Page 255 - Catalogo MRF FR

RAW MATERIALS AND FINISHING OF MRF PRODUCTS drawing. When our products are welded by the bodybuilder, the following
recommendations should be taken into account:
MRF manufactures components in these types of materials:
Weiding of our stainless steel parts:
1. Stainless steels
For correct welding, we recommend welding our parts with AlSI 308L wire.
AISI304 austenitic stainless steels are very versatile, corrosion resistant and To optimise the appearance and durability of the welded surface, it is advisable
with good mechanical properties, which depend on the admissible degrees of to use one of the following two methods: the usual residues, excess filler
Cr and Ni present in the material. The ability of this steel to passivate enables material or projections on welded surfaces should be removed mechanically
it to spontaneously self-repair if damaged, by re-coating itself with this passive with a stainless steel brush and/or by acid pickling followed by washing.
layer. This distinguishes it from inert protective coatings, such as paints or

coatings, wher loc remain. mechanic str Welding of zinc-plat parts:
yield strength are superior to carbon steels. It is possible to weld already zinc-plated components. Obviously, the weld seams
do not have a corrosion resistance equivalent to the galvanised component
In some specific components, AISI303 stainless steel is used for machined itself. However, we recommend welding with ER70-S6 wire for a longer service
parts and fasteners or AISI302 for springs. life. After performing this welding, it is advisable to apply a special paint which
All components are subjected to a cleaning and pickling process after the allows the weld to be locally protected and to achieve consistency of appearance

dra processes. way, guar with the rest of the components.
of oxides and deposited particles, maintaining their corrosion resistance and Assembly:
surface appearance.
The tubes of the locks always have a manufacturing tolerance. Correct
Our stainless steel products have a mirror polished finish by default. On positioning of the tube guides compensates for the manufacturing tolerance of
request, they can be supplied with a matt finish. the tube and ensures the correct functioning of the lock.
In addition to the finish, we offer the possibility of engraving the customer’s In addition, the installation of anti-rack washers is recommended to prevent
logo on most of our stainless steel products. possible movement of the lock or door that could cause damage to components,
especially in enclosures with low structural rigidity. The locj in its final position
2. Zinc plated carbon steel
must be perfectly aligned, otherwise stresses may be generated which could
Low carbon steel with a low carbon content facilitates cold drawing and has a cause a component to break.
high weldability. Handle springs are absolutely necessary to guarantee the correct functioning of
We subject our products to a Chromium Vi-free electrolytic zinc plating the lock and must therefore be installed.
process. This process increases the protection against corrosion and gives an Note
aesthetically pleasing surface appearance.
The data on the weight of each reference, indicated in this catalogue, may not
The life of the zinc coating on steel depends on the mass of zinc per unit area correspond ta the real weight due to a tolerance of +6% due to the European
and the aggressiveness of the environment to which it is exposed. Exposure to Standard for the supply of raw materials.
aggressive environmental conditions, use and maintenance will shorten the life
of the zinc coating. CLEANING AND MAINTENANCE RECOMMENDATIONS
MRF can also supply parts with other surface finishes: lacquering, nickel The cleaning and maintenance of the seals will depend to a large extent on the
plating, chrome plating, zinc-nickel plating, black zinc plating and others at the weather conditions under which they are to be used. A product working under
customer’s request. aggressive conditions type C4 or C5, according to ISO 12944, will require much
3. Other materials: more maintenance than a product working in environments type C1 or C2,
In special applications requiring corrosion resistance higher than AISI304, according to the aforementioned standard.
AISI316 stainless steel is used. This material is usually used in marine Standard maintenance consists of cleaning with fresh water and a clean cloth.
applic aggr Here are some specific indicatians on how to clean the parts depending on the
environments. type of stain:
requir mechanic Type How to clean?
anti-corrosion properties of steels.
Finguer 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 manufacturing Marks in shiny polished parts With glass cleaner
processes, verifying this point by means of Studies and tests. More stubbron marks and water Mild creamy household cleaners.
Then use deionised water
RECOMMENDATIONS FOR ASSEMBLY AND USE OF MRF PRODUCTS Grease and oil stains With products containing alcohol or
Contact between different materials: the “stack effect’: acetone
Cleaning agents containing chlorides, especially those containing
Whenever there is contact between our AISI 304 parts and other metallic hydrochloric acid, must not be used.
components of poorer performance such as carbon steel or aluminium, the so-
called “stack effect” can occur. The less noble metal is oxidised by the presence Alkalis and shampoos should not be mixed, as they may react with each
of a more nable metal. We recommend the use of components, fasteners other and cause corrosion.
pr contact, It is very important to rinse thoroughly after cleaning, because in areas

installation by the customer. wher ther fr spaces, w c

Prevention of product degradation during the assembly process: accumulate and become stagnant and aggressive to the materials.
Use of grease:
It is desirable to prevent the projection of shavings or particles on our parts,
coming from drilling or cutting carbon steel. These could cause a deterioration The wear of the fastening surfaces on espagnoletie 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 offers its customers the possibility of supplying the complete welded lock,
including handle, tube and cams, subject to confirmation of the customer’s

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