This Part of EN 10253 specifies the technical delivery requirements for seamless and welded butt-welding
fittings (elbows, concentric and eccentric reducers, equal and reducing tees, caps) made of carbon and alloy steel which are intended for pressure purposes at room temperature, at low temperature or at elevated temperatures, and for the transmission and distribution of fluids and gases.

 

It specifies:
type of fittings ;

type A : Butt-welding fittings with reduced pressure factor ;
type B : Butt-welding fittings for use at full service pressure ;

steel grades ;

mechanical properties ;
dimensions and tolerances ;
requirements for inspection and testing ;
inspection documents ;
marking ;
protection and packaging.

NOTE In the case of a harmonised supporting standard for materials, presumption of conformity to the ESRs is limited
to technical data of materials in the standard and does not presume adequacy of the material to a specific item of
equipment. Consequently it is essential that the technical data stated in the material standard be assessed against the
design requirements of this specific item of equipment to verify that the ESRs of the PED are satisfied.

A:  Quality management system of our company conform to the Quality Management System Standard: GB/T 19001-2008 / ISO 9001:2008.

 

Q: What is your terms of payment ?

A: 1. 30% T/T in advance, the balance against the copy of B/L.

     2. 100% L/C at sight.

 

 

Production Process:

• Material Selection: We primarily source raw materials from leading steel mills such as Baosteel, TPCO, Yanbao, Baotou Steel, Changbao, and Huarun. We select tubes with smooth internal/external surfaces, uniform wall thickness, and a preference for higher manganese content to ensure a superior final appearance.

• Material Inspection: Incoming materials undergo dimensional checks and chemical composition analysis.

• Warehousing: Approved materials are stored in inventory.

• Cutting: Tubes are cut to length with sufficient machining allowance. Burrs and metal chips are removed.

• Bending & Forming: Tubes are heated using medium-frequency induction heaters and formed via pushing with precision dies. Dies are re-polished every 48 hours of operation to maintain strict dimensional tolerances.

• Heat Treatment: Stress relief annealing (tempering) is performed.

• End Machining: Bevels are cut on 90-degree CNC lathes to an angle of 37.5° ± 0.25°. The land (flat edge at the end of the bevel) is sized according to the pipe diameter. The land ensures a flush fit for butt welding and prevents burn-through during the TIG root pass.

• Visual Inspection: Surfaces are checked for defects like scratches, peeling, or pitting.

• Chemical Analysis: Composition is verified using imported handheld spectrometers.

• Dimensional Inspection: Checks include outside diameter, wall thickness, ovality, and straightness.

• Mechanical Testing: Tests include flattening and flaring to validate performance.

• Sandblasting: A fine grit is used to create a uniform surface finish without excessive pitting.

• Painting: Surfaces are evenly coated using environmentally friendly spray equipment.

• Marking: Legible black background with white lettering is applied using a marking machine.

• Packaging: Products are packed in wooden cases or on pallets, secured with steel strapping, and wrapped in plastic film for weather and dust protection.

• Shipping: Careful handling using forklifts and overhead cranes ensures secure and orderly loading for transport.

Quality Assurance & Company Profile:

1. Certifications: ISO 9001 Quality Management System, Environmental Management System, Occupational Health & Safety Assessment Series, AAA Credit Rating, and SGS International Certification.

2. Quality Control: An integrated international ERP system manages production, supplemented by a secondary manual quality inspection to guarantee a 100% pass rate.

3. Production Capacity: Annual output of 20,000 tons of pipe fittings.

4. Facilities & Workforce: 7,000 sqm storage warehouse and a team of 200 employees.

5. R&D & Customization: A 300 sqm sample room supports our in-house R&D and ODM/ custom manufacturing capabilities.

6. Service: We offer straightforward cooperation, responsive service, and efficient logistics.

7. Experience: A decade of expertise in international export.