All screws are manufactured on CNC machines (except screws in the color transparent anodized).
JM screws are therefore from outstanding quality and perfect finish.
The threads are implemented in the roll procedure.
Note please that it does not concern with nearly all other offerers CNC manufactured screws.
These screws are manufactured in mass production in the cold forging procedure (pressed).
The in such a way manufactured screws have usually a scarred and surface different of the head radius,
as it with our very favorable screws vorkommem oabic farbenen can.
Kind of the metal:
Aluminum alloy AlZn5,5MgCu, EN AW-7075 (old person designation AlZnMgCu 1.5)
characteristics AL6/abbreviation AlZn5,5MgCu (7075)/work off number 3,4365 according
to DIN 1,725 part of 1/ISO R 209
Durchschnittliche mechanische Eigenschaften der Schrauben *)
| Dichte || 2,80 g/cm » || Zugfestigkeit || 540-600 N/qmm |
| Wärmeleitfähigkeit bei 20°C th qcm/ms°C || 0,29 || Streckgrenze || 420-480 N/qmm |
| Spezifischer Widerstand bei 20 °C W qmm/m || 0,055 || Bruchdehnung || 11-15 % |
| Linearer Ausdehnungskoeffizient zwischen 20°C und 100°C || 23,5 x 10-6 || Brinellhärte || 154-169 |
| Schmelzbereich || 475/635°C || || |
| *) || Die mechanischen Eigenschaften können sich mit dem Durchmesser ändern. |
Zusammenstellung der Legierung AlZnMgCu 1,5
| || Zn || Mg || Cu || Fe || Si || Mn || Cr || Ti || Al |
| Mindest-% || 5,1 || 2,1 || 1,2 || || || || 0,18 || || der Rest |
| Höchst-% || 6,1 || 2,9 || 2,0 || 0,5 || 0,4 || 0,2 || 0,35 || 0,2 || |
| || || || mit || Zn || >2 || || || || |
| || || || || Mg || || || || |
The surface treatments, which receive these pins, form an effective protection against weather
and industrial influences as well as the corrosion-promoting sea-climate.
The anodized screws, which exhibit a perfect corrosion resistance under normal operating
conditions, are not attacked by most chemical products. A use during contact with strong Basen
(sodium and potassium) and concentrated acids (salt and sulfuric acid) is to be advised against however.
It is particularly high, owing to the very low coefficient of friction (approx. 0.05), it permitted with low
torque data very effective tightening, without that the danger exists, the pins to destroy.
The relationship attraction strength/torque data lies between 500 and 600 kg.
The use of a torque wrench is recommendable.
All data are non-binding guide values and refer to dry screwed screws, when using screw paste, the torque must be reduced accordingly. The torque is not to be used with the TRL / TCS screws, since the hexagon socket is smaller and can be destroyed, so tighten them with care.
Below the maximally permissible torques:
Wearing parts and lock nuts:
Each screw should be nut-laterally with a semihard, flat wearing part from AlMg3, provided.
The lock nut must correspond to the same requirements regarding its composition and its
protection as the nut/mother.
In order to receive the insolubility, is to be refrained from the use of a device from steel.
We recommend the use of self-locking one-piece nuts/mothers.
Lengthens a screw:
The length of a screw is always measured without the head, e.g. a screw M6x30 has a pin length of 30mm.
Colored anodizes, or anodizes and kaliumbichromatisiert and greased.
In the following colors available: oabic = yellow green irisierend red,
blue, violet, gold, silver, black and green shining anodized
Screws and nuts/mothers before the assembly grease slightly (e.g. JM special screw paste) around seizing to avoid.