Abstract: The invention relates to aqueous polymer dispersions comprising at least one polymer obtainable by the reaction of at least one monomer M1 of the general formula (I): H2C?CH—C(O)OR, wherein R is an unbranched alkyl chain comprising from 18 to 22 carbon atoms, and optionally at least one monomer M2. The invention relates moreover to a method for the preparing of such aqueous polymer dispersion and the use thereof as pour point depressant for crude oil, petroleum, and petroleum products.

Abstract: Various methods and devices are provided for use in a walking beam compressor used with an oil well pump. In general, an injectable fibrous sealant is provided for use in a stuffing box to form a seal around a piston rod that couples to a walking beam for pumping oil out of the ground. The injectable fibrous sealant can be configured to form a gas tight seal around the piston rod, while allow reciprocal longitudinal movement of the piston rod therethrough. The injectable fibrous sealant is particularly advantageous as it has an extended life, eliminating the need to replace the seal, and repairs can be performed on-site by injecting additional sealant into the stuffing box.

Abstract: A method is provided for efficiently manufacturing a high quality internal combustion engine piston having an annular cavity allowing for good circulation of cooling fluid. An annular groove is formed at the circumferential edge of the top face of a piston crown, or at the top of the exterior circumferential face of the crown, and an annular protruding strip is formed as a continuation of an edge of the opening of the annular groove. The protruding strip is bent in the direction of the opening of the annular groove by bringing to bear a pressure roller 11, while rotating the main piston body. Consequently, the opening of the annular groove is closed, whereby an annular cavity for circulating cooling fluid is formed so as to surround a pressure receiving recess.

Abstract: The present invention provides a composite magnetic body containing metallic magnetic powder and thermosetting resin and having a packing ratio of the metallic magnetic powder of 65 vol % to 90 vol % and an electrical resistivity of at least 104 ?·cm. When a coil is embedded in this composite magnetic body, a miniature magnetic element can be obtained that has a high inductance value and is excellent in DC bias characteristics.