Masao Ogasawara

Nippon Steel (Japan)

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

Development of Nippon Steel premium connection

Masao Ogasawara Fujimasa Koyama Kazushi Maruyama Eiji Tsuru Yoichi Yazaki

New premium connections for oil country pipes were developed and the gas tightness, anti-galling capability and joint strength were studied experimentally and theoretically. The sealing mechanism was the two-step-pin-nose radial metal seal and composed of two shoulders and stable gas tightness was ensured by the secondary reserve shoulder even if the primary shoulder was deformed. The stress relief mechanism was provided to alleviate the local pressure on the seal. The sealing area surface was processed by Cu, Zn plating or phosphating depending on the service environment to increase the anti-galling capability. The API Buttress type thread was used because of the easy application and sufficient joint strength. This connections were successfully applied to drill-strings used under severe conditions where stress varied much by thermal expansion and contraction, such as in steam injection wells containing heavy gravity crude oil in California, U.S.A. (13 figs, 3 tabs, 2 photos, 6 refs)

Galling

Buttress

Source

Cite

Citations (0)

Performance of Tubular Connections Under the Loading Conditions of Horizontal Wells

SPE Drilling & Completion (1996)

Eiji Tsuru Masakatsu Ueno Masao Ogasawara Tetsuo Yonezawa

Summary This study deals with the negative effects of bending stress and casing wear on tubular connections. The joint strength of three connection types, API long round thread (LTC), API buttress thread (BTC), and typical premium joint (PJ), was measured with a full-size combined loading tester. Measurements were also made for the connections simulating wear induced by drilling operations. The sealing ability of the connections was evaluated under bending and wearing conditions. Numerical simulations were undertaken to investigate the failure mechanism of the connections. The results indicate that LTC joint strength is lowered by bending, though that of BTC and PJ is not degraded. Joint strength is reduced in direct proportion to the wear area ratio of the pipe body. In sealing ability, only the premium connection maintained leak resistance under combined loading with bending. Axial loading is more detrimental to sealing integrity than the bending moment. In conclusion, the connection performance data can be useful in designing safer horizontal well casings.

Interference fit

10.2118/27485-pa

Cite

Citations (2)

Integrity of internally coated premium connections

Katsuomi Tamaki Arata Nakamura Tugio Miyagawa Toshihiro Tamaki Masao Ogasawara

A research project was established for developing highly corrosion-resistant oil country tubular goods with thin layers on their inside surfaces. This report studied the integrity of internally coated joints as a premium connection, which was verified by anti-galling, sealability, and full scale SSC tests. Pin was coated with Plasma Transferred arc hardfacing (PTH), Ion plating, Plasma CVD, or Planer magnetron sputtering process (PMSP), while coupling was done with PTH, or Cylindrical magnetron sputtering process (CMSP). Coating material was TiN (titanium nitride) or UNS N10276. Anti-galling properties were studied by twenty-time Makeup/Breakout tests. Sealability was studied with a dedicated thermal-cycle-tester under thermal-cycling with internal pressure and tension, and static combined loads of internal pressure, tension, and bending. Full scale SSC test was carried out under the condition of 200 C-1.1 MPa H{sub 2}S-1.5MPa CO{sub 2}-20%NaCl. Final selected coatings were as follows. Coating material was UNS N10276. The processes for pin were PTH for inside surface, and PMSP for threads, respectively; those for coupling were PTH for inside surface and CMSP for threads. No galling, no leak, and no corrosion attack were observed in the established connection.

Galling

Internal pressure

Internal stress

Source

Cite

Citations (1)

Solubility of V4C3 in α-Iron

Transactions of the Iron and Steel Institute of Japan (1968)

Hiroshi Sekine Tohru Inoue Masao Ogasawara

10.2355/isijinternational1966.8.101

Cite

Citations (21)

Additional Snoek Peak due to Carbon in Fe-V-C Alloys

Japanese Journal of Applied Physics (1967)

Hiroshi Sekine Tohru Inoue Masao Ogasawara

Carbon fibers

10.1143/jjap.6.272

Cite

Citations (8)

Optimum Application of Environmentally Safe Compound Greases for Casing and Tubing

SPE Drilling & Completion (1996)

