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Butyl rubber O-ring seals: Revision of test procedures for stockpile materials

Description: Extensive testing showed little correlation between test slab and O-ring performance. New procedures, comparable to those used with the traditional test slabs, were defined for hardness, compression set, and tensile property testing on sacrificial O-ring specimens. Changes in target performance values were made as needed and were, in one case, tightened to reflect the O-ring performance data. An additional study was carried out on O-ring and slab performance vs cure cycle and showed little sensitivity of material performance to large changes in curing time. Aging and spectra of certain materials indicated that two sets of test slabs from current vendor were accidently made from EPDM rather than butyl rubber. Random testing found no O-rings made from EPDM. As a result, and additional spectroscope test will be added to the product acceptance procedures to verify the type of rubber compound used.
Date: December 1, 1996
Creator: Domeier, L.A. & Wagter, K.R.
Partner: UNT Libraries Government Documents Department

TESTING OF TMR SAND MANTIS FINAL REPORT

Description: Screening tests of Sand Mantis candidate materials selected for erosion resistance have been completed. The results of this testing identified that over a relatively short period of operation (<1 hour), measurable erosion will occur in each of the candidate zoom tube materials given equal operating exposure. Additionally, this testing has shown that erosion of the rubber discharge hose directly downstream of the vehicle could be expected to limit the service life of the discharge hose. On the basis of these test results, SRNL recommends the following; {lg_bullet} redesign of critical system components (e.g., zoom tube, discharge hose) should be conducted to improve system characteristics relative to erosion and capitalize on the results of this testing, {lg_bullet} continued efforts to deploy the Sand Mantis should include testing to better define and optimize operating parameters, and gain an understanding of system dynamics, {lg_bullet} discontinue wear testing with the selected materials pending redesign of critical system components (1st recommendation) and inclusion of other candidate materials. The final selection of additional candidate materials should be made following design changes, but might include a Stellite alloy or zirconia.
Date: June 12, 2007
Creator: Krementz, D & William Daugherty, W
Partner: UNT Libraries Government Documents Department

On the response of rubbers at high strain rates.

Description: In this report, we examine the propagation of tensile waves of finite deformation in rubbers through experiments and analysis. Attention is focused on the propagation of one-dimensional dispersive and shock waves in strips of latex and nitrile rubber. Tensile wave propagation experiments were conducted at high strain-rates by holding one end fixed and displacing the other end at a constant velocity. A high-speed video camera was used to monitor the motion and to determine the evolution of strain and particle velocity in the rubber strips. Analysis of the response through the theory of finite waves and quantitative matching between the experimental observations and analytical predictions was used to determine an appropriate instantaneous elastic response for the rubbers. This analysis also yields the tensile shock adiabat for rubber. Dispersive waves as well as shock waves are also observed in free-retraction experiments; these are used to quantify hysteretic effects in rubber.
Date: February 1, 2010
Creator: Niemczura, Johnathan Greenberg (University of Texas-Austin)
Partner: UNT Libraries Government Documents Department

Evaluation of the residue from microset on various metal surfaces.

Description: Fast-curing impression materials are sometimes used to cast negative-mold replications of physical defects on material surfaces. The negative-mold impressions can then be used for further measurements to record the nature of the defect. These impression materials have been designed to cure quickly, and with very low adhesion, so that they can be easily removed from the surface leaving little residual contamination. Unfortunately, some contaminant is retained by the substrate material. This investigation seeks to identify the composition and quantity of the remaining material upon removal of Microset Synthetic Rubber Replicating Compound from several material surfaces. Coe-Flex was used as a relative comparison to Microset. On fifteen different substrate materials the Microset leaves no visible trace of contaminant, however, X-ray photoelectron spectroscopy shows evidence of a thin silicone-based contaminant film of approximately 2 nm thickness.
Date: April 1, 2011
Creator: Brumbach, Michael Todd
Partner: UNT Libraries Government Documents Department

