ASTM D7095 Standard Test Method for Rapid Determination of Corrosiveness to Copper from Petroleum Products Using a Disposable Copper Foil Strip
5. Apparatus
5.1 Copper Foil Strip Corrosion Test Pressure Vessel, constructed from stainless steel according to the dimensions given in Fig. 1. The vessel shall be capable of withstanding a test pressure of 700 kPa gauge (100 psi). Alternative designs for the vessel's cap and synthetic rubber gasket may be used provided that the internal dimensions of the vessel are the same as those shown in Fig. 1. The internal dimensions of the pressure vessel are such that a nominal 25 mm by 150 mm (1 in. by 6 in.) test tube can be placed inside the pressure vessel.
5.2 Test Tubes, of borosilicate glass with nominal dimensions of 25 mm by 150 mm (1 in. by 6 in.). The internal dimensions shall be checked as acceptable by use of a copper foil strip (see 6.3). When 30 mL of liquid is added to the test tube with the copper foil strip in it, a minimum of 5 mm of liquid shall be above the top surface of the copper foil strip.
5.3 Test Baths:
5.3.1 General - All test baths, whether liquid or solid block, shall be capable of maintaining the test temperature to within +/- 1 °C (2 °F) of the required test temperature, for the entire duration of the test.
5.3.2 Bath(s) Used for Submerging Pressure Vessel(s) - Bath(s) shall be deep enough to submerge one or more pressure vessels (see 5.1) completely during the test. It shall be fitted with suitable supports to hold each pressure vessel in a vertical position when submerged.
5.3.3 Bath(s) Used for Test Tubes - Bath(s) shall be fitted with suitable supports to hold each test tube (see 5.2) in a vertical position to a depth of about 100 mm (4 in.) as measured from the bottom of the test tube to the bath surface. As a liquid bath medium, water and oil have been found satisfactory and controllable at the specified test temperature and duration required by the test procedure. Solid block baths shall meet the test temperature control, test duration, and immersion conditions required by the test procedure, and shall be checked for temperature measurement (heat transfer) for each product class by running tests on tubes filled with 30 mL of product plus a copper foil strip of the given nominal dimensions, plus a temperature sensor.
5.4 Temperature Sensing and Monitoring Device (TSMD), capable of sensing and monitoring the desired test temperature in the bath to within an accuracy of +/- 1 °C (2 °F) or better. The ASTM 12C (12F) (see Specification E1) or IP64C (64F) total immersion thermometer has been found suitable for use in the test. If used, no more than 10 mm (0.4 in.) of the mercury should extend above the surface of the bath at the test temperature.
5.5 Timing Device, electronic or manual, capable of accurately measuring the test duration within the allowable tolerance.
5.6 Forceps, with either stainless steel or polytetrafluoroethylene (PTFE) tips, have been found suitable for use in handling the copper foil strips.
5.7 Optional Equipment:
5.7.1 Polishing Vise, for holding the copper foil strip firmly without marring the edges while polishing. Any convenient type of holder (see X1.2) may be used, provided that the copper foil strip is held tightly and that the surface of the copper foil strip being polished is supported above the surface of the holder.
5.7.2 Viewing Tubes, flat glass test tubes, are convenient for protecting corroded copper foil strips for close inspection or storage (see X1.1 for the description of a flat-glass viewing tube). The viewing tube shall be ofsuch dimensions as to allow the introduction of a copper foil strip (see 6.3) and made of glass free of striae or similar defects.
6. Reagents and Materials
6.1 Wash Solvent - Any volatile, less than 5 mg/kg sulfur hydrocarbon solvent may be used, provided that it shows no tarnish at all when tested for 3 h at 50 °C (122 °F). 2,2,4-trimethylpentane (isooctane) ofminimum 99.75 % purity is the referee solvent and should be used in case of dispute. (Warning - Extremely flammable; see A2.1).
6.2 Surface Preparation/Polishing Materials - Scouring-pad made of polyester material that is free of detergents or spongy material, containing aluminum oxide as a scouring-aid. 3M Scotch Brite 86 (3M No. 05509), approximately 400 grit, green-colored, heavy-duty, hand-pad, has been found suitable for use. Other commercially available 400 grit pads may be used, provided those are also made of polyester material, free of detergents or spongy material, containing aluminum oxide as a scouring-aid.
NOTE 1 - 3M Scotch Brite 86 pads are generally available in the form of 229 mm by 152 mm by 9.5 mm (9 in. by 6 in. by 3/8 in.) thick pads. For ease of handling and polishing, it is recommended that the pads be cut so that the dimensions of the scouring-pads are about 114 mm by 38 mm by 9.5 mm (4 1/2 in. by 1 1/2 in. by 3/8 in.).
6.3 Copper Foil Strips - Use copper foil strips approximately 12.5 mm (1/2 in.) wide, and 0.526 mm to 0.541 mm (0.0207 in. to 0.0213 in.) thick. Cut, straight and smooth, using a sharp tin-snip or any other metal-cutting device approximately 75 mm (3 in.) long strips, from a 30.5 m (100 ft) roll of soft-temper, commercial grade Alloy 110, composed of 99.9 % copper, meeting Specification B152/B152M specifications. Discard copper foil strip after each single use.
6.4 Ashless Filter Paper or Disposable Gloves or Forceps (with either Stainless Steel or Polytetrafluoroethylene (PTFE)) Tips, for use in protecting the copper foil strip from coming in contact with the individual during handling or polishing, or both.
