Abstract: Abrasive discs with spaced portions removed from the circumference in the form of rounded and elongated V-shapes provide, when in use, complete vision of a workpiece being abraded with reduced tendency to snag on obstructions.

Abstract: Bonded abrasive products comprising alumina-based abrasive grains and a geopolymer bond system are significantly improved by providing the grain with a vitreous coating before incorporation in the geopolymer bond.

Abstract: This invention provides an improved backup pad for an abrasive disk adapted to permit a view of surface as it is being ground which comprises a compressible pad and a relatively rigid support member laminated to the pad that has shorter radial dimensions than the pad in those portions of the circumference of the pad that are likely to snag an angled surface during grinding. The result is that abrasive disks borne on the pad are less likely to tear from such contact.

Abstract: The subject of the invention is a mineral wool composition capable of dissolving in a physiological medium which comprises the constituents below, having to the following percentages by weight:______________________________________ (CaO + MgO + BaO + Na.sub.2 O + K.sub.2 O + B.sub.2 O.sub.3) > 30* 2 .times. Al.sub.2 O.sub.3 RO 13.5 to 19.5% R.sub.2 O 14.2 to 23% RO/R.sub.2 O 0.70 to 0.95 CaO/MgO > 1.5 SiO.sub.2 47 to 58.5% Al.sub.2 O.sub.3 0 to 3.5% B.sub.2 O.sub.3 5 to 10% Fe.sub.2 O.sub.3 (total iron) 0 to 3.0% ______________________________________where:RO means oxides of the elements from column 2a of the Periodic Table, including CaO, MgO, BaO and SrO; and R.sub.2 O means oxides from column 1a of the Periodic Table, including Na.sub.2 O, K.sub.2 O and Li.sub.2 O.

Abstract: Shaped ceramic articles can be obtained by screen printing the desired shapes from a dimensionally stable dispersion of a precursor of the ceramic onto a surface, drying the screen printed shapes so obtained and firing them to generate the shaped ceramic articles.

Abstract: Nano-sized powders of alpha alumina can be obtained from a boehmite gel doped with a barrier-forming material such as silica that is then dried, fired and comminuted to powder form.

Abstract: Abrasive tools, such as coated abrasives, made using radaition curable resin binders can be given a greater depth of cure of the binder if they include an acylphosphine oxide initiator.

Abstract: A coated abrasive material comprising a substrate and maker coat and adhered by means of the maker coat a plurality of abrasive grits in the form of U-shaped particles or coils.

Abstract: Cryogenic sedimentation is effective to bring about the rapid separation of sub-micron particles from powder mixtures containing such particles without leading to significant agglomeration.

Abstract: A packing element with a plurality of symmetrically disposed subdivisions within a cylindrical body member provides a very strong, high temperature and corrosive media resistant structure with a large surface area. The elements are of great utility as dumped packing elements in mass transfer applications.

Abstract: Accessories for an angle grinder include a disposable rotary sanding disk having quite large shaped ventilating/viewing apertures, for use with a resilient backing plate also having shaped ventilating apertures. The apertures of one or both parts are shaped so that snagging of the apertures on projections from the work surface is minimized and to facilitate air flow across the work surface during use. This air flow helps in cooling the work and ejecting detritus, so minimizing clogging effects. The ventilating apertures also facilitate viewing the work to be sanded through the spinning disk during the abrasion process, so that operator feedback is immediate. The holes also give the sanding disk more resilience so that a greater area comes in contact with the work and the disk wears more evenly over its abrasive surface.

Abstract: Abrasive discs for use with orbital sanders having dust extractor systems are provided in which the discs are adapted for use with orbital sanders having different patterns and numbers of dust extractor holes.

Abstract: An optical polishing slurry with alumina and ceria components is found to produce an improved polishing performance over either component used alone.

Abstract: The present invention furnishes a device for fiberizing molten mineral materials in order to produce mineral fiber products by means of a spinner (2) having a multiplicity of orifices (6; 8) provided in the peripheral wall (4) thereof, for centrifuging molten mineral materials (10; 12) supplied to the spinner (2), with the spinner (2) comprising on the inside (14) of the peripheral wall (4) compartments (18; 20) arranged in sections and delimited by baffles (16) for separately feeding and separately receiving a respective molten material (10; 12) to at least one associated orifice (6; 8), with the orifices (6; 8) extending at least approximately in a radial direction through the peripheral wall (4). In the present invention a method for producing this device is moreover proposed.

Abstract: A coated abrasive comprising maker and size coats with improved color stability is obtained by the use of a bisphenol/formaldehyde resin binder in either the maker or, more preferably, the size coat.

Abstract: The invention relates to a material based on inorganic fibres at least a proportion of which are multicomponent fibres and the cohesion and/or the geometry of which is (are) ensured, at least partially, by a sizing.It also relates to the use of this material for thermal and/or acoustic insulation.

Abstract: The invention relates to "two-component" inorganic fibers obtained by conjoint fiber formation from two different inorganic compositions, especially two glass compositions based on SiO.sub.2, alkali metal oxides and alkaline-earth metal oxides;the two inorganic compositions have thermal expansion coefficients .alpha. exhibiting a difference .DELTA..alpha. of at least 20.times.10.sup.7 K.sup.-1,they have a minimum viscosity temperature of fiber formation T.sub.log3 of between 830 and 1010.degree. C.,they exhibit a work range of at least 30.degree. C.,each includes, as weight percentages, in all less than 3% of the following compounds: TiO.sub.2, ZnO, BaO and Li.sub.2 O and preferably less than 1% of each of these,they exhibit, as weight percentages, differences in respective contents of boron oxides B.sub.2 O.sub.3 and of sodium oxide Na.sub.2 O such that:(i) .DELTA.B.sub.2 O.sub.3 >2%(ii) .DELTA.Na.sub.2 O>2%.

Abstract: The provision of a fractionating column having fractionating trays designed to ensure that downflowing liquid exiting downcomers does not interfere with vapor passing up through perforations in the trays, ensures that weeping of the liquid through the perforations is avoided without need for an increase in vapor pressure.

Abstract: Accessories for an angle grinder include a rotary disc cutting tool and a rest for supporting the grinder on a surface to be shaped. The rest may be a non-rotating nose beneath the grinder or a rubbing contact mounted on a flat tool, or it may be part of a convex tool. Tilting the grinder about the rest give effective control of the tool. Steeper tilts cause the cutting surface to bite more deeply into the work surface. The grinder is stroked toward the user with the cutting zone trailing. Most disks are perforated. Work to be shaped can be seen through the spinning disk during use.

Abstract: Rapidly releasable attachment of an abrasive disk to a rotary grinder is provided by fitting the disk with a disk retention adapter which clamps onto the disk and is provided with retention means extending from the non-abrasive bearing surface, a also providing a lock-nut assembly for mounting on the drive shaft of the rotary grinder which comprises a number of detents and detent access slots which permit the retention means to be inserted into the slots and, by a simple axial rotation move the retention means into the detents to lock the disk into position.