Technology for the production of screws and self-tapping screws. Technology for the production of screws and screws Technology for the production of screws and the necessary equipment

Despite economic crisis The construction market is experiencing stable growth. Residents of our country are constantly building or repairing something, so fastening materials are used very popular. Beginning entrepreneurs who want to start the production of self-tapping screws as a business can be sure that such an activity will generate high income.

Registration of activities

To open the production of self-tapping screws in Russia, you must first formalize everything Required documents. If you are planning to create large enterprise, which will produce a wide range of products in large volumes, should register an LLC. This will allow you to sell products by bank transfer. legal entities, as well as enter into agreements with suppliers of raw materials.

This type of activity is not licensed, so you will not have to obtain any permits. To make your products competitive, it is advisable to undergo certification. For mini-production of self-tapping screws, it is enough to register as an individual entrepreneur.

Premises and location

The success of a business largely depends on the location where it is located. Some companies are more attractive to potential buyers because they are easy to reach. But not in our case.

You should not rent a building in the city center for a self-tapping screw production plant. After all, these are not buns that passers-by buy. Such products are purchased in tons, so sales volumes do not depend on where your enterprise is located - in the center or on the outskirts. The most important thing is that there are good access roads leading to it. The buyer will pick up quality goods at an affordable price from anywhere, so when choosing a premises, be guided by the rental price.

Choose an inexpensive, convenient room that meets all requirements. This could be a former garage for tractors or other special equipment. For it you will pay approximately 5 thousand per month. Agree that this is ridiculous money for a business, even a small one. Remove all the trash from there, install electricity and you can start choosing a production line.

Equipment

In order for the product to be of high quality, you need to purchase machines for the production of self-tapping screws. Such equipment is offered by different manufacturers. The choice of certain models largely depends on the self-tapping screw production technology that you are going to use in your enterprise.

Scheme: production of self-tapping screws

The technological process includes the following stages:

• Manufacturing of blanks;
• Thread cutting;
• To expand the product range, units for surface hardening and anti-corrosion treatment should be added to the line for the production of self-tapping screws.

The basic set of equipment for the production of self-tapping screws consists of the following units:

• Drawing machine;
• Unit for forming a workpiece;
• Thread cutting machine.

If you are going to compete with the big ones industrial enterprises, to improve the quality of products, you should purchase an electroplating line, a drying centrifuge and a hardening furnace.

The cost of equipment varies over a wide price range. There is no point in buying an expensive high-performance line until all sales issues have been resolved. If you are limited in financial possibilities, you can purchase used equipment.

You will have to spend a lot of money to equip your enterprise, since all the machines are quite expensive. High-performance equipment pays for itself much faster. This should be taken into account when developing a business plan.

Technological process

A self-tapping screw is a fastener consisting of a rod with an external thread and a head. It is worth noting that the technology and equipment for the production of nails and self-tapping screws are almost the same, but there are still some differences.

The production process consists of the following stages:

• Wire cutting to size;
• Applying threads and forming a cap;
• Hardening process;
• Washing;
• Anti-corrosion treatment.

Low-carbon wire that has undergone heat treatment is used as a raw material for the manufacture of self-tapping screws. If you are interested in the production of self-tapping screws, a video on this topic can be found in this article.

Staff

Because the Production Line It works automatically and does not require many workers to service it. Operators oversee pre-set equipment, supply supplies, and remove finished products. When drawing up a business plan for the production of self-tapping screws, at the first stage you can provide two workers. In addition to the salary of 15–20 thousand rubles, the costs of their training should be taken into account. You also need to hire an accountant. The salary of such a specialist is in the range of 25–30 thousand rubles.

Business plan

To be profitable, you should not miss the following important points:

• Purchase of equipment;
• Selection of premises;
• Purchase of raw materials;
• Choice of assortment;
• Hiring employees;
• Search for sales markets.

Before you start work, prepare all the necessary documents.

Income and expenses

• Rental of premises – 5 thousand rubles;
• Salary – 40 thousand rubles;
• Raw materials – 15 thousand rubles;
• Electricity bills – 10 thousand rubles.

Profit must be calculated based on the lowest market price - 20 kopecks apiece. The line produces 50 products in 1 minute, that is, in one work shift their number reaches 72 thousand pieces. The company generates a profit of 14.4 thousand rubles per day, and 432 thousand rubles per month. Subtract all current expenses and get 350 thousand rubles. All initial investments can be returned in just a few months.

