GB/T 41106.3-2021Large-scale amusement devices—Inspection, maintenance and repair—Part 3: Sort of rotary rides (English PDF)

C.1 Slewing Rings

C.1.1 Before the repair of slewing rings, in accordance with the design drawings, formulate a repair scheme; clarify the disassembly and installation procedures and steps, the necessary tools and equipment for construction, and the requirements, instruments and measuring tools for post-repair inspection.

C.1.2 The disassembled parts shall be checked and marked, and shall be kept in place during reassembly.

C.1.3 The tolerance of the inclination between the slewing bearing surface of the horizontal slewing mechanism and the horizontal plane shall not be greater than 1/1,000; the tolerance of the perpendicularity of the centerline of the central support shaft to the horizontal plane shall not be greater than 1/1,000.

C.1.4 The tolerance of the center distance of the turntable support shaft bearing or slewing ring of the vertical slewing mechanism shall not be greater than 1/1,000; the tolerance of the axis line levelness of the turntable support shaft bearing shall not be greater than 1/1,000; the tolerance of the axis line inclination of the turntable support shaft bearing shall not be greater than 1/1,500.

C.1.5 After disassembly, if the shafts, bearings and gears are found to be corroded, severely worn, deformed or broken, they shall be replaced.

C.1.6 The installation of the slewing rings shall comply with the stipulations of the design documents. The slewing rings shall be assembled in accordance with the process documents. After reassembly, the steering mechanism of the shaft shall be flexible and reliable, and there shall be no jamming.

C.2 Bearings

C.2.1 When the bearings are disassembled for inspection, the appearance records shall be properly kept; the remaining amount of lubricant shall be confirmed and sampled; the bearings shall be cleaned.

C.2.2 Bearing cleaning is divided into rough cleaning and fine cleaning. A metal mesh frame may be placed at the bottom of the used container. During rough cleaning, use a brush in the oil to remove grease and adhesions. If the bearings are rotated in the oil, prevent the rolling surface from being damaged by foreign objects. During fine cleaning, slowly rotate the bearings in the oil; the cleaning agent usually used is neutral diesel or kerosene that does not contain water, or warm lye as needed. After cleaning, immediately apply anti-rust oil or grease to the bearings.

C.2.3 In order to judge whether the removed bearings can be re-used, it is necessary to focus on checking the dimensional accuracy, rotational accuracy, internal clearance, as well as the mating surfaces, raceway surfaces, cages and sealing rings, etc. For large bearings, pay attention to check the appearance of rolling elements, raceway surfaces, cages and rib surfaces, etc.

C.3 Weld Defects

C.3.1 The weld defects (such as: columns, rotating arms and cylinder supports) of the rotary rides-type large-scale amusement devices are repaired by welding, and mainly through the mode of repair welding, with the purpose of repairing cracks and compensating for wear. The selection of welding materials, process, inspection and repair shall comply with the design documents and the stipulations of GB 8408, so as to control the welding quality.

C.3.2 For on-site welding, in accordance with the qualified welding processes and evaluation reports, the welding process shall be formulated. In addition, the welding shall be performed strictly in accordance with the welding process. If necessary, welding process specimens shall be produced on the site and pass the evaluation. On-site welding operation shall not be performed on the parts where on-site repair welding is not allowed in the design documents.

C.3.3 When one of the following circumstances occurs on the site of welding, corresponding protection measures shall be taken to satisfy the welding requirements, otherwise, welding shall not be performed:

a) wind speed: for gas shielded welding, greater than 2 m/s; for other welding methods, greater than 10 m/s;

b) relative humidity: greater than 90%;

c) rain and snow environment;

d) Weldment temperature is lower than -10 °C (-10 °C does not mean the temperature of the surrounding environment, but only the temperature of the welding area and the welding body. When the temperature of the welding specimen is lower than 0 °C, but higher than -20 °C, it shall be pre-heated to above 15 °C within a range of 100 mm of the welding area).

C.3.4 For long-distance welding (above 20 m) on the construction site, the length of cable extension shall be compatible with the cable diameter (cross-sectional area); the cables cannot be used in coils during operation. Before welding, the welding machine shall be debugged to ensure that the output voltage of the welding cable is consistent with the value displayed on the voltmeter of the welding machine.

C.3.5 The welding process shall have welding records. After welding, in accordance with the requirements of the design documents and relevant standards, conduct non-destructive testing […]