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China Best Sales CHINAMFG Precision Rolled Ball Screw with Sleeve Type Nut for Motors (TXR Series, Lead: 1mm, Shaft: 4mm)

Product Description

 TXR Series Sleeve Type Single Nut Ball Screw (C5/Ct7/Ct10)
 

Table of Shaft dia. and Lead combination for Rolled Ball Screw
  Lead (mm)  
0.5 1 1.5 2 2.5 3 4 5 6 8 10 12 15 20 30
Shaft dia (mm) 4   /   /                      
5             /                
6   /   /         /   /        
8   /   / /     /   / / /      
10       /   / / / /   / / / /  
12       /             /        
13                       / / /  
14       /     /                
15               /     /     /  
16                              

Accuracy Class & Axial Clearance
 
Accuracy grade of TXR series(sleeve type single nut ball screw)are based on C5,Ct7 and Ct10(JIS B 1192-3). According to accuracy grade, Axial play 0.005(Preload :C5),0.02(Ct7) and 0.05mm or less(Ct10).

Material & Surface Hardness
 
TXR series (sleeve type single nut ball screw) of screw shaft screw material S55C (induction hardening), nut material SCM415H (carburizing and hardening), the surface hardness of the ball screw part is HRC58 or higher.

Shaft End Shape
 
The shape of the shaft end of the TXR series (sleeve type single nut ball screws) has been standardized.

Application:

1. Medical industry
2.Lithium battery industry
3.Solar photovoltaic industry
4. Semi conductor Industry
5. General industry machinery
6. Machine tool
7. Parking system
8. High-speed rail and aviation transportation equipment
9. 3C industry etc

Technical Drawing

Specification List

 

FACTORY DETAILED PROCESSING PHOTOS
 

HIGH QUALITY CONTROL SYSTEM

FAQ

1. Why choose CHINAMFG China?

  Over the past 14 years, CHINAMFG has always insisted that “products and services” start from Japanese industry standards,taking ZheJiang standards as the bottom line, actively invest in the development of new transmission components and self-experiment and test. With the service tenet of “exceeding customer expectations”, establish a “trusted” partnership.

2. What is your main products ?

We are a leading manufacturer and distributor of linear motion components in China. Especially miniature size of Ball Screws and Linear Actuators and linear motion guideways.  Our brand “KGG” stands for ” Know-how,” ” Great Quality,” and ” Good value”  and our factory is located in the most advanced  city in China: ZheJiang  with the best equipment and sophisticated technology, completely strict quality control system. Our aim is to supply world leader class linear motion components but with most reasonable price in the world.

3. How to Custom-made (OEM/ODM)?

If you have a product drawing or a sample, please send to us, and we can custom-made the as your required. We will also provide our professional advices of the products to make the design to be more realized & maximize the performance.

4. When can I get the quotation?
 
 We usually quote within 24 hours after we get your inquiry. If you are very urgent to get the price,please call us or tell us in your email so that we will regard your inquiry priority.

5. How can I get a sample to check the quality?

 After confirmation of our quoted price, you can place the sample order. The sample will be started after you CHINAMFG back our detailed technical file. 

6. What’s your payment terms?

  Our payment terms is 30% deposit,balance 70% before shipment. /* March 10, 2571 17:59:20 */!function(){function s(e,r){var a,o={};try{e&&e.split(“,”).forEach(function(e,t){e&&(a=e.match(/(.*?):(.*)$/))&&1

Precision: C7
Screw Diameter: 4mm
Flange: With Flange
Nut Number: Single
Rows Number: 3-Row
Nut Type: Sleeve Type Single Nut
Customization:
Available

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worm screw

How do you properly lubricate a worm screw and gear assembly?

Proper lubrication is essential for the smooth and efficient operation of a worm screw and gear assembly. Lubrication helps reduce friction, wear, and heat generation between the contacting surfaces, thereby extending the lifespan of the components. Here are the steps to properly lubricate a worm screw and gear assembly:

