Overview

The D71X lug-type fire butterfly valve is a valve that opens, closes, and regulates fluid flow by rotating a disc around its fixed shaft (stem). Its stem axis is also located at the "center line" where the center of the disc sealing surface intersects with the centerline of the pipeline passage, with the disc being symmetrical on both sides. The valve adopts a lug-type connection, meaning the valve body is designed with raised lugs containing threaded holes, allowing the valve to be secured between pipeline flanges using single-end bolts, and it can also be used as a pipe-end valve. The disc sealing ring is typically made of elastic materials such as rubber, directly embedded in the inner groove of the valve body or retainer plate, achieving sealing by the disc rotating and compressing the sealing ring. The valve can be driven manually, electrically, or pneumatically to rotate the stem by 90° or less, enabling quick control of fluid on/off and flow regulation. It is particularly suitable for fire protection systems and pipeline conditions requiring independent disassembly and maintenance.

D71X Lug Type Fire Butterfly Valve Product Drawing

Features:

1.Compact structure with end-of-line installation capability: The lug-type design features a valve body with raised lugs containing threaded holes, offering short structural length, small volume, and light weight. It is not only suitable for pipeline systems with limited installation space but can also be used independently as a pipe-end valve without the need for additional flanges or spool pieces.

2.Quick and convenient opening/closing: The disc rotates 90° to achieve full open or full close, providing simple and fast operation with low operating torque, facilitating manual or automatic actuation.

3.Low fluid resistance: When the disc is fully open, the media flow path is nearly a straight pipe, with minimal obstruction from the disc, resulting in low pressure loss and significant energy saving.

4.Good sealing performance: The center-line sealing structure allows the elastic soft sealing ring to closely contact the disc edge, achieving effective bidirectional sealing (or unidirectional sealing depending on specific design). It is particularly suitable for fire protection systems, water supply and drainage, and other normal temperature, normal pressure, or medium-low pressure conditions. Additionally, the lug-type connection enables online independent replacement of the valve without affecting the entire pipeline.

5.Easy maintenance and cost-effective: Simple structure with few components. The lug-type design allows independent valve disassembly, making inspection and replacement more convenient without removing adjacent pipes. Compared to other valves of the same size, manufacturing and installation costs are generally more advantageous.

6.Wide application, suitable for fire protection and industrial pipelines: The valve body can be made of various materials such as ductile iron and stainless steel, while the lining and disc can also be selected with different anti-corrosion materials or coatings. Widely used in fire protection systems, water treatment, air conditioning, water supply and drainage, chemical industry, and other liquid/gas media pipelines, especially meeting the fire protection code requirements for pipe-end valves and reliability.

D71X Lug Type Fire Butterfly Valve Structure Drawing

Parts Name and Materials Table

Performance Specification Table

D71X Lug Type Fire Butterfly Valve Overall Dimension Drawing

D71X Lug Type Fire Butterfly Valve Overall Dimension Table