Stainless Steel Pipe Cap
The stainless steel pipe caps we produce are used for terminal sealing of industrial piping systems, and common names include stainless steel heads, pipe plugs, and end caps. The product materials cover 304, 304L, 316, 316L, 321, 310S, as well as 2205 and 2507 duplex stainless steel, and can correspond to standards such as GB/T12459, ASME B16.9, DIN2617, EN10253, JIS B2312, and GOST17379. Specifications range from DN15 to DN2000, 1/2″ to 48″, and the wall thickness systems include SCH10S, SCH40S, SCH80S, and SCH160S. Pressure ratings cover PN10–PN100, Class150–1500, and 5K–40K, and the operating temperature range is -196℃ to 700℃. Forming methods include seamless hot pressing, steel plate rolled and welded construction, and precision forging. Before purchasing, it is recommended to confirm the medium type, cleanliness level, temperature and pressure, required standards, and material, and we will assist in matching specifications and providing a quotation accordingly.
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Alloy Steel Pipe Cap
Alloy steel pipe caps, also known as heat-resistant alloy heads or high-pressure alloy plugs, are high-pressure and high-temperature plugging pipe fittings smelted and formed by adding alloying elements such as chromium, molybdenum, and vanadium on the basis of carbon steel. The products cover DN15–DN2000, 1/2″–48″ imperial inch diameters, wall thicknesses ranging from SCH40 to XXS, and pressure ratings covering Class300–Class2500 and PN63–PN160. Materials include 15CrMo, 12Cr1MoV, Cr5Mo, 10CrMo910, P11, P12, P22, P91 and other heat-resistant chromium-molybdenum alloy steels, and they comply with standards such as GB/T12459, ASME B16.9, and ASTM A234. The production processes are divided into seamless hot-pressed integrated forming, thick plate rolled and welded forming, and precision forging forming, followed by normalizing and tempering heat treatment to eliminate stress. They are mainly used for permanent end sealing, zoned isolation, and pressure test sealing of pipelines such as high-temperature steam main lines, boiler pipelines, thermal power generating units, and petrochemical hydrogenation units.
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Duplex Steel Pipe Cap
Duplex steel pipe caps adopt an austenitic plus ferritic duplex metallographic structure, with materials covering grades such as 2101, S31803, 2205 (S32205/F51), 2507 (S32750/F53), and S32760, and are subjected to solution annealing treatment. Specifications range from DN15 to DN2000, or 1/2″ to 48″ in imperial units, and can match SCH10S, SCH40S, SCH80S, and SCH160S wall thicknesses as well as PN10–PN100 and Class150–Class1500 pressure ratings, and comply with standards such as GB/T21832, ASTM A815, ASME SA815, EN, DIN, JIS, and GOST. They are mainly used for end capping, spare nozzle closure, and zone isolation of offshore platform pipelines, seawater desalination equipment, coastal chemical pipeline networks, sour oil and gas transportation, desulfurization and denitrification environmental protection equipment, and brine and salt chemical pipelines. Before procurement, it is recommended to confirm the chloride ion concentration of the medium, hydrogen sulfide content, acid-base environment, diameter, wall thickness, pressure rating, and the required material grade, and we will assist in matching solutions such as 2205 or 2507 accordingly.
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National Standard Stub End
National standard lap joint stub end, also called lap joint short pipe, loose flange lap ring, or lap joint, is a pipe fitting used in national standard piping systems together with loose flanges. During installation, the loose flange slides freely on the stub end body, and tightening the bolts only presses the lap end face to complete the seal. The pipe body does not bear the torsional stress of the flange, so it is suitable for pipelines that require regular disassembly and maintenance. Product specifications cover DN15~DN2000, imperial 1/2″~48″, wall thickness follows the SCH standard series, and can adapt to PN10~PN160 pressure ratings. Materials include carbon steel, stainless steel, alloy steel, and duplex steel. There are three production processes: seamless hot-pressed lap, steel plate rolled lap, and forged machined lap. The lap end face is flat, and the rounded corner transition is smooth. We can confirm specific specifications, materials, and quantities according to project requirements. Welcome to contact us for a quotation.
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ASME Stub End
American standard lap joint stub ends are integrally formed by a straight pipe section and an outwardly flanged lap ring at the end, welded to the pipe end, and paired with American standard loose flanges to form a detachable connection. The loose flange can rotate freely on the pipe body; when the bolts are tightened, it only presses the flanged end face to achieve sealing, and the pipe body itself does not bear the torsional stress of the flange, making later disassembly and maintenance convenient. Product specifications cover NPS1/2 to NPS48, wall thicknesses include the SCH series and the XXS thickened series, and pressure ratings are compatible with Class150 to Class2500. Raw materials use A234 WPB carbon steel, A403 stainless steel, A182 series alloy steel, and 2205/2507 duplex steel; forming processes include seamless hot pressing, steel plate rolling and welding, and forged machining. The flanged rounded transition is smooth, the end face is flat, and dimensional tolerances are controlled according to American standard requirements, allowing interchangeability and pairing with loose flanges of the same standard.
