Slewing bearing

About: Slewing bearing is a research topic. Over the lifetime, 1498 publications have been published within this topic receiving 5309 citations.

Wind generator set and the variable propeller system thereof

Abstract: The utility model discloses a variable propeller system used in wind generator set. the system includes a wheel hub (1), a slewing bearing (2) on the wheel hub (1); and an oil cleaning component (3), the oil cleaning component (3) is disposed on the wheel hub (1) and contacts with any part of the slewing bearing (2). In this way, when the slewing bearing (2) has oil stain needed to be cleaned, the oil stain can be transferred to the oil cleaning component (3) or other proper positions due to the oil cleaning component (3) contacts with the slewing bearing (2), the overall oil cleaning of the slewing bearing (2) can be realized by the rotation of the slewing bearing (2) around the wheel hub, at the same time, the wind generator set can normally work, thereby improving the work efficiency of air blowers. The utility model also discloses a wind generator set equipped with the variable propeller system.

An application of mathematical morphology operators as features extraction method for low speed slew bearing condition monitoring

Abstract: This paper presents a new application of mathematical morphology (MM) operators for low speed slew bearing condition monitoring. The MM operators were used as a signal processing step and feature extraction method for bearing vibration signals. Four basic MM operators; erosion, dilation, closing and opening, were studied. This paper also investigates another potential MM operator, namely gradient operator. Two common time domain features in bearing condition monitoring, namely root mean square (RMS) and kurtosis, were extracted from the processed signal. The study shows that the changes in bearing condition can be clearly detected from the extracted features (RMS and kurtosis) of the MM operators compared to RMS and kurtosis features extracted from the original vibration signal. The application of the method is demonstrated with laboratory run-to-failure slew bearing data acquired on a daily basis.

Bridge detection vehicle for multiple working conditions

Abstract: The utility model discloses a bridge detection vehicle for multiple working conditions, and belongs to the technical field of bridge detection. The bridge detection vehicle comprises a chassis (1), an auxiliary frame (2), a turnover mechanism (6), a lifting oil cylinder (7), a vertical arm (8), a second slewing bearing (9), a second slewing mechanism (10) and a telescopic arm (11). A first slewing bearing (3) is provided with a first slewing mechanism (4), an amplitude variation oil cylinder (5) capable of adjusting the turnover angle is arranged between the first slewing mechanism and the turnover mechanism (6), and the first slewing mechanism is mainly composed of a base (41), a connecting body, a main arm (43), a slewing lifting oil cylinder (45) and a slewing amplitude variation oil cylinder (46). According to the bridge detection vehicle for the multiple working conditions, the first slewing mechanism is functionally divided to form multiple independent units through integration, movement mechanisms are arranged and designed among the units, three degrees of freedom, namely lifting, amplitude variation and stretching are added, the span height and span width capability of the detection vehicle is greatly improved, and the application range of the bridge detection vehicle is enlarged.

Dynamic Factors for Offshore Cranes

Abstract: The paper presents the theoretical background to a study of the dynamic effects experienced by cranes on offshore platforms. The study was initiated to review cranes operating in Bass Strait, Australia. A simplified dynamic model of a luffing crane has been used to derive the magnitude of the dynamic factor which occurs when a load undergoing sinusoidal motion is lifted. A theoretical idealisation of a crane was established to determine stiffness. Calculated values of crane stiffness are presented to show the influence of crane properties and operating radius. Dynamic factors for six different cranes are given, showing the influence of wave conditions, geometry and reeving of the hoist system. Overturning moments occurring on the slewing ring are considered in relation to their original design values.

Ball-type slewing bearing with asymmetric raceway and processing method thereof

Abstract: The invention discloses a ball-type slewing bearing with an asymmetric raceway and a processing method thereof; the raceway of the slewing bearing is the asymmetric raceway; the upper part and the lower part of the slewing bearing are asymmetric and the inner ring raceway and the outer ring raceway are asymmetric; the detailed structure parameters of the ball-type slewing bearing are as follows: the ratio of curvature (the curvature radius ratio between the raceway and the steel ball, i.e. R/r) ranges from 1.02 to 1.08, the contact angle alpha has a value range from 55 degrees to 65 degrees and the cross angle beta has a value range from 10 degrees to 20 degrees. According to the detained structure parameters, a numerically controlled lathe is adopted to conduct semi-finishing of the raceway firstly; next, intermediate frequency quenching is conducted on the raceway, with quenching hardness being 57 HRC to 62 HRC; and finally, a specific numerically controlled grinder for the raceway is adopted to shape and grind the asymmetric raceway. The slewing bearing can improve the state of the contact stress between the steel ball and the raceway and increase the carrying capacity by 35 percent.