  1. Clean the Assembly: Before applying lubrication, ensure that the worm screw and gear assembly is free from dirt, debris, and old lubricant residues. Clean the surfaces using an appropriate cleaning agent or solvent, followed by a thorough drying process.
  2. Select the Right Lubricant: Choose a lubricant specifically designed for gear systems or worm screw applications. Consider factors such as viscosity, temperature range, load capacity, and compatibility with the materials used in the assembly. Consult the manufacturer’s recommendations or lubrication guidelines for the specific assembly to determine the suitable lubricant type and grade.
  3. Apply the Lubricant: Apply the lubricant to the contacting surfaces of the worm screw and gear assembly. Use an appropriate applicator, such as a brush, oil can, or grease gun, depending on the lubricant form (oil or grease) and the accessibility of the components. Ensure complete coverage of the gear teeth, worm screw threads, and other relevant surfaces. Pay attention to areas where the most significant friction and wear occur.
  4. Monitor the Lubricant Level: Check the lubricant level regularly to ensure an adequate supply. Depending on the application and operating conditions, lubricant consumption or degradation may occur over time. It is important to maintain the lubricant level within the recommended range to ensure proper lubrication and prevent excessive wear or overheating.
  5. Periodic Lubrication Maintenance: Establish a lubrication maintenance schedule based on the operating conditions and manufacturer’s recommendations. Regularly inspect the assembly for signs of lubricant degradation, contamination, or insufficient lubrication. Replace the lubricant as needed and follow the recommended intervals for lubricant replenishment or reapplication.
  6. Consideration for Grease Lubrication: If using grease as the lubricant, it is important to choose a high-quality grease suitable for worm screw applications. Grease provides better adhesion to surfaces and tends to stay in place, offering longer-lasting lubrication compared to oil. However, excessive grease accumulation or over-greasing should be avoided, as it can lead to increased friction and inefficiency.

It is crucial to follow the manufacturer’s guidelines and recommendations for lubrication specific to the worm screw and gear assembly. Different assemblies may have unique lubrication requirements based on their design, load capacity, operating conditions, and materials used. By properly lubricating the worm screw and gear assembly, you can ensure optimal performance, reduce wear, and extend the operational life of the components.

worm screw

Are there different types of worm screws available?

Yes, there are different types of worm screws available to suit various applications and requirements. The design and characteristics of a worm screw can vary based on factors such as the material used, the thread geometry, the type of worm wheel, and the intended application. Here are some common types of worm screws:

  1. Standard Worm Screws: Standard worm screws are the most commonly used type and are available in a wide range of sizes and materials. They typically have a single-start thread and are made from materials such as steel, stainless steel, or bronze. Standard worm screws are suitable for general-purpose applications where moderate precision and load capacity are required.
  2. Double-Enveloping Worm Screws: Double-enveloping worm screws, also known as hourglass worm screws, have a unique thread profile that improves contact and load distribution between the worm screw and the worm wheel. This design offers enhanced torque transmission, higher efficiency, and increased load-carrying capacity compared to standard worm screws. Double-enveloping worm screws are often used in heavy-duty applications, such as gearboxes and high-load power transmission systems.
  3. Low-Lead Worm Screws: Low-lead worm screws have a smaller thread lead angle compared to standard worm screws. This design reduces the amount of sliding contact between the threads of the worm screw and the teeth of the worm wheel, resulting in lower friction and improved efficiency. Low-lead worm screws are commonly used in applications where high efficiency and reduced heat generation are critical, such as in precision machinery and high-speed gear systems.
  4. Self-Locking Worm Screws: Self-locking worm screws are designed to have a high friction angle between the threads, making them capable of preventing reverse motion or backdriving. This self-locking feature eliminates the need for additional braking mechanisms or external locking devices in certain applications. Self-locking worm screws are commonly used in vertical lift systems, hoists, and other applications where holding the load position is essential.
  5. High-Precision Worm Screws: High-precision worm screws are manufactured to tighter tolerances and have improved accuracy compared to standard worm screws. They are designed to provide precise positioning and motion control in applications where high accuracy and repeatability are required. High-precision worm screws are often used in CNC machines, robotics, and other precision equipment.
  6. Customized Worm Screws: In addition to the standard types mentioned above, worm screws can also be customized to meet specific application requirements. Customized worm screws may involve variations in thread geometry, pitch, diameter, materials, or other parameters to suit unique applications or performance specifications.

The selection of the appropriate type of worm screw depends on factors such as the desired load capacity, efficiency requirements, backlash tolerance, positional accuracy, and environmental conditions. It is important to consult with manufacturers, engineers, or experts familiar with worm screw applications to determine the most suitable type for a specific application.

worm screw

What are the advantages of using a worm screw in gear systems?

