Unbrako fasteners known for quality, safety and innovation for over 100 years, are now also available in austenitic stainless steel – 304 and 316

 Unbrako fasteners are now into stainless steel. These are considered to be ideal for corrosive, magnetic, hygienic, cryogenic or elevated temperature environments. Unbrako stainless screws offer good resistance to rust and corrosion from acids, organic substances, salt solutions and atmospheres. Its notable properties include retention of a high percentage of tensile strength and good creep resistance up to 800 F, without scaling or oxidation.

A complete range of Unbrako stainless steel fasteners including socket head screws, hex head screws and nuts, washers (plain and spring), threaded rod and socket set screws are now available in A2-70, A4-70 and A4-80.

Why stainless steel? Why Unbrako?
Today, with labour costs at record levels and going up, greater consideration at the design level is being given to the reduction, or even elimination of maintenance. The cost of removing rusty bolts and replacing them with the new ones is more expensive than using corrosion resistant fasteners to begin with. Other costs resulting from fastener failure, such as downtime and lost production, make an even stronger case for stainless steel fasteners.

Unbrako stainless steel fasteners, available in SS304 and SS316, offer excellent corrosion resistance in a wide variety of environments, especially in low chloride waters (less than 2000 ppm chlorides). Additionally, they are nobler (cathodic) than the structural members they join, and are therefore protected by them.

Unbrako SS304 fasteners are used in many applications. They are virtually immune to foodstuffs, sterilising solutions, most organic chemicals and dyestuffs, and a wide variety of inorganic chemicals. They are thus useful in the food and beverage, pharmaceutical and electronic chip industries, as they maintain product purity, with the minimum contamination.
However, if an application calls for a material with corrosion resistant properties better than that of SS304, SS316 is the logical candidate. The 2-3 per cent molybdenum provides improved pitting and crevice corrosion resistant properties, especially in environments containing chlorides. Unbrako SS316 fasteners find their applications in pulp and paper mills and water treatment plants. They are also used in phosphoric and acetic acids.

Unbrako stainless steel fasteners do not require any form of protective coating. This stainless characteristic makes them suitable for many architectural applications and atmospheric (indoor and outdoor) services.

Performance at high temperatures
At elevated temperatures creep occurs leading to reduction in stress, which means bolts are unable to maintain a tight joint. Unbrako stainless steel fasteners show retention of a high percentage of tensile strength and good creep resistance up to 800 F (without scaling or oxidation).

Performance at low temperatures
Unbrako stainless steel fasteners show quality performance even at low temperatures. They are essentially useful in cryogenic applications like Liquid Nitrogen Gas (LNG) processing, especially SS304, because it does not become brittle as it is chilled. It not only remains tough and ductile at LNG temperature (-) 260F, but also retains excellent properties with liquid hydrogen at (-) 423F and liquid helium at (-) 452F.