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Avoiding drips on the ground

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Hydrocarbon Engineering,

The strength of mechanical seals and shut-off devices on mixers is integral to their environmental performance. Plenty mixers offer secure, reliable seals in configurations that are easy to maintain and enable seal and bearing replacement under full tank conditions.

Plenty mixers utilise a wear resistant tank shut-off device with safety check valve that provides assured tank closure for seal and bearing maintenance under full tank conditions. Welds or shrinking collars add weak spots that, from experience and testing, can increase the risk of shaft failure. The Plenty shut-off device is machined into the shaft using a single piece of metal with wear and corrosion resistant tapered metal to metal faces that are positively clamped by a bolted flange. In this way, the mixer shaft strength is not compromised and a robust seal is provided that offers reliability in even the most arduous oil and gas applications. A safety check valve is also incorporated to ensure complete shut-off before any wear parts can be removed.

Elastomer ‘O’ rings or gaskets can deform, wear or perish over time. Failure of these parts may not be realised until the operator cannot make a positive shut off. This would then require the mixing tank to be drained to below the shaft center line, increasing time and cost of maintenance. The design of Plenty mixers does not use flexible ‘O’ Rings, expanding bellows or gaskets in the shut-off design to avoid these issues and to provide solutions that keep operators safe and the plant secure. The Plenty Shut-off device is field proven in over 1000 installations worldwide.

Plenty mixers are available with a choice of seal options to deliver the level of protection required for an application. These include single, tandem and, for maximum assurance against any leaks, double mechanical seals. Units can also be fitted with a leakage detection system. These range from simple, economical designs incorporating a drip collection reservoir and alarm that can be indicated via a local beacon or relayed to a control panel; to full API leak detection in accordance with plan 65 and plan 75.

Available as belt or gear driven units, Plenty fixed or swivel angle mixers are ideal for a full range of duties include blending, oil storage, bitumen, thermal homogeneity, and crude oil bottom sludge and water (BS&W) control. The choice of seals and leakage detection systems makes them a versatile solution.

Customers also have the added peace of mind to be able to upgrade standard seal options and add leakage detection systems at a future date if application or legislation requirements change.

Plenty mixers are proven to offer high performance, efficiency, reliability and safety in oil and gas applications. As well as a wide variety of sizes and standard options, SPX FLOW also offers expert engineering capability to design and deliver customised units or complete mixing packages to meet specific customer requirements. A long history of serving the oil, gas and petrochemical industries means solutions are designed with a clear understanding of legislative requirements and application needs to ensure the best options for process and budget.

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