The use of blind rivets in construction
Blind rivets today are widely used in construction. First of all, this type of fastener is often used in systems of so-called ventilated facades. Such an element is usually used: to connect the parts of the system to each other; to fasten facing materials to the system; when installing window adjunctions (drains, slopes); when installing additional items.The use of such systems is strictly regulated by the State Construction Committee of the Russian Federation and other regulatory organizations. Individual elements of the systems also have the necessary regulatory and permitting documents. However, until recently, information on regulatory documents and requirements for the quality characteristics of rivets was extremely scarce. The lack of necessary information did not allow regulating and controlling the use of rivets. Since there are both high-quality products of well-known manufacturers and cheap low-quality products on the market, the lack of regulatory documents and control based on them allows you to “save” by using obviously unsuitable solutions. This practice of "savings" is a widespread phenomenon among unscrupulous participants in the facade systems market. At the same time, without the necessary information, a conscientious participant in the facade market finds it difficult to make the right decision on the use of one or another type of rivet. A number of leading Russian developers of facade systems and sellers of foreign facade systems, as well as large design and installation firms, are interested in the availability of information and regulatory documents that allow them to control the quality when using their systems and to weed out unscrupulous bidders who win the tender at any cost, and then indulge in all serious for the sake of saving.What is needed in order to decide which rivets to buy and what is a confirmation of their quality?
1.Certificates of conformity according to the GOST-R system.
Unfortunately, the presence of a certificate of conformity according to the GOST-R system is not a guarantee of quality, regardless of whether it is issued for a batch, contract or mass production. The certificate is often issued for compliance with GOST 10304-80, which is GOST for driven rivets, i.e. completely different products, the technical characteristics of which have nothing to do with the fasteners used in facades.
2. Certificate of ISO quality control system (ISO 9001:2000) of the manufacturing factory.
This is a serious argument showing that a product supplier is working with a quality product manufacturer. In 99% of cases, sellers of cheap products will not only not show you the ISO certificate of the manufacturing factory, but will not tell you where it was produced. You will not find this information on the packaging. However, the ISO quality system certificate gives general information about the level of the manufacturer, but not about which rivets to use for a particular technical solution.
To resolve this issue, it is necessary to know the quality / technical characteristics that rivets must comply with and the conditions for their use.
What do you need to know?
1. The material from which the rivets are made.
2. Compatibility of fastened materials and rivet materials.
3. Strength characteristics.
Depending on the material of the rivet:
- strength characteristics;
- corrosion resistance of the rivet and the materials connected to it.
The name of the rivet indicates the material of the body of the rivet and its core. It may or may not be the same. The most common types of rivets in construction with the following combination of materials:
• aluminum (AlMg2.5%) / aluminum (AlMg5%);
• aluminum (AlMg3.5%) / steel;
• aluminum (AlMg3.5%) / stainless steel;
• steel / steel;
• stainless steel / stainless steel.
The first place in the designation is the material of the rivet body (the part of the rivet that remains in the joint and plays a load-bearing role). In second place is the designation of the rivet shaft, the remainder of which after installation does not affect the strength characteristics, but plays a role in the issue of corrosion.
The most resistant to corrosion is stainless steel rivet. Aluminum comes next in terms of reliability, followed by steel. It may be objected that steel rivets are zinc coated. In this regard, we should recall the studies carried out earlier for facade systems with an air gap (the so-called "ventilated facades"), which showed that in an urban environment the thickness of the zinc coating decreases by 5-7 microns per year. Steel rivets have an average zinc coating thickness of 7 microns. That is, after 1 year we have a steel rivet that is not protected by anything and is actively destroyed by corrosion.
A special place is occupied by the aluminum / steel rivet, because it is the most common because of its low cost and ease of riveting. Until recently, it was simply called "aluminum". At the same time, under this name, both high-quality products made of AlMg3.5% alloy, which are used by European manufacturers, and products made of cheap AlMg1% alloy, manufactured in China and Taiwan and supplied to the market directly to the market, are sold under this name.
1.Certificates of conformity according to the GOST-R system.
Unfortunately, the presence of a certificate of conformity according to the GOST-R system is not a guarantee of quality, regardless of whether it is issued for a batch, contract or mass production. The certificate is often issued for compliance with GOST 10304-80, which is GOST for driven rivets, i.e. completely different products, the technical characteristics of which have nothing to do with the fasteners used in facades.
2. Certificate of ISO quality control system (ISO 9001:2000) of the manufacturing factory.
This is a serious argument showing that a product supplier is working with a quality product manufacturer. In 99% of cases, sellers of cheap products will not only not show you the ISO certificate of the manufacturing factory, but will not tell you where it was produced. You will not find this information on the packaging. However, the ISO quality system certificate gives general information about the level of the manufacturer, but not about which rivets to use for a particular technical solution.
To resolve this issue, it is necessary to know the quality / technical characteristics that rivets must comply with and the conditions for their use.
What do you need to know?
1. The material from which the rivets are made.
2. Compatibility of fastened materials and rivet materials.
3. Strength characteristics.
Depending on the material of the rivet:
- strength characteristics;
- corrosion resistance of the rivet and the materials connected to it.
The name of the rivet indicates the material of the body of the rivet and its core. It may or may not be the same. The most common types of rivets in construction with the following combination of materials:
• aluminum (AlMg2.5%) / aluminum (AlMg5%);
• aluminum (AlMg3.5%) / steel;
• aluminum (AlMg3.5%) / stainless steel;
• steel / steel;
• stainless steel / stainless steel.
The first place in the designation is the material of the rivet body (the part of the rivet that remains in the joint and plays a load-bearing role). In second place is the designation of the rivet shaft, the remainder of which after installation does not affect the strength characteristics, but plays a role in the issue of corrosion.
The most resistant to corrosion is stainless steel rivet. Aluminum comes next in terms of reliability, followed by steel. It may be objected that steel rivets are zinc coated. In this regard, we should recall the studies carried out earlier for facade systems with an air gap (the so-called "ventilated facades"), which showed that in an urban environment the thickness of the zinc coating decreases by 5-7 microns per year. Steel rivets have an average zinc coating thickness of 7 microns. That is, after 1 year we have a steel rivet that is not protected by anything and is actively destroyed by corrosion.
A special place is occupied by the aluminum / steel rivet, because it is the most common because of its low cost and ease of riveting. Until recently, it was simply called "aluminum". At the same time, under this name, both high-quality products made of AlMg3.5% alloy, which are used by European manufacturers, and products made of cheap AlMg1% alloy, manufactured in China and Taiwan and supplied to the market directly to the market, are sold under this name.