NMRV NRV SERIES WORM GEAR SPEED REDUCER According to European standard of similar product,we adopt high-quality artificial oil,imported famous brand seal parts and manufacture technology to produce square multi-placed reductor. Feature beautiful appearance,easy installation,compact structure,low noise and high efficiency.
NMRV worm gear reducer absorbs advanced technology at home and abroad. It has a novel and unique “square box” external structure. The box is beautiful in shape and is made of high quality aluminium alloy by die casting.
NMRV RV series structure drawing
NMRV Model & Marker

NMRV-063-30-VS-F1(FA)-AS-80B5-0.75KW-B3

NMRV
Worm geared motor

NRV
Worm reduction unit

063
center dictance

30
Reduction ratio

VS
Double input shaft
F1(FA)
Output flange

AS
Single output shaft 
AB
Double output shaft

PAM
Fitted for motor coupling
80B5
Motor mounting facility

0.75KW
Electric motor power
B3
Mounting position

NMRV NRV SERIES WORM GEAR SPEED REDUCER FEATURES:● The weight of the NMRV reducer is relatively light. The shell is made of aluminium alloy. It has the advantages of light weight, superior strength, exquisite appearance, high heat dissipation performance, long service life, no noise and so on. It is easy to connect with the motor.
● NMRV reducer is a more practical transmission equipment, and in the appearance design and its integration are more in line with the needs of the public than other types of reducers.●The application field and popularity of the RV reducer made of aluminium alloy are even better than other types of reducer. It is a kind of reducer with high practicability, and also a combination of advanced technology at home and abroad.● NMRV reducer is very convenient to connect with ordinary motor, CVT, China u joint drive shaft T1 Agricultural Machinery PTO Shaft agricultural tractor tires 7.50 16 flange electromagnetic clutch brake unit, and does not need coupling. Suitable for all-round installation, and the output torque is relatively large, work fairly smoothly and so on.NMRV NRV SERIES WORM GEAR SPEED REDUCER MOUNTING DIMENSIONS 

Single  Step Worm Gear Reducer
Output Flange Mounting Dimensions
Torque  Arm
HIGH QUALITY OUTPUT SHAFTNew standard axle, multi-precision machining, through rigorous dynamic and static balance test, to ensure low noise and smooth operation of reducer.
PRECISION BEVEL GEARworm and gear: The gears are made of 10-1 tin bronze (with high strength, corrosion resistance and excellent casting properties).
Worm adopts 20CR: carburized alloy structural steel (with high strength, hardenability, wear resistance).
High Speed Bearings and CZPT Seals:Use synthetic oil (friction agent: reduce temperature rise, reduce friction).
HIGH QUALITY SHELL MATERIALHigh-quality aluminium alloy casting: lightweight, rust-free, high output torque.Military manufacturing technology: smooth transmission, low noise, good heat dissipation effect.Fine appearance: beautiful and durable, small size, suitable for all-round installation.
Our Company ZheJiang CZPT GEAR TECHNOLOGY CO., LTDOur company is located in the city of HangZhou, ZheJiang Province of China. We handle the products of power transmission, Casting Iron Speed Reducer Reduction Gear Boxes Wp Series Worm Gearbox our lines mainly cover series products in speed reducers, gearboxes , associated electricial motors and other power transmission accessories. Based on the versatile functions, our products can be utilized in many fields: machines of waste water treatment, dredgers, chemical industry, cranes, metal working mills, conveyors, paper industry, cement industry, cableways and so on.With the excellent quality and reasonable price , our products enjoy a good reputation from customers and the peers all over the world. Furthermore, the R&D investment are annually increasing for the purpose of better meeting the new demands of our customers and adapting the new tendency of the industry.Depending on the principles of honestly operating and mutual benefit, We sincerely look forward to cooperating with you.
Application areaNMRV NRV worm gear speed reducer.
It is widely used in many fields such as metallurgy, mine, printing, chemical industry, textile, foodstuff, medicine, rubber and plastic, Hot Sale Auto Transmission Systems 29X49X25 Transmission Wheel Hubs Outer Constant Velocity Joint Shaft CV Joint SWIFT 25-49-29 etc.
Packing&Transportion PACKING AND TRANSPORTION●Packaging: In order to ensure the integrity of product appearance, we will choose cartons, wooden pallets and wooden pallets according to customer needs.●Delivery time: Each reducer is manufactured and tested in accordance with strict and fixed procedures to ensure that the quality is correct before leaving the factory and delivery on time.●Transportation mode: We will choose the most suitable mode of transportation for our customers according to the weight and size of the goods. We can also choose the mode of transportation according to the needs of our customers.●Receiving and after-sales service: After receiving the goods, please check whether they are in good condition. We will provide customers with perfect after-sales service.
FAQQ1: Are you a trading company or a manufacturer ?A: We are a manufacturer in ZheJiang Province, China. Our company owns the ability of manufacturing, processing, designing and R&D. We welcome your visit.Q2: How we select models and specifications?A: According to the specific details of the demands from the part of enquiry, we will recommend the products’ models upon synthesizing the factors of field of products usage, power, torque arm and ratio…Q3: How is your price? Can you offer any discount?A: Our prices are always competitive. If the customer can place a large order, we surely will allow discount.Q4: How long should I wait for the feedback after I send the enquiry?A4: We will reply as soon as possible, 12 hours at most.Q5: What is your product warranty period?A: We have the certifications of ISO9001,CE, SGS.Q6: What industries are your gearboxes being used?A: Our gearboxes are widely applied to metallurgical equipment, mining equipment, automation equipment, UDL Motor Speed variator for power transmission gearboxes food machinery, packaging equipment, tobacco equipment and so on.