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European standard lap joint stub end
The European standard lap joint stub end is a matching pipe fitting in the European standard lap joint flange connection system, with the English name Lap Joint Stub End, implemented according to EN 10253 and DIN 2642 standards. Structurally, it is integrally formed by a straight pipe section and an outwardly flanged ring formed at the end, and is welded to the pipe end; the lap joint flange can rotate freely on the stub end body, and when the bolts are tightened, only the flanged end face is pressed to achieve sealing, so the pipe body does not bear the torsional stress of the flange, which facilitates later pipeline disassembly, inspection, and maintenance. Product specifications cover DN15–DN2000, with corresponding outer diameters according to the EN/DIN European standard pipe outer diameter system; wall thicknesses include S series and SCH series, suitable for PN6 to PN160 European standard pressure ratings. Raw materials use European standard grade steel, including P265GH carbon steel, 1.4301/1.4404 stainless steel, 13CrMo44 alloy steel, 1.4462 (2205), and 1.4507 (2507) duplex steel. Forming processes include seamless hot-pressed flanging, steel plate rolling and welding, and forged machining. The flanged rounded transition is smooth, the end face is flat, and dimensional tolerances follow European standard specifications, allowing interchangeability and matching with European standard lap joint flanges of the same specifications worldwide.
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Japanese standard lap joint stub end
The Japanese standard lap joint stub ends we produce are manufactured in accordance with the JIS B2321 Japanese Industrial Standard, and are integrally formed from a straight pipe section and an end external flared sealing ring. During installation, the pipe body is butt-welded to the pipeline, and is matched with a Japanese standard loose flange that slides, rotates, and locks freely, without the need to rotate the pipe body itself, which can reduce the torsional stress and high-altitude alignment deviation caused by traditional welded flanges. The product nominal diameter adopts the Japanese A series specifications, covering 15A–1500A, the wall thickness includes the STD, XS, and SCH series, and the pressure ratings cover 5K, 10K, 16K, and 20K. The materials are Japanese standard dedicated grades, including SS400 carbon steel, SUS304/SUS316L stainless steel, STPA23/STPA24 alloy steel, and SUS329 duplex steel. The forming processes are divided into three categories: seamless hot pressing, rolled and welded, and forged machining. The flared rounded corner transition is uniform, the end face is flat, and the dimensional tolerances and groove angles are controlled according to Japanese standard requirements, allowing interchangeability with Japanese standard flanges of the same specifications worldwide.
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DIN standard lap joint stub end
The German standard lapped stub end is integrally formed by a straight pipe section and an end flared ring shaped by outward flaring. During construction, the pipe body is butt-welded to the pipeline, and the loose flange can rotate freely on the stub end pipe body. When the bolts are tightened, only the flared end face is pressed to achieve sealing, and the pipeline body does not bear the torsional stress of the flange, which facilitates later pipeline disassembly and maintenance. The product's nominal diameter covers DN15–DN2000 and adopts the German standard pipe outer diameter system; the wall thickness includes the S series and SCH series, adapting to German standard pressure ratings PN6, PN10, PN16, PN25, PN40, PN63, PN100, and PN160. The raw materials use German standard grade steel, including P265GH carbon steel, 1.4301/1.4404 stainless steel, 13CrMo44 alloy steel, 1.4462 (2205), and 1.4507 (2507) duplex steel. The forming processes include seamless hot-pressed flaring, steel plate rolling and welding, and forged machining. The flared fillet transition is smooth, the end face is flat, and the dimensional tolerances follow DIN specifications, allowing interchangeable matching with German standard loose flanges of the same specifications worldwide.
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Non-standard stub end
Non-standard lap joint stub ends do not have fixed standard specifications under national standards, American standards, European standards, or Japanese standards. The pipe body is butt welded, the end is flared outward for sealing, and with a backing flange it can rotate freely and lock tightly. During installation, it can avoid pipeline torsional stress and weld seam cracking. The product has no fixed restrictions on nominal diameter, wall thickness, length, or pressure rating, and can process non-standard sizes within the range of DN10–DN3000, supporting special-shaped structures such as ultra-short, ultra-long, thickened, thinned, eccentric, reducing, and widened sealing surface. Materials cover carbon steel, the full series of stainless steel, chrome-molybdenum alloy steel, 2205/2507 duplex steel, and special corrosion-resistant alloys. Processes include seamless special-shaped hot pressing, large steel plate rolling, and precision forging machining. We produce according to drawings or measured data, with MOQ as low as 1 piece, and conventional simple non-standard structures are delivered within 3–5 working days after drawing confirmation. For specific dimensions, materials, and working condition adaptation solutions, please contact us for confirmation.
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