5 Core Advantages Of CNC Gear Machine For Processing Helical Gears

A transmission system needs to simultaneously meet the stringent requirements of high efficiency, smooth operation, quiet operation, and the ability to withstand enormous torque. Spur gears fall short in this situation, and the solution lies in a helical design – the helical gear.

However, manufacturing high-precision helical gears has always been a challenge in the gear manufacturing process.

This article explains in detail the salient points of gear cutting and manufacturing, explores in depth how modern gear machines, through digital innovation, have made the manufacturing of complex helical gears effortless, and describes why solutions from JS Precision are key to your success.

Core Answer Summary

Technical Fields	Core Solutions	Key Performance Indicators	Value Proposition
Helical Gear Design and Advantages	Utilizing a helical design, compared to spur gears.	It offers smoother transmission, quieter operation (noise reduction of 8-12 dB), and higher torque capacity.	Meeting the stringent requirements of high-speed, heavy-load, and low-noise operating conditions.
High-Precision Manufacturing Capability	Utilizing advanced gear machines such as CNC hobbing machines and gear grinding machines, coupled with strict process control.	Precision can reach ISO 4-6 level, tooth surface roughness Ra 0.4~0.8μm.	Ensuring precise gear meshing, extending service life, and improving transmission efficiency.
Overcoming Key Technical Challenges	Through precise control of the helix angle, heat treatment deformation compensation, and root cleaning technologies.	Solving problems such as vibration, tooth surface distortion, and stress concentration.	Solving urgent problems for customers, such as excessive vibration in electric vehicle drive gears, ensuring project success.
Service Provider Core Advantages (JS Precision)	With over 15 years of experience, we provide end-to-end services from design support to one-stop manufacturing.	We have the equipment capability to process helical gears with a module of 0.5-25 and a maximum diameter of 1500mm.	everaging our technical strength and extensive portfolio, we have become a reliable partner for numerous industry leaders.

JS Precision Team's Practical Summary: Five Advantages Of CNC Machining Of Helical Gears

With over 15 years of practical experience in the field of gear machining, JS Precision has served over 200 clients in aerospace, high-end automotive, and precision instrument industries while completing over 3000 helical gear machining projects.

For example, we machined helical gears with a module of 0.8 and a diameter of 200mm for an aerospace company, reaching ISO Level 4 ultra-high precision to meet the extreme operating conditions, we optimized the helical gear process for many electric vehicle manufacturers, reducing transmission noise by 8-12 decibels.

Our facility can machine helical gears at modules of 0.5-25 and with a maximum diameter of 1500mm, while keeping the tooth surface roughness stable at Ra 0.4~0.8 μm. Under special requirements, a mirror finish with Ra below 0.2 μm can be achieved.

This book was based on our experience extracted from real projects. Every point in the guide has evidence from data and case studies, so it can be trusted entirely.

JS Precision has years of experience in the provision of gear machining services, so one is assured of meeting all their requirements on precision and efficiency. You only need to provide the parameters of the gear you need, we will develop a solution quickly, and the cooperation can begin.

How Are Gears Made? A Deep Dive Into The Modern Gear Manufacturing Process

To understand how gears are made, you will have to delve into every step that the modern manufacturing process for gears involves. The following is the complete manufacturing journey of helical gears and JS Precision's quality control:

Manufacturing Stage	Key Contents	JS Precision's Quality Inspection Points
Material Selection and Blanks	40Cr, 20CrMnTi, selected alloy steel, forging can improve material density.	Material performance meets the standard through blank hardness testing and metallographic analysis.
Gear Cutting	CNC hobbing and gear shaping machines are used. CNC hobbing machines control the helix angle, and gear shaping machines are suitable for complex structures.	Ensure the basic tooth profile accuracy by detecting the tooth thickness deviation and measuring helix angle accuracy.
Heat Treatment	Carburizing and quenching increase tooth surface hardness to HRC58-62.	Hardness testing and initial deformation measurement prepare for finishing.
Finishing	Grinding improves accuracy to ISO 5-6 level, honing optimizes tooth surface roughness.	Tooth surface roughness testing and full tooth profile error measurement ensure final accuracy.