Using a worm screw in gear systems offers several advantages that make it a preferred choice in certain applications. Here are some of the advantages of using a worm screw:

  1. High Gear Reduction: One of the primary advantages of a worm screw is its ability to provide a high gear reduction ratio in a single stage. The helical threads of the worm screw and the meshing teeth of the worm wheel create a significant reduction in rotational speed. This allows for efficient torque multiplication, enabling the transmission of high torque output from the worm screw to the worm wheel. The high gear reduction is beneficial in applications that require slow and powerful movements, such as lifting heavy loads or controlling conveyor systems.
  2. Compact Design: Worm screw mechanisms are known for their compact design. Compared to other gear systems, such as spur gears or helical gears, a worm screw setup can achieve a similar gear reduction with fewer components. This makes it a space-saving solution, especially in applications where limited space is available or where a compact design is desired.
  3. Self-Locking: The self-locking property of a worm screw is a significant advantage in many applications. Due to the helical shape of the threads, the worm screw has a natural tendency to hold its position and prevent backward rotation of the worm wheel. This self-locking feature eliminates the need for additional braking mechanisms or external locking devices, simplifying the overall system design and improving safety and stability in applications that require load holding or position locking.
  4. Right-Angle Transmission: Worm screw mechanisms provide motion transmission at a right angle, allowing for the transfer of motion between non-parallel shafts. This makes them suitable for applications where the input and output shafts are oriented perpendicular to each other. Examples include automotive steering systems, where the rotational motion from the steering wheel needs to be converted into lateral motion for steering the vehicle.
  5. Quiet Operation: Worm screw gear systems tend to operate quietly compared to other gear configurations. The helical threads of the worm screw and the meshing teeth of the worm wheel engage gradually, resulting in smoother and quieter operation. This can be advantageous in applications where noise reduction is desirable, such as in office equipment, appliances, or environments where low noise levels are required.

It’s important to note that while worm screw mechanisms offer these advantages, there are also some considerations to keep in mind. For instance, worm screws can have lower mechanical efficiency compared to other gear systems due to inherent friction between the threads and teeth, leading to energy losses. Additionally, they may exhibit a certain amount of backlash, which can affect precision and introduce a small amount of lost motion in the system. Nevertheless, the unique characteristics of worm screws make them a valuable choice in various applications where high gear reduction, self-locking, compactness, and right-angle transmission are essential.

China Best Sales CHINAMFG Precision Rolled Ball Screw with Sleeve Type Nut for Motors (TXR Series, Lead: 1mm, Shaft: 4mm)  China Best Sales CHINAMFG Precision Rolled Ball Screw with Sleeve Type Nut for Motors (TXR Series, Lead: 1mm, Shaft: 4mm)
editor by CX 2024-02-23

China Best Sales Brush 12V Gear High Torque Low Rpm Price Worm DC Screw Motors with Best Sales

Product Description

Brush 12v Gear High Torque Low Rpm Price Worm Dc Screw Motors

1.Features

1) Step Angle  Accuracy: ±5%
2) Resistance Accuracy: ±10%
3) Inductance Accuracy: ±20%
4) Temperature Rise: 80°C Max
5) Ambient Temperature: -20°C~+50°C
6) Insulation Resistance: 100MΩ Min., 500VDC
7) Dielectric Strength:  500VAC for 1 minute
8) Shaft Radial Play:  0.02Max (450g-load)
9) Shaft Axial Play: 0.08Max (450g-load)

2.Related Specifications

1) 42mm series

Model DMW421 DMW422 DMW423
Voltage V 24
No load speed rpm 5000 5000 5000
Rated torque Nm 0.063 0.094 0.125
Rated Speed rpm 4000 4000 4000
Rated Current A 1.7 2.5 3.5
Torque(max) Nm 0.19 0.27 0.38
Back-EMF constant V/Krpm 3.13 3.13 3.15
Torque Constant Nm/A 0.039 0.04 0.04
Resistance ohm 1.5 0.53 0.74
Weight Kg 0.3 0.4 0.5
Length mm 41 51 6

2) 70mmSeries

Model Rated Voltage No load
speed
Rated torque Rated Speed Rated
Current
Rated
power
     L
VDC RPM Nm rpm A W mm
DMW701 48 3500 0.5 3000 4.3 157 86
DMW702 48 3500 1 3000 8.7 314 116
DMW703 48 3500 1.5 3000 12.9 471 136