Raw materials

As a rule, there are no problems with the purchase of raw materials. Suppliers offer blanks or wire in reels at affordable prices. They typically deliver the raw materials directly to the facility, allowing you to save on shipping costs. The choice of raw materials largely depends on technology and equipment.

To reduce the cost of products, you can purchase raw materials directly from manufacturers at low wholesale prices. Steel or brass wire costs approximately 12.5 thousand rubles per 1 ton. One reel will yield 500 thousand self-tapping screws.

Range

In order for your business to generate high income, you need to constantly expand your product range. It will not be possible to achieve much variety, since self-tapping screws can differ only in the type of head, length and thread.

Produce different fastener models in small quantities. Over time, you will be able to decide which screws are in demand in your region.

Production of self-tapping screws Production of self-tapping screws

Sales of products

To receive a stable monthly income, you need to find potential buyers. Sales of fasteners must be continuous. To achieve this, you need to produce a wide range of products. This could be the production of roofing screws, nails, anchors, etc. Focus on the most popular types of products. In the future, you can adjust your business depending on the season.

Most the best option- these are agreements for the supply of products with. For large-scale construction, large volumes of such products are purchased. Sometimes one object covers the monthly productivity of the enterprise. Also, pay attention to . For example, a small furniture workshop consumes several tens of thousands of screws per month.

First of all, try to establish contacts with construction supermarkets, which will be happy to expand their range. In any city there are markets or markets, where you should start. To conclude contracts for large deliveries, you will have to work hard. To attract customers, you will have to slightly reduce product prices.

Conclusion

Now you know how to make self-tapping screws and make money from it. It's simple, promising and sufficient profitable business. Since all the equipment is automated, the main problems can arise only with the sale of products. But they are easily solved in the process of work. Read about others on our website.

To register the production of self-tapping screws as a business, just open an IP. Corresponding Code OKVED: 25.94.– “Production of fasteners.”

No special licenses required. Important requirement - raw materials must comply with GOST. The following GOSTs have been developed for finished products: 11652-80 – “Self-tapping screw”, 10619-80, 10618-80, 10620-80, 10621-80, 11651-80. Different types of screws have their own requirements and standards.

Advantages of the enterprise

Why is it profitable to organize the production of self-tapping screws:

• Long product shelf life. It can be stored for years, and in the absence good sales at the start, you will not lose money on spoiled goods. The main thing is to ensure dryness in the area allocated for storage;
• Wholesale sales. Such products are purchased exclusively in bulk, so there is no need to work with small and retail buyers;
• Stability. In this niche there is no concept of “promotion” of a brand or fierce price competition. As a rule, goods buyers cooperate with one plant for years. For getting stable income it is required to establish sales in 2-3 places;
• Low cost of setting up a workshop. Despite the expensive industrial equipment, the workshop itself does not require huge investments. It is enough to find cheap premises on the outskirts of the city;
• No special requirements for personnel qualifications. All machines are easy to operate and maintain; any worker can be taught to use them in a few days. There is no need to hire professionals and pay above-average salaries.

Room

Total building area for the plant – 70 square meters . The workshop and machines will occupy 45 square meters. m, warehouse and utility rooms– 25 sq. m.

Choose a place outside the city, this will make it easier to obtain raw materials and export finished products by truck, plus rental costs on the outskirts are low. Such space will cost $400-450 per month. Repairs will cost approximately $1000.

Requirements for production premises

1. Electrical network 380 V;
2. Availability of cold water, sewerage;
3. Ceilings from three meters;
4. Availability of access roads to the plant;
5. Shower and toilet for workers.

Self-tapping screw production technology

At the factory, production takes place using the cold stamping method.

Main stages

The raw material goes through several processing stages before it becomes the finished product:

• Formation of a workpiece, or blank, using a cold heading machine. On at this stage the product acquires the required length, tip, head;
• Rod threads are cut on a thread rolling machine.

To improve product quality surface hardening processes can be added to increase the strength of the product and anti-corrosion treatment. After this, the goods are packaged. Packaging is common plastic bags 250, 500 and 1000 pieces each.