During the course of gear cutting and manufacturing, JS Precision combines "manufacturing" with "quality manufacturing." Correspondingly, each process is carefully tested to guarantee that every helical gear meets the standards.

We have a deep understanding of every detail of how gears are made.If you require a complete gear manufacturing process service, JS Precision offers one-stop support. From the point of your inquiry, we will be giving feedback on the process milestones and the time of delivery to give you complete peace of mind.

Figure 1: Gear manufacture depends on several core processes that transform raw materials into working components.

Helical Gears Vs. Different Gears: Why The Spiral Design Wins

Many customers want to know the differences between helical gears and other different gears when choosing a gear type. From the following comparison, one can see the advantages of helical gears, which reflect the five core advantages of CNC gear machining of helical gears:

Comparison Dimensions	Helical Gear (CNC Machining)	Spur Gear	Bevel Gear
Meshing principle	Involute spiral surface meshing, with long contact line and continuous meshing process.	Parallel tooth surface meshing has a short contact line and instantaneous meshing.	Conical surface meshing, which is capable of adapting to spatial intersecting shaft transmission requirements.
Transmission Smoothness	High, continuous meshing without impact, transmission fluctuation coefficient ≤0.05	High, continuous meshing without impact, transmission fluctuation coefficient ≤0.05	Medium, greatly affected by installation accuracy, transmission fluctuation coefficient 0.1-0.12.
Noise Level	Low, normally ≤65 dB at high speed (10000 rpm)	High, normally ≥75 dB at high speed (10000 rpm).	Medium to high-speed operation is normally around 70-75 dB.
Load capacity	High, large contact area, can withstand 30%-50% higher load than spur gears.	Low, small contact area, prone to wear, limited load capacity.	Medium, suitable for medium to light loads, prone to tooth breakage under overload.
Service life	Long, over 15000 hours under normal maintenance.	Short, normally 8000-10000 hours.	Medium, around 10000-12000 hours.
Operating conditions	High speed and heavy load, such as electric vehicle drive, reducer, wind turbine spindle.	Low speed and light load, such as ordinary conveyor belts, toys, small water pumps.	Inter_shaft transmission with spatial interlocking, such as automotive differentials, machine tool gearboxes.

The data shows that in high-speed and heavy-load conditions with noise requirements, helical gears are irreplaceable and only by fully understanding the characteristic differences of different gears can transmission failures caused by incorrect gear type selection be avoided.

If you are unsure how to choose the appropriate device from different gears, JS Precision engineers can analyze parameters such as load and speed to recommend the optimal gear type for you, making the device run more efficiently.

Figure 2: Helical gears feature teeth that are set at an angle. The teeth are bent into a helix shape, so the contact line between each tooth is inclined.

How To Select A Machining Solution For Your Gear Type

When selecting a solution in gear manufacturing, only the comprehensive judgment by key parameters could realize the maximum value of the gear machine. Different situations should be matched precisely:

Gear Type:

For high-precision helical gears, the "hobbing + grinding" solution is used, for example, in the wind power industry, the main shaft helical gears have to bear megawatt-level loads. This solution can control the tooth surface precision at ISO 5 level, and guarantee long-term stable transmission.

For simple spur gears, such as ordinary conveyor belt drive gears (speed ≤1000rpm), "hobbing + shaving" can meet the requirements and save the processing cost by 25%.

Module and Accuracy Grade:

Modules ≤ 2 and accuracy requirements of ISO 5 or higher are best for gear grinding. Examples include miniature helical gears in medical equipment, module 1.2, accuracy ISO 5. Gear grinding offers accurate correction of tooth profile errors.

