Low-temperature steel pipe cap

Low-temperature steel pipe caps are the terminal core sealing and pressure-bearing pipe fittings of low-temperature cryogenic pipeline systems, specifically used for pipeline end closure, pressure test sealing, spare pipe opening isolation,

Low-temperature steel pipe cap - Low-temperature steel pipe caps exclusively adapted for high-end industrial pipeline...

Low-temperature steel pipe cap

Low-temperature steel pipe caps are the terminal core sealing and pressure-bearing pipe fittings of low-temperature cryogenic pipeline systems, specifically used for pipeline end closure, pressure test sealing, spare pipe opening isolation,

Reference Price

Inquiry

  • The core advantages of low-temperature steel pipe caps are low-temperature resistance without brittle cracking, high toughness at deep cryogenic temperatures, high-pressure stability, stress-relief and crack resistance, full inspection qual
  • they are deep-cryogenic special-purpose pipe fittings that ordinary carbon steel pipe caps cannot replace. All products use WPL6, 16MnDG, and Q345E low-temperature special-purpose base materials
  • different from ordinary 20# and Q235 carbon steel
  • Excellent low-temperature impact toughness
  • in a deep-cryogenic environment of -40℃ to -46℃, they do not undergo cold brittleness, do not crack, and do not fail. All undergo professional low-temperature heat treatment for stress relief
Quote View Details

Detailed Introduction

Low-temperature steel pipe caps are also called low-temperature heads or low-temperature pipe plugs. They are installed at the end of pipelines for closure, hydrostatic test blind plugs, or isolation of spare pipe openings. Unlike ordinary carbon steel pipe caps, they use WPL6, 16MnDG, and Q345D/E low-temperature special base materials, undergo stress relief heat treatment and low-temperature impact testing, and are not prone to cold brittle cracking under -46°C deep cryogenic working conditions. Products are manufactured according to ASME B16.9, GB/T12459, and ASTM A420 standards, covering DN15–DN1200, SCH20–XXS, Class150–Class900, with connection methods including butt welding, socket welding, and threading. Before leaving the factory, low-temperature impact testing, hydrostatic pressure testing, and non-destructive testing are performed, and material MTC, impact reports, and inspection reports are provided with the goods. Regular specifications have a minimum order quantity of 1 piece, WPL6 and 16MnDG mainstream models are in stock, and non-standard sizes, special wall thicknesses, and ultra-low-temperature process customization are also accepted.