How to Choose the Right Worm Shaft

You might be curious to know how to choose the right Worm Shaft. In this article, you will learn about worm modules with the same pitch diameter, Double-thread worm gears, and Self-locking worm drive. Once you have chosen the proper Worm Shaft, you will find it easier to use the equipment in your home. There are many advantages to selecting the right Worm Shaft. Read on to learn more.

Concave shape

The concave shape of a worm’s shaft is an important characteristic for the design of a worm gearing. Worm gearings can be found in a wide range of shapes, and the basic profile parameters are available in professional and firm literature. These parameters are used in geometry calculations, and a selection of the right worm gearing for a particular application can be based on these requirements.
The thread profile of a worm is defined by the tangent to the axis of its main cylinder. The teeth are shaped in a straight line with a slightly concave shape along the sides. It resembles a helical gear, and the profile of the worm itself is straight. This type of gearing is often used when the number of teeth is greater than a certain limit.
The geometry of a worm gear depends on the type and manufacturer. In the earliest days, worms were made similar to simple screw threads, and could be chased on a lathe. During this time, the worm was often made with straight-sided tools to produce threads in the acme plane. Later, grinding techniques improved the thread finish and reduced distortions resulting from hardening.
When a worm gearing has multiple teeth, the pitch angle is a key parameter. A greater pitch angle increases efficiency. If you want to increase the pitch angle without increasing the number of teeth, you can replace a worm pair with a different number of thread starts. The helix angle must increase while the center distance remains constant. A higher pitch angle, however, is almost never used for power transmissions.
The minimum number of gear teeth depends on the angle of pressure at zero gearing correction. The diameter of the worm is d1, and is based on a known module value, mx or mn. Generally, larger values of m are assigned to larger modules. And a smaller number of teeth is called a low pitch angle. In case of a low pitch angle, spiral gearing is used. The pitch angle of the worm gear is smaller than 10 degrees.

