Masoneilan 39003 Series High Performance Butterfly Valve (HPBV)

Overview

The Masoneilan 39003 Series High Performance Butterfly Valve, usually abbreviated HPBV, is a heavy-duty automatic throttling control valve for large-line applications in which a conventional swing-through butterfly valve would wear out or leak. It differs from the conventional design in two ways that Baker Hughes treats as fundamental: a PTFE, RTFE or metal seal ring takes the place of a liner, and the disc operates with double offset, meaning the shaft is offset from the valve centerline and the seal is offset from the shaft. Together these features give the Masoneilan 39003 a longer seal life, lower torque and a more predictable flow characteristic than a lined butterfly valve.

As the official trusted supplier for Masoneilan, Seven Star LLC supplies the Masoneilan 39003 to water, power, oil and gas and process customers throughout the Sultanate of Oman and the GCC. Large-diameter cooling water, seawater and hydrocarbon lines are where butterfly valves earn their place, and our instrumentation division in Muscat helps engineers choose the seal, body material and actuator before a request for quotation is raised.

Double Offset Operating Principle

In the Masoneilan 39003 the seal ring centerline is offset from the shaft centerline, and the shaft centerline is offset from the valve centerline. This eccentric geometry makes the disc cam away from the seal almost immediately as it begins to rotate, so contact between the disc and the seal is lost after only a few degrees of travel. Sliding friction, which is the main cause of seal wear in interference-fit butterfly valves, is therefore confined to the first part of the stroke, and the valve needs less breakaway and seating torque from its actuator.

The same offset gives a useful flow characteristic. Baker Hughes describes an approximately equal percentage characteristic over the full 90 degree rotation, with a Cv ratio of 100:1, and bidirectional flow. The seal itself is a dynamic, pressure-assisted member, so rising line pressure presses it harder against the disc edge. This is why the Masoneilan 39003 can offer ASME Class VI shut-off throughout the Class 150, 300 and 600 ratings in soft-sealed constructions, and why the disc tends to move in the direction of flow and help the actuator at higher operating pressures.

Engineering Design of the Masoneilan 39003

The Masoneilan 39003 body is a wafer or lug design with an integral bonnet, made in carbon steel (ASTM A216 grade WCB or A105) or stainless steel (ASTM A351 CF8M or A182 F316). The disc is stainless steel, nitrided, with a 360 degree uninterrupted spherical edge. The shaft is solid, blow-out proof 17-4 PH stainless steel with a keyed outboard end, supported by PTFE-lined fibreglass bearings, bronze bearings up to 750 degrees Fahrenheit and nitrided stainless steel above that. Tapered pins attach the disc to the shaft, so shaft and disc can be replaced separately in the field instead of as a matched set.

Three seal designs are offered on the Masoneilan 39003. The soft seal gives bidirectional bubble-tight shut-off with a patented self-energizing shape, even at vacuum and low pressure. The metal seal pairs an Inconel seal and a 300 series stainless steel backup ring with a case-hardened disc for use up to 900 degrees Fahrenheit, with Class IV leakage. The fire-safe seal places a hydroformed Inconel metal seal behind the soft seal so that shut-off is maintained if the soft seal is lost in a fire, and it adds stainless steel outer bearings and fireproof packing. Larger sizes use a two-piece shaft with an end seal or lower packing seal.

Key Features

The following features, from the Baker Hughes technical specification, explain why the Masoneilan 39003 is specified for high-capacity throttling duties:

• Double offset (eccentric) operation separates the disc from the seal after a few degrees of rotation, which extends seal life and lowers operating torque.
• Bidirectional, pressure-assisted sealing provides ASME Class VI leakage with PTFE or RTFE seals and Class IV leakage with metal seals.
• An approximately equal percentage characteristic and a Cv ratio of 100:1 give good control over a wide range of flow.
• Extra-heavy keyed shafts with triple bearing support avoid lost motion and backlash and resist deflection from side loading.
• Field-replaceable shaft and disc, joined by tapered pins, mean the two parts need not be bought as a set.
• The soft seal replacement procedure for the Masoneilan 39003 needs no special tools, which shortens turnaround during planned maintenance.
• Fire-safe, soft seal and metal seal designs allow one body series to cover utility, hydrocarbon and high-temperature service.
• Wafer, lug and single-flanged connections fit ASME Class 150, 300 and 600 pipe flanges, in sizes from 2 to 48 inch.

Industrial Applications

The Masoneilan 39003 suits high-capacity throttling applications where a compact wafer or lug body and a high Cv are an advantage. In Oman the Masoneilan 39003 matches cooling-water circuits at power and desalination plants, seawater intake and return headers, fire-water and utility distribution, and large hydrocarbon and process lines in refineries and gas plants. The fire-safe seal option is particularly relevant on hydrocarbon lines, while the PTFE and RTFE seal options suit clean utility service in the Sohar and Salalah industrial zones. Steam service is limited: PTFE-sealed valves are rated for 50 psi saturated steam and RTFE valves with an AFLAS O-ring for 100 psi.

In Oman and the GCC, Seven Star LLC supplies the Masoneilan 39003 alongside the rest of the butterfly range and its actuation. Engineers comparing options can review the Masoneilan 39004 high-performance butterfly control valve and the Masoneilan 39005 high performance butterfly valve, and for positioning can add the Masoneilan SVI3 digital valve positioner.

Technical Specifications

The table below summarises the published data for the Masoneilan 39003 from the Baker Hughes technical specification (Rev. B, 07/2020). Please refer to the full document for the Cv and FL tables, allowable pressure drops, weights and dimensions.

Related Masoneilan rotary valves include the Masoneilan 33000 Series triple offset butterfly valve and Masoneilan 31000 Series rotary control valve.

Request a Quote for Masoneilan 39003

Seven Star LLC invites engineers, EPC contractors and maintenance planners across Oman and the GCC to submit a formal request for quotation for the Masoneilan 39003. Please send the line size, pressure class, fluid and temperature, required shut-off class, seal type (soft, metal or fire-safe) and the preferred actuator, and our team will confirm the configuration, advise on regional availability and provide the Baker Hughes technical specification for download from this page. In Oman and the GCC, Seven Star LLC delivers genuine products with manufacturer documentation and responsive local support.