Product Knowledge | Basic Information on the JW-LOK Three-Piece Ball Valve

Release date:

2026-05-21

A three-piece ball valve is an industrial valve that controls the flow of a medium by rotating a spherical plug. Its defining feature is that the valve body consists of three separate sections, facilitating on‑line maintenance and enabling operation under high‑pressure conditions.

A three-piece ball valve is a type of… An industrial valve that controls the flow of the working medium by rotating a spherical element, characterized by a three-piece valve body that facilitates on‑line maintenance and operation under high‑pressure conditions.

Working Principle of a Three-Piece Ball Valve

01. Three-Section Valve Body Design

The valve body is made of It consists of two valve bonnets on the left and right sides and a central valve body, which are clamped and secured from both ends by four long bolts. This design eliminates the need to dismantle the piping during maintenance; simply loosening the bolts allows the removal of the central valve body, facilitating the replacement of wear parts or the ball core.

02. Operating Principle of Opening and Closing

Example of BS Series 3-Way Valve Products

The closing member is a sphere, which is driven by the valve stem to rotate about the centerline of the valve body. Rotate 90° to open or close.

When enabled : The spherical passage is aligned with the pipeline, resulting in low fluid resistance; its drag coefficient is equal to that of a pipe section of the same length.

‌ When closed : The sphere vertically blocks the fluid flow, while an angular surface at the base of the valve stem mechanically wedges the sphere, pressing it tightly against the valve seat to achieve a seal.

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03. Core Advantages

Online Maintenance : The top-mounted design enables direct in-line inspection and maintenance, thereby reducing unit downtime.

Self-cleaning function : When the sphere tilts away from the valve seat, the fluid flows along the sealing surface. 360° uniform coverage ensures thorough rinsing, flushing away accumulated debris.

‌ Safety Design : The single‑seat design eliminates abnormal pressure buildup in the cavity, and certain designs incorporate an anti‑static device.

JW-LOK Product Specifications

JW-LOK’s BG and BS series three-piece ball valves are designed around the core principles of “safety and reliability, versatile compatibility, and precision durability.” Their structure and performance have been optimized to meet the practical demands of industrial applications, and the entire product line has undergone rigorous professional sealing tests, ensuring compliance with industrial‑grade standards.

01. Product Features

Category	Product Feature Description
Category	BG Series	BS Series
Structure	Adopts a blowout-proof stem design.	Adopts a three-piece precision casting structure
Performance	The valve allows bidirectional flow.	A 2-way valve allows flow in both directions; a 3-way ball valve can only use the bottom port as the inlet.
Test	Each valve is subjected to a leak‑tightness test using nitrogen or compressed air at its rated working pressure, with the requirement that no visible leakage be observed.
Optional equipment	-	Optional pneumatic or electric actuators are available.