Product Description

 

Product Description

OEM.ODM is available Greencate is acceptable for us 
We can design drawings according to your samples, or make samples according to your drawings.
We need more detail as follow with many thanks. This will allow us to give you an accurate quotation if you need customized.
• Product:
• Material:
• Class grade:
• Order Quantity:  
• Surface treatment:
• When do you need it by?
• Where to Shipping (Country with postal code please) :
• Measure: Inside Diameter/Outside Diameter/Thickness/Length:                
• Email your drawing ( jpg, png or pdf, word) with minimum 300 dpi resolution for good clarity.

Product Name	SPCIAL SCREW From DIN 7971
Material	SUS304
Color	polish,self-color
Standard	DIN GB ISO JIS BA ANSI
Finished	polish ,passivation

Detailed Photos

 

 

Product Parameters

 

Screw Thread					ST2.2	ST2.9	ST3.5	(ST3.9)	ST4.2	ST4.8	ST5.5	ST6.3
d
P		Pitch			0.8	1.1	1.3	1.3	1.4	1.6	1.8	1.8
a		max			0.8	1.1	1.3	1.3	1.4	1.6	1.8	1.8
dk		max=nominal size			4.2	5.6	6.9	7.5	8.2	9.5	10.8	12.5
		min			3.9	5.3	6.54	7.14	7.84	9.14	10.37	12.07
k		max=nominal size			1.35	1.75	2.1	2.25	2.45	2.8	3.2	3.65
		min			1.15	1.5	1.85	2	2.15	2.5	2.85	3.3
n		Nominal Size			0.6	0.8	1	1	1.2	1.2	1.6	1.6
		min			0.66	0.86	1.06	1.06	1.26	1.26	1.66	1.66
		max			0.8	1	1.2	1.2	1.51	1.51	1.91	1.91
t		min			0.55	0.75	0.95	1.05	1.15	1.35	1.55	1.8
		max			0.8	1	1.25	1.4	1.5	1.7	1.95	2.2
y		max	Type C		2	2.6	3.2	3.5	3.7	4.3	5	6
			Type F		1.6	2.1	2.5	2.7	2.8	3.2	3.6	3.6
Weight of per 1000 steel products(≈kg)					–	–	–	–	–	–	–	–

Packaging & Shipping

Installation Instructions

Certifications

Company Profile

ZheJiang Gentleman hardware Co., Ltd. always adhere to the principle of leading technology, quality first, customer first, and grow together with our partners around the world. Besides DIN standard products we supply also ex stock according to ISO, UNC, UNF, BSW (whit worth), BSF, ASTM and ANSI standards. Above all, our well known specialty is the delivery of deviating sizes and materials to sample or drawing. All Metal is known in the market as the specialist for special fasteners.
Hexagon head bolts and socket cap screws are also standard available in the higher grades 10.9 and 12.9. The plating company guarantees excellent finished products: electrolytic (blue, yellow or black passivized) and hot dip galvanizing are the most common standard surface treatments. But also e.g. The best surface treatment of Greencate may be applied.
Besides our focus on the machine and equipment construction we deliver to a great variety of industries like shipbuilding, petrochemical industry, furniture and electronically manufacturing. We can produce quickly in relatively small series for our Cooperation partner worldwide.
Our international trade company is located in ZheJiang city which is very close to the ZheJiang seaport and airport, can save a lot of transportation and time costs. And our Technical Engineer have 34 years’ experience in fasteners, these are how we keep superior quality and competitive offers for global valued customers.
We have good reputation in fasteners field with our long business customers because we always adhere to the principle of leading technology, quality first, customer first, and grow together with our partners around the world.
And i have been in the import and export industry for more than 15 years then can save costs from transportation, products, etc., while controlling product quality, so that you can achieve your company target.

FAQ

Q:Are you a manufacturing company or trading company? 
A: Our factory are specialized in manufacturing fasteners more than 40 years and our sales company have exporting experience for more than 16 years.

Q: Wonder if you accept small orders?
A: Do not worry. Please feel free to contact us, in order to give our clients more convenience, we accept small order.

Q: How can I get a sample to check your quality?
A: After price is confirmed, you can require samples to check our quality. Free for stock samples, but freight collect. For sample making, we will charge a sample fee. Sample fee will be confirmed according to the products’ craftwork.