  • Uses WPL6, 16MnDG, and Q345D/E low-temperature special steel, different from ordinary 20# and Q235 carbon steel, maintaining low-temperature impact toughness in a -46°C deep cryogenic environment
  • Through quenching and tempering and stress relief heat treatment, reduces forming internal stress and lowers the risk of low-temperature stress cracking
  • Integrated molded seamless forming, uniform wall thickness, balanced pressure bearing, suitable for pipeline end sealing and hydrostatic test blind plugs
  • Low-temperature impact testing, hydrostatic pressure testing, and non-destructive testing are performed before leaving the factory, and material MTC, impact reports, inspection reports, and certificates of conformity are provided with each batch
  • Covers DN15–DN1200, SCH20–XXS, Class150–Class900, supports multiple connection forms including butt welding, socket welding, and threaded NPT/BSP
  • Regular standard specifications have a minimum order quantity of 1 piece, WPL6 and 16MnDG mainstream models are kept in stock, and can support engineering replacement parts and urgent construction milestones
  • Supports customization of non-standard overall height, special curvature, special bevels, thickened pressure bearing, and -60°C ultra-deep cryogenic processes, and can be equipped with English laser marking and project-specific packaging
Product NameLow-Temperature Steel Pipe Cap
Product CategoryPipe Cap
The parameters of this series of low-temperature steel pipe caps fully comply with ASME B16.9, ASTM A420, and GB/T12459 international low-temperature pipe fitting standards, and are suitable for global cryogenic engineering design and special equipment acceptance specifications. Core low-temperature materialsWPL6 (resistant to -46℃), 16MnDG (resistant to -40℃), Q345D/Q345E (extreme cold low-temperature impact). Nominal diameter DN15–DN1200 (NPS1/2–NPS48), structures include 2:1 elliptical, hemispherical, spherical crown, and flat bottom types. Wall thickness grades SCH20, SCH40, SCH80, SCH160, XXS super extra heavy; pressure ratings suitable for PN10–PN160, Class150–Class900. Connection forms: butt welding, socket welding, threaded NPT/BSP. Applicable media: LNG, liquid nitrogen, liquid oxygen, low-temperature process gas, extreme cold air media. Working temperature range -46℃～100℃, ensuring low
CustomizationOur factory possesses full-dimensional high-end precision customization capability for low-temperature steel pipe caps, and can undertake various global cryogenic non-standard size, special wall thickness, special curvature, ultra-low-temperature strengthening, and high-pressure special-shaped customization orders. Supports customization of non-standard total height, non-standard curvature, special bevels, thickened pressure-bearing, and special-shaped flat bottom structures, suitable for old low-temperature pipe network renovation, non-standard pipe opening connection of imported equipment, and installation conditions with limited space in narrow pipe galleries. Can customize the full range of low-temperature materials WPL6, 16MnDG, Q345E as needed, can strengthen ultra-low-temperature impact performance, and customize minus 60℃ ultra-deep cryogenic process treatment. Supports customization of ultra-large-diameter rolled low-temperature pipe caps, ultra-thickened high-pressure pipe caps, and hemispherical high-pressure special-shaped plugging pipe fittings, suitable for high-end cryogenic high-pressure heavy-load working conditions. Can provide low-temperature heat treatment optimization, stress
MOQOur factory's low-temperature steel pipe caps adopt a high-end low-temperature pipe fitting flexible foreign trade minimum order model, suitable for the diverse needs of LNG engineering replacement parts, cryogenic technical transformation, air separation equipment supporting, sample submission for inspection, and batch complete set export. The MOQ for conventional standard specifications is as low as 1 piece, and a single piece can be produced and shipped, with no minimum order threshold, no specification restrictions, and no material restrictions. Market hot-selling WPL6 American standard, 16MnDG
Lead TimeThe factory has established a dedicated heat treatment production line and constant-temperature dust-proof warehouse for low-temperature pipe fittings, and maintains massive stock of mainstream standard low-temperature steel pipe caps in WPL6 and 16MnDG, rapidly responding to urgent construction nodes of global low-temperature energy, chemical, and air separation projects. Conventional DN15–DN600 standard elliptical type, SCH40 conventional wall thickness, WPL6/16MnDG general models in stock
PackagingLow-temperature steel pipe caps adopt high-end special equipment export-grade protective packaging, customized for the high-strength protection standards of precision bevels and low-temperature pressure-bearing pipe fittings, eliminating the impact of transportation collisions, bevel damage, paint wear, and moisture rust on welding and sealing performance. Small-diameter pipe caps are individually film-wrapped and fully wrapped with thickened bubble film for protection, and high-strength hard plastic protective caps are installed on pipe end welding bevels, focusing on protecting precision welding surfaces and sealing areas. Medium-diameter products are fully covered with waterproof and anti-rust stretch film, and corners are reinforced with anti-collision corner protectors, avoiding long-distance transportation bump wear and surface oxidation. Large-diameter low-temperature pipe caps are fixed with fumigated solid wood pallets, reinforced with multi-point flexible steel straps, and sealed and wrapped with double-layer waterproof tarpaulins. The pallets comply with international quarantine standards and can be directly cleared through customs across borders. All products strictly according to material,
Reference PriceInquiry

Applications

  • End closure of LNG liquefied natural gas transmission pipeline networks, LNG filling station terminal plugging, and supporting pipelines of low-temperature storage tanks
  • Pipeline sealing and plugging of low-temperature pipeline networks in air separation units and low-temperature separation units
  • Pipeline terminal sealing for low-temperature coal chemical synthesis units, liquid nitrogen and liquid oxygen process pipelines, and low-temperature distillation systems
  • Sealing for low-temperature gathering and transportation pipeline networks and field transmission pipelines in polar and severe cold oil and gas fields
  • Low-temperature energy storage heat exchange pipelines and refrigeration process closed pipeline network systems
  • Sealing renovation and technical modification supplementary parts for outdoor industrial pipelines in northern extremely cold plant areas and severe cold regions
  • Sealing scenarios requiring non-standard customization, such as renovation of old low-temperature pipeline networks and non-standard pipe opening connection for imported equipment

