Abstract: A thermal insulation coating member includes: a substrate having a surface; a binding layer on the surface, and a thermal insulation layer on the binding layer. The thermal insulation layer includes: a first ceramic layer including a plurality of first flat pores, the plurality of first flat pores being inclined at a first angle with respect to the surface and extending in a first direction; and a second ceramic layer including a plurality of second flat pores, the plurality of second flat pores being inclined at a second angle with respect to the surface and extending in a second direction. The second angle differs from the first angle, the second direction differing from the first direction, or the second angle and the second direction respectively differing from the first angle and the first direction.

Abstract: A composition for downhill tool, a degradable rubber member for a downhole tool, a downhole tool, and a method for well drilling are provided which contribute to cost reduction and process shortening and can contribute to improvement of production efficiency. A degradable rubber and a degradation accelerator comprising at least one type of compounds represented by a general formula (I) below at the ratio from 0.1 to 20 parts by mass to 100 parts by mass of the degradable rubber, containing the composition for a down hole tool, i.e. degradable rubber member for a down hole tool, and a method for well drilling using them. (In Formula (I), R1 and R2 are each individually alkyl groups having from 1 to 5 carbons or phenyl groups).

Abstract: A composition for downhill tool, a degradable rubber member for downhole tool, a downhole tool, and a well drilling method are provided which contribute to cost reduction and process shortening and can contribute to improvement of production efficiency. The composition comprises a degradable rubber and a decomposition accelerator and comprises 0.1 to 20 parts by mass of at least one type of compound represented by the following general formula (I) per 100 parts by mass of the degradable rubber, the composition for a down hole tool includes the same, the degradable rubber member for down hole tool includes the same, and a well drilling method using the same. (In formula (I), R is an alkyl group having from 2 to 6 carbons).

Abstract: A stock shape for a downhole tool component includes a magnesium alloy including a phase containing 70 to 95 wt. % of magnesium in which 0 wt. % or more and less than 0.3 wt. % of a rare earth metal, a metal material other than the magnesium and the rare earth metal, and 0.1 to 20 wt. % of a degradation accelerator are distributed, and the stock shape has an average particle size of the metal material of 1 to 300 ?m, tensile strength of 200 to 500 MPa, and a degradation rate in a 2% potassium chloride aqueous solution at 93° C. of not less than 20 mg/cm2 and not greater than 20000 mg/cm2 per day. Accordingly, a downhole tool having high strength and being readily degradable is established.

Abstract: A plug for well drilling includes a mandrel and at least one diametrically expandable annular rubber member and at least one slip disposed on an outer circumferential surface orthogonal to an axial direction of the mandrel; (i) the mandrel being formed from a degradable material; and (ii) the at least one diametrically expandable annular rubber member being formed from a degradable rubber material having a rate of decrease of not less than 5% in 50% strain compressive stress after immersion in water at a temperature of 150° C. for 24 hours relative to the compressive stress before immersion; and/or having a rate of loss of mass of from 5 to 100% after immersion in water at a temperature of 150° C. for 72 hours relative to the mass before immersion. A well drilling method includes a step of isolating a borehole using the plug for well drilling, part or all of the plug being degraded thereafter.

Abstract: Provided is a rubber member for downhole tools, of which a decrease rate of 50% strain compressive stress after immersion for 24 hours in 150° C. water relative to 50% strain compressive stress before immersion is not less than 5%, and preferably not less than 50%. The rubber member is suitable for a seal member, ball sealer, ball seat, and a protecting member. Also provided is a downhole tool comprising the rubber member, and a method for recovering a hydrocarbon resource using the downhole tool.

Abstract: A composition for downhill tool, a degradable rubber member for downhole tool, a downhole tool, and a well drilling method are provided which contribute to cost reduction and process shortening and can contribute to improvement of production efficiency. The composition comprises a degradable rubber and a decomposition accelerator and comprises 0.1 to 20 parts by mass of at least one type of compound represented by the following general formula (I) per 100 parts by mass of the degradable rubber, the composition for a down hole tool includes the same, the degradable rubber member for down hole tool includes the same, and a well drilling method using the same. (In formula (I), R is an alkyl group having from 2 to 6 carbons.

Abstract: Provided is a rubber member for downhole tools, of which a decrease rate of 50% strain compressive stress after immersion for 24 hours in 150° C. water relative to 50% strain compressive stress before immersion is not less than 5%, and preferably not less than 50%. The rubber member is suitable for a seal member, ball sealer, ball seat, and a protecting member. Also provided is a downhole tool comprising the rubber member, and a method for recovering a hydrocarbon resource using the downhole tool.

Abstract: A thermal insulation coating member comprises: a substrate having a surface; a binding layer on the surface; and a thermal insulation layer on the binding layer. The thermal insulation layer includes: a first ceramic layer having a plurality of first flat pores, the first flat pores being inclined at a first angle with respect to the surface and extending in a first direction; and a second ceramic layer having a plurality of second flat pores, the second flat pores being inclined at a second angle with respect to the surface and extending in a second direction. The second angle differs from the first angle, the second direction differing from the first direction, or the second angle and the second direction respectively differing from the first angle and the first direction.

Abstract: A degradable rubber member for a downhole tool formed from a rubber material containing from 0.1 to 20 parts by mass of a degradation accelerator relative to 100 parts by mass of a degradable rubber (optionally containing other rubber materials and/or reinforcing materials), of which, preferably, the decrease rate of the mass or the 50% strain compressive stress after immersion for 24 hours in 150° C. water is not less than 5%, and/or the mass loss rate after immersion for 72 hours in 150° C. water is from 5 to 100%, and further, as desired, the tensile fracture strain at 66° C. is not less than 50%, the 70% strain compressive stress is not less than 10 MPa, and the compressive fracture strain is not less than 50%; a degradable seal member or a protecting member for downhole tools comprising such a rubber member; and a downhole tool such as a plug for well drilling, and a method for well drilling.