Q: How can I customize my products? 
A: Attach your drawings with details. (Surface, treatment, material, quantity and special requirements etc.) . And we can print your logo according to your request and Brand Authorization Letter

Q: How long is your delivery time?
A: Generally it is 5-10 days if the goods are in stock. Or it is 15-20 days if the goods are not in stock, it is according to quantity.

Q: What is your payment term?
A: Payment=2000USD, 30%-70% T/T in advance (depending on different situations.), balance before shipment.

Q: What’s your packing?
A: Our Normal packing is bulking in Cartons, 20-25kgs/carton, 36cartons/ pallet. We also can pack products according to your requirement.

Q: Do you have after-sales service?
A: Certainly, you can contact us at any time. And we are very confident in our products, we pack them very well to make sure the goods in well protection to avoid any subsequent trouble regarding quality issue, we suggest you check the goods once you receive them. If there is any transport damaged or quality issue, don’t forget take the detail pictures and contact us as soon as possible, we will properly handle it to make sure your loss to reduce to the smallest. if it is our problem we will responsible for it.

Please feel free to contact us for detailed information.

Types of Screw Shafts

Screw shafts come in various types and sizes. These types include fully threaded, Lead, and Acme screws. Let’s explore these types in more detail. What type of screw shaft do you need? Which 1 is the best choice for your project? Here are some tips to choose the right screw:

Machined screw shaft

The screw shaft is a basic piece of machinery, but it can be further customized depending on the needs of the customer. Its features include high-precision threads and ridges. Machined screw shafts are generally manufactured using high-precision CNC machines or lathes. The types of screw shafts available vary in shape, size, and material. Different materials are suitable for different applications. This article will provide you with some examples of different types of screw shafts.
Ball screws are used for a variety of applications, including mounting machines, liquid crystal devices, measuring devices, and food and medical equipment. Various shapes are available, including miniature ball screws and nut brackets. They are also available without keyway. These components form a high-accuracy feed mechanism. Machined screw shafts are also available with various types of threaded ends for ease of assembly. The screw shaft is an integral part of linear motion systems.
When you need a machined screw shaft, you need to know the size of the threads. For smaller machine screws, you will need a mating part. For smaller screw sizes, the numbers will be denominated as industry Numeric Sizes. These denominations are not metric, but rather in mm, and they may not have a threads-per-inch designation. Similarly, larger machine screws will usually have threads that have a higher pitch than those with a lower pitch.
Another important feature of machine screws is that they have a thread on the entire shaft, unlike their normal counterparts. These machine screws have finer threads and are intended to be screwed into existing tapped holes using a nut. This means that these screws are generally stronger than other fasteners. They are usually used to hold together electronic components, industrial equipment, and engines. In addition to this, machine screws are usually made of a variety of materials.

Acme screw

An Acme screw is the most common type of threaded shaft available. It is available in a variety of materials including stainless steel and carbon steel. In many applications, it is used for large plates in crushing processes. ACME screws are self-locking and are ideal for applications requiring high clamping force and low friction. They also feature a variety of standard thread forms, including knurling and rolled worms.
Acme screws are available in a wide range of sizes, from 1/8″ to 6″. The diameter is measured from the outside of the screw to the bottom of the thread. The pitch is equal to the lead in a single start screw. The lead is equal to the pitch plus the number of starts. A screw of either type has a standard pitch and a lead. Acme screws are manufactured to be accurate and durable. They are also widely available in a wide range of materials and can be customized to fit your needs.
Another type of Acme screw is the ball screw. These have no back drive and are widely used in many applications. Aside from being lightweight, they are also able to move at faster speeds. A ball screw is similar to an Acme screw, but has a different shape. A ball screw is usually longer than an Acme screw. The ball screw is used for applications that require high linear speeds. An Acme screw is a common choice for many industries.
There are many factors that affect the speed and resolution of linear motion systems. For example, the nut position and the distance the screw travels can all affect the resolution. The total length of travel, the speed, and the duty cycle are all important. The lead size will affect the maximum linear speed and force output. If the screw is long, the greater the lead size, the higher the resolution. If the lead length is short, this may not be the most efficient option.