EVALUATION OF GLOVEBOX GLOVES FOR EFFECTIVE PERMEATION CONTROL

Description: A research and development task was undertaken to determine the permeabilities of hydrogen and dry air through different polymeric glove materials that are used to maintain the integrity of glovebox secondary containment. Fifteen different glove samples were obtained from four different manufacturers and samples cut from these gloves were tested. The gloves included baseline butyl rubber, Viton{reg_sign}, Dupont{reg_sign} Hypalon{reg_sign}, polyurethane, as well as composite gloves. The testing indicated that all of the vendor's butyl rubber gloves and the Jung Viton{reg_sign} gloves performed comparably in both gases.
Date: February 29, 2012
Creator: Korinko, P.
Partner: UNT Libraries Government Documents Department

Drop Simulation of 6M Drum with Locking-Ring Closure and Liquid Contents

Description: This paper presents the dynamic simulation of the 6M drum with a locking-ring type closure subjected to a 4.9-foot drop. The drum is filled with water to 98 percent of overflow capacity. A three dimensional finite-element model consisting of metallic, liquid and rubber gasket components is used in the simulation. The water is represented by a hydrodynamic material model in which the material's volume strength is determined by an equation of state. The explicit numerical method based on the theory of wave propagation is used to determine the combined structural response to the torque load for tightening the locking-ring closure and to the impact load due to the drop.
Date: April 17, 2006
Creator: Wu, T
Partner: UNT Libraries Government Documents Department

Modeling Emissions of Volatile Organic Compounds from New Carpets

Description: A simple model is proposed to account for observed emissions of volatile organic compounds (VOCs) from new carpets. The model assumes that the VOCs originate predominantly in a uniform slab of polymer backing material. Parameters for the model (the initial concentration of a VOC in the polymer, a diffusion coefficient and an equilibrium polymer/air partition coefficient) are obtained from experimental data produced by a previous chamber study. The diffusion coefficients generally decrease as the molecular weight of the VOCs increase, while the polymer/air partition coefficients generally increase as the vapor pressure of the compounds decrease. In addition, for two of the study carpets that have a styrene-butadiene rubber (SBR) backing, the diffusion and partition coefficients are similar to independently reported values for SBR. The results suggest that predictions of VOCs emissions from new carpets may be possible based solely on a knowledge of the physical properties of the relevant compounds and the carpet backing material. However, a more rigorous validation of the model is desirable.
Date: February 1, 1993
Creator: Little, J.C.; Hodgson, A.T. & Gadgil, A.J.
Partner: UNT Libraries Government Documents Department

Interactions of Jet Fuels with Nitrile O-Rings: Petroleum-Derived versus Synthetic Fuels

Description: A transition from petroleum-derived jet fuels to blends with Fischer-Tropsch (F-T) fuels, and ultimately fully synthetic hydro-isomerized F-T fuels has raised concern about the fate of plasticizers in nitrile-butadiene rubber o-rings that are contacted by the fuels as this transition occurs. The partitioning of plasticizers and fuel molecules between nitrile o-rings and petroleum-derived, synthetic, and additized-synthetic jet fuels has been measured. Thermal desorption of o-rings soaked in the various jet fuels followed by gas chromatographic analysis with a mass spectrometric detector showed many of the plasticizer and stabilizer compounds were removed from the o-rings regardless of the contact fuel. Fuel molecules were observed to migrate into the o-rings for the petroleum-derived fuel as did both the fuel and additive for a synthetic F-T jet fuel additized with benzyl alcohol, but less for the unadditized synthetic fuel. The specific compounds or classes of compounds involved in the partitioning were identified and a semiquantitative comparison of relative partitioning of the compounds of interest was made. The results provide another step forward in improving the confidence level of using additized, fuIly synthetic jet fuel in the place of petroleum-derived fueL
Date: January 1, 2008
Creator: Gormley, R.J.; Link, D.D.; Baltrus, J.P. & Zandhuis, P.H.
Partner: UNT Libraries Government Documents Department

Interactions of Jet Fuels with Nitrile O-Rings: Petroleum-Derived versus Synthetic Fuels