Range

A good self-tapping machine can produce several types of screws, differing in characteristics such as length, thread and type of head.

To increase demand, it is worth choosing several types: for example, universal, roofing, for different materials (metal, plasterboard, wood), screws are in demand for sandwich panels and window profiles.

The best equipment for the production of self-tapping screws

The minimum configuration of the plant consists of the following machines:

1. Drawing. The metal wire enters the furnace, where it is pulled through several dies to form semi-finished products of the required size;
2. Cold heading;
3. Thread rolling;
4. Thermal hardening oven for added strength.

It makes no sense to buy each machine for the production of self-tapping screws separately; it is better to purchase a complete line.

The average price of a “set” is 20 thousand dollars. This is the cost of equipment that produces approximately 60 units per minute. When working in two shifts per month, 1.8-2 million pieces can be produced. Expensive Japanese machines are capable of forming up to 300 pieces per minute, but it makes sense to buy them only if there are large pre-orders.

A high-quality and inexpensive self-tapping screw production line is offered Taiwanese companies LianTeng and FOB, good machines Sold by Odessa company Cupra. The cost of European equipment is from 30 thousand dollars.

Associated costs: boxes for storing finished products, small tools (gloves, buckets, shovels, etc.) - around $100.

Raw materials for making self-tapping screws

The best raw material for manufacturing by cold stamping is wire made of steel (stainless, high-carbon) or brass. Usually consumables It is bought in the form of reels with winding, less often - in the form of already cut blanks of the required length. The best grades of steel wire are ST 08 KP and ST 10 KP.

Material cost– around $600-700 per ton. About 500 thousand units of goods are made from one such reel. You will need 3-4 tons of wire per month total cost up to $3000.

Staff

For a quick return on investment, it is necessary to organize the work of the workshop in two shifts: two workers each. Invite a freelance specialist to do the accounting. At first, you should take on the functions of a manager.

Together with the cleaning lady, there are five full-time employees. Salary fund – about $2000 per month.

Sales of goods

The finished product is best offered to companies involved in repair and construction, furniture factories, large stores of building materials and fastening devices.

These are enterprises that purchase large wholesale quantities. It is unprofitable to work with small orders (less than 100 thousand units).

Costs and profits

You need a detailed calculation of costs and future profits.

Capital investments in business

• Registration procedure – up to $40;
• Rent of premises for three months + repairs – $2300;
• Purchase and installation of equipment – ​​$21,000;
• Purchase of raw materials for the first month – $3,000.

Total - about $26,000.

Monthly costs

1. Rent – ​​$450;
2. Steel wire – $3000;
3. Salary – $2000;
4. Utilities and logistics costs – $300.

Total – approximately $5700.

By producing 1.7-2 million screws per month at a wholesale price of $4.6-5 per thousand pieces, we get revenue in the region of $8500-9000. Net monthly profit– approximately $3000.

Production of self-tapping screws as a business. A huge plus is the opportunity to scale the business, purchase additional equipment and work with larger customers.

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A self-tapping screw is a product designed for fastening wooden and metal parts. The line for the production of self-tapping screws produces at the output a product with a thread of a special triangular shape, which itself forms a hole. If such fasteners are used, then there is no need for additional tools. By purchasing lines for the production of self-tapping screws and opening an enterprise, you can get a promising and stable business.

Business

IN Russian Federation this product It is manufactured not only for personal needs, but is imported to other countries. However, domestic demand is only 70% satisfied. Mechanical engineering in this area will continue to develop. The self-tapping screw is a universal fastener that has a fairly stable demand.

Experts characterize this business as profitable at 55%. To start it, you need a line for the production of self-tapping screws, the price of which is about 650 thousand rubles. The power of equipment in this price range is enough to produce two million products per month.

The markup can be as high as 95%, because the annual turnover of a small plant, as a rule, is approximately 5 million rubles.

Production technology

The raw materials usually used are stainless or carbon steel, as well as brass. As a rule, this raw material is represented by special cut round timber or wire coil. Suppliers of these materials are easy to find. Russia produces a sufficient amount of rolled metal. Therefore, it is possible to choose a plant that is geographically located closer to the workshop.

To understand what type of self-tapping screw production line you need to purchase, you need to consider the production process of this product in stages. This technology is called cold stamping.