Abstract: A degradable seal member for downhole tools, the member being a diameter-expandable annular seal member, the diameter-expandable annular seal member comprising: two or more annular members distributed along an axial direction, the annular members being formed from a degradable polymer material having hardness in a range from A60 to D80; a plug for well drilling; and a method for well drilling using the degradable seal member for downhole tools.

Abstract: A stock shape for a downhole tool component includes a magnesium alloy including a phase containing 70 to 95 wt. % of magnesium in which 0 wt. % or more and less than 0.3 wt. % of a rare earth metal, a metal material other than the magnesium and the rare earth metal, and 0.1 to 20 wt. % of a degradation accelerator are distributed, and the stock shape has an average particle size of the metal material of 1 to 300 ?m, tensile strength of 200 to 500 MPa, and a degradation rate in a 2% potassium chloride aqueous solution at 93° C. of not less than 20 mg/cm2 and not greater than 20000 mg/cm2 per day. Accordingly, a downhole tool having high strength and being readily degradable is established.

Abstract: A composition for downhill tool, a degradable rubber member for a downhole tool, a downhole tool, and a method for well drilling are provided which contribute to cost reduction and process shortening and can contribute to improvement of production efficiency. A degradable rubber and a degradation accelerator comprising at least one type of compounds represented by a general formula (I) below at the ratio from 0.1 to 20 parts by mass to 100 parts by mass of the degradable rubber, containing the composition for a down hole tool, i.e. degradable rubber member for a down hole tool, and a method for well drilling using them.

Abstract: A solidification- and extrusion-molded article of polyglycolic acid, which is formed of a resin material containing polyglycolic acid, the polyglycolic acid having a melt viscosity of 200 to 2,000 Pa·s, and has a thickness or diameter of greater than 100 mm but not greater than 500 mm. A downhole tool or a component thereof and a ball sealer for petroleum excavation are formed by cutting the solidification- and extrusion-molded article. A method for manufacturing the solidification- and extrusion-molded article of polyglycolic acid and a method for manufacturing a ball sealer for petroleum excavation.

Abstract: A poly-L-lactic acid (PLLA) solid-state extrusion molded article having a weight average molecular weight of from 100,000 to 380,000 and a melt viscosity of from 20 to 2,000 Pa·s (at a temperature of 240° C. and a shear rate of 120 sec?1) and having an L-form content of from 80 to 100%, the article having a thickness or diameter of from 10 to 500 mm and a tensile strength of from 5 to 100 MPa at a temperature of 66° C.

Abstract: A solidification- and extrusion-molded article of polyglycolic acid, which is formed of a resin material containing polyglycolic acid, the polyglycolic acid having a melt viscosity of 200 to 2,000 Pa·s, and has a thickness or diameter of greater than 100 mm but not greater than 500 mm. A downhole tool or a component thereof and a ball sealer for petroleum excavation are formed by cutting the solidification- and extrusion-molded article. A method for manufacturing the solidification- and extrusion-molded article of polyglycolic acid and a method for manufacturing a ball sealer for petroleum excavation.

Abstract: Provided are a molded product for well drilling comprising a reactive metal and a degradable resin composition that promotes a degradation reaction of the reactive metal, preferably a degradable resin composition comprising a degradable resin that generates acid upon degradation or a degradable resin composition containing a degradable resin and an inorganic material or an organic material that promotes degradation of the reactive metal; a molded product for well drilling which is a downhole tool or a downhole tool member; and a method for well drilling that uses said molded product for well drilling.

Abstract: Described are a molded product having an effective thickness of 1 mm or more, the molded product being formed from an aliphatic polyester resin composition containing from 1 to 30 parts by mass of a carboxylic acid anhydride and preferably further containing from 1 to 50 parts by mass of at least one type of a short fiber reinforcing material, a thermoplastic elastomer, or an acrylic rubber core-shell polymer per 100 parts by mass of an aliphatic polyester resin containing not less than 50 mass % of a polyglycolic acid resin, the effective thickness being 1 mm or more; a downhole tool for hydrocarbon resource recovery formed from the molded product having an effective thickness of 1 mm or more; an aliphatic polyester resin composition for the downhole tool member for hydrocarbon resource recovery; and a well drilling method.

Abstract: A ball sealer for hydrocarbon resource recovery, characterized by being obtained by coating a spherical core that comprises at least one layer comprising a disintegrable aliphatic polyester resin with a resin material that has higher impact resistance than the aliphatic polyester resin and by having a diameter of not less than approximately 25 mm (1 inch). This ball sealer has a large diameter, retains the property of being disintegrable after fracturing, and has impact resistance which makes the ball withstand high-velocity loading. The sealer is suitable for use in hydraulic fracturing, which is commonly used for recovering hydrocarbon resources including petroleum and gases. This large-diameter ball sealer can be efficiently formed with high dimensional accuracy by a method including at least one insert injection molding step.

Abstract: A fiber formed from a resin that degrades in treatment fluid for hydrocarbon resource recovery, an oligomer component content of a resin forming an outer surface of the fiber being not greater than 1 mass %, and a birefringence of the fiber being not less than 0.02; a method for manufacturing a degradable fiber for use in well treatment fluid, the oligomer component content of a resin that forms an outer surface of an undrawn yarn obtained in a spinning step being not greater than 1 mass %, and a birefringence of a drawn yarn before heat treatment in a drawing step being not less than 0.02; and a well treatment method using the well treatment fluid containing the degradable fiber for use in well treatment fluid and a proppant.