Description: A transition from petroleum~derived jet fuels to blends with Fischer-Tropsch (F~T) fuels, and ultimately fully synthetic hydro-isomerized F-T fuels has raised concern about the fate of plasticizers in nitrile-butadiene rubber a-rings that are contacted by the fuels as this transition occurs. The partitioning of plasticizers and fuel molecules between nitrile a-rings and petroleum-derived, synthetic, and additized-synthetic jet fuels has been measured. Thermal desorption of o-rings soaked in the various jet fuels followed by gas chromatographic analysis with a mass spectrometric detector showed many of the plasticizer and stabilizer compounds were removed from the o-rings regardless of the contact fuel. Fuel molecules were observed to migrate into the o-rings for the petroleum-derived fuel as did both the fuel and additive for a synthetic F-T jet fuel additized with benzyl alcohol, but less for the unadditized synthetic fuel. The specific compounds or classes of compounds involved in the partitioning were identified and a semiquantitative comparison of relative partitioning of the compounds of interest was made. The results provide another step forward in improving the confidence level of using additized, fully synthetic jet fuel in the place of petroleum-derived fuel.
Date: January 1, 2009
Creator: Gormley, R.J.; Link, D.D.; Baltrus, J.P. & Zandhuis, P.H.
Partner: UNT Libraries Government Documents Department

Phase reference materials for photoacoustic spectroscopy

Description: Interest in the phase of photoacoustic signals has increased greatly since the advent of phase modulation in FTIR spectroscopy. The photoacoustic phase provides information on the depth of the light-absorbing species within a solid sample. A spectroscopist needs data from a phase-reference material for standardizing phase measurements and for correcting the instrumental effects on the observed phase. Unfortunately, there is no universally accepted phase-reference material. The authors have studied the photoacoustic-signal phase and magnitude behavior for several potential phase-reference materials as a function of experimental parameters, such as beam modulation frequency, sample position in the photoacoustic cell, and cell purge gas. Theoretically, an ideal surface-absorbing material would have a photoacoustic phase that trails the phase of the excitation light by 90{degree}. They have found no material with this behavior, although some come close under a limited range of conditions. The three samples were separately sealed in the photoacoustic detector and illuminated by a red LED that was modulated at selected frequencies. The phases of the samples vary rapidly at very low frequencies because of the response of the cell microphone. Above that range, all three are within 10{degree} of the ideal 90{degree}, but each varies linearly with frequency with a different slope. The behaviors of these and other samples will be discussed in detail.
Date: June 1, 1999
Creator: Jones, R.; Bajic, S. & McClelland, J.
Partner: UNT Libraries Government Documents Department

Aluminum: Aluminum Scrap Decoater

Description: NICE3 and the Philip Services Corporation are cost-sharing a demonstration project to decoat metal using indirect-fired controlled-atmosphere (IDEX) kilns, which can both process solid organics such as rubber and plastics, and minimize dust formation and emission of volatile organic compounds. The publication explains how this cost-effective, two-step system operates.
Date: January 29, 1999
Creator: Blazek, S.
Partner: UNT Libraries Government Documents Department

Effects of Tritium in Elastomers

Description: A number of elastomers, used as flange gaskets in the piping system of the Savannah River Plant tritium facilities, are being examined to identify those compounds more radiation-resistant that the currently specified Buna-N rubber and to study the mechanism of tritium radiation damage. This paper discusses this study.
Date: March 4, 2003
Creator: Zapp, P.E.
Partner: UNT Libraries Government Documents Department

The structure of carbon black-elastomer composites by small-angle neutron scattering and the method of contrast variation

Description: We have been exploring the use of small-angle neutron scattering and the method of contrast variation to give a new look at a very old problem: reinforcement of elastomers by carbon black in durable rubber products. Carbon black has a hierarchy of structures consisting of particles covalently bound into aggregates, which in turn associate by weak interactions into agglomerates. We found that in one carbon black, HSA, the aggregates are rodlike, containing an average of 4-6 particles. The aggregates have an outer graphitic shell and an inner core of lower density carbon. The core is continuous throughout the carbon black aggregate. Contrast variation of swollen HSA-polyisoprene gels shows that the HSA is completely embedded in polyisoprene and that the agglomerates are formed predominantly by end on associations of the rodlike aggregates. The surface structure of the carbon black appears smooth over length scales above about 10 {angstrom}. Further studies using production carbon blacks suggest that these structural characteristics are generally present in commercial rubber composites.
Date: July 1, 1996
Creator: Hjelm, R.P.; Wampler, W. & Gerspacher, M.
Partner: UNT Libraries Government Documents Department

