Pipe & Fittings

MEILONG TUBE provides a wide range of tubular product forms and materials mainly for the oil & gas sector. Our products have been successfully used in some of the most aggressive subsea and downhole conditions and we have a long proven track record of supplying products that meet the strict quality requirements of the Oil & Gas and geothermal energy sectors.

Improvements in the technology for the enhanced exploitation of oil and gas fields has increasingly required the use of long continuous lengths of stainless steel and nickel alloy tubulars for hydraulic control, instrumentation, chemical injection, umbilical and flowline control applications. The benefits of this tubular technology have resulted in reduced operating costs, improved recovery methods and reduced capital expenditure by connecting downhole valves and chemical injection with remote and satellite wells to a fixed or floating central operating platform.

Applications
• Downhole hydraulic control lines.
• Downhole c

MEILONG TUBE provides a wide range of capillary tubular product forms and materials mainly for the oil & gas sector. Our products have been successfully used in some of the most aggressive subsea and downhole conditions and we have a long proven track record of supplying products that meet the strict quality requirements of the Oil & Gas and geothermal energy sectors.

Improvements in the technology for the enhanced exploitation of oil and gas fields has increasingly required the use of long continuous lengths of stainless steel and nickel alloy tubulars for hydraulic control, instrumentation, chemical injection, umbilical and flowline control applications. The benefits of this tubular technology have resulted in reduced operating costs, improved recovery methods and reduced capital expenditure by connecting downhole valves and chemical injection with remote and satellite wells to a fixed or floating central operating platform.

Applications of capillary string

• Downhole hydraulic control lines.

• Downhole chemical control lines.

• Subsea control lines for hydraulic power and chemical injection.

• Smoothbore control lines used in fibre optic applications.

Production process

Coiled tubing is available in a range of different product forms depending on the customer requirements. We manufacture seam welded and redrawn, seamless tube products. The standard grades are 316L, alloy 825 and alloy 625. Other grades of stainless steel in duplex and superduplex and nickel alloy are available on request. Tubing can be supplied in the annealed or cold worked condition.

• Seam-welded and redrawn tubing.

• Seamless and redrawn tubing.

Dimensional range of capillary string (coiled tubing)

• Diameter from 3.18mm (0.125’’) to 25.4mm (1.00’’) OD.

• Wall thickness from 0.51mm (0.020’’) to 3mm (0.118”).

• OD tolerance +/- 0.005’’ (0.13mm) and +/- 10% wall thickness. Other tolerances are available on request.

• Coil lengths up to 1500m (5,000ft) without orbital joints depending on product dimensions.

• Coil lengths up to 13,500m (45,000ft) with orbital joints.

• Encapsulated, PVC coated or bare line tubing.

• Available on wooden or steel drums.

