Hexagonal Cap with Inner Thread

The female thread hexagonal pipe cap (hex plug) is a dedicated pipeline sealing fitting with external hexagonal profile and internal female thread. It mates perfectly with male threaded pipe ports to achieve reliable temporary or permanent pipeline blocking.

The hexagonal outer profile enables wrench/socket operation for fast installation & disassembly without slipping. Combined with PTFE tape or thread sealant, it delivers leak-tight sealing for water, gas, heating and industrial fluid pipelines. Available in carbon steel, SS304/SS316 stainless steel and brass, it covers low to high corrosion, temperature and pressure working environments. Standard DN15-DN32 sizes plus custom machining support valve, instrument and manifold spare port sealing.

1. Hex Anti-Slip Installation Structure

Six-sided hexagonal outer body provides stable force bearing points for open-end wrenches and socket tools. Compared with round caps, it eliminates tool slipping during tightening, speeds up construction and avoids thread damage caused by uneven force.

2. Precision Female Thread Sealing

• High-precision CNC turned internal thread matches standard male pipe threads (BSP/G / NPT) for tight thread fit.
• Extra sealing auxiliary: PTFE tape or liquid sealant can be wrapped on threads to enhance sealing performance, zero leakage under rated working pressure.
• Single-end sealing design, specially for blocking unused male-thread pipe ports, not for connecting two pipes.

3. Multi-Material Corrosion Resistance

• SS304 / SS316 Stainless Steel: Pass 500h+ neutral salt spray test, anti-rust for coastal humid, chemical corrosive, outdoor heating systems.
• H59 Brass: Good ductility, low friction, ideal for domestic plumbing, drinking water pipeline.
• Hot-dip Galvanized Carbon Steel: High compressive strength, cost-effective for general industrial water & gas pipelines.

4. Long Service Life & Wide Compatibility

Solid one-piece forming structure without easy deformation, stable under 0~120℃ temperature cycling and PN16 nominal pressure. Standard DN15, DN20, DN25, DN32 dimensions match mainstream pipe fittings, valves and manifold interfaces; custom thread size, wall thickness and surface polishing are supported for special engineering projects.

1. Plumbing & Underfloor Heating

Seal spare ports of floor heating water manifolds, temporary block pipelines during pressure testing, long-term sealing of unused domestic water pipe outlets.

2. Gas Pipeline Systems

Seal spare male-thread interfaces of gas valves and meters, safe blocking for natural gas pipeline renovation.

3. Industrial Chemical & Fluid Equipment

Block spare ports of pressure gauges, flow meters and hydraulic equipment; anti-corrosion sealing for factory corrosive medium pipelines.

4. Outdoor & Coastal Engineering

Rust-proof stainless steel caps for agricultural irrigation pipelines, seaside building heating and water supply systems.

Pipeline Connection and Blockage
Pipeline Connection: Female thread hex caps are commonly used in pipeline systems as connectors to join two male threaded pipelines, enabling pipeline extension and redirection. For example, in water supply/drainage, gas, and chemical pipeline systems, they can conveniently connect pipelines of different directions or specifications to ensure normal system operation.
Pipeline Blockage: When a section of pipeline is unused or requires maintenance, female thread hex caps can block pipeline ports to prevent medium leakage. This blocking method is simple and effective, suitable for various temporary or long-term blocking needs.
Equipment Interface Connection
Connecting Valves, Instruments, etc. : In industrial production and equipment installation, female thread hex caps are used to connect valves, pressure gauges, flow meters, and other equipment to pipeline systems. By connecting to the male threaded interfaces of equipment, they enable easy installation of equipment on pipelines to control, measure, and monitor media in the pipeline system.
Equipment Maintenance and Replacement: The convenient disassembly feature of female thread hex caps simplifies equipment installation and removal during maintenance or repla

1. Clean the external male thread of the pipe port to remove rust, dirt and burrs.

2. Wind PTFE tape evenly clockwise on the male thread or apply thread sealant.

3. Screw the hex cap onto the pipe port by hand first, then use a wrench to tighten moderately (avoid over-tightening causing thread cracking).

4. Check sealing status after installation: no medium seepage under normal pipeline pressure.