Nonlinear viscoelastic response of carbon black-filled butyl rubber and implications for o-ring aging

Description: Butyl rubber, unfortunately, has pronounced nonlinear viscoelastic behavior, which may be modelled by a separable KBKZ formalism. While these effects seem to have minimal impact on accelerated sealing force measurements, they do severely impact compression set tests. Therefore, a new test is suggested for evaluating field-return o-rings which is free from such confounding effects.
Date: November 1, 1997
Creator: Adolf, D.
Partner: UNT Libraries Government Documents Department

Fluid flow release regulating device, ERIP {number_sign}624: Final report

Description: DOE/ERIP project {number_sign}624 ``Fluid Flow Release Regulating Device`` designed, constructed, tested, and installed a rubber crest gate for regulating water levels at an impoundment such as a hydroelectric dam. A 92 foot long by 27 inch high rubber panel was installed in January 1997. Initial results were good until fabric degradation internal to the rubber caused loss of stiffness. Substitutes for the failed fabric are being tested. The project will continue after DOE participation terminates.
Date: December 1, 1997
Partner: UNT Libraries Government Documents Department

Surface analysis of rubbers and plastics using secondary neutral mass spectrometry.

Description: Rubber and plastics are complex mixtures of long-chain polymers, smaller organic additives used as plasticizers, mildicides, fungicides, colorants, etc., and inorganic additives such as carbon and silica. Surface analysis of such materials is at once difficult and important. The difficulty lies in the need to identify specific carbon molecules on a very similar organic surface. The importance arises from the dramatic effect that the distribution and concentration of additives have on the physical properties of polymeric materials. Recently we have had some success in applying laser desorption post-ionization mass spectrometry in measuring the surface concentration and distribution of both additives and the polymer molecules themselves. The key has been to use the photoionization properties of the analyte of interest to augment mass spectrometric information.
Date: August 23, 1999
Creator: Pellin, M. J. & Savina, M. R.
Partner: UNT Libraries Government Documents Department

Enhanced Stuffing Box Rubbers Test Report

Description: The Rocky Mountain Oilfield Testing Center (RMOTC) and Scott's Oil Field Service tested an enhanced stuffing box rubber at the Naval Petroleum Reserve No. 3. The enhanced stuffing box rubbers have saved money from not having to replace packing as often and not spilling valuable oil on the ground. A reduction in environmental hazards and the cost of cleaning up spilled oil have also been a benefit.
Date: July 1, 2002
Creator: Rochelle, J.
Partner: UNT Libraries Government Documents Department

Prompt non-tire rubber recycling : final report for phases 1 and 2.

Description: This report summarizes an assessment conducted by Environmental Technologies Alternatives, Inc., under a subcontract to Argonne National Laboratory. The project was conducted in two phases. An assessment of alternative technologies for recycling of prompt non-tire rubber was conducted in the first phase, and an experimental program focusing on a new technology called the catalytic Regeneration Process offered the greatest opportunity for recovery of high-value recyclable rubber material. An experimental and large-scale test program was undertaken to further delineate the economic potential as an essential step leading to commercial deployment and to determine the course of continued development of the technology by the private sector. The experimental program defined process-operating conditions for the technology and verified the degree of devulcanisation achievable for two rubber compounds: ethylene-propylene-nonconjugated-diene monomer (EPDM) and neoprene. To determine product acceptance, samples of devulcanized EPDM and neoprene were prepared and used in factory trials for the production of automotive moldings (EPDM) and fiber-filled belting (neoprene). The factory trials indicated that the physical properties of the products were acceptable in both cases. The appearance of molded and calendared surface finishes was acceptable, while that of extruded finishes was unsatisfactory. The fiber-filled neoprene belting application offers the greatest economic potential. Process costs were estimated at $0.34/lb for neoprene waste rubber relative to a value of $0.57/lb. The results of the experimental program led to the decision to continue development of this technology is being planned, subject to the availability of about $3 million in financing from private-sector investors. The ability to recycle non-tire rubber scrap could conserve as much as 90,000 Btu/lb, thus yielding an estimated energy savings potential of about 0.25 quad/yr.
Date: June 25, 1999
Creator: Smith, F. G. & Daniels, E. J.
Partner: UNT Libraries Government Documents Department

