Pitting & Crevice Corrosion. Grinding debris from work carried above a tube run that has initiated Pitting Corrosion on Duplex material..

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2 Pitting Corrosion

3 Pitting & Crevice Corrosion Grinding debris from work carried above a tube run that has initiated Pitting Corrosion on Duplex material..

4 Pitting & Crevice Corrosion Note the Crevice Corrosion on this 2507 material at the back of the fitting & on the tube.

5 Crevice Corrosion Under Clamps

6 Pitting & Crevice Corrosion 316 Metal on metal not a good idea. Note the 2 points of Crevice Corrosion where the clamp makes contact with the tube

7 316 Stainless Steel Time to Failure 316 Stainless tube failed after 2 years on a new Tug Boat Malcolm Parratt, New Build Superintendent, Swire Offshore. The 316 Stainless Steel tube failed on the Bonga FPSO after 18 months in service Yemi Okeremi, Senior corrosion Engineer at Shell.

8 316 Stainless Steel Time to Failure In the past 3 years alone, dozens of in-service tubing failures in small-bore 316L SS tubing have been reported on most BPoperated GoM deep-water installations. The vast majority of these incidents are attributed to external corrosion, the cause of which is due to the susceptibility of 300-series austenitic stainless steels to crevice and pitting corrosion in marine atmospheric environments. Other BP locations (e.g., North Sea, Trinidad), major oil and gas producers, and other sectors such as the NASA and the military have had similar historical and recent experience with chronic external corrosion of Type 316L SS tubing. This problem not only results in service disruptions and increasingly expensive maintenance and repair, but poses potentially significant risks to health, safety, and the environment if not effectively mitigated and/or prevented. Ardjan Kopliku BP Corrosion Lead -GoM

9 Pitting & Crevice Corrosion Super Duplex Alloys Crevice Corrosion on 2507 tubing accelerated by the 316 clamp fingers separating the tube.

10 Crevice Corrosion Crevice Corrosion on 316 St.Steel under the clamps. Despite more than 10 years marine exposure on a Shell semi submersible support vessel the exposed surface of a section of Tungum Alloy Tube remains clear of corrosion. The Stainless steel Section from a Southern North Sea gas platform in the Leman field shows crevice corrosion after barely 4 years in the same environment.

11 Total Lifetime Capital Cost - 30 Years Project Based Instrumentation Cost Comparison Sheet Reason - Concerns about differences in total material tube and fitting combination costs Notes: Prices shown are in $ USD and are based on the quantity of Tungum tube supplied on a 2015 project Tube Size and Wall thickness Quantity in Ft. Tungum tube and 316 fittings Tungum tube and Triplelok Brass fittings 316 tube and fittings 6MO tube and fittings 2507 tube and fittings 625 tube and fittings C276 tube and fittings.250"od x.065" 40 $353 $328 $123 $538 $940 $1,008 $ "od x.083" 147,592 $1,512,365 $1,331,233 $1,202,422 $2,896,919 $4,677,597 $9,341,364 $9,102, "od x.109" 930 $29,266 $26,752 $11,977 $43,892 $69,613 $98,617 $132, "od x.134" 49,282 $1,328,798 $1,055,307 $1,110,479 $2,698,912 $5,076,157 $6,882,351 $11,141,531 TOTAL $2,870,783 $2,413,620 $2,325,001 $5,640,262 $9,824,307 $16,323,341 $20,377,391 INITIAL SAVINGS USING TUNGUM TUBE AND 316 FITTINGS -$545,782 $2,769,479 $6,953,524 $13,452,558 $17,506,608 PREDICTED TIME TO FAILURE 30 YEARS PLUS 30 YEARS PLUS 4 YEARS 20 YEARS 20 YEARS 30 YEARS 30 YEARS

12 Oil & Gas- HP control lines <5,000 psi Tungum tube runs (gold colour) showing standard working practices for clamping & bend radius s

13 Oil & Gas- Safety Shut Down Conduit Tungum tube runs used as a corrosion resisting conduit for wire rope 90 Pulleys

14 Oil & Gas- Clamping Arrangements Tungum tube runs (gold colour) showing standard working practices for using St.Steel twin ferule fittings & 3x Dia. bend radius s. However, not a good idea to have 2 tube runs tight side by side. Leave a 5mm minimum gap where possible.

