication. Dry running generates excessive heat and accelerates seal degradation. Other significant causes include improper installation and alignment issues.

A: A mechanical seal can fail wherever there's an O-ring or a gasket, as these weak points are most likely to leak. Failure could occur due to a worn O-ring. It could happen when dirt or other contaminants get between the seal faces. Or failure might ensue due to a design flaw.

A: Lubrication is necessary for proper mechanical seal installation. Lack thereof can damage o-rings or rubber bellows on the seal, causing them to tear, or roll. There are many options available, from petroleum jelly, to silicon grease, to special lubricants.

A: Gaskets are used to seal two components or flanges that have a flat surface. Seals are used to describe parts that are used between engine parts, pumps and shafts that rotate. Gaskets are used as static seals. When a seal is used between engine parts, pumps and shafts that rotate, it is described as a dynamic seal.

A: If a mechanical seal is leaking, restrain yourself from the natural tendency to tighten, and try loosening instead. Oftentimes this works.

A: Mechanical seals often leak because something changed about the operating conditions, such as pressure in the seal chamber, temperature around the shaft seal, pumped medium, speed, and shaft seal dimensions. Poor lubrication.

A: Mechanical seals are devices that are used to provide a seal at the point of entry or exit of a rotating shaft. Typically it is used to prevent the leakage of one high pressure fluid into a lower pressure fluid.

A: Check if your seal has a single, multiple or wave type spring. Wave types are used in compact pumps, while single is most commonly used. Another alternate to springs is metal bellow. The bellows are costlier and used in complicated seal applications.

A: Two common causes of a mechanical seal failure are excess vibration and misalignment of seal faces. Operators should be able to identify those reasons and do the correct maintenance when needed to ensure optimum productivity.

A: A mechanical seal has four components: a flat stationary seal face, a flat rotating seal face, a spring mechanism and a secondary elastomic seal. The two seal faces are pressed together by a spring mechanism. The seal faces are commonly carbon, ceramic or metal.

A: If a seal or gasket is worn out, you may notice fluid leaking around the seal. Cracked and worn seals/gaskets should be replaced as soon as possible.

A: Properly installed and stabilized mechanical seals should get 3-5 years of useful service. If they are getting less, then they could be installed on worn equipment that needs shaft support, or flush fluid characteristics need analysis.

A: Pusher type seals are used more commonly in low S.G. (<0.7) services. In a bellows seal, the secondary sealing element (bellows) generally has a larger diameter than a pusher seal, therefore the closing area is less.

A: Pusher seals utilize a dynamic secondary seal which moves axially with the major seal face. Non-pusher seals have a static secondary seal which stays stationary against the shaft or sleeve. Defined by the secondary seal type: o-ring or polymer wedge versus bellow, rubber or metal.

A: All mechanical seals are hydraulically balanced to control the opening and closing forces on the seals rings. The measure of hydraulic balance is called balance ratio. A mechanical seal with a balance ratio of one or more is an unbalanced seal, whereas a seal with a balance ratio of less than one is a balanced seal.

A: There are spring-loaded and non-spring lip seals, with non-spring lip seals being used for slower shaft processes. With mechanical seals, everyday wear and tear maintenance is reduced because the seals have inboard springs which make them self-adjusting as the faces wear down.