Multiple-thread worms

Multi-thread worms can be divided into sets of one, two, or four threads. The ratio is determined by the number of threads on each set and the number of teeth on the apparatus. The most common worm thread counts are 1,2,4, and 6. To find out how many threads you have, count the start and end of each thread and divide by two. Using this method, you will get the correct thread count every time.
The tangent plane of a worm’s pitch profile changes as the worm moves lengthwise along the thread. The lead angle is greatest at the throat, and decreases on both sides. The curvature radius r” varies proportionally with the worm’s radius, or pitch angle at the considered point. Hence, the worm leads angle, r, is increased with decreased inclination and decreases with increasing inclination.
Multi-thread worms are characterized by a constant leverage between the gear surface and the worm threads. The ratio of worm-tooth surfaces to the worm’s length varies, which enables the wormgear to be adjusted in the same direction. To optimize the gear contact between the worm and gear, the tangent relationship between the two surfaces is optimal.
The efficiency of worm gear drives is largely dependent on the helix angle of the worm. Multiple thread worms can improve the efficiency of the worm gear drive by as much as 25 to 50% compared to single-thread worms. Worm gears are made of bronze, which reduces friction and heat on the worm’s teeth. A specialized machine can cut the worm gears for maximum efficiency.

Double-thread worm gears

In many different applications, worm gears are used to drive a worm wheel. These gears are unique in that the worm cannot be reversed by the power applied to the worm wheel. Because of their self-locking properties, they can be used to prevent reversing motion, although this is not a dependable function. Applications for worm gears include hoisting equipment, elevators, chain blocks, fishing reels, and automotive power steering. Because of their compact size, these gears are often used in applications with limited space.
Worm sets typically exhibit more wear than other types of gears, and this means that they require more limited contact patterns in new parts. Worm wheel teeth are concave, making it difficult to measure tooth thickness with pins, balls, and gear tooth calipers. To measure tooth thickness, however, you can measure backlash, a measurement of the spacing between teeth in a gear. Backlash can vary from one worm gear to another, so it is important to check the backlash at several points. If the backlash is different in two places, this indicates that the teeth may have different spacing.
Single-thread worm gears provide high speed reduction but lower efficiency. A multi-thread worm gear can provide high efficiency and high speed, but this comes with a trade-off in terms of horsepower. However, there are many other applications for worm gears. In addition to heavy-duty applications, they are often used in light-duty gearboxes for a variety of functions. When used in conjunction with double-thread worms, they allow for a substantial speed reduction in one step.
Stainless-steel worm gears can be used in damp environments. The worm gear is not susceptible to rust and is ideal for wet and damp environments. The worm wheel’s smooth surfaces make cleaning them easy. However, they do require lubricants. The most common lubricant for worm gears is mineral oil. This lubricant is designed to protect the worm drive.

Self-locking worm drive

A self-locking worm drive prevents the platform from moving backward when the motor stops. A dynamic self-locking worm drive is also possible but does not include a holding brake. This type of self-locking worm drive is not susceptible to vibrations, but may rattle if released. In addition, it may require an additional brake to keep the platform from moving. A positive brake may be necessary for safety.
A self-locking worm drive does not allow for the interchangeability of the driven and driving gears. This is unlike spur gear trains that allow both to interchange positions. In a self-locking worm drive, the driving gear is always engaged and the driven gear remains stationary. The drive mechanism locks automatically when the worm is operated in the wrong manner. Several sources of information on self-locking worm gears include the Machinery’s Handbook.
A self-locking worm drive is not difficult to build and has a great mechanical advantage. In fact, the output of a self-locking worm drive cannot be backdriven by the input shaft. DIYers can build a self-locking worm drive by modifying threaded rods and off-the-shelf gears. However, it is easier to make a ratchet and pawl mechanism, and is significantly less expensive. However, it is important to understand that you can only drive one worm at a time.
Another advantage of a self-locking worm drive is the fact that it is not possible to interchange the input and output shafts. This is a major benefit of using such a mechanism, as you can achieve high gear reduction without increasing the size of the gear box. If you’re thinking about buying a self-locking worm gear for a specific application, consider the following tips to make the right choice.
An enveloping worm gear set is best for applications requiring high accuracy and efficiency, and minimum backlash. Its teeth are shaped differently, and the worm’s threads are modified to increase surface contact. They are more expensive to manufacture than their single-start counterparts, but this type is best for applications where accuracy is crucial. The worm drive is also a great option for heavy trucks because of their large size and high-torque capacity.