Seam-welded & redrawn tubing sizes, imperial

Alloy UNS ASTM OD WT Weight Working pressure

inch inch Lb/ft psi

316L S31603 A269 0.125 0.028 0.030 8,276

316L S31603 A269 0.125 0.035 0.035 10,533

316L S31603 A269 0.250 0.035 0.084 4,949

316L S31603 A269 0.250 0.049 0.110 7,143

316L S31603 A269 0.250 0.065 0.134 9,745

316L S31603 A269 0.375 0.035 0.133 3,182

316L S31603 A269 0.375 0.049 0.178 4,569

316L S31603 A269 0.375 0.065 0.225 6,264

316L S31603 A269 0.375 0.080 0.263 7,878

316L S31603 A269 0.500 0.049 0.246 3,336

316L S31603 A269 0.500 0.065 0.316 4,551

316L S31603 A269 0.500 0.080 0.375 5,729

316L S31603 A269 0.625 0.049 0.315 2,620

316L S31603 A269 0.625 0.065 0.407 3,571

825 N08825 B704 0.125 0.035 0.036 14,749

825 N08825 B704 0.250 0.035 0.086 6,934

825 N08825 B704 0.250 0.049 0.112 10,017

825 N08825 B704 0.250 0.065 0.137 13,652

825 N08825 B704 0.375 0.035 0.136 4,460

825 N08825 B704 0.375 0.049 0.182 6,400

825 N08825 B704 0.375 0.065 0.230 8,775

825 N08825 B704 0.375 0.080 0.270 11,032

825 N08825 B704 0.500 0.049 0.252 4,,678

825 N08825 B704 0.500 0.065 0.323 6,382

825 N08825 B704 0.500 0.080 0.384 8,023

625 N06625 B704 0.250 0.035 0.089 11,920

625 N06625 B704 0.250 0.049 0.116 17,205

625 N06625 B704 0.250 0.065 0.143 23,460

625 N06625 B704 0.375 0.035 0.141 7,660

625 N06625 B704 0.375 0.049 0.189 10,996

625 N06625 B704 0.375 0.065 0.238 15,075

625 N06625 B704 0.375 0.080 0.279 18,954

625 N06625 B704 0.500 0.049 0.261 8,031

625 N06625 B704 0.500 0.065 0.335 10,959

625 N06625 B704 0.500 0.080 0.398 13,779

625 N06625 B704 0.625 0.049 0.333 6,309

The above are tested in the condition of coiled tubing with orbital joints

All joints are X-ray tested

Control line may also be supplied without orbital joints

Certification to EN10204, 3.1

Seam-welded & redrawn tubing sizes, metric

Alloy UNS ASTM OD WT Weight Working pressure

mm mm Kg/m bar

316L S31603 A269 3.18 0.71 0.044 571

316L S31603 A269 3.18 0.89 0.051 726

316L S31603 A269 6.35 0.89 0.121 341

316L S31603 A269 6.35 1.24 0.158 493

316L S31603 A269 6.35 1.65 0.194 672

316L S31603 A269 9.52 0.89 0.192 219

316L S31603 A269 9.52 1.24 0.257 315

316L S31603 A269 9.52 1.65 0.325 432

316L S31603 A269 9.52 2.03 0.380 543

316L S31603 A269 12.7 1.24 0.355 230

316L S31603 A269 12.7 1.65 0.456 314

316L S31603 A269 12.7 2.03 0.542 395

316L S31603 A269 15.88 1.24 0.454 181

316L S31603 A269 15.88 1.65 0.587 246

825 N08825 B704 3.18 0.89 0.052 1,017

825 N08825 B704 6.35 0.89 0.124 478

825 N08825 B704 6.35 1..24 0.162 691

825 N08825 B704 6.35 165 0.198 941

825 N08825 B704 9.52 0.89 0.196 308

825 N08825 B704 9.52 1.24 0.263 441

825 N08825 B704 9.52 1.65 0.332 605

825 N08825 B704 9.52 2.03 0.389 761

825 N08825 B704 12.7 1.24 0.363 323

825 N08825 B704 12.7 1.65 0.466 440

825 N08825 B704 12.7 2.03 0.554 553

625 N06625 B704 6.35 0.89 0.129 822

625 N06625 B704 6.35 1.24 0.168 1,186

625 N06625 B704 6.35 1.65 0.206 1,618

625 N06625 B704 9.52 0.89 0.204 528

625 N06625 B704 9.52 1.24 0.272 758

625 N06625 B704 9.52 1.65 0.344 1,039

625 N06625 B704 9.52 2.03 0.403 1,307

625 N06625 B704 12.7 1.24 0.377 554

625 N06625 B704 12.7 1.65 0.484 756

625 N06625 B704 12.7 2.03 0.572 950

625 N06625 B704 15.88 1.24 0.481 435

The above are tested in the condition of coiled tubing with orbital joints

All joints are X-ray tested

Control line may also be supplied without orbital joints

Certification to EN10204, 3.1

Redrawing process of welded tubes

Long lengths can be made by seam welding formed strip but such tubing has OD & ID discontinuity and may suffer from local problems of mechanical strength or corrosion. A welded & sunk tube improves these aspects and has been proven reliable in service over several decades for offshore applications. Although more expensive than welded only tubing, the welded and redrawn tube is still relatively inexpensive compared to seamless.

Seamless tubing has cross sectional uniformity however, it is the most expensive method of manufacture and has a limitation in the continuous length that can be produced between joints. For a slight premium over the welded & sunk price, tubing can be produced by the welded & floating plug drawn process which results in a product of similar appearance to seamless but with the significant advantage of much longer continuous lengths and greatly reduced costs.

Quality assurance of capillary line

• Eddy current testing

• Hydraulically pressure testing

• Radiographically testing for all orbital joints

• Chemical composition analysis

• Mechanical properties testing

• Visual inspected

capillary string, capillary line, capillary coiled tubing,