3) 80mmSeries

Model DMW801 DMW802 DMW803
Voltage V 24
No load speed rpm 4200 4200 4200
Rated torque Nm 0.25 0.5 0.75
Rated Speed rpm 3000 3000 3000
Rated Current A 5.2 10.5 15
Rated power W 79 157 236
Back-EMF constant V/Krpm 9 9.2 9.5
Torque Constant Nm/A 0.06 0.052 0.05
Resistance ohm 0.5 0.43 0.35
Weight Kg 1.6 2.2 3
Length mm 75 95 115

4) 86mmSeries

Model DMW861 DMW862 DMW863
Voltage V 48
No load speed rpm 3500 3500 3400
Rated torque Nm 1.0 1.8 2.5
Rated Speed rpm 3000 3000 3000
Rated Current A  8.6 14.8 20
Torque(max) Nm 3.0 5.4 7.5
Back-EMF constant V/Krpm 9.8 9.8 10
Torque Constant Nm/A 0.13 0.13 0.14
Resistance ohm 0.32 0.15 0.1
Weight Kg 2.2 3.2 4.2
Length mm 80 105 130

5) 60mmSeries

Model DMW601 DMW602 DMW603
Voltage V 36
No load speed rpm 4100 4100 4100
Rated torque Nm 0.25 0.5 0.75
Rated Speed rpm 3000 3000 3000
Rated Current A 3 6 9
Torque(max) Nm 0.75 1.5 2
Back-EMF constant V/Krpm 6.2 6.5 6.5
Torque Constant Nm/A 0.043 0.045 0.041
Resistance ohm 0.59 0.26 0.2
Weight Kg 0.9 1.2 1.6
Length mm 78 99 120

6) 57mm Series

Model DMW571 DMW572 DMW573 DMW574
Voltage V 36
No load speed rpm 5200 5200 5300 5400
Rated torque Nm 0.11 0.22 0.32 0.42
Rated Speed rpm 4000 4000 4000 4000
Rated Current A 1.8 3.2 4.7 6.5
Torque(max) Nm 0.3 0.5 0.8 1.2
Back-EMF constant V/Krpm 4.5 4.8 4.83 4.9
Torque Constant Nm/A 0.072 0.078 0.08 0.09
Resistance ohm 1.7 0.75 0.5 0.39
Weight Kg 0.45 0.8 1.1 1.4
Length mm 55 75 95 115

7) 57 High Torque

Model DMW571 DMW572 DMW573 DMW574
Voltage V 36
No load speed rpm 5200 5200 5200 5200
Rated torque Nm 0.14 0.28 0.43 0.49
Rated Speed rpm 4000 4000 4000 4000
Rated Current A 2.2 4.5 6.8 7.9
Torque(max) Nm 0.4 0.6 0.9 1.5
Back-EMF constant V/Krpm 4.5 4.8 4.83 4.9
Torque Constant Nm/A 0.072 0.078 0.08 0.09
Resistance ohm 2 0.9 0.7 0.5
Weight Kg 0.5 0.9 1.3 1.8
Length mm 55 75 95 115

3.Outlines/Drawings

4.About US

5.Main Products

HangZhou Shnmotor is a developing manufacturing and trading company which aims at the electrical products of refrigeration market.
We have a highly qualified team, which has over 8 years experience on Machinery designing, manufacturing, managing and customer service concept heart & soul.
ISO 9000 standard and 6S management guarantee the most effective quality control on every part and every process of the products. 

Our Main Products as below:
1)Brushless DC Motor
2)Setpping Motor 
3)AC Motor
4)Motor Group
(Motor+Reducer+Driver+Brake)

6.Application

Package and Shipping

1.FedEX / DHL / UPS / TNT for samples,Door to door service;
2.By sea for batch goods;
3.Customs specifying freight forwarders or negotiable shipping methods;
4.Delivery Time:20-25 Days for samples;30-35 Days for batch goods;
5.Payment Terms:T/T,L/C at sight,D/P etc.

FAQ
Q1. When can I get the quotation?
We usually quote within 24 hours after we get your inquiry. If you are urgent to get the price, please send the message on  and  or call us directly.