Stage 1	It is necessary to stretch the steel wire rod. Operations take place on drawing machines. The basis is rows of dies of different diameters. The metal rod that passes through them gradually decreases in diameter. The equipment is equipped with a cooling system.
Stage 2	Cut the workpieces to the specified length. Forming caps on cold heading machines.
Stage 3	The workpiece is transported to the thread rolling installation. To do this, you need to use a special conveyor. They come with workpiece grips.
Stage 4	The product is delivered to the furnace, where hardening occurs at a temperature of 930 degrees. After this, the temperature progressively decreases. This must be done to uniformly remove the tension plane of the metal. Next, the self-tapping screw enters the washing line.
Stage 5	Galvanic coating is required. A small number of baths are used for this. They prepare surfaces and directly apply anti-corrosion layers. A zinc anode is installed in the final bath.
Stage 6	Drying occurs in a special centrifuge. This is the penultimate stage of the industrial process.
Stage 7	The final stage is product quality control and packaging.

As practice shows, there is a lot of equipment for production. It is unrealistic to buy one installation for making self-tapping screws. This is a whole big one technological line. Today, almost all processes in the lines are automated. Control of such equipment is possible by one operator.

Equipment

In today's market, dealers offer lines made in Taiwan. The leaders are the LianTeng and FOB brands. The line consists of several devices. Thanks to them, you can control the production processes at each stage. You can combine techniques freely. The manufacturer of Taiwanese self-tapping screws notes that this technique is quite reliable. It almost never fails if used correctly and skillfully.
Equipment for the production of screws brand FOB: Taiwan

The line for the production of Taiwan self-tapping screws, the price of which depends on the speed of production of products, makes it possible to produce 55 self-tapping screws per minute. The most expensive installation can produce 255 pieces of finished screws per minute. The cost of the line is approximately $2,000.

Also, the price of the line depends on the assortment produced on it. The range is determined by the length of the workpiece and the thread pitch. The more customization options a device allows, the more expensive it is. There is equipment that, after resetting the settings, allows you to make a screw, screw and dowel. If in the future manufacturers plan to increase production volume and the list of finished products, then it is necessary to purchase modifications. For the future, it is best to buy new equipment. Used equipment may fail.

Four of the best brands of self-tapping screw production lines:

KONNAR

ID5 X 85 in conjunction with ID6 X 130 INNOR

YН2076 FOB

YН1564 LianTeng

Price YН2076 FOB – 23,000 USD, Z12-5 Сandid – 14,00 USD In a minute, these two brands are capable of producing 125–165 pieces of products, respectively.

Equipment for the production of Z12-5 Сandid self-tapping screws

Product quality matches Russian standards. You can buy a line for the production of self-tapping screws in Taiwanese representative offices, while recouping the investment in a relatively short period of time. Of course, this will be possible in conditions of full sales of manufactured products.

There are also European brands of this equipment. But their price is 3–4 times higher than their Taiwanese counterparts. You can also pay attention to Chinese equipment. Their performance and quality, as well as other special features, are not compromised by Taiwanese brands. The cost of Chinese equipment is approximately the same. As one of the options, you can consider Ukrainian-made equipment. Cold heading equipment ABO 215 is capable of producing 165 products in one minute. The price of this equipment is about 16,000 US dollars. The quality is no worse than Chinese and Taiwanese equipment.

Video: Thread rolling machine

Self-tapping screw- view fastener, which allows, when connecting different parts, to cut a thread in one of them. It is very convenient when working with wooden, polymer and metal materials due to skipping the intermediate operation - drilling holes for the connecting element.

They have found wide application in construction industry; used in the manufacture household appliances; used in mechanical engineering.

Opening a business for the production of self-tapping screws is quite profitable today.

To do this you need to go through several steps:

• become familiar with the production technology of self-tapping screws;
• study machines and production lines;
• draw up a business plan.

Self-tapping screw production technology

The technological chain for the production of self-tapping screws consists of several key segments:

1. The raw material, usually wire of a certain diameter, is fed to an automatic machine, where the intermediate semi-finished product is formed: cutting to the required length occurs; then, through the cold heading process, the head of the future self-tapping screw is pressed.
2. The workpieces enter the machine along the conveyor, where vibration grippers are used to form threads in the next machine.
3. Almost finished self-tapping screw undergoes heat treatment followed by washing.
4. The next stage is chemical treatment, for the purpose of applying anti-corrosion coatings.
5. The final treatment is drying.
6. The technological chain ends quality control and packaging.

