The process of honing the surface of a workpiece using a honing head is commonly utilized in various manufacturing industries, including automotive, tractor, hydraulic parts, bearings, aviation, and more, for honing the holes of the workpiece.
Honing machines are available in both vertical and horizontal types.
Different categories and characteristics
The vertical honing machine is designed for honing cylinders and tank holes and features a short spindle working stroke.
The honing head, equipped with an oil stone, rotates via the vertically positioned main shaft, while the vertical reciprocating feed motion is powered by the hydraulic device.
On the other hand, the horizontal honing machine has a longer working stroke and can be used to hone deep holes up to 3000 mm.
The honing head, which is positioned horizontally, only makes axial reciprocating motion, while the workpiece rotates via the main shaft. A central frame supports the workpiece, and a guide frame supports the honing rod, both arranged in the middle of the bed.
As the processing proceeds, the whetstone of the honing head is fed radially, thanks to the expansion and contraction mechanism. The workpiece gradually takes on the required size.
A new type of honing machine employs a hydraulic expansion and contraction honing head.
Most honing machines are semi-automatic, often equipped with automatic measuring devices, and can be integrated into automatic production lines.
Besides the honing machine for machining holes, there are external honing machines, bearing honing machines, flat honing machines, and curved honing machines for machining surfaces.
Hydraulic honing machine working principle
There are two general ways to increase or decrease the movement of the honing head:
- Constant Pressure Feed
- Quantitative Feed
Constant pressure feed is typically achieved through the use of hydraulic systems or springs.
On the other hand, quantitative feed is often achieved through the use of servo motors, stepper motors, or some other type of intermittent mechanism.
Manual feed mode can also be considered a form of quantitative feed.
Operating a honing machine is a technically demanding task that requires a skilled operator. This person should be trained in safe grinding operation and take the necessary precautions before proceeding.
Prior to operation, it is important to check the lubrication of the honing machine, especially the gearbox, to ensure there is sufficient lubrication oil. If no oil is present, it must be added to all the oil holes. The coolant should also be checked to ensure it is clean and filled to an appropriate level. Regular cleaning of the coolant is necessary to prevent any buildup of dirt.
Oil changes are required every two months of continuous use, and under normal circumstances, the oil should be changed once in the first quarter. #20 engine oil is generally used for hydraulic oil. When changing the oil, kerosene should be used to clean the oil filter and fuel tank.
After starting the machine, it should be idled for a period of time to remove any air from the hydraulic lines and to check that all parts are functioning properly. The temperature of the hydraulic oil should not exceed 60°C and should not go beyond 65°C. If the temperature is too high, the machine should be cooled or stopped.
It is important to check if the size of the oil stone is correct, if the honing head can expand and contract easily, and if the spring that secures the oil stone seat is firm. The rotary and reciprocating motion of the machine tool spindle should be adjusted to meet the requirements specified in the process specification.
Prior to operation, measurement tools should be prepared and the work of the door should be checked for normal operation. The accuracy of the gauge should also be up to standard.
Regular checks are necessary to ensure personal safety and proper functioning of the honing machine.