In modules > 5 and with accuracy around ISO 7, hard turning is more efficient. For large gears in engineering machinery - module 8, accuracy ISO 7 - hard turning compared to gear grinding is 40% more efficient.

Materials and Batch Size:

Materials shall be heat-treatment steels such as 20CrMnTi. Allow a finishing allowance of 0.1 - 0.3mm to avoid insufficient dimensions after heat treatment.

During small batch production (less than 50 pieces), a flexible machining line should be adopted, with the unit processing cost at about 80-120 USD, in line with the needs of R&D customization. If the quantity to be ordered is more than 1,000, a dedicated line can be used to reduce the cost to around $40-60 per unit, which will help cut down the cost greatly.

The technical consulting team at JS Precision can help in optimizing your process solutions free of charge to find the best performance-cost ratio.

Because we are aware that manufacturing of gear is a systematic engineering process, and only solutions that meet the requirements can make manufacturing of gear projects more efficient, while also meeting the dual requirements of precision and efficiency in the gear manufacturing industry.

In case you have a special manufacturing of gear requirement, JS Precision's technical team will analyze your parameters for free. Please provide us with your gear drawings, specify your requirements, and our team will present the most optimized solution to you within 24 hours.

The Heart Of Precision: What To Look For In A Gear Machine For Helical Gears

Gear machines for machining helical gears require precise control and complex machining capability. Below are main equipment and their advantages. JS Precision also provides a professional maintenance system for this equipment:

CNC hobbing machine

Accurately control the helix angle, high machining efficiency, and suitable for mass production of helical gears.

The working units at JS Precision are equipped with a German Klingelnberg HNC 35 CNC gear hobbing machine with a positioning accuracy of ±0.001mm. There is also an automatic loading and unloading system, which is able to process 15-20 helical gears with a module of 2-5 per hour.

We carry out monthly checks and calibrations of the spindle run-out and guideway accuracy to ensure long-term stable operation.

CNC gear shaper

It is suitable to process internal helical gears and multigear sets of complex structure, enabling high-precision tooth profile machining.

The CNC gear shaper imported from Japan by JS Precision, NACHI NFX 250, can process internal helical gears with a maximum diameter of 500mm. It can control tooth profile error within 0.003mm, meeting the transmission requirements of hydraulic systems.

Five-axis machining center

It has significant advantages in the machining of complex helical surfaces, and they can realize multi-directional machining of helical gear teeth in a single operation, which reduces clamping errors (from 3 clamping attempts to 1) and improves the accuracy of machining.

High-quality gear machines imported from Germany and Japan are installed in JS Precision, which could satisfy all the manufacturing requirements about the machining of helical gears with different precisions and structures.

Figure 3: CNC machines are controlled by computer programs that ensure each gear is produced with exact specifications.

Conquering Complexity: Key Technical Challenges In The Manufacturing Of Gear

Manufacturing helical gears is a real technical challenge. Relying on professional equipment and technical experience, JS Precision overcame the challenges one by one and developed standardized solutions:

Helix Angle Precision Control

Helix angle deviation can lead to unstable meshing. We once machined helical gears for a high-speed rail bearing company, and the initial helix angle deviation reached ±8′, which caused excessive transmission vibration (>0.15mm/s).

By means of sampling inspections every 2 hours by the Zeiss Gear Measurement Center in Germany, and analysis of the cause of the deviation, the feed speed of the CNC hobbing machine was adjusted from 500mm/min to 450mm/min.

Ultimately, the deviation was controlled within ±5′, and the vibration value was reduced to below 0.08mm/s, meeting the requirements for high-speed rail operation.

Tooth Surface Distortion Control

Tooth surface twisting is prone to occur after heat treatment. The heat treatment deformation tendency is simulated with the help of UG simulation software before precision machining.

For example, during the machining of helical gears for an automotive transmission manufacturer, through simulation, it was shown that there was a tooth width twist of 0.012mm.

