Page 253 - catalogomrf

RAW MATERIALS AND FINISHING OF MRF PRODUCTS
MRF manufactures components in these types of materials: To optimise the appearance and durability of the welded surface, it is advisable
1. Stainless steels to use one of the following two methods: the usual residues, excess filler
material or projections on welded surfaces should be removed mechanically
AISI304 austenitic stainless steels are very versatile, corrosion resistant and with a stainless steel brush and/or by acid pickling followed by washing.
with good mechanical properties, which depend on the admissible degrees of
Cr and Ni present in the material. The ability of this steel to passivate enables Welding of zinc-plated parts:
it to spontaneously self-repair if damaged, by re-coating itself with this passive It is possible to weld already zinc-plated components. Obviously, the weld
layer. This distinguishes it from inert protective coatings, such as paints or seams do not have a corrosion resistance equivalent to the galvanised
metallic coatings, where local damage will remain. Its mechanical strength component itself. However, we recommend welding with ER70-S6 wire for a
and yield strength are superior to carbon steels. longer service life. After performing this welding, it is advisable to apply a
In some specific components, AISI303 stainless steel is used for machined special paint which allows the weld to be locally protected and to achieve
parts and fasteners or AISI302 for springs. consistency of appearance with the rest of the components.
All components are subjected to a cleaning and pickling process after the Assembly:
drawing and welding processes. In this way, we guarantee the total elimination The tubes of the locks always have a manufacturing tolerance. Correct
of oxides and deposited particles, maintaining their corrosion resistance and positioning of the tube guides compensates for the manufacturing tolerance of
surface appearance. the tube and ensures the correct functioning of the lock.
Our stainless steel products have a mirror polished finish by default. On In addition, the installation of anti-rack washers is recommended to prevent
request, they can be supplied with a matt finish. possible movement of the lock or door that could cause damage to
In addition to the finish, we o er the possibility of engraving the customer's components, especially in enclosures with low structural rigidity. The locj in its
logo on most of our stainless steel products. final position must be perfectly aligned, otherwise stresses may be generated
which could cause a component to break.
2. Zinc plated carbon steel
Handle springs are absolutely necessary to guarantee the correct functioning
Low carbon steel with a low carbon content facilitates cold drawing and has a of the lock and must therefore be installed.
high weldability.
Note
We subject our products to a Chromium VI-free electrolytic zinc plating
process. This process increases the protection against corrosion and gives an The data on the weight of each reference, indicated in this catalogue, may not
aesthetically pleasing surface appearance. correspond to the real weight due to a tolerance of ±6% due to the European
Standard for the supply of raw materials.
The life of the zinc coating on steel depends on the mass of zinc per unit area
and the aggressiveness of the environment to which it is exposed. Exposure to
aggressive environmental conditions, use and maintenance will shorten the CLEANING AND MAINTENANCE RECOMMENDATIONS
life of the zinc coating.
The cleaning and maintenance of the seals will depend to a large extent on the
MRF can also supply parts with other surface finishes: lacquering, nickel weather conditions under which they are to be used. A product working under
plating, chrome plating, zinc-nickel plating, black zinc plating and others at the aggressive conditions type C4 or C5, according to ISO 12944, will require much
customer's request.
more maintenance than a product working in environments type C1 or C2,
3. Other materials: according to the aforementioned standard.
In special applications requiring corrosion resistance higher than AISI304, Standard maintenance consists of cleaning with fresh water and a clean cloth.
AISI316 stainless steel is used. This material is usually used in marine Here are some specific indications on how to clean the parts depending on the
applications or those that may be subjected to aggressive weather type of stain:
environments.
Aluminium is used for specific parts that do not require the mechanical and Type How to clean?
anti-corrosion properties of steels.
Finger marks With soap and water
MRF also has the capacity to manufacture with other materials at the
customer's request, provided that these materials are suitable for the Marks on shiny polished parts With glass cleaner
manufacturing processes, verifying this point by means of studies and tests. More stubborn marks and water Mild creamy household cleaners.
marks Then use deionised water
RECOMMENDATIONS FOR ASSEMBLY AND USE OF MRF Grease and oil stains With products containing alcohol or
PRODUCTS acetone
Contact between di erent materials: the "stack e ect":
Whenever there is contact between our AISI 304 parts and other metallic • Cleaning agents containing chlorides, especially those containing
components of poorer performance such as carbon steel or aluminium, the hydrochloric acid, must not be used.
so-called "stack e ect" can occur. The less noble metal is oxidised by the • Alkalis and shampoos should not be mixed, as they may react with each
presence of a more noble metal. We recommend the use of components, other and cause corrosion.
fasteners and rivets of the same material as the product with which it is in • It is very important to rinse thoroughly after cleaning, because in areas
contact, for installation by the customer. where there may be holes or free spaces, water or cleaning agents can
Prevention of product degradation during the assembly process: accumulate and become stagnant and aggressive to the materials.
It is desirable to prevent the projection of shavings or particles on our parts, Use of grease:
coming from drilling or cutting carbon steel. These could cause a deterioration The wear of the fastening surfaces on espagnolette bolts can be limited by the
of the stainless steel surface appearance by oxidising over time. They can also use of suitable industrial greases.
damage the passive layer that serves as a self-protection for the stainless
steel, which could lead to pitting corrosion.
We recommend removing these chips "mechanically" immediately or with a
stainless steel cleaner containing phosphoric acid.
Sealing of the fixing holes of the parts:
All holes drilled in panels, frames and doors must be sealed watertight before
fixing our parts to avoid the appearance of rust, coming from the interior
reinforcements.
Welding:
MRF o ers its customers the possibility of supplying the complete welded lock,
including handle, tube and cams, subject to confirmation of the customer's
drawing. When our products are welded by the bodybuilder, the following
recommendations should be taken into account:
Welding of our stainless steel parts:
For correct welding, we recommend welding our parts with AISI 308L wire.

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