Valmont Structures Material Specifications

Valmont Structures Material Specifications

Our Columns and brackets are produced from S235, S275 S355 and or S450 high strength steels. These grades of steel conform with the following standards or the equivalent steel following international standards:

EN10149: Hot rolled flat products of high yield strength steels for cold forming.
EN10210: Hot finished structural hollow sections of non-alloy and fine grain structural steels..
EN10219: Cold formed structural hollow section of non-alloy fine grain steels.
EN10025: Hot rolled products of non-alloy structural steels – Technical delivery conditions (includes amendment A1:1993).

Galvanising: In order to obtain the best quality galvanising for our products, all steel used is closely monitored for silicon content and it’s suitability for the galvanising processes. The galvanising process and testing fully complies with EN ISO 1461:2009.

Hot rolled flat products in High-Strength Steel obtained by cold shaping:This new Steel is obtained by the addition of micro alloy elements (Titanium, Niobium, Vanadium…), which increases its resistance and makes it easier to weld, whilst maintaining good cold deformation. It also has better corrosion resistance.

Hot rolled products are made of type S235 Construction Steel: Alloy composed mainly of Iron with Carbon to which different elements (Manganese, Silicon, etc.) are added in order to obtain minimal mechanical resistance.

 

Tubular Column Production Line
The manufacturing of Valmont tubular columns begins with the cutting of the chosen tube to the correct length for the base of the column. The tube is then thoroughly de-burred at the point of the cut ensuring no sharp edges are left on the tube.

We then need to shape the base at the cutting point to receive the shaft. This is done by applying pressure to the base with dies. These dies control the shape of the base, we can choose different dies to accommodate a wide range of shaft diameters.

After the shaping of the base we then need to put the door and the cable slot in the desired place. This is done by an automated plasma burner that can be programmed to whatever shape and size of our choosing.

Once the door and cable slot have been cut out the base can then be sent to final assembly where the shaft can be fitted. The shaft can be shaped in the same manner as the base to receive all sorts of different bracket fittings.

During assembly the back plates are welded into the base compartment ready to receive the base board. Any other internal fittings are welded into the base at this stage. 

Our columns and brackets are produced from Grade 304L & 316L austenitic stainless steel. These types of steel conform with following standards:

EN10088-2: Stainless Steel.
1.4301 - XBS1449: Grade 304L.
1.4401 - XBS1449: Grade 316L.

Corrosion Resistance:The corrosion resistance of stainless steel is attributed to the thin passive film that forms spontaneously on its surface in oxidizing environments if the steel has a minimum chromium content of approximately 10.5%.(Which both Gr304L and 316L do).

As the film adheres strongly to the metal substrate and protects it from contact with the surrounding environment, the electrochemical reactions that cause corrosion are effectively stopped. If locally destroyed, for example by scratching, the film can ‘heal’ by spontaneously re-passivating in an oxidizing environment.

Finishing: Due to largely being used as roadside structures, we opt for a process of stainless steel bead abrading to create a homogenous automated satin finish which can be sealed with a clear coating upon request. Although not advised for roadside due to glare issues, both mirror finishing and electroplating are available for decorative stainless structures.

Corten is a weather-resistant steel alloy that has been optimized with copper, chromium, nickel and phosphorus. When exposed to weather. Corten steel develops a rich patina which protects and has greatly boosted its popularity over the last few years.

Valmont offers this product range in two different finishing options as standard.

Valmont Corten products are designed to meet EN 40-5 standards and carry CE Certification.

Corten Finish Options: Valmont offers this product range in two different finishing options as standard.

The Natural Finish: This process is carried out to provide Corten steel a natural patina, that will result as a natural, living Corten surface.

The process starts with cleaning of the product surfaces to remove grease and any other impurities. After this the product is starting to corrode from ambient humidity. This procedure continues and accelerates once installed (environmental effects, rain and drying) and finally the product will achieve the final stage of natural patina. Depending on the location and conditions this typically takes several months.

As this method complements Corten steel’s natural characteristics, some staining (clothes etc.) may occur if the product is touched by individuals.

The Accelerated Finish: This process features accelerated patina build-up, which provides good homogeneity of the surface finish. The rusting process is activated with a chemical, which is applied at least twice. After 3-4 days the rusting process has typically achieved its characteristics. At this point the level of rust is inspected visually, and should the aesthetics demand, additional chemical treatment with the same substance can be performed.

When the corrosion level has reached the customer’s visual demand a stopping bath is applied to halt any further corrosion. This water-based acrylic sealant also reduces Corten steel’s staining features substantially.

Our poles are produced from 6060T5 Aluminium alloy, the brackets and other tubular elements from 6060T6 alloy, the backing plates from 5038H111, the resistance elements from AlSi7Mg or AlSi10Mg cast Aluminium and decorative parts in AlSi13 cast Aluminium.

These Aluminium alloys comply with NF EN 755 series standards for conical posts, brackets and other tubular parts as well as backing plates, and standard NF EN 1706 for parts in cast Aluminium.

Bars, tubes and spun profiles - 6060T5 or T6:
The mechanical characteristics are obtained by tempering and rendering. Valmont’s specific rendering treatment makes it possible to obtain above-standard mechanical characteristics. The 6060 alloy is a good compromise between mechanical strength and corrosion; it is particularly apt for anodising and cold deforming. Good welding results are obtained with classic procedures under inert gas (TIG or MIG).