Q2. How can I get a sample to check your quality?
After price confirmed, you can requiry for samples to check quality.
If you need the samples, we will charge for the sample cost. But the sample cost can be refundable when your quantity of first order is above the MOQ

Q3. Can you do OEM for us?
Yes, the product packing can be designed as you want.

Q4. How about MOQ?
1 pcs for carton box.

Q5. What is your main market?
Eastern Europe, Southeast Asia, South America.

 
Please feel  free to contact us if you have any question.

 

Screw Shaft Features Explained

When choosing the screw shaft for your application, you should consider the features of the screws: threads, lead, pitch, helix angle, and more. You may be wondering what these features mean and how they affect the screw’s performance. This article explains the differences between these factors. The following are the features that affect the performance of screws and their properties. You can use these to make an informed decision and purchase the right screw. You can learn more about these features by reading the following articles.

Threads

The major diameter of a screw thread is the larger of the 2 extreme diameters. The major diameter of a screw is also known as the outside diameter. This dimension can’t be directly measured, but can be determined by measuring the distance between adjacent sides of the thread. In addition, the mean area of a screw thread is known as the pitch. The diameter of the thread and pitch line are directly proportional to the overall size of the screw.
The threads are classified by the diameter and pitch. The major diameter of a screw shaft has the largest number of threads; the smaller diameter is called the minor diameter. The thread angle, also known as the helix angle, is measured perpendicular to the axis of the screw. The major diameter is the largest part of the screw; the minor diameter is the lower end of the screw. The thread angle is the half distance between the major and minor diameters. The minor diameter is the outer surface of the screw, while the top surface corresponds to the major diameter.
The pitch is measured at the crest of a thread. In other words, a 16-pitch thread has a diameter of 1 sixteenth of the screw shaft’s diameter. The actual diameter is 0.03125 inches. Moreover, a large number of manufacturers use this measurement to determine the thread pitch. The pitch diameter is a critical factor in successful mating of male and female threads. So, when determining the pitch diameter, you need to check the thread pitch plate of a screw.
screwshaft

Lead

In screw shaft applications, a solid, corrosion-resistant material is an important requirement. Lead screws are a robust choice, which ensure shaft direction accuracy. This material is widely used in lathes and measuring instruments. They have black oxide coatings and are suited for environments where rusting is not acceptable. These screws are also relatively inexpensive. Here are some advantages of lead screws. They are highly durable, cost-effective, and offer high reliability.
A lead screw system may have multiple starts, or threads that run parallel to each other. The lead is the distance the nut travels along the shaft during a single revolution. The smaller the lead, the tighter the thread. The lead can also be expressed as the pitch, which is the distance between adjacent thread crests or troughs. A lead screw has a smaller pitch than a nut, and the smaller the lead, the greater its linear speed.
When choosing lead screws, the critical speed is the maximum number of revolutions per minute. This is determined by the minor diameter of the shaft and its length. The critical speed should never be exceeded or the lead will become distorted or cracked. The recommended operational speed is around 80 percent of the evaluated critical speed. Moreover, the lead screw must be properly aligned to avoid excessive vibrations. In addition, the screw pitch must be within the design tolerance of the shaft.

Pitch

The pitch of a screw shaft can be viewed as the distance between the crest of a thread and the surface where the threads meet. In mathematics, the pitch is equivalent to the length of 1 wavelength. The pitch of a screw shaft also relates to the diameter of the threads. In the following, the pitch of a screw is explained. It is important to note that the pitch of a screw is not a metric measurement. In the following, we will define the 2 terms and discuss how they relate to 1 another.
A screw’s pitch is not the same in all countries. The United Kingdom, Canada, and the United States have standardized screw threads according to the UN system. Therefore, there is a need to specify the pitch of a screw shaft when a screw is being manufactured. The standardization of pitch and diameter has also reduced the cost of screw manufacturing. Nevertheless, screw threads are still expensive. The United Kingdom, Canada, and the United States have introduced a system for the calculation of screw pitch.
The pitch of a lead screw is the same as that of a lead screw. The diameter is 0.25 inches and the circumference is 0.79 inches. When calculating the mechanical advantage of a screw, divide the diameter by its pitch. The larger the pitch, the more threads the screw has, increasing its critical speed and stiffness. The pitch of a screw shaft is also proportional to the number of starts in the shaft.

