TPi October 2009

f i t t ings feature on . . .

JOHN Crane, a provider of engineered products and services for the major process industries, including oil and gas, power, chemical, pharmaceutical, and other general industries, has launched a next-day delivery service within the UK for its standard range of mechanical cartridge seals. The new service covers standard size seals constructed from standard materials. “This new service reflects the fact that we understand our customers’ need to access the products they require both quickly and easily,” explained John Crane UK general manager, Colin Ure. “Any seals covered by our new service that are ordered before 2.30pm will be delivered to the customer the following working day, helping them minimise downtime and keep their processes operating at maximum efficiency.” Among the seals covered by the new service are John Crane’s 4600 Series of single and double O-ring cartridge seals, which are suitable for water and wastewater, pulp and paper and Rapid delivery of seals

harmful resonances to subcritical ranges, ensuring fail-safe operation of the compressor system. With only minimum impact on the system, the couplings even equalise misalignments caused by installation and operation. The principle of a modular design coupling system is based on one or more highly flexible Centax rubber elements made of natural rubber or silicone supplied in different ranges of shore-hardness. Combined with a membrane coupling, a link or a bolt coupling, and a wide array of flanges and hubs, the couplings achieve flexibility in all directions, and provide adaptability with regard to design and construction, with a manageable torsional stiffness. The torques cover a range from 2.5 to 650 kNm. Type-approved by renowned classifica- tion societies, the couplings are designed in consultation with the customer to meet API standards. are also available using this new service. Suitable for chemical, petrochemical and pharmaceutical applications, the modular construction of the 5610 single O-ring seal and 5620 dual O-ring seal ensures components are easily interchangeable between different models. This allows one seal family to be used throughout a plant, reducing downtime, maintenance requirements and stockholding costs. The new system can also be used to access John Crane’s FFET range of cartridge seals. Designed to reduce installation time and errors, these compact seals will fit all ANSI and DIN stuffing boxes, and offer a practical upgrade from packings. Their robust construction makes them suitable for applications involving chemicals, oil, water and abrasive liquids, especially those involving top- entry mixers where the liquid product may not provide continuous cooling and lubrication of the seal faces. John Crane – UK enquiries@johncrane.co.uk www.johncrane.co.uk

power generation applications. The compact and easy-to-install 4610 single seal is suitable for a variety of general duty applications, and the 4620 dual cartridge model meets key industry pump standards. John Crane mechanical cartridge seals S S are now available with a next-day delivery service within the UK

Standard seals in the company’s 5600 Series Universal Cartridge Seal Family

Torsionally soft alternative to all- metal couplings that limits vibration

LARGE compressor units, such as those used by companies in the oil and gas industry, are normally driven by powerful electric engines, which are connected to the compressor units by means of all-metal couplings. The drawback of this design is that harmful vibrations induced by the piston compressor, caused by high torsional stiffness and weak damping characteristics of

the couplings, are transmitted to the drive unit. This results in damage to the coupling and high loads for the bearing units, which may even cause a breakdown of the complete system. The Centax-SEC flexible coupling system from Centa offers a torsionally soft alternative to standard all-metal couplings. The flexible couplings shift

Centa – Germany info@centa.de www.centa.info

The Centax-SEC flexible coupling system offers an alternative to all-metal couplings S S

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Tube Products International October 2009

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