Viticulture

Les piquets en acier profilé sont fabriqués essentiellement à partir de deux familles d’steelThose beginning with the letters DX (DX51, DX52...) and those beginning with the letter S (S235, S250 …).

STEEL DX 51:

- DX = mild steel for cold forming.
- Elasticity from 15KgF/mm².

STEEL S 250 :

- S = standardised steels for construction (buildings, bridges, ships, etc.)
- Elasticity from 25KgF/mm2 (+40%)

The elastic resistance is the most important mechanical characteristic for the manufacture of posts.

For the same profile and weight, an S250 steel post will have at least 40% more theoretical yield strength than a DX51 steel post.

Our posts are made exclusively from S 250 and S 320 steel.

- Continuous hot-dip galvanising Z 275This product is suitable for soils with a PH of between 6.5 and 8.5 (estimated lifetime, 25 years + or - 5 years).

- Continuous hot-dip galvanising ZAM 300 or warm piece by piece, will be suitable for PH below 6.5 or above 8.5, or for long life in basic soils (over 30 years).

- Galvanisation is always done hot in a zinc bath à 450° about.

The posts are subjected to two main forces:
- The first, in the direction of the row, is due to the machines. Stakes narrow will facilitate the passage of machines and tools. In addition, they will reduce the "shadow zone" on either side of the posts, which will optimise the quality of the work.
- The second, lateral, due to the winds. From sides deep and dishes will better resist the winds.

The shape of the Multipic L30+ has the above characteristics.

It is wrong to assume that wide poles are stronger than light ones. In the direction of the rows, wide "U" shaped posts have different bending strengths depending on the direction of the forces.

They have an essential role. They will condition the ease and speed of readings and depalletising which are 2 operations that are repeated every year.

LINGUETS :
Opt for stakes with a specific shape that prevents them from being driven into the stakes by harvesting machines (anti-entrapment).
The advantage of this is that it allows for mechanical trellising and untensioning of the lifting wires.

The L30+ posts have a reinforced base and a flexible top to ensure that the wires are held in place by a clip. They are also suitable for hilly terrain.

THE NOTCHES :
Prefer of notches said in " M "This is because the "H" shape is less effective in holding the threads.
U-shaped notches systematically require the use of staples to hold the lifting threads in place.
Z-notches should be avoided for lifting wires.
The "M, H and Z" notches are not very suitable for the mechanisation of lifting wires.

1° INSTALLATION OF THE INTERMEDIATE STAKES

PLANTING DEPTH :
Beyond the section of the post, it is the depth of planting in the ground that will give the best stability to the trellis. For profiled steel poles, the minimum depth should be 60 cm for poles less than 2 m. For posts of 2 m and over, apply the rule of 1/3 in the ground and 2/3 above ground. The rule is given for a spacing of 5 metres between posts.

Depths may vary depending on the nature of the soil:

- In very clayey soils, it is a good idea to increase them by at least 10 cm. Dry clay is very hard but when wet it is like "modelling clay". It deforms easily.
- In very stony soils, a 10 cm reduction can be made.
- Contrary to popular belief, sandy soils are the best texture for holding stakes. Indeed, sand is not compressible. Standard depths will do.
If these depths cannot be met, make a pre-hole, or reduce the distance between stakes.

PLANTING METHODS
It is important to have pressures or shocks in the axis of the posts.
- MANUAL PLANTING: Prefer a ramming ram.
- MECHANICAL PLANTING: prefer a hydraulic planter with percussion or friction rather than a mass system.
In difficult soils, (very dry soils, rock strata,...) use a water planter or a perforator (before the hole) to make it easier to drive in the stakes.
Planting with a sledgehammer (manual or mechanical), use a sledgehammer, available as an accessory to avoid damaging the heads.

2° INSTALLATION OF HEAD POSTS

DIRECTION OF PLANTING OF HEAD POSTS PROFILES

• Position the open side towards the mooring line.

