The LIANHE Stainless Steel Square Plug and Hex Plug is designed to close and seal compatible female threaded pipeline openings. Available with square-head and hex-head configurations, the product supports convenient installation, tightening, removal, inspection, and pipeline maintenance.
Manufactured from cast stainless steel, the threaded plug provides good mechanical strength, corrosion resistance, and long-term durability. Male threaded connections are available according to NPT, BSPT, BSP, DIN 2999, and ISO 228 specifications.
Multiple stainless steel grades, sizes, thread standards, surface treatments, and customized marking options are available to meet industrial, commercial, residential, water-treatment, and pharmaceutical piping requirements.
Product Types:
Stainless Steel Square-Head Plug
Stainless Steel Hex-Head Plug
Size Range: 1/8"–4" (DN6–DN100)
Pressure Rating: Class 150
Applicable Standards: ISO 4144, MSS SP-43, and GB/T 26120
Connection Type: Male Threaded Connection
Available Thread Standards: NPT, BSPT, BSP, DIN 2999, and ISO 228
Manufacturing Process: Stainless Steel Casting and Thread Machining
Available Materials:
SS201
SS304 and CF8
SS316 and CF8M
SS316L
Other stainless steel grades upon request
Surface Treatment: Pickling
Product Marking: Size + Material Grade + Class 150. Customer logos, private brands, batch information, and other customized markings can be applied according to specific requirements.
Standard Packaging: Plastic Packaging, Export Cartons, Wooden Cases, or Pallets
Certificates: GB/T 19001-2016, ISO 9001:2015, and CE documentation for applicable products
Brand: LIANHE
Place of Origin: Wenzhou, Zhejiang, China
The final dimensions, material grade, pressure rating, and thread standard should be confirmed according to the intended application and mating female threaded connection.
The square-head design provides an external driving surface for installation and removal using a compatible wrench or tool. It is suitable for applications requiring a compact and practical threaded closure.
The hex-head design allows the plug to be tightened or removed using a standard compatible wrench or socket. It provides convenient tool engagement during pipeline assembly, inspection, and maintenance.
Customers should select the appropriate head type according to the available installation space, tool access, tightening requirements, and maintenance conditions.
The stainless steel threaded plugs can be used with compatible liquid and gaseous media, including:
Water
Oil and compatible liquid media
Gas and compatible gaseous media
Diluted acids and compatible chemical media
Material and thread-sealing compatibility should be evaluated according to the transported medium, chemical concentration, operating temperature, system pressure, and required service life.
SS304, SS316, and SS316L provide different levels of corrosion resistance. The appropriate material should be selected according to the actual service environment.
The products can be used to close unused threaded outlets, pipeline branches, valve openings, equipment ports, inspection connections, and other compatible female threaded interfaces.
Typical application areas include:
Industrial piping systems
Water supply and treatment systems
Household water installations
Commercial building pipelines
Oil and compatible fuel systems
Gas systems using approved materials and sealing methods
Pharmaceutical equipment and facility piping
Chemical-processing equipment
Environmental protection systems
Machinery and instrument connections
General fluid-control applications
For pharmaceutical, fuel-gas, chemical, or other regulated applications, customers should confirm whether additional material documentation, surface treatment, testing, or certification is required.
Square-head and hex-head configurations available
Durable cast stainless steel construction
Good mechanical strength and dimensional stability
Excellent corrosion and oxidation resistance
Multiple thread standards available
Convenient installation and removal
Suitable for pipeline closure and equipment maintenance
Multiple stainless steel grades available
Pickled surface treatment
Customized product markings supported
OEM production according to customer drawings
Export packaging suitable for international transportation
The male threaded connection allows the plug to be installed into a compatible female threaded opening. An appropriate thread sealant, sealing tape, or sealing compound should be selected according to the thread standard, transported medium, working pressure, and operating temperature.
NPT, BSPT, BSP, DIN 2999, and ISO 228 threads may have different profiles, taper characteristics, pitch dimensions, and sealing methods. They should not be used interchangeably unless compatibility has been technically confirmed.
The product body is manufactured through stainless steel casting, followed by machining of the male thread and critical dimensions.
The principal manufacturing procedures may include:
Raw-material preparation
Casting
Casting cleaning
Heat treatment, where required
Dimensional machining
Thread processing
Pickling
Product inspection
Marking and packaging
Pickling helps remove surface contamination, heat tint, scale, and free iron introduced during casting and machining. Additional surface-treatment options may be discussed according to customer requirements.
Standard markings may include:
Product size
Stainless steel material grade
Class 150 pressure designation
LIANHE logo
Batch or traceability information, when required
Customer logos, private brands, project numbers, and other customized markings can be applied according to confirmed order requirements.
LIANHE assigns quality-control personnel to the relevant stages of production. Inspection procedures are performed during manufacturing, machining, thread processing, surface treatment, marking, and packaging.
The principal quality-control procedures include:
Raw-material grade and documentation inspection
Casting appearance and dimensional inspection
Critical dimension measurement after machining
Thread profile, size, and gauge inspection
Surface-condition inspection after pickling
Product marking and specification verification
Final inspection according to the confirmed order
Quantity, packaging, label, and shipping-mark inspection
Products are approved for delivery after completing the applicable inspection procedures.
Additional PMI testing, dimensional reports, pressure testing, thread inspection reports, material certificates, or third-party inspection can be arranged according to project requirements.
OEM orders are accepted. Products can be manufactured according to customer drawings, samples, technical specifications, thread requirements, material grades, product markings, and packaging instructions.
Customers requesting customized production should provide:
Product drawing or sample
Head type
Thread type and size
Stainless steel material grade
Working pressure and temperature
Transported medium
Required quantity
Inspection requirements
Marking and packaging instructions
Production feasibility, tooling requirements, minimum order quantity, price, and delivery schedule will be confirmed after technical review.
Each product is protected with plastic packaging to reduce exposure to dust, moisture, and surface contamination.
Products are then packed in reinforced export cartons and consolidated in wooden cases or on pallets according to the order quantity and transportation method.
Customized cartons, customer logos, labels, barcodes, pallet protection, and other packaging arrangements can be provided according to confirmed requirements.
Our standard payment term is a 30% T/T deposit paid in advance, with the remaining 70% T/T balance paid before shipment. Specific payment arrangements can be negotiated according to the order value and cooperation conditions.
Available payment methods include:
T/T bank transfer
Western Union
PayPal
Other mutually agreed methods
Available Trade Terms: EXW, FOB, CFR, CIF, DDP, and DDU
Products can be delivered by:
Sea freight
Air freight
Land transportation
International express service
Wenzhou, Ningbo, and Shanghai ports are conveniently accessible. Products can also be transported to a customer-designated destination according to the confirmed shipping arrangement.
The shipping method can be selected according to the order quantity, package volume, destination, delivery schedule, and transportation budget.
Manufacturer: LIANHE
Place of Origin: Wenzhou, Zhejiang, China
Address
Building 2, No.3991, Binhai 3 Road, Wenzhou Economic Technological Development
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