Based on this, 0.01mm anti-deformation allowance was reserved in the CNC programming and then precisely corrected with a Liebherr CNC gear grinding machine from Germany. The final twist was ≤0.005mm, thus ensuring smooth meshing.

Root Cleaning Technology

Root stress concentration shortens gear life. We use a dedicated carbide root cleaning tool, whose hardness is HRC 65. In addition, we perform customized CNC programming to suit the gear module. For modules 2-5, the root cleaning speed shall be controlled at 100-150mm/min, and the root fillet radius shall be kept within R0.3-R0.5mm.

It is precisely these technological strengths that solve the core difficulties in manufacturing of gear that have enabled JS Precision to establish a firm foothold in the gear manufacturing industry. We always believe that precise control over every step of gear cutting and manufacturing is the key to responding to technological iterations in the gear manufacturing industry.

Case Study: How JS Precision Solved A High-Speed Helical Gear Vibration Issue

Client Background and Challenges

A manufacturing company of luxury electric vehicles experienced excessive vibration and noise from helical gears in drive motors at high speeds, 10,000 rpm, reaching 78 decibels, far above the industrial standard of 65 decibels, greatly affecting the overall NVH performance of the vehicle for an annual production capacity of 100,000 units.

At the time, the client's flagship model was just three months away from market launch, if the problem was not solved, the production would be delayed, with an approximated daily loss of $200,000 per day at an average daily capacity of 300 vehicles, and at the risk of missing the market window.

Solution by JS Precision

First, we assembled a dedicated engineering team and brought a German Zeiss G 280 gear measuring center with an accuracy of 0.0001mm to the client's factory for test purposes within three days.

By simulating high-speed operation using ANSYS software, the problem was ultimately diagnosed as stemming from micron-level tooth profile deviation (0.008mm) and helix angle error (8′). The combined effect of these two errors increased meshing impact, thus generating high-frequency vibration and noise.

Then, back in the factory, after two days of reprogramming work on the Liebherr LC 800 CNC gear grinding machine, the optimal wheel dressing algorithm was realized, it adjusted the cutting path to segmented cutting, to precisely control the tooth surface topology. Gradual correction of the tooth profile and helix angle errors was performed.

Meanwhile, our materials engineers contacted the customer's heat treatment team and suggested that the quenching temperature be reduced from 880℃ to 875℃, with the holding time extended by 1 hour to decrease internal material stress.

This is in accordance with the subsequent finishing process parameters, by which a grinding feed rate of 80mm/min was used, so as to accurately correct residual errors. Trial production was completed in 7 days, during which time noise on the trial-produced gears dropped to 64 decibels, in line with standards.

Results and Value

The delivered helical gears maintained a stable transmission noise level of 62 decibels at the high speed of 10,000 rpm, not only meeting the customer's top-level quietness requirement but also being 3 decibels lower than the industry standard. The customer's flagship model was launched on schedule, first-month sales exceeded 12,000 units, far beyond the expected 8,000 units.

Then, the customer signed a 3-year long-term cooperation agreement with us, and purchased 8,000 sets of helical gears every month, and recommended us to their supply chain partners. Its purchasing director praised JS Precision: "They are not only a supplier but also a technical partner, helping us avoid significant losses at a critical moment."

Figure 4: The good machining performance of helical gears makes them smoother and quieter than other gears, resulting in smoother rolling.

The Future Is Now: Trends Shaping The Gear Manufacturing Industry

The gear manufacturing industry is developing towards intelligence and efficiency. The major trends are as follows:

• Smart Manufacturing & IoT: Real-time monitoring of the status of gear machine processing by sensors can collect data including information about cutting parameters and temperature, thus predicting maintenance to reduce equipment downtime.
• Superhard Tool Application: CBN tool application in processing helical gears. Higher hardness and wear resistance increase the effectiveness of processing by more than 30% and improve the quality of the tooth surface.
• Additive Manufacturing and Composite Processes: Employed in the manufacturing of gear molds or prototypes containing irregularly shaped cooling channels to shorten the R&D cycle, composite processes integrate multiple processing steps to improve production efficiency.
• Full-process Digital Twin: Simulate the gear manufacturing process 100% in the virtual world before processing, identify potential issues in the gear manufacturing process in advance, and achieve 'first piece, qualified'.