INCLINATION OF THE HEAD POSTS

• The most suitable angle is around 20° or 40%.

HOW TO MEASURE AN ANGLE

• Measure vertically 1m from the ground.
• From this point measure 40 cm horizontally.
• The angle obtained is close to 20°.

DISTANCE BETWEEN THE FOOT OF THE POLE AND THE MOORING LINE

• The further away the line is from the foot of the head post, the more resistant it will be to being pulled out.
• This distance D shall be at least 80% of H.
• D = Distance between the mooring line and the foot of the head stake.
• H = Height above ground of the posts.
• D = 80% at MINIMUM of H

ATTACHMENT POINTS OF THE MOORING WIRES ON THE HEAD POST

- The top wire at least 20 cm from the head of the post.
- The bottom wire halfway between the top wire and the ground.

ATTENTION to traditions and preconceived ideas...

ROW LENGTH :
La longueur des rangs a très peu d’incidence sur les efforts que reçoivent les amarres. En effet, la résultante des forces à chaque piquet est égale à 0. Il n’y a pas de cumul des charges sur la longueur du rang.
The stresses on the ropes are mainly a function of the height above ground of the trellis and the distance between the stakes.
These same criteria should be taken into account when determining the strength of the posts.

GROUND HOLDING OF STAKES :

Hollow stakes (stakes with soil inside the stake, tube or profiled stakes without tips) will require more planting depth. This is because solid or hollow stakes appointed pushes the soil to the sides when sinking and thus creates an area of compacted soil around it, which increases holding power.

GAPS BETWEEN STAKES :
L’écart le mieux adapté est de 5m. Plus l’écart entre les piquets est important plus le palissage vieillira rapidement. En effet, les piquets et les fils, sont soumis à plus d’efforts.
Beyond 5m it is strongly advised to plant the stakes 10 cm higher and to increase the strength of the stakes (thickness) and the wires.

SANDY SOILS :
Dans les terrains sableux, les piquets tiennent mieux que dans les terrains argileux. En effet, le sable n’est pas compressible et s’oppose ainsi mieux aux efforts. L’argile mouillée se comporte comme de la « pâte à modeler ».

LEANING POSTS :
Un piquet penché montre qu’il n’a pas était assez planté, plié, cela montre qu’il manque de résistance (sauf si c’est une machine qui l’a plié).

OXIDATION OF THE EDGES :
Sur les piquets galvanisés à chaud en continu la rouille qui apparaitrait sur les tranchants ne migrera pas sous le ZINC. En effet il y a « fusion » entre l’acier et le zinc en première couche empêchant ainsi le passage de la rouille. Cette oxydation n’altèrera pas la résistance des piquets dans le temps.

RESISTANCE OF THE POLES :
Pour augmenter la résistance d’un piquet en bois ou en béton, il faudra augmenter la section. Pour un piquet en acier profilé, il suffira d’augmenter l’épaisseur du métal.

GALVANISATION :
Continuous or piece-by-piece hot-dip galvanising is always carried out in a zinc bath at approximately 450°.

HOT GALVANIZING WITH A CONTINUOUS SHOT (Sendzimir process) :

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Sur les piquets galvanisés à chaud en continu la rouille qui apparaitrait sur les tranchants ne migrera pas sous le ZINC. En effet il y a « fusion » entre l’acier et le zinc en première couche empêchant ainsi le passage de la rouille. Cette oxydation n’altèrera pas la résistance des piquets dans le temps.

HOT-DIP GALVANIZING PIECE BY PIECE :

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STEEL :

Plus de 60% des aciers utilisés dans le monde proviennent du recyclage. L’acier, comme le verre, ne perdent pas leurs propriétés au recyclage contrairement aux plastiques. Ne pas confondre acier RECYCLÉ et acier DECLASSÉ.

There are 2 steelmaking processes:

- The iron ore smelting industry 
- The scrap metal sector from the recovery of steel (recycling)

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