Bray Series 30/31 Resilient-Seated Butterfly Valve

Overview

Bray Series 30/31 resilient-seated butterfly valves are among the most widely specified flow-control products from Bray International, engineered for reliable on/off and throttling service across water, HVAC, and general industrial piping systems from NPS 2 to 20 (DN 50 to 500). The Series 30/31 combines a compact wafer or lug body with a broad selection of disc and seat materials, allowing a single valve platform to be configured for potable water, chemical, or general process duty from a single product family.

With fast quotation turnaround and technical support, Seven Star LLC supplies the Series 30/31 valve family — along with Bray’s matched actuation and controls range — to industrial and utility projects across Oman and the Sultanate, with manufacturer documentation and local technical support, giving procurement teams a single accountable Bray Series 30/31 source for documentation and long-term spares.

Operating Principle

The Bray Series 30/31 valve controls flow through a quarter-turn rotating disc centered on a through-shaft within a molded elastomer seat. In the closed position, the disc compresses against the O-ring-style molded seat around its full circumference, creating a bubble-tight seal without a separate machined metal seating surface; rotating the shaft ninety degrees swings the disc parallel to the flow path, opening the bore with minimal flow restriction. This design allows the valve to serve equally well in tight-shutoff isolation service and in modulating throttling applications where the disc is positioned at intermediate angles to regulate flow rate.

Because the molded seat also functions as the flange gasket against the adjoining pipe faces, the Series 30/31 eliminates the need for separate gasket material at each flange connection, and its symmetrical wafer or lug body accommodates minor pipe misalignment while still achieving reliable sealing. The practical consequence for plant engineers is faster installation, fewer spare parts to stock, and dependable shutoff performance across repeated cycling in both isolation and throttling duty.

Engineering Design of the Bray Series 30/31

Physically, the Bray Series 30/31 is available in cast iron, ductile iron, carbon steel, or aluminum body construction, with disc material options spanning nylon 11-coated ductile iron, aluminum bronze, stainless steel, Hastelloy®, and Halar®-coated ductile iron to match specific corrosion and erosion requirements. The molded elastomer seat is offered in BUNA-N, EPDM, FKM, or polyurethane compounds, giving specifying engineers wide latitude to match seat chemistry to the service fluid and operating temperature, which spans −20°F to 400°F (−29°C to 204°C) across the family.

The valve’s flange drilling conforms to ASME B16.1 Class 125, ASME B16.5 Class 150, and EN 1092 PN 10/16 patterns, allowing the same valve body to bolt into piping systems built to either American or European flange standards without adapter spools. Bray’s vertically integrated design philosophy extends the top-works to a common actuation interface, so the Series 30/31 accepts Bray’s own pneumatic and electric actuators as a factory-matched valve-and-actuator package engineered and tested together rather than paired after the fact.

Key Features

The Bray Series 30/31 resilient-seated butterfly valve combines broad material flexibility with proven sealing performance:

• Size range from NPS 2 to 20 (DN 50 to 500) covers the majority of general industrial and utility piping applications.
• Body material options in cast iron, ductile iron, carbon steel, and aluminum suit differing service and budget requirements.
• Disc materials including stainless steel, aluminum bronze, and Hastelloy® provide corrosion resistance for aggressive media.
• Molded BUNA-N, EPDM, FKM, or polyurethane seat compounds double as the flange gasket, simplifying installation.
• Dual ASME and EN flange-drilling compatibility allows use across both American and European piping standards.
• Operating temperature range of −20°F to 400°F (−29°C to 204°C) suits a wide span of process conditions.
• Factory-matched compatibility with Bray’s own pneumatic and electric actuators for fully engineered automated packages.
• Approvals including ABS, ATEX, DNV, FDA 21 CFR 177.1550, and NSF 61/372 support both marine and potable water applications.

Industrial Applications

Water and wastewater treatment facilities across Muscat and the wider Sultanate specify the Bray Series 30/31 for isolation and flow-balancing duty in treatment plant piping and pump stations, where its NSF 61/372-listed seat options meet potable water compliance requirements. Commercial and hospitality HVAC systems throughout Oman similarly rely on the Series 30/31 for chilled-water and condenser-water isolation valves, benefiting from the valve’s compact footprint in mechanical rooms with limited space.

With engineering support in Muscat, Seven Star LLC supplies the Series 30/31 to process industries throughout the Sohar and Salalah economic zones and the broader GCC, supporting oil and gas facilities, power generation plants, and desalination projects that require dependable throttling and isolation valves at scale, often paired with Bray’s own automated actuator packages for remote operation. Lead time confirmed at quotation and technical support with selection help these projects plan commissioning schedules for the Bray Series 30/31 and its factory-matched actuation packages.

Technical Specifications

The table below summarizes the core specifications of the Bray Series 30/31 resilient-seated butterfly valve:

Request a Quote for Bray Series 30/31 Resilient-Seated Butterfly Valve

Seven Star LLC is ready to support your project with formal RFQ processing, material and pressure-class selection assistance for the Bray Series 30/31, and the complete technical datasheet on request. With manufacturer documentation available on request, Seven Star LLC supplies the range with technical support with selection, so contact our valve division today to specify the right Series 30/31 configuration for your project and receive a competitive quotation.

Browse the full Bray International range or see more Control Valves products supplied by Seven Star LLC in Oman and the GCC.

See also: Bray Series 20/21 Resilient Seated Butterfly Valve.