Helix angle

The helix angle of a screw shaft is the angle formed between the circumference of the cylinder and its helix. Both of these angles must be equal to 90 degrees. The larger the lead angle, the smaller the helix angle. Some reference materials refer to angle B as the helix angle. However, the actual angle is derived from calculating the screw geometry. Read on for more information. Listed below are some of the differences between helix angles and lead angles.
High helix screws have a long lead. This length reduces the number of effective turns of the screw. Because of this, fine pitch screws are usually used for small movements. A typical example is a 16-mm x 5-inch screw. Another example of a fine pitch screw is a 12x2mm screw. It is used for small moves. This type of screw has a lower lead angle than a high-helix screw.
A screw’s helix angle refers to the relative angle of the flight of the helix to the plane of the screw axis. While screw helix angles are not often altered from the standard square pitch, they can have an effect on processing. Changing the helix angle is more common in two-stage screws, special mixing screws, and metering screws. When a screw is designed for this function, it should be able to handle the materials it is made of.
screwshaft

Size

The diameter of a screw is its diameter, measured from the head to the shaft. Screw diameters are standardized by the American Society of Mechanical Engineers. The diameters of screws range from 3/50 inches to 16 inches, and more recently, fractions of an inch have been added. However, shaft diameters may vary depending on the job, so it is important to know the right size for the job. The size chart below shows the common sizes for screws.
Screws are generally referred to by their gauge, which is the major diameter. Screws with a major diameter less than a quarter of an inch are usually labeled as #0 to #14 and larger screws are labeled as sizes in fractions of an inch. There are also decimal equivalents of each screw size. These measurements will help you choose the correct size for your project. The screws with the smaller diameters were not tested.
In the previous section, we described the different shaft sizes and their specifications. These screw sizes are usually indicated by fractions of an inch, followed by a number of threads per inch. For example, a ten-inch screw has a shaft size of 2” with a thread pitch of 1/4″, and it has a diameter of 2 inches. This screw is welded to a two-inch Sch. 40 pipe. Alternatively, it can be welded to a 9-inch O.A.L. pipe.
screwshaft

Shape

Screws come in a wide variety of sizes and shapes, from the size of a quarter to the diameter of a U.S. quarter. Screws’ main function is to hold objects together and to translate torque into linear force. The shape of a screw shaft, if it is round, is the primary characteristic used to define its use. The following chart shows how the screw shaft differs from a quarter:
The shape of a screw shaft is determined by 2 features: its major diameter, or distance from the outer edge of the thread on 1 side to the inner smooth surface of the shaft. These are generally 2 to 16 millimeters in diameter. Screw shafts can have either a fully threaded shank or a half-threaded shank, with the latter providing better stability. Regardless of whether the screw shaft is round or domed, it is important to understand the different characteristics of a screw before attempting to install it into a project.
The screw shaft’s diameter is also important to its application. The ball circle diameter refers to the distance between the center of 2 opposite balls in contact with the grooves. The root diameter, on the other hand, refers to the distance between the bottommost grooves of the screw shaft. These are the 2 main measurements that define the screw’s overall size. Pitch and nominal diameter are important measurements for a screw’s performance in a particular application.

Lubrication

In most cases, lubrication of a screw shaft is accomplished with grease. Grease is made up of mineral or synthetic oil, thickening agent, and additives. The thickening agent can be a variety of different substances, including lithium, bentonite, aluminum, and barium complexes. A common classification for lubricating grease is NLGI Grade. While this may not be necessary when specifying the type of grease to use for a particular application, it is a useful qualitative measure.
When selecting a lubricant for a screw shaft, the operating temperature and the speed of the shaft determine the type of oil to use. Too much oil can result in heat buildup, while too little can lead to excessive wear and friction. The proper lubrication of a screw shaft directly affects the temperature rise of a ball screw, and the life of the assembly. To ensure the proper lubrication, follow the guidelines below.
Ideally, a low lubrication level is appropriate for medium-sized feed stuff factories. High lubrication level is appropriate for larger feed stuff factories. However, in low-speed applications, the lubrication level should be sufficiently high to ensure that the screws run freely. This is the only way to reduce friction and ensure the longest life possible. Lubrication of screw shafts is an important consideration for any screw.

China Best Sales Brush 12V Gear High Torque Low Rpm Price Worm DC Screw Motors   with Best SalesChina Best Sales Brush 12V Gear High Torque Low Rpm Price Worm DC Screw Motors   with Best Sales