bellows mechanical seal in stock

A Bellows seal does not have a secondary seal that must move along the shaft or sleeve to maintain seal face contact. The secondary seal is static state at all times, even when the pump is in operation.

Primary seal face wear is typically accommodated by welded metal or elastomeric bellows which move to assist in the compression of the rotary to stationary seal faces.

Bellows seals allow for high and low temperature applications when used in conjunction with metal bellows. They do not require a rotating secondary seal, which means it is not prone to secondary seal hang-up or fretting along the shaft or sleeve.

John Crane brings you the world’s most complete selection of performance-proven edge-welded and formed metal bellows sealing products used in a wide range of rotating equipment such as pumps, compressors, mixers, and agitators. Our experience in diverse industries such as oil & gas, petrochemical, chemical, refrigeration compressor, pharmaceutical, food processing, pulp & paper, and more have proven the soundness of John Crane’s metal bellows design.

In many cases, Cartridge Seals may contain the exact same major items that are sold separately as Component Seals. These pieces include the Rotary Seal and Stationary Face as well as other minor parts like O-rings or Gaskets all required at assembly. The advantage of using a Cartridge Seal is that the time required for installation, and even more importantly, the possibility of error during installation is dramatically reduced. When installing a Cartridge Seal, the necessity of having to measure internal components positioning on the shaft to achieve proper face loading is eliminated. Cartridge Seals come pre-assembled from the factory with all internal components assembled with proper face loading and all pieces in place, exactly where they should be. Cartridge Seals eliminate the need to handle delicate, polished parts such as Seal Faces that can be compromised by the presence of dirt, smudges and oils that can result from handling during assembly. So, for the easiest and most reliable Seal installation, Cartridge Seals go a long way towards helping you achieve trouble free startup and extended service life from your equipment.

Yes, Flexaseal’s edge-welded bellows are completely manufactured at our Vermont factory. Our welding department and engineering staff work closely together to control the manufacturing quality of all bellows assemblies, from stamping sheets of foil stock through welding cores and end fittings, evaluating spring rates, and pressure testing the completed assembly. We use the TIG (Tungsten Inert Gas) welding process which provides the finest control of the weld arc, resulting in efficient, clean, and long-lasting welds.

Formed bellows are manufactured from either welded (seamed) or seamless tubing and utilize extensive automation for mass production. This process offers some cost benefits over edge-welded bellows assemblies however, formed bellows are limited to materials which can be elongated through either rolling or hydroforming. Formed bellows typically have thicker convolution structure with higher spring rates and larger deviations than edge-welded bellows which impacts precision loading.

Flexaseal designs and manufactures edge-welded bellows. Our bellows production begins by stamping male and female diaphragms from sheet (foil) stock. We inventory foil stock including various Hastelloy™ and Inconel® grades, titanium and Monel® as well as cryogenic-grade materials, to accommodate a wide range of applications. Diaphragms are TIG-welded together to create a convolution, and these convolutions are assembled together and welded to create the bellows core. Bellows core sizes can range from just a few welded convolutions to 100+ convolutions for a hermetic bellows assembly.

Contrary to popular belief, it is possible to repair a rotary bellows assembly. If pressure testing reveals leakage around the seal face, Flexaseal will de-insert the current face and check the retainer for any damage. If the retainer is within the necessary tolerances, FAS will insert a new face into the assembly as well as replace the other wear parts (O-ring and hardware).

If the bellows rotary shows visible damage to either the bellows core or end fittings, or a pressure test reveals leaks in the assembly itself, Flexaseal recommends a new bellows assembly to ensure sealing integrity.

In a pusher seal design, the secondary sealing component – usually an O-ring or a wedge — must move axially to compensate for wear, vibrations, and movements of the shaft.

Welded bellows assemblies also offer the benefit of an inherently balanced seal design. Mechanical seal balance refers to the ratio of the opening and closing areas of the seal faces. Both a balanced and unbalanced design may have the same opening face area but the balanced seal’s closing area is smaller, reducing the load on the faces. This reduced load means less heat generated at the seal faces, enabling the balanced seal to run cooler than an unbalanced seal design. This cooler operating environment positively impacts a seal’s run time.

If your facility must comply with API Standard 682 which requires all Type B or C cartridge seals to utilize a balanced seal design, standardizing on hydraulically balanced, welded metal bellows seals ensures satisfactory seal run time and low seal maintenance for your equipment.

Operating length (OL) - also referred to as installed or working length: The axial length of a bellows assembly as installed to the designed compression. The term may also refer to the dimensional range within which a bellows assembly can safely be operated.

Mechanical seals, whether a pusher or bellows design, need a specific amount of compression to ensure the faces are in contact to maintain the correct amount of lubrication to operate (dry-running seal designs are the exception to this statement.) Both the Free Length and Operating Length are necessary for this compression calculation: Free Length – Operating Length = amount of compression. Here’s an example:

RT6SB Elastomer Bellows Mechanical Seal Type RT6SB is the stationary mechanical seals, good perfromance in the [...]RTEA100 EagleBurgmann Type EA100 Replacement Common mechanical seals Type RTEA100 is designed for the low duty [...]RT16 Pac-Seal Type 16 Replacement Type RT16 series is whole structure of elastomer bellows mechanical seals, [...]RT6 John Crane Type6 Replacement Compact, elastomer bellows mechanical seals Type E widely used in small [...]RTBT-PN EagleBurgmann Type BT-PN Replacement RTBT-PN mechanical seals with special spring arrangement allows short axial installation [...]RT2100 John Crane Type2100 Replacement Compact,single-spring,elastomer bellows mechanical seals Type 2100 provides maximum performance and efficiency. [...]RT2 John Crane Type2 Replacement Non-pusher elastomer bellows mechanical seal type 2 is ideal for use [...]RT1 John Crane Type1 Replacement Elastomer Bellows mechanical seal RT1 is suitable for a wide range [...]RT21 John Crane Type21 Replacement Mechanical seal in the RT21 series is the ideal for general-purpose [...]RTMG1 EagleBurgmann Type MG1 Replacement RTMG1 series is the most common rubber bellows mechanical seals allow [...]RT502 John Crane Type502 Replacement Mechanical Seal Type RT502 is one of the best performing bellows [...]

Zigong Ke Yu Seal Science and Technology Co.,LTD located in hightech industry of zigong city in sichuan province. We are large manufacturer and exporter of high pressure,high temperature, high speed mechanical seal. Our products widely used in KSB pumps, Grundfos pumps, Flowserve pumps, etc. And our mechanical seal can exactly replace original mechanical seal in sharpe agitator, ekato agitator, lightnin agitator, sardik agitator, mut agitator, mixpro agitator etc. We design and manufacture mechanical seal up to 60 bar, 3000rpm, 300C°in different material of constructions like ss316/316L,ss304, Sillicon Carbide, Tungsten Carbide, Carbon, Viton, NBR, EPDM ,PTFE, etc. From pumps to reactor for various application. We can also provide ODM and OEM precision machined parts according to your drawings or design requirements. For exmple,customized shaft, shaft sleeve, as well as a variety of high-precision, high request products. Materials that can be produced include stainless steel, titanium and any other metal material of different grade.