Gear grinding process is the method of finish grinding gear teeth and is a significant step when building high precision gearing. Gears with precision ground teeth work more softly and consume more evenly than gears with cut teeth.
Gear grinding process is often done as a step in the gear manufacturing method, and we also give a gear grind only service. Through our Pro-Gear division, we can give external gear grinding settings with fast turnaround time and cheap tooling cost.
We have vast experience, and constantly make investments in state-of-the-art gear grinding technology. This succession ensures we can provide high accuracy, high quality, custom ground gears that adhere to strong customer terms.
What is gear grinding?
Gear teeth can be created entirely by grinding, completely by cutting, or by first cutting and then grinding to the expected dimensions.
Normally, gear grinding process is done after gear has been cut and heat-treated to high hardness. Grinding is essential for parts above 350 HB (38 HRC) where cutting becomes very hard. Teeth produced by grinding are normally those of definite pitch, where the number of metal extracted is very small.
Also, grinding of gears becomes the method of choice in the matter of fully hardened steels, where it may be hard to have the heat-treat deformity of gear within fair limits.
Lastly, in a few cases, medium-hard gears that could be achieved by cutting are filed to save costs on costly cutting tools such as hobs, shapers or shaving cutters, or to gain the desired surface finish or efficiency on a difficult-to-manufacture gear.
Basic Methods for Gear Grinding
The two basic techniques for gear grinding are
- Form grinding (non-generating) and
- Generation grinding
Form grinders utilize a disc wheel to grind both facets of the space between two gear teeth, and have an involute figure dressed into the top of the wheel; a generating grinding ring, on the other hand, is straight.
The major problem of grinding gears is their cost. Because materials must be excluded in small supplements when grinding as compared to cutting, the former is more costly. Also, ground gears draw more inspection than cut gears and may include both magnetic particle review as well as macro etching with dilute nitric acid.
Benefits of Gear Grinding
In gear manufacturing, gear grinding is a finishing method which utilizes abrasive wheels to exclude small variations on gear teeth. It is generally known to be the most perfect way to end a high precision gear, giving a more accurate tooth finish than gear cutting.
Due to their specific gear geometry, ground gears offer great meshing effectiveness and stable operation, working more quietly and consuming more evenly than cut gears. They can also manage greater loads and are helpful when large amounts of energy are required. For these purposes, they are often seen in equipment that requires high performance and safety.
Various types of gears
There are several types of gears such as helical gears, spur gears, bevel gears, gear rack, etc. These can be broadly divided by looking at the points of axes such as parallel shafts, crossing shafts, and non-intersecting shafts.
Spur gears are the most extensively used gears that can produce high accuracy with comparatively easy production methods. They have the quality of having no pressure in the axial bearing (thrust load). The larger of the meshing set is called the gear and tinier is called the pinion.
Helical gears are practiced with parallel bars similar to spur gears and are cylindrical gears with folding tooth lines. They have more genuine teeth meshing than spur gears and have excellent quietness and can carry higher loads, making them fit for high-speed demands.
Same sized and formed teeth cut at regular distances along a flat surface or a vertical rod is called a gear rack. A gear rack is a cylindrical gear with the extent of the pitch cylinder being constant. By meshing with a circular gear pinion, it transforms rotational movement into linear motion.
Bevel gears have a cone-shaped form and are utilized to transmit force between two poles which cross at one point (intersecting shafts). A bevel gear has a funnel as its pitch surface and its teeth are cut on the cone.
Spiral Bevel Gear
Spiral bevel gears are beveled gears with rounded tooth lines. Due to greater tooth contact ratio, they are better than straight bevel gears in power, strength, vibration, and sound. On the other hand, they are more complicated to produce. Also, because the teeth are bent, they produce thrust capabilities in the axial direction.