A crankshaft lathe is a specialized type of machine tool that is used to machine the connecting rod neck and crank arm side of internal combustion engines and air compressor crankshafts.
Lathe features
Crankshaft lathes have distinct features that set them apart from general lathes. These features are:
(1) Specialized chucks are used. In addition to the typical clamped chuck, the chuck also has the ability to adjust eccentricity and azimuth. The chuck is mounted on the spindle of the machine tool and the slide table can be moved on the radial rail of the chuck body to adjust the eccentricity. The chuck holds the workpiece and can rotate around its own axis to adjust the azimuth.
(2) Large crankshaft lathes do not have a rear ejector pin but instead have a central frame support with the same number of crankshaft journals at the lower part of the workpiece.
(3) The crankshaft lathe has a multi-tool machining semi-automatic cycle for improved productivity. It typically has front and rear tool holders, allowing for simultaneous processing of the connecting rod neck and arm side. The machine starts automatically and stops automatically after processing.
These characteristics exist due to the poor rigidity of crankshaft designs and manufacturing, the misalignment between the crankshaft connecting rod neck and crankshaft rotation line, and the varying azimuth angles of crankshafts.
Conditions of Use
To ensure proper use of the crankshaft lathe, the following conditions must be met:
Environmental Requirements for the Machine’s Location:
- The machine tool should be located away from sources of vibration, and direct sunlight and heat radiation should be avoided to prevent the influence of moisture and air flow.
- If there is a vibration source nearby, anti-vibration grooves should be placed around the machine to prevent its influence on the machining accuracy and stability of the machine tool.
Power Requirements:
- The crankshaft lathe is typically installed in a machine shop, which often has large fluctuations in ambient temperature and power supply voltage.
- To ensure proper operation of the CNC system, the location of the crankshaft lathe must have strict control over the power supply voltage, with fluctuations kept within the allowable range and relatively stable.
Temperature Conditions:
- The ambient temperature of the crankshaft lathe should be less than 30 degrees Celsius, and the relative temperature should be less than 80%.
- The numerical control electric control box is equipped with an exhaust fan or cooling fan to maintain a constant operating temperature or small temperature difference for the electronic components, particularly the central processing unit.
- Excessive temperature and humidity can reduce the lifespan of the control system components and increase the likelihood of failure. Dust can also cause bonding on the integrated circuit board and short circuits.
Instructions for Use:
- The user must not make arbitrary changes to the parameters set by the manufacturer in the control system. These parameters are directly related to the dynamic characteristics of the machine’s various parts.
- Only the gap compensation parameter can be adjusted based on the actual situation.
- The user must not change the machine attachments arbitrarily, such as using a hydraulic chuck that exceeds the specifications. The manufacturer’s selection of accessories considers the matching of parameters among links. Blind replacement can cause mismatches and even result in an unforeseen accident.
- The pressure of the hydraulic chuck, hydraulic tool holder, hydraulic tailstock, and hydraulic cylinder must be within the allowable stress range, and no increase is allowed.
