API MPMS 8.4:2004 pdf download
API MPMS 8.4:2004 pdf download.Manual of Petroleum Measurement Standards Chapter 8—Sampling
Section 4—Standard Practice for Sampling and Handling of Fuels for Volatility Measurement.
7.4. 1 Continuous Sampler, Time Cycle (Noiiproporlional) Type—A sampler designed so that it transfers equal increments of liquid from the pipeline to the sample container at uniform time increments.
7.4.2 Continuous Sampler, Flow – Responsive (Proportional) Type—A sampler designed to automatically adjust the sampling rate to be proportional to the flow rate of the stream.
7.4.3 Calibration—Prior to initial operation, the sample bite size must be verified to be within ±5 % of the specification using an acceptable calibration procedure. Additionally, the required sample volume must be obtained during any sampling period so that the manufacturer’s sampling interval is not exceeded.
7.4.4 Container—The container must be a clean, dry container of convenient size to receive the sample. All connections from the sample probe to the sample container must be free of leaks. The container is constructed in such a manner that it prevents evaporation loss. The construction must allow cleaning. interior inspection, and complete mixing of the sample prior to removal. A fixed volume type container is equipped with a pressure-relief device.
7.5 Grab or Spot Swnpling—Purge approximately three volumes of product through the sample tap and tubing. Divert the sample stream to the sampling container to provide a quantity of sample that will he of sullicient size for analysis.
7.6 Nozzle Sampling—The nozzle sampling procedure is applicable for sampling light fuels from a retail type dispenser.
7.6.1 Apparatus—Sample containers conforming with Section 6 should be used. A spacer, if appropriate, and a nozzle extension as shown in Fig. 8 and Fig. 9 are used when nozzle sampling.
7.6.2 Procedure—Immediately after fuel has been delivered from the pump and the pump has been reset, attach a spacer (Fig. 8), if needed, to the pump nozzle (vapor recovery type). Insert the nozzle extension (Fig. 9) into the previously chilled sample container and insert the pump nozzle into the extension with slot over the air bleed hole. Fill the sample container slowly through the nozzle extension to 70 to 85 % full (Fig. 10). Remove the nozzle extension. Insert the seal and cap or stopper into the sample container at once. Check for leaks. If a leak occurs, discard the sample container and resample. lithe sample container is leak tight. label the container and deliver it to the laboratory.
8. Special Precautions and Instructions
8. 1 Precautions—Vapor pressures are extremely sensitive to evaporation losses and to slight changes in composition. When obtaining, storing, or handling samples. observe the necessary precautions to ensure the samples are representative of the product and satisfactory for Reid equivalent vapor pressure tests. Never manually prepare composite samples for this test. Make certain that containers that are to he shipped by common carrier conform to applicable federal. state, and local regulations. When flushing or purging lines or containers, observe the pertinent regulations and precautions against tire, explosion, and other hazards. Collect all line flushes and bottle rinses for proper recovery or disposal.
8.2 Sample Containers—Use containers of suflicient strength to withstand the pressures to which they can be subjected, and of a type that will permit replacement of the cap or stopper with suitable connections for transferring the sample to the gasoline chamber of the vapor pressure apparatus.
9. Keywords
9.1 dry vapor pressure: fuels; gasoline: gasoline sampling; petroleum products; sampling; sample handling; sampling of volatile products: vapor pressure: volatility.
