Split Pump Seal

WHEN TO USE A SPLIT SEAL

Replacing a mechanical pump seal (component or cartridge) typically requires the disassembly of the pump. One way to avoid this cumbersome process is to use a split seal. Since the seal faces and other components are literally divided in half, they can be installed without pump disassembly. Split seals are typically used on mixers, large-volume and shafted pumps, and agitators.

COMMON SPLIT PUMP SEAL APPLICATIONS

Water

Sewage

Oil

And many others

BENEFITS OF USING SPLIT SEALS

  • Less leakage than using traditional packing
  • No wear on the shaft sleeve
  • Maintenance free during operation
  • Most Importantly, it saves time and money

Some types of pump machinery are challenging to maintain. For example, heavy components and large pump shafts are challenging for pump operators. When repairs are needed in these types of equipment, using a split seal means no need to remove the pump’s motor with a crane, saving time and expense. For this reason, despite the expert skill required to install split seals, being able to replace them without removing the pump’s motor is a huge advantage, even though split seals are more expensive than traditional cartridge seals.

SPLIT MECHANICAL SEAL DESIGN

A split mechanical seal is designed to be installed without disassembling the equipment. It consists of two segments, a stationary segment and a rotating segment, that are pre-assembled before installation. The stationary segment is typically installed on the equipment casing, while the rotating segment is installed on the equipment shaft.

When the equipment is in operation, the two segments come together to form a seal that prevents fluid leakage. The split design allows for easy installation and maintenance, making it an ideal choice for equipment that cannot be easily dismantled or where space is limited.

Highlights of Split Pump Seal Design

  • Fully split into two segments and comes pre assembled

  • Balanced and is externally pressurized

  • Has a flush connection

  • Easy to remove assembly clips enable self-centering during split pump seal installation

  • No need for set screws

SPLIT SEAL REPLACEMENT

Split seal replacements are commonly the most complex mechanical seals. For that reason, they are not always used over the existing OEM seals. Often, the replacement of these split seals is determined by the type of seal already used in the pump. The common problem is that the original seal being used may not be the best choice based on the fluid in the pumping process.

The fluid is often the last thing considered during the pump design process, yet it can have the most significant operational impact on the pump seals. When the pumped fluid contains anything other than water, seal problems can arise. Most split seals don’t leak because they wear out. The most common reasons for seal failure are running dry, erosive fluids, excessive vibration, fluid contamination, and mechanical failures of pump shafts and bearings.

If your mechanical seal fails or needs to be replaced, here are five critical factors you will want to consider for the proper installation of split pump seals: 

  1. Cleanliness
  2. Correct set length (especially on pumps with locking collars)
  3. Material selection
  4. No hyperextension of the bellows (the elastomeric flexible component of the seal head)
  5. Mounting the seal head with proper alignment

RUN TEST SPLIT SEALS

The complex design of a split seal and the necessary steps to assemble it add to the challenge of adequately installing these seals. In most pump processes, you can’t actually see the seal. Therefore, the only way you will truly know a seal is installed correctly is with run time. If best practices are followed during installation, it is difficult to determine if the seals are correctly installed until the pump is turned on.

PLATINUM PERFORMANCE PRODUCTS FOR SPLIT SEALS

Contact Platinum Performance Products for your split seal replacement. For additional information and assistance for all your pump and seal applications, contact us at team@3ppumps.com.