Bright Anealed Coiled Steel Tubing Metallic Bright Surface For Downhole

Standards and Specifications

Alloy 625 Tubing with Enhanced Properties

ASTM B704, Standard Specification for Welded UNS N06625, UNS N06219, and UNS N08825 Alloy Tubes, except in the as-cold worked condition

ASTM B444, Standard Specification for Alloy UNS N06625 Seamless Pipe And Tube

Meets the material limits for annealed and cold-worked, solid solution, nickel-based alloys listed in ISO 15156-3 for material type 4d in Table A.14.

Coiled Tubing Size

Tubing length up to 32,808 feet (10,000 m)

For control line, chemical injection line, umbilicals

Meilong is a supplier of welded and redrawn, seamless and redrawn coiled tubing which are made from corrosion-resistant austenitic, duplex, super duplex stainless steels and nickel alloy grades. We have been specializing in manufacturing coiled tubing used in the oil and gas industry.

Tubing for Control Lines

A direct hydraulic control umbilical provides direct hydraulic control of each valve on a subsea christmas tree, through a bundle of tubes from the topsides hydraulic power unit (HPU) to the subsea tree. No electrical power or signal is required. Actuation of valves is by the supply of hydraulic power to the relevant tube. This is accomplished by opening the relevant valve on the manifold located on the topsided HPU. This type of umbilical is limited to subsea production systems with short offsets to the host and few trees.

Thanks to the experience and expertise gained in the production and inspection, the tubes supplied by Meilong fully meet stringent quality requirements of the oil & gas industries. The tubing deployed in the umbilicals used in aggressive subsea and downhole conditions.

Tubing for Chemical Injection

One of the main challenges in the upstream processes of the oil and gas industry is to protect pipeline and process equipment against waxes, scaling and asphalthane deposits. The engineering disciplines involved in flow assurance play an essential part in mapping the requirements that reduce or prevent loss of production due to pipeline or process equipment blockage. Steel tubing from Meilong is applied to umbilicals and chemical injection systems play an effective role in chemical storage and delivery at an optimizing flow assurance.

Our tubing is characterized with integrity and quality to be specially used in subsea conditions in the industries of oil and gas extraction.

Inconel Alloy 625, Chemical composition

Application: Nickel alloy with very good resistance to pitting, crevice corrosion & sour well environments.

Tensile strength, min.: 120000psi (827MPa)

Yield strength, min.: 60000psi (414MPa)

Elongation in 2 in., min.: 30%

Application

Inconel Alloy 625 seam welded pressure tubing in the heat treated and cold worked condition is typically used in oil and gas wells for chemical injection applications. In such applications, it is commonly referred to as capillary tubing and is free hanging (self-supporting) inside the production casing. The chemicals being injected are often used to enhance production flow rates, inhibit corrosion or scaling and/or de-water. The tubing is frequently supplied as 5,000 to 35,000 ft. coils on a wooden reel, depending on size.

Description

Inconel Alloy 625 is an austenitic nickel / chromium / molybdenum / niobium alloy (see Table 1 on reverse). The high alloy content enables alloy 625 to withstand severe aqueous corrosion environments. High molybdenum content (8.0 to 10.0%) makes the alloy very resistant to chloride pitting and crevice corrosion. High nickel content (58.0% min.) provides relative freedom from chloride ion induced stress-corrosion cracking. Alloy 625 has shown excellent corrosion resistance in oil and gas production environments containing hydrogen sulfide, carbon dioxide and chlorides. Consult ISO 15156-3, Table A.14 for the limits regarding material type 4d in hydrogen sulfide containing environments for oil and gas production.

Manufacturing Process and Resultant Properties

Strip splice welds join lengths of cold rolled strip to enable long lengths between orbital welds (greater than 14,500 ft between orbital welds is achievable). The strip is formed into a tubular cross section and longitudinally seam welded using the gas tungsten arc (GTAW) process. The tubing is first sunk to an intermediate outside diameter, heat treated, and make the same process to obtain the desired size.

Nondestructive Testing (NDT)

Eddy current testing (ECT) is performed on the longitudinally seamwelded tubing and strip splice welds at intermediate size in the as-heat treated condition. Those strip splice welds detected by ECT at intermediate size in the as-heat treated condition. Yield pressure hydrostatic testing is performed on the heat treated tubing at final size.

Quality Assurance

Eddy current test (ECT)

Ultrasonic test

Hydrostatic test

Chemical composition analysis

Tensile test

Hardness test

Dimension & visual inspect

Metallographic analysis

Available materials

Austenitic: 316L

Duplex: S31803, S32205

Super Duplex: S32750

Nickel alloy: N06625, N08825

Norm Equivalence