Level is a commonly used gauge for measuring small angles. In the mechanical industry and instrument manufacturing (such as centrifugal pump manufacturing), it is used to measure the tilt angle with respect to the horizontal position, the flatness and straightness of the machine tool guide, the horizontal position and vertical position of the equipment installation. According to the shape of the level, it can be divided into: universal level, cylindrical level, integrated level, mini level, camera level, frame level, ruler level; according to the fixed way of the level can be divided into: adjustable level and not Leveling level.
Measuring methods
1. The two V-shaped measuring faces of the spirit level are the reference for measuring accuracy, and cannot be in contact with or rubbed against the rough surface of the work during the measurement. Care must be taken when placing it to avoid damage to the level due to scratches on the measuring surface and to cause undue measurement errors.
2. When measuring the vertical plane of the workpiece with the level meter, it is not possible to hold the part opposite to the auxiliary side, and forcefully push it to the vertical plane of the workpiece, which will affect the accuracy of the measurement due to the deformation of the level. The correct measurement method is to hold the inside of the sub-measurement surface by hand, so that the level is slid smoothly and vertically (adjusting the bubble in the middle position) on the vertical plane of the workpiece, and then read the number of movements of the bubble from the vertical level.
3. When using the level, ensure that the working surface of the level and the surface of the workpiece are clean to prevent the dirt from affecting the accuracy of the measurement. When measuring the horizontal plane, at the same measurement position, the level should be adjusted in the opposite direction and then measured. When moving the level, the level surface of the level is not allowed to rub against the surface of the workpiece and should be lifted up.
4. When measuring a workpiece with a large length, the workpiece can be divided into several size segments on average. The segmentation measurement method is used, and then the error coordinate map is drawn according to the measurement readings of each segment to determine the maximum number of errors. When the bed rail is inspected for straightness in the longitudinal vertical plane, the box level is placed longitudinally on the tool holder near the front rail, starting from the extreme position of the tool holder at one end of the spindle box, moving the tool holder from left to right, each The secondary movement distance should be approximately equal to the level of the border of the level (200mm). The level readings of the tool holder at each measured length position are recorded in turn. These readings are arranged in order, and the straightness error curve of the guide rail in the vertical plane is drawn in an appropriate ratio. The level meter reading is the ordinate. The level reading of the tool holder at the starting position is the starting point. The coordinate origin is used as a folding line segment. After each reading, the end point of the previous folding line segment is used as the starting point, and the folding line segment is drawn. The curve composed of line segments is the straightness curve of the guide rail in the vertical plane. The maximum coordinate value of the curve relative to the two ends of the curve is the straightness error of the full length of the guide rail. The difference between the two ends of the curve on the measured length of the two ends of the curve relative to the two ends of the curve is the local error of the guide rail.
5. The flatness inspection method of the working surface of the machine tool, the worktable and the saddle are respectively placed in the middle position of the stroke, and a bridge plate is placed on the work surface, and the level is placed thereon, and the bridge plates are respectively moved along the measurement directions of the drawings, each A level reading is recorded for the span of the bridge. The reference plane is established by three points A, B, and D on the work surface, and the coordinate values of the planes of each measurement point are obtained according to the reading of the level meter.
6. When measuring the verticality of large parts, use the level to coarsely adjust the reference surface to the level. The reference orientation is determined step by step on the reference surface and the measured surface, respectively, and the reference orientation is determined graphically, and then the perpendicularity error of the measured surface with respect to the reference is obtained.
When measuring small parts, first place the level on the reference surface, read the value at one end of the bubble, and then use one side of the level to close the vertical surface to be measured. The bubble deviates from the first (reference surface) reading, which is the measured surface.