JS Precision continues to recognize these trends by adopting intelligent monitoring systems, superhard cutting tools, and investigating how it can leverage digital twin technology to give customers the most advanced manufacturing capabilities.

If you want to enjoy the latest technical services in the gear manufacturing industry, JS Precision can support that. After your consultation, relevant technical application case studies will be introduced to help you plan for future production.

FAQs

Q1: What is the minimum/maximum module and diameter range for CNC gear machines machining helical gears?

Helical gears with modules ranging from 0.5 to 25 and maximum diameters of up to 1500mm are machinable within JS Precision's wide reach of gear machines. Please send your specific parameters for more accurate confirmation.

Q2: Other than helical gears, are there different gears recommended?

Completely application condition-dependent. Application engineers at JS Precision can analyze the loads, speeds, space layout, etc., to recommend the best option between different gear type: spur gears, helical gears, and herringbone gears.

Q3: What accuracy is generally obtained when performing the machining of helical gears?

With the help of advanced CNC facilities and precision gear grinding, JS Precision maintains an average gear precision of ISO 5-6. Under special requirements, it can challenge ultra-high precision ISO 4 on critical projects, meeting high-tech demands in advanced fields.

Q4: What level of surface roughness can be achieved after machining helical gears?

By optimizing the cutting parameters and precision grinding/honing processes, JS Precision can usually control the surface roughness to Ra 0.4~0.8 μm. For extreme requirements, super-precision machining may achieve a mirror finish below Ra 0.2 μm.

Q5: Is heat treatment included in your gear manufacturing process?

JS Precision offers one-stop service, it focuses on high-precision machining and keeps long-term strategic partnerships with leading heat treatment plants to handle your supply chain and ensure smooth quality control.

Q6. How do you ensure the deformation of gears after heat treatment is within the controllable range?

JS Precision controls the deformation in a "systematic" way. First, it reserves anti-deformation allowance during the finishing stage, then it cooperates with a heat treatment plant using a controlled atmosphere furnace, and lastly, it conducts 100% inspection after heat treatment.

Q7: What are possible solutions for the "profile modification" technology of helical gears?

JS Precision offers tooth profile modification and helical profile modification to compensate for deformation under load, reduce meshing impact and noise, and make precision modifications to tooth surface topology with the use of advanced CNC gear grinding machines, customized to meet working conditions.

Q8: What is the typical cycle time for a helical gear project from order placement to delivery?

The cycle time depends on the complexity and quantity. Small-batch production of standard parameter helical gear (<50 pieces) normally takes 7-15 working days. Initial collaborations or complex projects require additional preparation time. After providing the drawings, a detailed plan can be provided.

Summary

Precision determines performance in the gear-manufacturing industry, so your partner of choice should be technically proficient and well-equipped. TechBullion has shared JS Precision's performance in precision manufacturing and supply chain optimization, which is highly consistent with our core philosophy of pursuing "reliability and efficiency" in helical gear machining.

With its deep understanding in every respect of gear cutting and manufacturing, and continuous investment in advanced gear machinery, JS Precision has gained the trust of numerous industry leaders as a reliable source for precision gear solutions.

Be it with custom solutions, resolving technical challenges, or meeting the latest processing demands, with JS Precision, you are guaranteed reliability and efficiency, thus giving your gear products an added advantage in the market.

Act now by clicking the link to upload your gear drawings or technical requirements. Our team will provide you with a preliminary process analysis and a highly competitive quote in under 24 hours. Let us work together to take your designs to the next level in power transmission.