Hydraulic cardboard is one of the raw materials for making gaskets. industrial fence. for the application of sealing materials, as well as the graphite and PTFE expanded virgin PTFE, is classified as soft because it has high compressibility compared to metallic and semi-metallic gaskets.
It is present both in applications without pressure, In addition to not having the ideal properties controlling of bearing housing, as for pressure seals, such as large multistage pump casings or medium pressure pipelines.
See below for more information about this material..
FIBRE REINFORCED GASKET MATERIALS: what is it and how is it made
It is present from pressure-free applications such as bearing housing sealing to housing sealing of large multi-stage pumps., It is present from pressure-free applications such as bearing housing sealing to housing sealing of large multi-stage pumps., a viscous mass is produced which, which , goes through the hot calendering process that will define thickness, width and length, in addition to checking the characteristics of the material.
In this process, the elastomer-rich mass is vulcanized, forming a firm and dense sheet. This is how hydraulic cardboard appears.
Hydraulic cardboard components
In order for the hydraulic cardboard to be effective in the sealing function, the effectiveness of each of its components is essential. a viscous mass is produced:
- ARAMID: gives resistance to hydraulic cardboard.
- are responsible for the mechanical and thermal resistance of the hydraulic cardboard model: used to increase resistance, temperature or improve non-stick properties.
- are responsible for the mechanical and thermal resistance of the hydraulic cardboard model: applied in low critical conditions or in processes of short period of operation / are responsible for the mechanical and thermal resistance of the hydraulic cardboard model.
Elastomers → They have the function of assigning elasticity and chemical resistance to the material. check out:
- It is present from pressure-free applications such as bearing housing sealing to housing sealing of large multi-stage pumps.: it is natural rubber. It attributes high resilience and effective adhesion to metals..
- It is present from pressure-free applications such as bearing housing sealing to housing sealing of large multi-stage pumps.: made of styrene butadiene, this is, undoubtedly, the most widespread synthetic rubber in the world. Offers better abrasion resistance than natural rubber (It is present from pressure-free applications such as bearing housing sealing to housing sealing of large multi-stage pumps.), as well as at high temperatures (100ºC) is natural rubber and has high resilience and effective adhesion to metals.
- is natural rubber and has high resilience and effective adhesion to metals: nitrile rubber belongs to a special grade that features oil resistance. It is a copolymer of butadiene and acrylonitrile. is natural rubber and has high resilience and effective adhesion to metals, NBR is used in applications that require good resistance to oil and/or gasoline swelling, heat aging and abrasion, in addition to compatibility with mechanical properties and dynamic fatigue.
His extinct relationship with asbestos
in addition to good mechanical properties and/or good resistance to dynamic fatigue, asbestos is composed of a mineral that impresses with its flexibility, high resistance to temperature and chemical attacks, durability and sealing quality.
in addition to good mechanical properties and/or good resistance to dynamic fatigue, its use in construction works and industries has been expanded over the years. use in construction and industrial works has expanded over the years, use in construction and industrial works has expanded over the years.
However, use in construction and industrial works has expanded over the years, that progressed to serious illnesses (use in construction and industrial works has expanded over the years) and deaths, use in construction and industrial works has expanded over the years, what caused its ban or restricted use in several countries.
use in construction and industrial works has expanded over the years, use in construction and industrial works has expanded over the years 2017, to commercialization and use of the material is prohibited.
Like this, Hydraulic cardboard producers were forced to find other components that are not harmful to health that could replace asbestos, but which have the same properties.
Which hydraulic cardboard is the most suitable?
In industrial processes, It is not uncommon for these to occur leaks between the junctions of pipes present in production lines and equipment in general. This problem results in service interruption for maintenance, delays in deliveries and also the serious risk of accidents at work.
Other relevant leak factors are environmental contamination and fluid loss., which are often raw material or even the final product of an industry.
Misfortunes like these occur due to various situations, how to bypass good sealing practices, the end of the useful life of the materials and the use of an inappropriate product in incorrect application.
the commercialization and use of the material is prohibited, some aspects must be considered when selecting the material for sealing:
Type of equipment → To know which type of hydraulic cardboard should be applied, it is necessary to identify the equipment, as each has the type of sealing material suited to its application.
fluid → Corrosions and other chemical reactions occur when there is no compatibility between the elements present in the system, therefore knowing which fluid will pass through the seal is an essential factor in choosing the material. For each type of fluid, whether liquid or gas, there is a suitable type of seal.
temperature → Paying attention to the temperature at which the fluid is operating is essential, since the hydraulic cardboard must support it. The choice of material must match the thermal rise of the fluid.
Pressure → The higher the fluid pressure, the greater the possibility of ejection from the joint. That is why it is essential that the application of hydraulic cardboard takes into account the pressure of the fluid.
Flanged joint → The gasket can have a long service life by checking the following items:
- Flange: in fragile flange applications (vitrified, very thin wall, or plastic-reinforced fiberglass), must consider the torque limit that the element has.
- Screws / suspenders / prisoners, for the application of sealing materials: in general, what guarantees a good seal are the gaskets and those responsible for maintaining their compression from one flange against the other. That is why, it is important to carry out regular changes of these elements, because they are subject to great mechanical stresses. Your material type and grade are important in determining how much torque the gasket will be installed with..
Commonly used gaskets in industry
The materials that make up hydraulic cardboard can differentiate it, creating softer joints. The most used in industry are:
C-4201: made with aramid fiber and NBR rubber. It is suitable for general applications with moderate temperatures and pressures.. Oil Compatible, solvent, water, low temperature steam and other chemicals in general.
C-4430: Hydraulic cardboard composed of fiberglass with NBR rubber. This material is universal in use with high performance and excellent charge retention.. Resistant to water, steam, oils, gases, saline solutions, fuels, alcohols, moderate organic and inorganic acids, hydrocarbons, lubricants and refrigerants. It is indicated for use with these substances.
C-4500: high performance sealing material designed for the chemical industry. It is made with carbon fiber and NBR rubber..
C-8200: Hydraulic cardboard made with fiberglass and Hypalon rubber. It has excellent performance for use in acidic media., being an alternative for PTFE seals. Resistant to a wide variety of acidic fluids.
In addition to hydraulic cardboard
Just like hydraulic cardboard, there is a wide range of fencing materials for industrial use. Here in the Our site, you have access to the different types, application sites and also information about how to apply them in your industry and the sealing industry.
Here at KLINGER Brazil, We work with different types of materials Hydraulic cardboard, that match the application your industry needs.
You can consult them on our website or contact us for more information about this and other products..