From the description of the production technology, it becomes clear that the production of products requires several different stages, respectively, different machines and equipment.

Machine tools and equipment for self-tapping products

At the core of the process, the production of self-tapping screws is carried out on a small production line. It includes:

1. Cold heading equipment. Conventionally, it is divided into two groups: with a semi-protective casing and a protective casing. They differ in productivity, control system, automation, and product range. The simplest models are focused on the production of one type of product.
   More expensive machines allow you to expand the range to the production of screws, screws and other types of hardware. The productivity of the machines, on average, is in the range of 40…250 pcs/min. Naturally, prices between simple models and high-performance ones differ several times. Some models can additionally form a drill on the tip of the self-tapping screw.
2. Thread rolling machine. Provides thread rolling using a flat replaceable die. It has the ability, depending on the model, to vary the thread pitch.
3. Thermal hardening furnace. Gives the self-tapping screw a surface strength on the Brinell scale of at least 55 units. The heating process to a temperature of approximately 1000 degrees Celsius lasts about one minute, followed by cooling (tempering) in a special quenching environment.
4. Galvanic line. Designed to form an anti-corrosion coating on the surface of the self-tapping screw. This can be oxidation, phosphating and zinc coating. It consists of several baths where electrochemical reactions for coating are carried out.
5. Centrifuge. Dries ready-made self-tapping screws with hot air after washing them to remove residual chemical solutions during the galvanizing process.

Purchasing one element from the entire production line makes sense if it is to replace completely broken equipment or to replace it with a more advanced device.

To begin a full cycle for the production of self-tapping screws, economic calculations should be made for the entire technological chain.

There are several manufacturers from Europe, China and Taiwan on the market. If we compare the technical parameters, then the most cost-effective would be to purchase a production line in Taiwan. You can combine and create a line of machines from different manufacturers.

For example, you can integrate into the equipment installation process a cold heading machine made in Ukraine (Odessa). The rest of the machines are made in Taiwan or China.

Before starting any business, it is necessary to work out the economic component of the production process. A preliminary analysis of the possible profitability or loss of the project is described in the business plan.

Business plan for analyzing the production of self-tapping screws

In that theoretical project An analysis of all operations is carried out, from the supply of raw materials, the purchase of equipment for production and ending with the sale of products.

Main components of a business plan

The very first step What needs to be done is to conduct market research on the demand for the products that are supposed to be produced. This is revealed by needs analysis retail chains, markets and production: construction organizations, mechanical engineering and furniture enterprises. The data is recorded and will be needed for further calculations of production profitability.

Advice: when studying the self-tapping screws market, it is useful to determine how much is represented by domestic products and how much is imported.

Second step– identify the most requested positions. This will determine where to start manufacturing process: purchase machines from narrow specialization for assortment filling or install a full-fledged production line.

It may turn out that at first it is more profitable to put production on a small assortment. As development progresses, gradually improve and increase production capacity through the acquisition of more advanced machines.

Example:

1. when installing drywall on a metal profile, the most used one is a sharp oxidized metal self-tapping screw 25 mm long;
2. For fastening plywood, the most commonly used are sharp oxidized self-tapping screws with a length of 45...55 mm.

The next step – choosing a location for future production.

There are a number of requirements for the location of the future mini-workshop:

• availability of access roads, minimum - gravel road;
• provision of power grid, — the power consumption of a production line can reach several tens of kilowatts;
• sewerage and water supply systems must be connected to the site;
• it is necessary to place a production line on the total area of ​​the territory with convenient access to all machines; travel routes must ensure free supply and return transportation of raw materials and finished products, respectively.

From the above it follows that optimal solution— this will be the rental of space in idle production workshops, workshops.

Preliminary data on rent and costs for energy, water, and heat supply also need to be recorded on paper.

Selection of the product range to be produced.

The product range that is produced affects the rate of return on investment for the project:

• the wider the range of hardware products is presented, the more potential consumers of industrial products there will be, and accordingly, the turnover of capital will accelerate;
• a wider product range automatically presupposes the availability of productive machines, but with higher costs for their acquisition.

