Bray Series 767 High-Pressure Slurry Valve, NPS 3 to 36

Up to 740 psi in a cast WCB wafer slurry valve

The Bray Series 767 SlurryShield is a bidirectional high-pressure slurry valve with a cast WCB two-piece bolted wafer body. It keeps the sleeve-and-push-through-gate principle of the SlurryShield family, in which J-ring steel-reinforced elastomer sleeves close around the gate, retaining rings are standard through the whole size range, and the energized sleeves shield the metal parts when open. What sets it apart is the pressure ladder: 300 psi (20 bar), 450 psi (30 bar) and 740 psi (51 bar), depending on gate material and size.

The brochure size range is NPS 3 to 36 (DN 80 to 900), drilled to ASME B16.5 Class 300 as standard. Bray lists mining, pulp and paper, general industry, power, chemical and cement as application sectors.

Technical specifications

Source: Bray brochure EN_V-6011_S767 and datasheet EN_SDS_767. The brochure pressure table groups ratings by gate material; confirm the rating for the specific size with Bray.

Flush, drain and installation features

A bottom flush plate with tapped ports, or a drain bucket, is available for safe discharge of media and easy flush-water connection; the drain bucket is included with all 51 bar valves. A protective stem cover is standard, and ample clearance for push-through allows complete gate closure.

As with the other sleeved slurry valves, Bray states that MSS SP-81 and MSS SP-151 do not apply, that each valve is tested for bidirectional zero leakage across the sleeves, and that the valve must not be operated if the media in the line is frozen. EPDM sleeves age prematurely if continuously exposed to elevated temperature.

Choosing the 767 over the other SlurryShield valves

Select the 767 when pressure rather than size is the constraint, for example autoclave feed, high-head pump discharge, thickener underflow or filter-press feed. The 762 and 768 serve lower-pressure duty at 150 psi drilling, and the 765 is the compact 90 psi option. Operators include handwheel, bevel gear, pneumatic, hydraulic and electric actuators; Bray also lists a linear position sensor for its pneumatic knife gate actuators.

How the Bray Series 767 works

The Series 767 is a slurry valve with a push-through gate. When the valve is open, the gate sits clear of the flow and the bore is open. When it closes, the gate is pushed through the line and two steel-reinforced rubber sleeves close around it. The sleeves seal on both sides, so the valve works in both flow directions. The sleeves also cover the metal parts when open, so abrasive slurry meets rubber and not the gate or body. The body is cast WCB, in two bolted halves, and fits between flanges.

Where the Bray Series 767 is used

• Mining slurry lines
• Pulp and paper
• Power plant ash and slurry
• Chemical processing
• Cement plants

Selection checklist for the Bray Series 767

• Size from NPS 3 to 36
• Pressure of 300, 450 or 740 psi
• Gate material: 316, 2205 duplex or 17-4PH
• Sleeve material: natural rubber or EPDM
• Temperature of the slurry
• Body option for corrosion
• Flush plate or drain bucket
• Actuator and topworks

Installation, commissioning and maintenance notes for the Series 767

Mount the valve between ASME B16.5 Class 300 flanges with enough clearance for the gate to push through. Fit the stem cover and connect the flush or drain ports if they are used. Cycle the valve before the line is put into service. Inspect the sleeves for wear on a regular schedule, and flush the valve after shutdown to stop solids from setting.

Requesting a quotation for the Bray Series 767

Please send the size, the pressure, the slurry, its temperature, the sleeve and gate materials and the actuator. Seven Star LLC serves industrial customers in Oman and the GCC and replies with a quotation based on the information provided.

Series 767 pressure ratings

A 316 gate is rated 300 psi for NPS 3 to 10. A 2205 duplex gate is rated 450 psi for NPS 10 to 36 and 740 psi for NPS 3 to 8. A 17-4PH gate is rated 740 psi for NPS 3 to 36.

Series 767 sleeve temperature

Natural rubber runs from minus 51 to 74 degrees C. EPDM runs from minus 54 to 120 degrees C.

Series 767 body and gate options

Body options are CF8M, CF3M, SAF 2205 and SAF 2507. Gate options include 304, 317, Hastelloy C and Monel.

Series 767 certification

The brochure lists Canadian CRN and PED Category I Module A for Group 2 liquids.

Valve records for the Series 767

Keep the serial number, the sleeve change dates and the flush schedule in the valve file.

Choosing the right Series 767 configuration

Choose the gate from the pressure rating and the sleeve from the slurry and temperature.

Documents and quotation

The brochure is attached as the datasheet, and the Bray page also lists an operation and maintenance manual, datasheet and recommended specification. Before ordering, state slurry properties, working and test pressure, temperature, flange drilling, gate alloy and operator.

See the wider range of control and isolation valves on our catalogue, or send the model name and order number for a quotation.