Piece of cast Aluminium AlSi7Mg and AlSi10Mg:
There are two main casting processes used - sand or shell - according to the geometrical complexity of the product, the degree of precision needed for the dimensions and the quantities to be produced. According to the level of resistance required, the pieces can be heat treated.

The Aluminium Process
Valmont aluminium columns are formed via cold tapering.

After the aluminium tubes have been received and stocked in the production workshop, the tubes are then cut to length according to the technical specifications of the products to be manufactured, and automatically put into a storeroom for rough products. When they leave the storeroom, the tubes are automatically taken to the tapering machine.

The tapering operation consists of cold embossing the raw tubes to give them the required shape. This process is called cold spinning treatment. This spinning machine is made of a broach and a tailstock, which turns the raw shaft, then a shaping carriage made up of specific rollers moves along it and models the product following the technical specifications programmed into the machine.

Depending on the size of the end products, 1, 2, 3 or 4 can be made from one raw shaft. Once tapered, the raw shaft is moved to a saw bench where it will be cut to length. This whole tapering process is entirely automatic: the 3D product models made by our design department are directly sent to the machine’s digital controls; the operator checks the data and then launches the production process.

This expertise and the machine’s technical abilities allow us to produce complex shapes and obtain large tapering ratios.

The Aluminium Production Line
A rendering furnace, where the rough tapered tubes are heated for 6 hours to acquire the mechanical strength fixed by our technical specifications. The products are checked as they leave the furnace to ensure that our products are well above minimum values.

After cooling, the tapered tubes are straightened and sent to the polishing line. 2 polishing operations are performed on 2 specific machines: the first gives a rough polish and the second carries out the finishing, which gives the end product that brushed and polished appearance.

The next stage is cutting the door. The tapered tube is held in clamps and a horizontal saw with a thin band saw blade does the cutting. Thus the door is perfectly adjusted in relation to the shape cut in the column. On the same machine, we reinforce the opening if necessary. This operation consists of expanding a strengthening tube inside the pole.

The last stage on this line is welding the base plates; this is done by qualified welders.

The column thus produced are moved to a storage zone within the factory. Access doors are equipped and assembled. Any specific operations seen to be necessary are performed, followed by the final control before individual packing and sending them to the client, putting them in stock or sending them for painting on our powder coating line.

Our poles are made from planks of Class 3 glue-laminated untreated Scots Pine beams.

Our beams are designed and certified GL28h. There are 4 classes of resistance, GL24, 28, 32 and 36h, by increasing order of resistance.

Glue Laminated Beams
The maximum thickness of the planks making up the beam is less than 34m, in conformity with Eurocode 5 registered as “Mixed Wood Metal Lamp posts”. The glue used to assemble the planks is known as White glue, and has the advantage of minimising the visual impact of joints on the wooden parts. Like the Scotch pine from Finland used for our production, our end products are PEFC* certified, certificate 5674-01.

Steel Components
The metal parts of these “Mixed Wood Metal Lighting Columns” are made of S235 Galvanised Steel. To obtain the best quality Galvanising, the Steel used is category A in conformity with standard NF A 35-503.



Hot rolled products made of type S235 Construction Steel:
Alloy composed mainly of Iron with Carbon to which different elements (Manganese, Silicon, etc.) are added in order to obtain minimal mechanical resistance.

Wooden Column Production
Our production line for wooden columns transforms GL28h laminated pine beams into mixed Steel/Wooden columns, entirely finished with base plate and equipment inside the door. Once production is complete, the columns are sent directly to clients.

The Production Line:The manufacturing of the masts begins by cutting off the extremities of the beam according to the height of the final product. Next, a central hole is drilled along the length of the column to allow cabling to pass.

Cylindrical section columns are produced using the same machining centre. Initially all cylindrical section columns have a multi-faceted profile. Depending on the final design, the column may then be sanded in order to smooth these facets and obtain the final shape.

Square-section columns are produced by a digital machining centre. Also at this point, additional cuts are made in wood to allow the steel base and top cap to be fitted.

Standard columns of heights taller than 5m are produced in several parts. The parts of the column go through a digital machining centre where finger joints are placed on the end surfaces to be joined. The joining and gluing operations needed to ensure a strong and permanent connection are performed next.

The assembly technology used to produce these columns complies with current calculation rules.

Finishing
All holes needed to fix accessories and/or lights are then made in the wooden column as per the required specification.

All columns are then treated to a 4 layer protective coating system which is designed to maximise the life span of the wooden column.

The steel base, is then securely fitted and glued to the pole. The adapters or other parts designed to fasten lanterns and/ or accessories are also put into position at this time. Once all fasteners are installed the products are then packaged for delivery.

Packaging: Several thicknesses of corrugated cardboard protect the wooden section, while a felt sleeve protects the steel base.

The columns are then placed top to bottom on a pallet, separated from each other by wooden wedges which follow the section of the mast to avoid slipping during transport.

The operator takes care to balance the pallet according to the weight and length of the masts. Placing its centre of gravity directly above the position of the pallet truck forks. The bundle is further protected by a wooden plaque in order to prevent any damage from forks. Lastly, a plastic film is added to ensure that rain cannot deteriorate the cardboard envelope packaging during transport.