Abstract: Use of a steel alloy for well pipes of perforating units for perforation of borehole casings, with the steel alloy comprised, in mass-%, of Carbon (C) 0.12-0.25, Manganese (Mn) 0.5-2.0, Silicon (Si) 0.1-0.5, Nitrogen (N) 0.006-0.015, Sulfur (S) <0.005, Chromium (Cr) 0.1-1.5, Molybdenum (Mo), <0.3, Nickel (Ni) <1.0, Vanadium (V) <0.25, Niobium (Nb) 0.010-0.15, Titanium (Ti) 0.02-0.06, Boron (B) 0.001-0.006, Calcium (Ca) <0.0025, and iron as well as impurities resulting from smelting as remainder, wherein the steel alloy is heated at a heating rate of 1-100 K/s to an austenitizing temperature between 10 to 50° C. above its transformation temperature Ac3, and held at this austenitizing temperature between 0.

Abstract: The present invention pertains to a device for ultrasonic inspection of a weld seam of a longitudinally welded pipe for longitudinal defects with an inspection unit, which is relatively displaceable on a pipe surface on at least one side of the weld seam. The device also has two inspection heads in a tandem and spatially-variable arrangement, such that they can be positioned relative to the pipe surface to correspond to an intended acoustic irradiation angle independent of the diameter of the pipe. According to the invention, one inspection head acts as a transmitter and the other inspection head acts as a receiver. The device also has a pick-up connected to each of the two inspection heads, a coupling means connection connected to each pick-up, and a replaceable connecting element connected each pick-up via the coupling means connection.

Abstract: The present invention pertains to a device for the ultrasonic inspection of the weld seam of longitudinally welded pipes for longitudinal defects with an inspection unit, which can be relatively displaced on the surface of the pipe on at least one side next to the weld seam, comprising a pick-up with a coupling means feed, which said pick-up accommodates at least one inspection head with a modulator, which said inspection head touches the pipe surface and whose channel opens in the area of the modulator, wherein the inspection head can be arranged in a rigidly preset position relative to the pipe surface.

Abstract: A grab bucket, in particular motor-driven underwater grab bucket, has first and second half-scoops. The scoops can be moved relative to on another from an open position into a closed position by a hydraulic cylinder. The opening angle of the half-scoops is monitored by a sensor which is connected to a control and monitoring device. The sensor is integrated in the hydraulic cylinder and generates an actuating-travel signal which corresponds to the actuating travel of the hydraulic cylinder.

Abstract: A method of using a steel alloy, the steel alloy having a composition containing in mass %, 0.09-0.13% C, 0.10-0.50% Si, 1.10-1.80% Mn, max. 0.02% P, max. 0.02% S, 1.00-2.00% Cr, 0.20-0.60% Mo, 0.02-0.06 Al, 0.10-0.25% V, the balance iron and incidental impurities, includes the steps of forming a tube from the steel alloy; air hardening the tube in the presence of inert gas, and incorporating the tube in the production of a compressed gas container. The steel composition may also be used as material for producing formed structures in light weight steel construction.

Abstract: A monitoring device for motor-driven underwater grab bucket dredges contains a bucket gear suspended on a cable. The device ensures reliable monitoring and controlling of the operating condition of the bucket gear 4. There is at least one sensor connected to the grab bucket gear for sensing a measured value. There is a computer connected to the sensor for representing the measured value detected by the sensor.

Abstract: A floating grab installation for recovery of sand and gravel is disclosed. The installation includes a catamaran-type float or pontoon having a gripper and gripper support thereon. The gripper transfers the sand and gravel to an underwater tank having an endless bucket dredge which plunges to its lowest point.

Abstract: The cutoff device is provided for crane systems, especially a dredger to which a grab 1 is attached. Grab 1 has a cable 5 connected to it, which is guided over pulleys 4, 7 and kept under tension with the help of a weight 9. One of the two pulleys 4 is provided with an initiator 12 that has segments mounted on its periphery, so pulses are generated by the rotation of pulley 4 past the initiator and the drive mechanism is switched off when the pulses fail to occur.