Bray Series 762 SlurryShield Flanged Slurry Valve

Twin rubber sleeves that shield the metal parts from the slurry

The Bray Series 762 SlurryShield is a bidirectional heavy-duty slurry valve for demanding, high-pressure slurry applications. Instead of a seat that rubs on the gate, it uses twin elastomer sleeves and a push-through gate: the gate pushes through the sleeves to close, and in the open position the energized sleeves cover every metal part so the flowing media never touches them. The two-piece bolted body is flanged, in ductile iron for NPS 3 to 28 and WCB carbon steel for the larger sizes, and the valve is full bore with an unobstructed flow path.

Bray prints the size range as NPS 3 to 48 (DN 80 to 1200) in the brochure; the product guide extends it to NPS 54. The applications named are mining (primary and secondary milling, primary and secondary cyclones, flotation cells, thickeners and filter pumps), HPAL and POX autoclave service and process pumps, power, pulp and paper, alumina, chemical and cement.

Technical specifications

Source: Bray brochure EN_V6007_S762 and datasheet EN_SDS_762. Bray notes that MSS SP-81 and MSS SP-151 do not apply to elastomer-sleeved slurry valves.

Sleeves, J-ring and protection features

The sleeve is reinforced by a fully encapsulated J-ring that supplies memory assist and guarantees bidirectional zero leakage. Sleeve retainers are standard on all sizes to keep compression uniform. Upper and lower protective stem covers are standard, which extends cycle life in dirty and dusty plants, and an optional bottom flush plate with tapped ports allows safe discharge of media and a flush-water connection.

Bray warns that continuous exposure of EPDM-HT to elevated temperature will age the elastomer prematurely, and that the valve must not be operated when the media in the line is frozen. Gate material is the lever for pressure: the same body takes a 316 gate for 100 psi duty, a 2205 duplex gate up to 232 psi in smaller sizes, or a 17-4PH gate for 290 psi.

Where the 762 fits among the slurry range

The 762 is the flanged heavy-duty choice, with a wide size range reaching 48 inches. The 768 is the wafer-body equivalent to NPS 24, the 767 is the WCB high-pressure version in a CL300 wafer body, and the 765 is a compact wafer valve for NPS 2 to 12. Operators include handwheel, bevel gear, pneumatic, hydraulic and electric actuators, and Bray lists a linear position sensor for its pneumatic knife gate actuators.

How the Bray Series 762 works

The gate is pushed through two rubber sleeves to close the line. In the open position the energized sleeves cover every metal part, so the slurry only touches the elastomer. This avoids a seat that rubs on the gate and wears in abrasive service.

Where the Series 762 is used

• Primary and secondary milling
• Cyclones and flotation cells
• Thickeners and filter pumps
• Autoclave service and process pumps
• Power, pulp and paper, alumina, chemical and cement plants

Selection checklist for the Series 762

• Valve size
• Working pressure
• Gate material
• Sleeve material
• Slurry temperature
• Body material
• Flange drilling
• Actuator type

Installation, commissioning and maintenance notes for the Series 762

Support the valve and its pipework so no pipe load acts on the body. Fit the actuator and check the full open and closed positions. Flush the line before service where the process allows. Inspect the sleeves and the gate at regular intervals.

Requesting a quotation for the Bray Series 762

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

Series 762 valve type

It is a bidirectional heavy-duty slurry valve.

Series 762 name

Bray calls it the SlurryShield.

Series 762 sleeves

It uses twin elastomer sleeves and a push-through gate.

Series 762 flow path

The valve is full bore with an unobstructed flow path.

Series 762 body

The body is two-piece, bolted and flanged.

Series 762 body material

The standard body is ductile iron for NPS 3 to 28 and WCB for larger sizes.

Series 762 size range

The brochure lists NPS 3 to 48, which is DN 80 to 1200.

Series 762 316 gate pressure

With a 316 gate the pressure is 100 psi for NPS 3 to 24.

Series 762 larger sizes

With a 316 gate it is 75 psi for NPS 26 to 42 and 50 psi for NPS 48.

Series 762 duplex gate pressure

With a 2205 duplex gate the pressure is 232 psi for NPS 3 to 18.

Series 762 high pressure gate

A 17-4PH gate gives 290 psi for NPS 3 to 20 per the datasheet.

Series 762 standard gate

The standard gate material is 316.

Series 762 gate options

Gate options include 304, 317, SAF 2507, 2205 duplex, 17-4PH, Hastelloy C, Monel and titanium.

Series 762 sleeve material

The standard sleeve is natural rubber.

Series 762 natural rubber range

Natural rubber works from minus 51 to plus 74 degrees C.

Series 762 Buna-N range

Buna-N works from minus 36 to plus 90 degrees C.

Series 762 EPDM-HT range

EPDM-HT works from minus 54 to plus 150 degrees C.

Series 762 stem

The stem is 304.

Series 762 gland plate

The gland plate is carbon steel.

Series 762 secondary seal

The secondary seal is EPDM.

Series 762 topworks

The topworks are steel.

Series 762 leakage testing

Bray tests the valve for bidirectional zero leakage across the sleeves.

Valve records for the Series 762

Record the size, the gate and sleeve materials and the date of each sleeve inspection.

Choosing the right Series 762 sleeve

Choose the sleeve material from the slurry chemistry and temperature.

Documents and quotation

The Bray brochure is attached as the datasheet; the page also lists an operation and maintenance manual, a technical manual, a datasheet and a recommended specification. Please confirm slurry density, particle size, pH, temperature, pressure, flange drilling, gate alloy and operator before ordering.

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