Masao Ogasawara Fujimasa Khoyama

Summary It is now expected to prevent the contamination of the environment from the use of pipe dope or compound grease in oilfield drilling operations. Recently, some environmentally safe compound greases have been commercially developed and are available, but it is not generally known what effect they will have on the connection performance. This paper will discuss a detailed experimental study of the performance of these greases to investigate the galling tendency and sealing capability of American Petroleum Inst. (API) buttressthread connections (BTC) and metal/metal seal premium connections. It is already known that greases without both lead and zinc can be used for a single makeup of these connections, but some improvements were expected in the antigalling performance for multiple makeups. Greases without lead or without both lead and zinc are not satisfactory for preventing hydrostatic leakage in buttress connections because of the lack of buildup of powders for thread clearance, and the addition of graphite in substituting for these metal powders tends to produce galling. Thus, the ratio of solid/liquid elements and the roughness of the graphite grain will be important in the improvement of existing greases.

Galling

Workover

Leakage (economics)

Grease

10.2118/22555-pa

Cite

Citations (1)

Investigation of service performance of casing pipe in thermal well environment and its application to critical design of thermal wells

Nippon steel technical report. Overseas (1990)

Eiji Tsuru Fujimasa Kohyama Yoichi Yazaki Syuichi Takesue Masao Ogasawara

Source

Cite

Citations (0)

The Crack Tip Opening Angle (CTOA) of the Plane Stress Moving Crack

Journal of the Society of Naval Architects of Japan (1982)

Masao Ogasawara Hiroyuki Okamura

Recently, Crack Tip Opening Angle (CTOA) was proposed by C. F. Shih et al to describe the instability criterion of ductile crack propagation during plane strain (fiat crack) condilions, and was derived by J. R. Rice analytically by means of the slip line field theory and the incremental theory of plasticity. CTOA appears to be applicable in (some or most) cases, but does not accurately describe the plane stress growing crack (slant crack).Unstable ductile crack propagation of the plane stress crack is widely studied for the safe design of highly pressurized gas pipelines. The impact absorption energy of the Charpy test is well correlated to the fracture arresting properties of the structures, but the mechanics of the fracture are not yet well established.In this paper, CTOA of the plane stress growing crack is derived from the plane stress plasticity of perfectly plastic materials by Sokolovsky's approach. Our proposed modification of CTOA expressed as follows :CTOA= (α/σ0) (dJ/dl) +β (σ0/E) ln (eR/r)where, β=1.40 under the plane stress conditions.CTOA in the Dugdale model is also defined and compared with the results of lat, oratory test. The results show that α=0.5, and β=1.27 for plane stress crack growth. These analyses give similar results to those obtained by Rice et al for CTOA under plane strain conditions, that is, α=0.65 from the experimental results and β=5.08 from the slip line theory.The CTOA obtained for plane stress ductile crack growth is applied to the wide plate tensile crack growth test. The results of the present analysis coincide well with those of the plane stress finite element method (FEM) computed by T. Kanazawa et al. The phenomena of plane stress ductile crack propagation are also explained by the CTOA criterion under plane stress conditions.

Plane stress

10.2534/jjasnaoe1968.1982.238

Cite

Citations (0)

Crack Initiation at Notches in Low Cycle Fatigue

ICF3, Munich (Germany)#TAB#1973 (1974)

Masao Ogasawara Mototosi Adachi Masato Nagao Volker Weiß

Low-cycle fatigue

Source

Cite

Citations (7)

The Fracture of Tempered Martensite

Transactions of the Japan Institute of Metals (1968)

Sh ocirc ichi Matsuda Tohru Inoue Masao Ogasawara

Observations were made on the fracture surface of tempered martensite of a low-carbon nickel steel. Impact test data were correlated with details of fracture surface and microstructure. It is shown that cleavage microcracks initiate in large ferrite grains, i.e., first-formed large martensite plates; the dominant factor leading to the ultimate cleavage fracture from these microcracks is the mean length of a cleavage crack facet, which is much larger than the width of martensite needles or plates and is varied considerably with the prior austenite grain size.

Cleavage (geology)

10.2320/matertrans1960.9.343

Cite

Citations (30)