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Watts Double Check Valve Assembly: 757, 3 in Pipe Size, Flange x Flange, 31.75 in Overall Lg - Watts Double Check Backflow Preventers
WattsWatts Double Check Backflow Preventers

Watts Double Check Valve Assembly: 757, 3 in Pipe Size, Flange x Flange, 31.75 in Overall Lg

The Watts 757 Double Check Valve Assembly is a 3-inch backflow preventer with flange x flange connections and an OSY gate valve shut-off. This assembly, identified by MPN 3 757 OSY, measures 31.75 inches in overall…

SKU 3G-OTH-434583

Also listed as: 3757OSY · 3-757-OSY

Brand
Watts
Item
Double Check Valve Assembly: 757, 3 in Pipe Size, Flange x Flange, 31.75 in Overall Lg
Category
Watts Double Check Backflow Preventers
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Worldwide DHL shipping from Singapore; 7–14 business days door-to-door for most destinations.
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Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.

Technical Specifications

Watts
Manufacturer Part Number
3 757 OSY
Type
Flange x Flange, PPO
Overall Lg
31.75 in
Pipe Size
3 in
Connection Type
Flange x Flange
Shut-Off Valve Type
OSY Gate Valve

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Watts Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The Watts 757 Double Check Valve Assembly is a 3-inch backflow preventer with flange x flange connections and an OSY gate valve shut-off. This assembly, identified by MPN 3 757 OSY, measures 31.75 inches in overall length and is constructed from PPO.

Frequently Asked Questions

What is a Watts 757 double check valve assembly used for?

The Watts 757 double check valve assembly prevents backflow of non-potable water into potable water supplies in commercial and industrial plumbing systems. It is commonly installed on fire sprinkler lines, irrigation systems, and boiler feed lines to protect against cross-connection contamination.

What are the specifications of the Watts 757 3 inch double check valve?

The Watts 757 double check valve assembly has a 3-inch pipe size with flange x flange connections and an OSY gate valve shut-off. Overall length is 31.75 inches, body material is PPO, and the manufacturer part number is 3 757 OSY. It is designed for backflow prevention in water lines.

Where to buy a Watts 757 double check valve assembly worldwide?

3G Electric supplies the Watts 757 double check valve assembly worldwide. As a global industrial sourcing partner, we handle logistics, customs clearance, and delivery to your site. Contact us for a quote on the 3-inch flange x flange model with OSY gate valve (MPN 3 757 OSY).

How to install a Watts 757 double check valve assembly?

Install the Watts 757 double check valve assembly in a horizontal or vertical orientation with flow arrow pointing downstream. Ensure flange gaskets are properly seated and bolts torqued evenly. Always install test cocks and shut-off valves per local plumbing codes. Consult the manufacturer's installation manual for specific torque values.

Used in

Common applications for Watts
Industrial burner gas safety systems — Watts HF2000 filters with GF-series seal kits maintain clean, regulated gas supply to burner pilot and main flame controls
Commercial heating and boiler installations — Modular filter assemblies support preventive maintenance and component replacement without full system shutdown
Process gas delivery pipelines — DN25 through DN125 filter bodies accommodate varying flow rates and inlet pressures across manufacturing and chemical processes
Gas pressure regulation benches — Multi-stage Watts filter platforms integrate with pressure reducers and safety shutoff valves in test and calibration environments
Equipment retrofit and upgrade projects — Available connection sizes and seal kits enable adaptation of newer Watts components into legacy gas control systems
Planned maintenance and spare-parts inventory — Filter seal kits allow facilities to stock consumables in advance, reducing downtime during scheduled gas system servicing

Watts Products

3G Electric supplies Watts watts double check backflow preventers. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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