Key Features

• DIN Standard Compliance: Fully compliant with DIN 24960 (EN 12756) standards, ensuring a perfect fit for European chemical and industrial pumps.

• Versatile Configuration: Available in Unbalanced (58U/59U) for lower pressures and Balanced (58B/59B) for higher pressure applications.

• PTFE Wedge or O-Ring: Designed with a versatile secondary seal area that can accommodate PTFE wedges (Type 59) for chemical resistance or O-rings (Type 58) for general duties.

• Multi-Spring Design: Uses multiple small springs located outside the fluid path (in some configurations) or protected to provide uniform face loading without clogging.

• Shaft Protection: The seal design does not fret the shaft, as the dynamic secondary seal moves against a hardened sleeve or the seal's own components depending on the specific sub-model.

Product Specifications

Workshop

This workshop is equipped with professional processing equipment and integrated with standardized material warehousing management, enabling a one-stop production process from precision machining to finished product delivery. It ensures part machining accuracy and production efficiency, meeting various high-specification manufacturing requirements.

Product Research, Development and Testing

Our Product R&D and Testing focuses on optimizing seal performance through advanced simulation and material analysis. All seals undergo rigorous trials, including thermal cycling and pressure tests, to ensure durability, minimal leakage, and long service life in demanding industrial environments.

Industry Solutions

FAQs about John Crane 58B 58U 59B 59U Mechanical Seal

Q: What is the difference between B and U?

A: "U" stands for Unbalanced, suitable for lower pressures. "B" stands for Balanced, which has a stepped face geometry to handle higher pressures and reduce heat generation.

Q: What is the difference between Type 58 and Type 59?

A: Type 58 vs. 59: Type 58 uses an elastomer O-ring (NBR, Viton) as the secondary seal, ideal for general-purpose fluids. Type 59 uses a PTFE wedge, designed for aggressive chemicals, high temperatures, or where elastomer compatibility is an issue.

Q: Is this seal a direct replacement for my existing John Crane 58U/59B seal?

A: Yes, this replacement is manufactured to the exact dimensional specifications of the original John Crane 58/59 series. It is a direct form-fit-function replacement for standard metric shaft sizes (14mm to 100mm) and fits the same gland plate and sleeve assemblies without modification.