Explanation of Significant Difference (ESD) for the A-Area Burning/Rubble Pits (731-A/1A) and Rubble Pit (731-2A) (U)

Description: The A-Area Burning/Rubble Pits (731-A/1A) and Rubble Pit (731-2A) (ABRP) operable unit (OU) is located in the northwest portion of Savannah River Site (SRS), approximately 2.4 kilometers (1.5 miles) south of the A/M Area operations. Between 1951 and 1973, Pits 731-A and 731-1A were used to burn paper, plastics, wood, rubber, rags, cardboard, oil, degreasers, and solvents. Combustible materials were burned monthly. After burning was discontinued in 1973, Pits 731-A and 731-1A were also converted to rubble pits and used to dispose of concrete rubble, bricks, tile, asphalt, plastics, metal, wood products, and rubber until about 1978. When the pits were filled to capacity, there were covered with compacted clay-rich native soils and vegetation was established. Pit 731-2A was only used as a rubble pit until 1983 after which the area was backfilled and seeded. Two other potential source areas within the OU were investigated and found to be clean. The water table aquifer (M-Area aquifer) was also investigated.
Date: November 17, 2000
Creator: Morgan, Randall
Partner: UNT Libraries Government Documents Department

CHARACTERIZATION OF TENSILE STRENGTH OF GLOVEBOX GLOVES

Description: A task was undertaken to compare various properties of different glovebox gloves, having various compositions, for use in gloveboxes at the Savannah River Site (SRS). One aspect of this project was to determine the tensile strength (TS) of the gloves. Longitudinal tensile samples were cut from 15 different gloves and tensile tested. The stress, load, and elongation at failure were determined. All of the gloves that are approved for glovebox use and listed in the glovebox procurement specification met the tensile and elongation requirements. The Viton{reg_sign} compound gloves are not listed in the specification, but exhibited lower tensile strengths than permissible based on the Butyl rubber requirements. Piercan Polyurethane gloves were the thinnest samples and exhibited the highest tensile strength of the materials tested.
Date: February 29, 2012
Creator: Korinko, P. & Chapman, G.
Partner: UNT Libraries Government Documents Department

Crystallization Behavior of Virgin TR-55 Silicone Rubber Measured Using Dynamic Mechanical Thermal Analysis with Liquid Nitrogen Cooling

Description: Dynamic mechanical thermal analysis (DMTA) of virgin TR-55 silicone rubber specimens was conducted. Two dynamic temperature sweep tests, 25 to -100 C and 25 to -70 to 0 C (ramp rate = 1 C/min), were conducted at a frequency of 6.28 rad/s (1 Hz) using a torsion rectangular test geometry. A strain of 0.1% was used, which was near the upper limit of the linear viscoelastic region of the material based on an initial dynamic strain sweep test. Storage (G{prime}) and loss (G{double_prime}) moduli, the ratio G{double_prime}/G{prime} (tan {delta}), and the coefficient of linear thermal expansion ({alpha}) were determined as a function of temperature. Crystallization occurred between -40 and -60 C, with G{prime} increasing from {approx}6 x 10{sup 6} to {approx}4 x 10{sup 8} Pa. The value of {alpha} was fairly constant before ({approx}4 x 10{sup -4} mm/mm- C) and after ({approx}3 x 10{sup -4} mm/mm- C) the transition, and peaked during the transition ({approx}3 x 10{sup -3} mm/mm- C). Melting occurred around -30 C upon heating.
Date: February 11, 2010
Creator: Small IV, W & Wilson, T S
Partner: UNT Libraries Government Documents Department