Procurement & Delivery

Conventional standard specifications have a minimum order quantity of 1 piece; mainstream standard models such as WPL6 and 16MnDG are kept in stock, and can support engineering supplementary parts and urgent construction schedules. Small-diameter pipe caps are individually film-covered and wrapped in bubble wrap, with hard plastic protective covers added to the bevels; medium-diameter ones are wrapped in stretch film and fitted with anti-collision corner protectors; large-diameter ones use fumigated solid wood pallets, steel strip reinforcement, and double-layer waterproof tarpaulins, and the pallets comply with international quarantine standards and can clear customs across borders. Products are stored by category according to material, specification, wall thickness, and standard, with bilingual Chinese-English traceability labels, heat numbers, and inspection numbers affixed. For specific delivery times and freight, please contact us to confirm.

Service & Support

Before sales, we provide low-temperature material selection, temperature resistance grade verification, and pressure condition matching, and assist in confirming the correspondence between materials such as WPL6 and 16MnDG and project standards. During sales, we synchronize forming, heat treatment, flaw detection, pressure testing, and shipping progress, with supporting bilingual acceptance documents, low-temperature inspection reports, and customs clearance documents. After sales, we provide an 18-month international warranty; during the warranty period, cracking, leakage, or low-temperature failure caused by production processes, low-temperature performance, material defects, or dimensional accuracy issues will be remanufactured and reshipped free of charge. Equipped with a team of low-temperature special equipment engineers, we provide remote installation guidance, low-temperature pipeline network commissioning, and troubleshooting.

FAQ

What is the difference between low-temperature steel pipe caps and ordinary carbon steel pipe caps?

Ordinary carbon steel pipe caps do not have low-temperature impact performance and are prone to cold brittleness and cracking in sub-zero environments. Low-temperature steel pipe caps use low-temperature special steels such as WPL6 and 16MnDG, undergo stress relief heat treatment, maintain toughness in a -46°C deep cryogenic environment, and are subjected to low-temperature impact tests before leaving the factory, making them suitable for low-temperature pipeline networks such as LNG, liquid nitrogen, and liquid oxygen.

How to choose between WPL6 and 16MnDG?

WPL6 is an American standard material with a temperature resistance of -46°C, suitable for international LNG projects and foreign-related EPC projects; 16MnDG has a temperature resistance of -40°C, corresponding to domestic low-temperature engineering and the GB system. Specific selection needs to be combined with the project execution standard, design temperature, and medium. You are welcome to contact us for confirmation.

What specifications and connection methods do low-temperature steel pipe caps have?

Covers DN15–DN1200 (NPS1/2–NPS48), wall thicknesses from SCH20 to XXS, pressure ratings PN10–PN160, Class150–Class900. Connection forms include butt welding, socket welding, and threaded NPT/BSP. Structures include 2:1 elliptical, hemispherical, spherical cap, and flat bottom types.

Can you customize non-standard sizes or ultra-low-temperature processes?

Yes. We support customization of non-standard overall height, special curvature, special bevels, thickened pressure-bearing, and special-shaped flat bottom structures. We can also strengthen ultra-low-temperature impact performance as needed and customize -60°C ultra-deep cryogenic process treatment. Please provide drawings, dimensions, and quantities, and we will assist with verification and quotation.

What inspection documents are included with the factory shipment?

Each batch is accompanied by a low-temperature impact report, a flaw detection report, a material MTC certificate, and a certificate of conformity, and bilingual Chinese-English acceptance documents and customs clearance documents can be provided according to project requirements.

How are the minimum order quantity and delivery time arranged?

Conventional standard specifications have a minimum order quantity of 1 piece, and mainstream models of WPL6 and 16MnDG are in stock, which can accommodate project supplement parts and urgent construction schedules. For the specific delivery time of non-standard custom products and extra-large diameter products, please contact us to confirm.

Submit Inquiry

Please fill in the following information, and we will contact you as soon as possible to provide product solutions or quotes based on your needs.