Stainless Steel Square Plug and Hex Plug

Product Description

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.

Technical Specifications

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.

Product Types

Square-Head Plug

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.

Hex-Head Plug

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.

Applicable Media

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.

Product Applications

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.

Product Features and Advantages

1. Square-head and hex-head configurations available

2. Durable cast stainless steel construction

3. Good mechanical strength and dimensional stability

4. Excellent corrosion and oxidation resistance

5. Multiple thread standards available

6. Convenient installation and removal

7. Suitable for pipeline closure and equipment maintenance

8. Multiple stainless steel grades available

9. Pickled surface treatment

10. Customized product markings supported

11. OEM production according to customer drawings

12. 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.

Manufacturing and Surface Treatment

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:

1. Raw-material preparation

2. Casting

3. Casting cleaning

4. Heat treatment, where required

5. Dimensional machining

6. Thread processing

7. Pickling

8. Product inspection

9. 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.

Product Marking

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.

Product Quality Control

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:

1. Raw-material grade and documentation inspection

2. Casting appearance and dimensional inspection

3. Critical dimension measurement after machining

4. Thread profile, size, and gauge inspection

5. Surface-condition inspection after pickling

6. Product marking and specification verification

7. Final inspection according to the confirmed order

8. 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 and Customized Production

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.

Packaging

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.

Payment Terms

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

Shipping Terms

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