The highly competitive global market requires gear manufacturers to continually break the limits of increased productivity and lower production costs, which means high-speed hobbing must be performed with advanced hobs made of high-quality materials and protected with high-performance coatings. Due to the high price of advanced tools, some production plants are reluctant to use efficient hobs because they do not fully analyze all aspects of the production process to determine the correct cost calculation method - from calculating the total cost to calculating each piece of machining cost.

In order to achieve higher gear cutting efficiency, the design of the hob is tending to develop an efficient, multi-headed hob. The shank hob is made of integral tool steel and has a smaller diameter and is usually longer than a perforated hob. When mounted on a hobbing machine, they are positioned by the shank at both ends rather than being mounted on the mandrel like a perforated hob. For example, the blue flag Fette indexable carbide heavy duty cutting hob design is based on the combination of economical indexable carbide inserts and the well-known hobbing advantages, which can be used at high cutting speeds within a specified time. A large amount of metal is removed, and regrind and recoating are necessary for conventional hobs and are not necessary here. Significant savings in grinding costs and tool change time, which will reduce machine investment, thereby reducing plant construction and realizing significant cost savings for users; Gleason Corp.'s Genesis shank hob uses D The drive mechanism uses the entire surface contact of the hob key to transmit torque. In general, the planar-to-plane drive mechanism used on most machine tools tends to have slight misalignment on the contact surface under the action of the torque generated by the high stress line contact.

Integral shank hobs are typically used to machine worm gears, requiring a larger diameter of the hob than the diameter of the worm gear being machined. The optimized design of the shank hob is best suited for high volume, high efficiency machining. Large diameter, large pitch gears (such as gearboxes for truck gearboxes or mining machinery) are usually machined with perforated hobs.

For shank hobs and perforated hobs, the factors that can reduce cutting time include increasing feed rates, hob speeds, and increasing the number of hobs. In order to optimize the performance of the hob, the hob designer tried to use a small diameter hob because at a given surface speed (sfm), the smaller the diameter of the hob, the higher the cutting speed. Since the shank hob has a small diameter and no holes, it has a larger length than a perforated hob of similar diameter, so that more movable cutting zones can be obtained, and the hob can be cut more once per pass. Multiple workpieces. A hob with sharp cutting teeth moves along its axial direction into the cutting zone.

Glenn Schlarb, design manager at Gleason, explains that “the high productivity of the shank hob is the result of more moving positions along the hob in each pass and because of the high wear resistance. Hob material and tool coating increase the number of passes for the hob, allowing each hob to process more workpieces."

The hobbing process can be used with or without coolant. However, many users prefer dry hobbing because it eliminates environmental pollution and saves on the costs associated with handling coolant. In order to protect the cutting edge under high-speed dry hobbing conditions, dry hobbing requires the hob to have a high-quality coating with high temperature stability and low thermal conductivity.

Since the shank hob has a monolithic structure and has fewer parts for mounting it on the hobbing machine, its assembly rigidity is superior to that of the perforated hob. The hob can be used to detect sharpening, mounting and measurement accuracy while being mounted between the top ends. Compared to perforated hobs, the shank hob eliminates the cumulative runout error between the hole and the mandrel and the sway error caused by the spacer and the mounting nut.

The high-quality steel grades used to make shank hobs have high wear resistance and high levels of room temperature hardness and red hardness at cutting temperatures. While high-quality steels and coatings cost more than lower-performance materials, they can produce smaller-diameter shank hobs with higher cutting speeds, which reduces cycle times and costs per part. Under the right processing conditions, the cost per processing is usually greater than the cost per tool, which can reduce the total processing cost per workpiece.

In hobbing, it is important to use the right tool coating to increase productivity and reduce machining costs. In some machining applications, tool life can be doubled, saving tool costs and reducing tool change. The number of times reduces downtime.

Dr. Dennis Quinto, technical director of Oerlikon Balzers Coating, points out that the preparation of the cutting edge has a major impact on the performance of the coating, which is often an uncontrolled factor in tool performance. Sharp cutting edges produce lower cutting forces and lower cutting heat, but thinner coatings increase the risk of cutting edge chipping and are therefore only suitable for small feed rates; passivated cutting edges The upper coating is thicker and has more stable chipping resistance, but the cutting force is also larger; the chamfered and passivated cutting edge has the most stable chipping resistance, so it is very suitable for hard and brittle tool materials ( Such as cemented carbide) and high feed rate cutting.

Since the cutting speed and depth of cut should be reduced as the tensile strength of the workpiece increases during hobbing, the proper coating can be used to increase the cutting speed (and in some cases the feed rate can be increased). The PVD coating provides protection for almost all hobs. Standard TiN coatings are effective for low speed hobbing with lubricants; TiCN coatings increase the hardness and wear resistance of the hobs for abrasive workpieces; TiAlN coatings are developed for dry cutting and are excellent Toughness and high temperature resistance. The new AlCrN coatings recently developed for dry cutting have superior wear resistance, heat resistance and oxidation resistance.

Outdoor Post Light

An Outdoor Post Light is a type of Lighting Fixture that is designed to be mounted on a post or pole outside of a building or in a yard or garden. These Lighting Products are typically used to provide illumination for outdoor spaces, such as driveways, walkways, and patios, and can also be used for security and safety purposes.

Outdoor post lights come in a variety of styles and designs, including traditional lantern-style lights, modern minimalist designs, and decorative fixtures with ornate details. They are available in different materials, such as metal, wood, and glass, and can be powered by electricity or solar energy.

When choosing an outdoor post light, it is important to consider the size and style of the fixture, as well as the amount of light it will provide. It is also important to choose a Outdoor Garden Light that is weather-resistant and durable enough to withstand the elements. The material of Outdoor Post Light is usually stainless steel, aluminum alloy and other durable materials, and the surface has been treated with anti-corrosion, sandblasting, etc., which has the characteristics of waterproof, windproof, and anti-corrosion, and is suitable for outdoor use.