Mechanical seals manufacturer and supplier John Crane has four contracts with key oil refine- ries in South Africa to deliver rotating equipment to increase pump reliability and reduce the cost of ownership for the end-user.

The company supplied the John Crane Dart One wireless remote monitoring system – the latest in advanced rotating equipment condition monitoring – to the oil refineries this year and notes that it has reduced its mean time between failures from 68 to 48 months in less than two years on all its reliability projects.

“It allows machinery in difficult envi- ronments to be monitored remotely, safely and reliably, while also providing refineries with the necessary information to make decisions about plant and machinery conditions,” says John Crane MD Aziz Sallie.

He notes that the Dart One system, which has received certification from Atex Zone 1, is equipped with a sensor that transmits information wirelessly to any international location, making it virtually maintenance free.

“The John Crane Type 2874NE metal bellows dual gas seal is designed for high-temperature applications. This gas-lubricated nonelastomer seal meets API 682 design requirements and features noncontacting operation, as well as John Crane’s internally pressurised, outward pumping spiral groove face technology,” explains Sallie.

He adds that, together with features such as Inconel-welded metal bellows and nonelastomeric carbon graphite secondary seals, this makes the John Crane Type 2874NE a good choice for sealing high-temperature process fluids up to 425 ºC on rotating equipment.

Sallie points out that the company recently launched a sealing solution that provides wet-running and dry-running service capabilities from one common seal platform.

“The Type 3740 cartridge split seal is our most advanced split seal product, allowing more difficult conditions to be sealed. The wet-running seal is quick and easy to install, and provides reliable performance in pump and rotating equipment fluid services.

“The Type 3740 dry-running split seal is designed for the large shaft run-out and harsh operating conditions commonly found on top-entry vessel-mixing services and other dry-running applications,” he states.

The company offers next-day delivery to oil refineries for mechanical cartridge seals, enabling them to keep their plants and processes running at all times, notes Sallie, adding that this is supported by R200-million in stock that John Crane keeps at its service centres specifically for refineries.

John Crane is fully capable of managing pump and seal upgrade projects, from design to commissioning.

“We provide support for the pump original-equipment manufacturer on seal and coupling selection. We also provide technology upgrades on gas seal support systems, including turnkey projects and centrifugal pump and seal upgrades, to meet environmental emissions regulations,” he says.

John Crane recently aligned its projects and engineering team to provide projects and end-users with project flexibility and the technical competence they require.

“The company’s current planned projects are still in the feasibility stage. We are one of the only suppliers that produce Plan 53B systems locally, along with all the required certification and documentation,” notes Sallie.

John Crane provides full training at its contracted-for centrifugal pump operation, failure analysis seal selection and operation, seal support systems and pump assembly for reliability improvement, as well as on-site root cause and failure analysis.