15 Oil & Gas- HP Lines Twin Ferrule Fittings Tungum tube runs (gold colour) showing standard working practices for using St.Steel twin ferule fittings & 3x Dia. bend radius s

16 Dive Systems Tungum for O₂ Service

17 Oxygen Compatible Systems Hyperbaric Chamber

18 Military Fighting Vehicles, Hydraulic Lines

19 Transport Brake Line Systems

20 Typical End Users & Specifiers

21 Tungum Protective Oxide Layer Tungum s protective oxide layer polished back to reveal that no crevice corrosion has occurred under the pipe clamp.

22 Tungum Protective Oxide Layer Tungum tube used for Temperature Safety Element (TSE) loops in service for 15 years. Note the green verdigris oxide layer, on the tube. This is to be expected after this period of time and is part of the tubes protective system.

23 Tungum Protective Oxide Layer Tungum tube showing the green verdigris oxide layer after 15 years in service with no galvanic corrosion issues with the St.Steel fittings into the bulkhead.

24 Applications in Oil & Gas Non-Process Hydraulic lines <5,000 psi Pneumatic lines <5,000 psi TSE Loops Sea Water Flow rate < 4-5 mtr per/sec Pressure sensing lines Potable water lines Grey & black water Chemical injection lines Caution, solution compatibility Diesel / fuel lines Oxygen lines Conduit tubing- Emergency shut down systems Important note Avoid applications with Acetylene Ammonia & Mercury

25 Key benefits Excellent lifetime cost compared to other tubing options No recorded failures of Tungum tube when correctly used and installed Compatible and approved with all industry recognised tube fittings Quicker installation times - can be as little as 75% of the time compared to Super Duplex or Austenitic St.Steels Reduced system down times due to its longer life Material of choice for Oxygen and hyperbaric systems Over 30 years of experience of real time Oil & Gas applications

26 Specifications ASTM B Temper TF00 Seamless Copper Alloy (UNS No. C69100) Pipe and Tube BS EN CW700R-R430 Copper and Copper Alloys-Seamless, Round Tubes for General Purposes ASTM G Determining the Combustion Behavior of Metallic Materials in Oxygen-Enriched Atmospheres ASME B31.1 and B31.3 USCG United States Coast Guard NORSOK M-650 Identified as ALLOY CZ127 In-house specification TCL100 Ministry of Defence specifications: Aviation: DTD5019 (for high pressure systems) DTD253A (for low pressure systems) Navy: NES749 part 3 Army: AFS4000

27 ISO9001:2008 Approval

28 Chemical Composition Element Min % Max% Copper Aluminium Nickel Silicon Iron 0.25 Lead 0.05 Tin 0.10 Manganese 0.10 Total Other 0.50 Zinc The Remainder

29 Physical Properties Mean Ultimate Tensile Strength 480 N/mm² (31.07 tons per Sq. in.) Mean 0.2% Proof Stress 240 N/mm² (15.54 tons per Sq. in.) Design Stress at 4:1 Safety Factor N/mm² (6.96 tons per Sq. in.) Hardness 140 HV5 max. Elongation (Average) 45 Per Cent Magnetic Permeability µ Max. Thermal Conductivity at 300 K 1.0W/cm K. Weight 8.52 x 10 kg/mm³ (0.308 lbs per cu.in.)

30 Typical material test cert

31 Tungum Limited Family owned UK Limited Company Established in 1933 World wide distributor network World wide approvals and certifications