China Soft Sealing Non-Lubricated DBB Plug Valves Manufacturers, Suppliers and Factory

Product Introduction

Soft Sealing Non-Lubricated DBB Plug Valves are engineered for high-integrity isolation, zero-leakage performance, and long-term maintenance-free operation in demanding industrial systems. Designed in strict accordance with international standards such as API 6D and API 599, these valves provide a compact, single-valve solution for double block and bleed (DBB) applications in oil & gas, petrochemical, and process industries. Unlike traditional lubricated plug valves, our non-lubricated design eliminates grease injection, eliminating contamination risks and ensuring stable sealing under extreme conditions.

Pneumatic Actuated Non-Lubricated DBB Valve
The Pneumatic Actuated Non-Lubricated DBB Valve is engineered for critical isolation and safety-venting applications. By combining two independent sealing barriers with an intermediate bleed system

view more
Stainless Steel Non-Lubricated DBB Valve
Our non-lubricated Double Block & Bleed (DBB) valve integrates two independent sealing barriers and a central bleed port within a single, compact body. This engineered design allows operators to

view more
Carbon Steel Soft Seat DBB Plug Valve
The Carbon Steel Soft Seat Double Block and Bleed (DBB) Plug Valve is engineered for high-integrity, bubble-tight shutoff in critical industrial piping systems. Utilizing a quarter-turn plug

view more
Flanged Soft Sealing Non-Lubricated Valve
The Flanged Soft Sealing Non-Lubricated Plug Valve is engineered for heavy-duty, reliable flow isolation in severe process environments. Utilizing a premium resilient soft seat combined with a

view more
Non-Lubricated Soft Seat DBB Plug Valve
Non-Lubricated soft seat DBB plug valve operates on a precise quarter-turn rotary motion. The tapered or cylindrical plug rotates smoothly inside a premium polymer-lined sleeve. This design achieves

view more
Soft Sealing Non-Lubricated DBB Plug Valve
Our Soft Sealing Non-Lubricated DBB (Double Block and Bleed) Plug Valve is engineered to deliver bubble-tight isolation, zero-leakage shutoff, and maintenance-free operation in demanding upstream,

view more

Why Choose Our DBB Plug Valve

True Double Block and Bleed (DBB) Functionality
A single valve body integrates dual isolation seals (upstream and downstream) and an intermediate cavity venting system (bleed port). This design allows operators to verify seal integrity and safely release cavity pressure before performing downstream maintenance.
Zero-Leakage Soft Sealing System
Utilizing premium, reinforced elastomeric and thermoplastic inserts, the valve achieves:

Bubble-tight sealing compliant with API 598 pressure testing standards.
Reliable bi-directional sealing under both low-pressure micro-leakage and high-pressure surge conditions.
High resistance to abrasive particles and volatile media.

Non-Lubricated Design = Maintenance-Free Operation

Traditional lubricated plug valves require continuous grease injection to maintain their seal and prevent seizing. Our non-lubricated design completely rewrites this process:

Zero Contamination

Ideal for clean media, gas pipelines, and automated or unmanned installations.

No Seal Degradation

Eliminates the risk of sealant hardening, washing out, or locking the plug.

Lower Total Cost of Ownership (TCO)

Significantly reduces routine field maintenance and lifecycle expenditures.

Specifications

Performance Aspect	Our Single DBB Plug Valve	Traditional Dual-Valve System
Installation Space	Compact & Lightweight	Large & Bulky
Potential Leak Points	Minimal (Single Body)	Multiple (Flanges & Joints)
Maintenance Frequency	Extremely Low	High (Two separate valves)
System Complexity	Simple, Streamlined Piping	Complex layout with bypass/bleed
Total Procurement Cost	Lower (Reduced labor & fittings)	Higher

Technical Specifications & Engineering Data

Size Range: DN50 – DN600 (2" – 24")

Pressure Class: ASME Class 150 / 300 / 600

Body Materials: Carbon Steel (WCB, LCC), Stainless Steel (CF8, CF8M), Duplex & Super Duplex Stainless Steel (4A, 5A)

Plug & Stem Materials: A105+ENP, F304, F316, Monel

Seat/Insert Materials: PTFE, RPTFE, Devlon, PEEK, Viton (Elastomer Reinforced)

End Connections: Flanged (RF, RTJ), Butt-Weld (BW)

Operation: Manual Lever, Heavy-Duty Gearbox, Pneumatic, or Electric Actuator

Temperature Range: -29°C to +200°C (depending on soft seal material selection)

Flanged Soft Sealing Non-Lubricated Valve

International Compliance & Certifications

Our valves are manufactured and certified to meet the highest global standards:

API 6D – Pipeline Valves

API 599 – Metal Plug Valves

API 598

Testing and Inspection (100% Hydrostatic & Low-pressure Air Testing)

API 607 / API 6FA

Fire Safe Certified

NACE MR0175 / ISO 15156

Materials for Use in H2S-Containing Environments (Sour Service)

Typical Critical Applications

Oil & Gas Transmission

Pipeline block isolation, metering and fiscal transfer stations, pig launcher and receiver traps.

Refining & Petrochemical

Hydrocarbon processing loops, refinery unit isolation, catalyst/reactor feed and discharge systems.

Chemical Processing

Corrosive chemical transport, toxic fluid handling, and aggressive acid/alkali control lines.

Power Utilities

High-pressure cooling water circuits, condensate lines, and industrial steam systems.

Manufacturing Quality Assurance

Every single valve undergoes a rigorous quality control program before leaving our facility to ensure zero-defect performance in the field:

Material Verification

Positive Material Identification (PMI) and ultrasonic testing on all castings/forgings.

Precision Machining

CNC-machined plug and body surfaces ensuring ultra-tight geometric tolerances.

Controlled Assembly

Soft seats inserted in dust-free environments to eliminate debris contamination.

Pressure Testing

100% hydrostatic shell and seat testing, plus low-pressure gas testing per API 6D / API 598.

Final Inspection

Complete dimensional, coating thickness, and visual audits.

FAQ

Q: Can this single DBB plug valve fully replace a traditional two-valve-and-bleed-spool setup?

A: Yes, absolutely. It is explicitly designed to replace dual-valve configurations. It achieves the exact same independent double-isolation and venting functions within a single, space-saving valve body, reducing both structural weight and piping leak paths.

Q: What makes the non-lubricated design safer for gas pipelines?

A: In gas systems, traditional sealants and grease can be washed away or carried downstream, causing process contamination or valve sticking. Our non-lubricated design relies on mechanical soft sealing (e.g., PTFE/Devlon), ensuring bubble-tight shutoff without relying on injected grease, making it safer for critical gas services.

Q: Are these valves suitable for sour service (H2S) environments?

A: Yes. When specified, we manufacture the valve bodies and internal trims fully compliant with NACE MR0175 / ISO 15156 standards to resist sulfide stress cracking (SSC).

Find professional soft sealing non-lubricated dbb plug valves manufacturers and suppliers in China here! With abundant experience, we warmly welcome you to buy high quality soft sealing non-lubricated dbb plug valves made in China here from our factory. Customized orders are welcome.

dbb plug valve, double block and bleed gate valve, twin seal double block and bleed valve