Note: the size of the range of future products and, therefore, the required production line are interconnected with the demand for hardware.

1. An important but necessary part of the costs is wage to the staff. In production, as a rule, a piecework-bonus system of material remuneration is adopted - in other words: “the more you did, the more you received.”

Tip #1: at the stage of production growth, for the first six months it is better to use a fixed tariff schedule, with a gradual transition to more progressive payment methods.

Tip #2: It is not advisable to skimp on the qualifications of workers. Due to my experience, professional master will be able to complete the job faster and with better quality.

Economic calculations for raw materials

The cost of the source material is an important component in the final price of the screw. But cheap doesn’t always mean good.

1. Firstly: the price of raw materials must take into account transport costs for delivery to the place of production.
2. Secondly: good quality metal cannot differ greatly from the average market price.

If this is the case, then the metal either does not meet the requirements of GOST, or the question arises about the origin of the product.

Note: with far-reaching plans, it is better to focus on reliable and proven suppliers who can ensure the rhythm of deliveries, and, in the future successful work, will be able to provide various deferments in payment for original products.

It is necessary to consider the issue in a separate paragraph product sales. Without establishing sustainable sales, the idea of ​​organizing the production of self-tapping screws is doomed to failure.

Potential consumers of hardware products:

• construction organizations, including small teams for finishing work;
• enterprises producing household appliances;
• furniture workshops, up to private small workshops;
• manufacturing enterprises associated with the production of construction and finishing materials;
• markets with construction assortment;
• trade organizations, both large (wholesale) and small stores.

The most likely and convenient for cooperation will be large and medium-sized construction, industrial and furniture organizations, as well as wholesalers. trading enterprises and large hardware stores.

Advantages of working with them:

• work is carried out under long-term contracts;
• the opportunity to receive advance payment for the release of future products;
• constant source of sales;

Work with small enterprises at the stage of production formation should be based only on the principle of advance payment.

Implementation and deferment of payment are unprofitable for several reasons: big revenue small organizations will not bring it, but in case of delays in payments, a significant amount of time will be spent on collecting debts than on engaging in their main production.

Basic costs, one-time and ongoing

For intermediate calculations and the final preparation of a business plan in the financial analysis The following expenses are taken into account:

• the cost of the main and auxiliary equipment taking into account delivery, installation and connection;
• rent of premises for each month;
• costs for electricity and water supply for one calendar month;
• employee salaries;
• overhead costs for chemicals, lubricants;
• tax deductions;
• monthly costs for raw materials;
• registration with all fiscal authorities to start activities;
• payment of bank interest;
• overhead costs (range from 5...25% of monthly operating expenses).

By reducing all these numbers to the given monthly expenses, we can estimate the approximate weighted average volume of output.

For such calculations, it is necessary to focus on 25...100 types of product range and a selling price that is 10...15% lower than expected, according to preliminary agreements with clients.

The data obtained is the minimum profitability of production. It will grow as sales increase, and accordingly, production increases and production costs decrease.

Specific cost figures are not given deliberately - each region has its own starting opportunities for organizing a business.

With a thoughtful approach, thorough market analysis, and good organization of production, the payback period today will be from 1 to 3 years.

When we talk about a screw, does everyone know what it is? The word screw comes from the German Schraube. In fact, it is a screw that can easily be screwed into any soft material, forming a thread there “on its own.” A typical material of this kind is wood.

Why is a screw able to be screwed into soft materials? First of all, due to the threads, which cover a significant part of the screw shaft. This thread is different from the threads found on screws and bolts. It is not surprising, since the latter are screwed not into wood, but into metal. The thread on the screw is slightly higher. It has a significant cutting pitch and is applied to the threaded section of the screw in the form of a conical shape, which tapers towards the end of the screw. By the way, the thread on a screw can be cut either along its entire length or only along its part.

Since the sizes of screws are quite varied, a natural question arises on what this depends on. The sizes of screws closely correlate with their purpose. So for attaching nameplates to already finished products A very small screw, popularly called a “bug”, is widely used. Its dimensions: diameter - 4 mm, length - 8 mm. Another screw, called a travel screw, has a length of 170 mm and a diameter of 24 mm. And this is understandable, since it is used to attach the railway rail to the sleepers. The heads of such screws also have different shape, determined by the installation conditions themselves, appearance products and the requirements that apply to the mounted structure.

