cnc Internal Grinding Machine for Inner Bore Machining

Application of Internal Grinding Machine in High Precision Inner Bore Machining

In modern mechanical manufacturing, as components continue to develop toward high precision, high consistency, and high reliability, the quality of inner bore machining has become a critical indicator of overall product performance. As a key piece of equipment for achieving high precision inner bore machining, the internal grinding machine plays an important role in industries such as automotive, aerospace, engineering machinery, and general manufacturing.

Definition and Machining Characteristics of Internal Grinding Machine

An internal grinding machine is a precision machine tool specifically designed for grinding the inner cylindrical surfaces and end faces of workpieces. It is mainly used for machining inner bores with cylindrical or conical structures. Compared with conventional cutting processes, internal grinding offers significant advantages such as high machining accuracy, low surface roughness, and excellent dimensional stability. Therefore, the internal grinding machine is particularly suitable for the finishing of high-precision components.

According to structural configuration and functionality, an internal grinding machine can be classified into a standard internal grinding machine and a universal internal grinding machine. Among them, the universal internal grinding machine is the most widely used, as it can process inner cylindrical surfaces, inner conical surfaces, and stepped end faces of shaft-type, sleeve type, and disc type workpieces.

Structural Advantages of Horizontal CNC Internal Grinding Machine

A horizontal internal grinding machine usually adopts a dual axis CNC configuration and is specially designed for multi step bore and end face grinding of tubular, disc, and shaft workpieces. While ensuring machining efficiency, this type of internal grinding machine effectively controls concentricity and perpendicularity, meeting the requirements of high precision assembly.

The machine bed of the internal grinding machine features a newly designed reinforced heavy duty structure optimized through finite element analysis. This design provides excellent load-bearing capacity, vibration resistance, and anti-overturning torque. The high rigidity bed structure ensures long term stable operation of the internal grinding machine and minimizes vibration impact on machining accuracy.

Precision Design of Guideways and Feed System

The guideways of the internal grinding machine are treated with plastic coating to reduce friction and are precision ground using high accuracy guideway grinders. This design ensures smooth motion, excellent feed responsiveness, and high positioning accuracy during micro-feed operations.

For the feed system, both the grinding wheel feed axis and the table reciprocating axis of the internal grinding machine are driven by AC servo motors. Power is transmitted through reducers and couplings directly to high precision ball screws, enabling fast response and precise positioning. This configuration allows the internal grinding machine to achieve stable and repeatable feeding accuracy during multi step bore grinding.

Spindle, Grinding Wheel, and Grinding System

The spindle system is the core component of the internal grinding machine and directly determines grinding quality and efficiency. The spindle drives the grinding wheel at high speed via a motor. Different grinding wheel materials and grit sizes can be selected according to workpiece materials and machining requirements, such as aluminum oxide grinding wheels and white aluminum oxide grinding wheels.

During the grinding process, vertical movement of the spindle controls grinding depth, while the reciprocating and rotational movements of the worktable ensure uniform contact between the grinding wheel and the inner bore surface. This coordinated motion enables the internal grinding machine to achieve high-quality inner bore grinding results.

Cooling System and Thermal Deformation Control

During internal grinding, high speed rotation of the grinding wheel generates a large amount of heat. If temperature rise is not effectively controlled, thermal deformation of the workpiece may occur, affecting machining accuracy. For this reason, the internal grinding machine is equipped with a complete cooling system. Coolant is continuously supplied to the grinding zone to provide cooling, lubrication, and chip removal, ensuring stable grinding quality.

CNC System and Ergonomic Design

Modern internal grinding machines can be equipped with mainstream CNC systems such as SIEMENS and FANUC to meet different user requirements for control accuracy, operating habits, and automation levels. The CNC system significantly improves machining flexibility and provides reliable support for complex inner bore and multi-process machining tasks.

In terms of appearance and safety, the internal grinding machine adopts a floor-mounted fully enclosed guarding design with a clean and modern appearance. A clear observation window allows operators to monitor the machining process while ensuring operational safety, fully meeting modern factory requirements for efficiency and safety.

Industrial Applications of Internal Grinding Machine

The internal grinding machine is widely used in automotive parts manufacturing, aerospace, high  end equipment manufacturing, and general machinery industries. In the automotive industry, the internal grinding machine is commonly applied to finish machining of engine cylinder liners, transmission components, and bearing inner rings. In aerospace applications, the internal grinding machine is used for high precision inner bore machining of structural and transmission components.

With continuously increasing demands for precision machining, the internal grinding machine is evolving toward CNC control, high rigidity, and high stability. Thanks to its stable structural design, precision feed system, and flexible CNC configuration, the horizontal CNC internal grinding machine has become an essential machine tool in the field of high-precision inner bore machining.