Abstract: A hand position control device includes a mode switching unit that is capable of switching between a normal hand movement mode and a manual hand position setting mode and a control unit that sets a pulse width of a driving pulse to be output to a coil of a motor that rotates a hand and sets a manual pulse width of the driving pulse in the manual hand position setting mode to be larger than a normal pulse width of the driving pulse in the normal hand movement mode.

Abstract: An abrasion-resistant welded steel pipe having a base plate and a weld metal: consists essentially of 0.05 to 0.2 wt. % C, 0.5 to 2 wt. % Si, 0.5 to 2.5 wt. % Mn, 0.02 to 2 wt. % Al, the balance being Fe and inevitable impurities; and the steel pipe has a Vickers hardness of at least 200. The abrasion-resistant welded steel pipe can further contain at least one element selected from the group consisting of 0.05 to 1 wt. % Cu, 0.05 to 2 wt. % Ni, 0.05 to 2 wt. % Cr, 0.05 to 1 wt. % Mo, 0.005 to 0.1 wt. % Nb, 0.005 to 0.1 wt. % V, 0.005 to 0.1 wt. % Ti, 0.0003 to 0.002 wt. % B.

Abstract: A grease composition sealed in a rolling contact bearing contains a base oil in the form of a mixture of an alkyldiphenylether oil and a poly-.alpha.-olefin oil. The weight ratio of the former to the latter is between 20:80 and 80:20. 5-40% by weight of thickening agent which is at least one of an aromatic diurea compound and an aromatic urea-urethane compound is added to the base oil. Further, a passivation oxidizing agent and an organic sulfonate are added.

Abstract: A method of longitudinally seam-welding steel pipes comprises the steps of providing a conductive net-like enclosure tube around a cable for supplying a direct electric current from the power source to the welding head; and conducting a direct electric current through the enclosure tube and through the steel pipe in a direction opposite to that in which the direct current runs through the cable. Apparatus for longitudinally seam-welding steel pipes comprises an electrical cable coupled to a welding head, a net tube surrounding the cable, and a device for supplying a direct electric current to the cable in a first direction and to the net enclosure tube and steel pipe in the opposite direction. The direct currents flowing in the enclosure tube and in the steel pipe is adjustably controlled to minimize the magnitude of a magnetic field created around the net enclosure tube and producing a welded steel pipe seam.

Abstract: Circular pipe of large diameter progressively formed of flat stock, the pipe having a single longitudinal seam is seam-welded by preparing welding grooves such that the inner groove is smaller in size and angle than the outer groove, sequentially carrying out submerged arc welding on the inner welding groove, and large current MIG welding to then first layer of the outer welding edge and a submerged arc welding to a second layer thereof.

Abstract: In longitudinally seam-welding a pipe-blank for welded steel pipe from the inside along a groove by the GMA welding process which comprises using direct electric current supplied to a plurality of consumable electrodes in tandem through at least one cable as the welding current, at least two even-numbered consumable electrodes are used, half of said consumable electrodes being connected to said direct current so as to be positive in polarity and the remaining half of said consumable electrodes being connected to said direct current so as to be negative in polarity, to enable lines of magnetic force produced by said direct electric current for welding flowing through said at least one cable introduced into said pipe-blank to cancel each other, thereby preventing magnetization of said pipe-blank and the resulting magnetic arc blow of the welding arc.

Abstract: In longitudinally seam-welding a pipe-blank for welded steel pipe from the inside along a groove by the reverse-polarity GMA welding process comprising using direct electric current supplied to a consumable electrode through a cable as the welding current with said consumable electrode as the anode, the direction of said direct electric current for welding flowing through said cable introduced into said pipe-blank is set in the same direction as that of welding, thereby preventing occurrence of a magnetic arc blow of the welding arc from said consumable electrode toward the upstream side of the welding direction, i.e., in the opposite direction to that of welding.

Abstract: After longitudinally seam-welding a pipe-blank for welded steel pipe from the inside along a groove by the arc welding process which comprises using direct electric current supplied to a consumable electrode through a cable as the welding current, the polarity of said consumable electrode applied for said longitudinal seam-welding is switched over to the opposite polarity, an arc from said consumable electrode is ignited again on a tab plate attached to the end of said pipe-blank on the completion side of said longitudinal seam-welding to cause a direct electric current for eliminating magnetism to flow through said cable in the opposite direction to that of said direct electric current for welding, thereby eliminating residual magnetism in said pipe-blank produced by said direct electric current for welding flowing through said cable introduced into said pipe-blank during said longitudinal seam-welding.