Lead screw

A lead screw is a threaded mechanical device. A lead screw consists of a cylindrical shaft, which includes a shallow thread portion and a tightly wound spring wire. This spring wire forms smooth, hard-spaced thread convolutions and provides wear-resistant engagement with the nut member. The wire’s leading and trailing ends are anchored to the shaft by means appropriate to the shaft’s composition. The screw is preferably made of stainless steel.
When selecting a lead screw, 1 should first determine its critical speed. The critical speed is the maximum rotations per minute based on the natural frequency of the screw. Excessive backlash will damage the lead screw. The maximum number of revolutions per minute depends on the screw’s minor diameter, length, assembly alignment, and end fixity. Ideally, the critical speed is 80% of its evaluated critical speed. A critical speed is not exceeded because excessive backlash would damage the lead screw and may be detrimental to the screw’s performance.
The PV curve defines the safe operating limits of a lead screw. This relationship describes the inverse relationship between contact surface pressure and sliding velocity. As the PV value increases, a lower rotation speed is required for heavier axial loads. Moreover, PV is affected by material and lubrication conditions. Besides, end fixity, which refers to the way the lead screw is supported, also affects its critical speed. Fixed-fixed and free end fixity are both possible.
Lead screws are widely used in industries and everyday appliances. In fact, they are used in robotics, lifting equipment, and industrial machinery. High-precision lead screws are widely used in the fields of engraving, fluid handling, data storage, and rapid prototyping. Moreover, they are also used in 3D printing and rapid prototyping. Lastly, lead screws are used in a wide range of applications, from measuring to assembly.

Fully threaded screw

A fully threaded screw shaft can be found in many applications. Threading is an important feature of screw systems and components. Screws with threaded shafts are often used to fix pieces of machinery together. Having fully threaded screw shafts ensures that screws can be installed without removing the nut or shaft. There are 2 major types of screw threads: coarse and fine. When it comes to coarse threads, UTS is the most common type, followed by BSP.
In the 1840s, a British engineer named Joseph Whitworth created a design that was widely used for screw threads. This design later became the British Standard Whitworth. This standard was used for screw threads in the United States during the 1840s and 1860s. But as screw threads evolved and international standards were established, this system remained largely unaltered. A new design proposed in 1864 by William Sellers improved upon Whitworth’s screw threads and simplified the pitch and surface finish.
Another reason for using fully threaded screws is their ability to reduce heat. When screw shafts are partially threaded, the bone grows up to the screw shaft and causes the cavity to be too narrow to remove it. Consequently, the screw is not capable of backing out. Therefore, fully threaded screws are the preferred choice for inter-fragmentary compression in children’s fractures. However, surgeons should know the potential complication when removing metalwork.
The full thread depth of a fully threaded screw is the distance at which a male thread can freely thread into the shaft. This dimension is typically 1 millimeter shy of the total depth of the drilled hole. This provides space for tap lead and chips. The full-thread depth also makes fully threaded screws ideal for axially-loaded connections. It is also suitable for retrofitting applications. For example, fully threaded screws are commonly used to connect 2 elements.

Ball screw

The basic static load rating of a ball screw is determined by the product of the maximum axial static load and the safety factor “s0”. This factor is determined by past experience in similar applications and should be selected according to the design requirements of the application. The basic static load rating is a good guideline for selecting a ball screw. There are several advantages to using a ball screw for a particular application. The following are some of the most common factors to consider when selecting a ball screw.
The critical speed limit of a ball screw is dependent on several factors. First of all, the critical speed depends on the mass, length and diameter of the shaft. Second, the deflection of the shaft and the type of end bearings determine the critical speed. Finally, the unsupported length is determined by the distance between the ball nut and end screw, which is also the distance between bearings. Generally, a ball screw with a diameter greater than 1.2 mm has a critical speed limit of 200 rpm.
The first step in manufacturing a high-quality ball screw is the choice of the right steel. While the steel used for manufacturing a ball screw has many advantages, its inherent quality is often compromised by microscopic inclusions. These microscopic inclusions may eventually lead to crack propagation, surface fatigue, and other problems. Fortunately, the technology used in steel production has advanced, making it possible to reduce the inclusion size to a minimum. However, higher-quality steels can be expensive. The best material for a ball screw is vacuum-degassed pure alloy steel.
The lead of a ball screw shaft is also an important factor to consider. The lead is the linear distance between the ball and the screw shaft. The lead can increase the amount of space between the balls and the screws. In turn, the lead increases the speed of a screw. If the lead of a ball screw is increased, it may increase its accuracy. If not, the lead of a ball screw can be improved through preloading, lubrication, and better mounting accuracy.