ASTM D4860 Standard Test Method for Free Water and Particulate Contamination in Mid-Distillate Fuels (Clear and Bright Numerical Rating)
7. Apparatus
7.1 Micro-Separometer, Mark V Deluxe
7.1.1 The Micro-Separometer is a completely portable and self contained unit capable of operating on an internal rechargeable battery pack or being connected to an a-c power source using power cords that are furnished for various voltages. Connection to an a-c power source provides power to the unit and effects battery recharge. The accessories as well as the expendable materials for six tests can be packed in the cover of the lockable case.
7.1.2 The Micro-Separometer Mark V Deluxe model and the associated control panel is shown in Fig. 1. The emulsifier is on the right side of the raised panel and the syringe drive mechanism is on the left side. The control panel containing the operating controls is mounted on the fixed panel in the left side of the case.
7.1.3 All of the controls are located in a push-button array on the control panel. The push buttons illuminate when depressed, thus, indicating operational status. A circuit breaker located on the control panel provides protection for the a-c power circuit.
7.1.4 By depressing the ON push button, the electronic circuits are energized. The ON push button light pulses on and off when the instrument is being operated by an a-c source and constantly remains on when the battery (d-c) pack is used. The A-G lettered push buttons sequentially illuminate on and off indicating ready operational status.
NOTE 2 - Of the lettered (A-G) push buttons, only the C push button is applicable to this test method.
7.1.5 The RESET push button can be depressed at any time to cancel the test in progress and restore the program to the initial start mode. The lettered push buttons commence to illuminate sequentially, thus indicating a ready operational status enabling test mode selection.
7.1.6 Test mode selection is accomplished by depressing the applicable lettered (C) push button. The depressed push button illuminates and the sequential illumination of the other lettered push buttons ceases. The START push button also illuminates and the syringe drive mechanism moves to the UP position.
7.1.7 The START push button, when depressed sequentially after depressing the C lettered push button, initiates the automatic program for the clear-and-bright test.
7.1.8 The turbidimeter is located under the main control panel and consists of a well in which the sample vial is placed, a light source, and a photocell. A mark on the panel in front of the turbidimeter well is used to align the sample vial.
7.1.9 By depressing the appropriate ARROWED push button, the displayed value on the meter can be increased/decreased, as required, to establish the 100 reference level for the vial of filtered fuel sample in the turbidimeter.
7.2 Accessory equipment and expendable materials needed to perform the test are shown in Fig. 2 and consist of the following:
7.2.1 Syringe Plug, (A) - A plastic plug used to stopper the syringe.
7.2.2 Syringe, (Barrel, B and Plunger, C), a disposable plastic syringe.
7.2.3 Vials, (D) - 25-mm outside diameter vial premarked for proper alignment in the turbidimeter.
7.2.4 Alumicel5 Coalescer/Filter (E), labeled Clear and Bright - an expendable, precalibrated aluminum coalescer/filter cell with a tapered end to fit the syringe.
7.2.5 Wire Aid (F) - A piece of wire with a loop on one end, used to release the air trapped in the barrel of the syringe when the plunger is being inserted. A wire aid is supplied with each Micro-Separometer.
7.2.6 Beaker, catch pan or the plastic container supplied with each Micro-Separometer can be used to receive the waste fuel during the coalescence period of the test (not shown).
7.3 New Syringe, Syringe Plug, Test Sample Vial, and Alumicel Coalescer/Filter are used in each test. These expendable materials are available in a kit containing supplies for six tests. This kit, termed Micro-Separometer Clear and Bright Six Pack, is designed to fit inside the top lid of the Micro-Separometer.
7.4 Sample Container, cylindrical, wide-mouth, clear-glass, container capable of holding at least 900 mL of fuel. The minimum dimensions of the container shall be 100 mm in diameter with a height of 120 mm. The container shall have a lid to seal the contents.
8. Sampling
8.1 Sampling shall be consistent with the procedures of Practice D4057. When practical, take the sample directly into the sample container; however, in some instances the sample can be transferred from the apparatus used to secure the sample to the sample container used in the test.
NOTE 3 - Exercise care when transferring a sample from one container to another to ensure the test sample is representative of the fuel source.
8.2 Use the following procedure when the sample is drawn directly into the sample container from a sampling valve:
8.2.1 Be sure the sampling valve is free of loose solid contaminants. If rust or other loose encrustations are present, remove with a cloth; then flush the sampling valve before taking the actual sample.
8.2.2 Rinse a clean sample container thoroughly with the fuel being sampled.
8.2.3 Draw approximately 700 mL of fuel into the sample container (at least 3/4 full) as rapidly as possible. Use a full flush rather than permitting the fuel sample to trickle out.
8.2.4 A lid must be placed on the container to prevent water absorption or loss from the sample to the ambient environment, especially if the test is performed under different environmental conditions than those of the sample site or at a later time.