The head shapes are shown in Fig. 1.

About the types of heads and slots of screws

Among the types of heads we highlight: countersunk, countersunk double, countersunk truncated, countersunk "horn" type, semicircular head, semicircular head with a press washer, narrow cylindrical head, trapezoidal head, hexagonal head, hexagonal head with a press washer.

The countersunk head is recessed in the material of the element being fixed. At the same time, the surface of the material was and remains smooth. The countersunk double head is a reinforced version of the countersunk head. It is able to withstand significant loads, even with the impact method of installation in solid materials.

Countersunk truncated head makes it possible to press the element being fixed to the base material with high efficiency. This is achieved due to the fact that the length of the thread of the fastening element is increased; a lower platform is formed on the head, which is perpendicular to the action of the pullout load.

Concealed horn type head remarkable in that it very effectively ensures high-quality pressing of drywall to the base material. It is the specially curved shape of the head, which has the appearance of a “horn,” that ensures optimal perception of the pullout load. The semicircular head, thanks to the wide bearing surface, effectively holds the element being fixed. The use of such a head is justified when there is no particular need to keep the surface of the element being fixed flat.

Another type of head - with a press washer - represents an increased bearing surface of the head and a reduced height. Due to the expanded bearing surface, a head of this type is ideal for reliably fastening sheet materials.

Narrow cylindrical head provides an important, in some cases, minimum load-bearing surface. During installation, this ensures that it is completely recessed into the element being fixed. It is widely used in fastening elements that are fixed both in the base material and in the element being fastened using threads that perform the main function of fastening. The trapezoidal head has an increased bearing surface, and locking notches are located on its inner side.

One of the most famous and oldest types of fastener heads is hex head. As a rule, it is standardized to fit the existing key sizes, and in order to install it using a power tool, special hexagonal sockets are used.

The functions of a hex head with a press washer are the same as those of a simple hex head, but its bearing surface is still larger.

In order to mount a screw using tools, using a screwdriver or a hexagon, slots are pre-formed in the screw head, which can be straight, cross-shaped, combined, in the form of a six-pointed star, in the form of a hexagon or in the form of an internal hexagon.

Traditionally, for the manufacture of screws, a material such as ST 08 KP or ST 10 KP steel is used.

Screw manufacturing technology

At the first stage of the manufacturing process, a blank or base for the screw is formed. In this case, a device similar to a nailer is used everywhere. Thanks to this device, the screw head and its tip are formed. The diameter of the future screw is determined by the wire used.

At the second stage of manufacturing a screw, threads are cut on its shaft. And this process is carried out using special machines. In this case, the blanks of future screws are poured into a hopper, where, thanks to a vibrating conveyor and an anchor mechanism, they arrive one by one into the area where thread cutting is carried out. At the same time, the screw blanks are strictly oriented in relation to the working elements, i.e. to flat dies, moved towards and parallel to each other, and perpendicular to the axis of the screw, which are pressed tightly against the screw shaft. At the same time, depending on where they are manufactured, dies are produced based on the basic parameters of the thread.

This scheme makes it possible to produce screws with a diameter of 10-12 mm, but screws with larger diameters are usually produced using the hot stamping method. An example of such a product is a travel screw, the dimensions of which we talked about just above.

Self-tapping screw manufacturing technology

As you know, the self-tapping screw has this name because it is capable of cutting threads anywhere, in wood, plastic, metal and concrete, etc. This is due to the fact that its surface has powerful strength, obtained using heat treatment, i.e. hardening The end of the self-tapping screw is often made in the form of a drill. Thus, its optimal screwing into the structures being fastened is achieved, as well as drilling a hole of the required diameter.

At the first stage During manufacturing, the formation of a drill is ensured even during the process of forming the blank.

At the second stage, similar to the thread formed on a screw, the formation of a self-tapping thread is ensured.

At the third stage The finished self-tapping screw is surface hardened. This is perhaps the most important stage in the manufacture of self-tapping screws, since it is important to strictly adhere to all technological methods to ensure that the required technical parameters are obtained.

At the fourth, final stage, self-tapping screws are protected from possible corrosion using methods such as phosphating, oxidation, galvanizing with yellow or white zinc.