443


UNI 8111

TRILOBULAR SCREWS HEX WASHER HEAD
The self-forming trilobular screw is a triangular section screw with metric thread suitable for direct screwing in blind or through holes. Its main feature is to avoid the threading phase in steel and light alloy products. During screwing, this screw forms the thread plastically, i.e. by deforming the material, thus creating a play-free coupling between screw and nut, thus guaranteeing optimal fastening with high resistance to tearing and unscrewing due to the vibrations of use. The creation of the thread in this condition avoids the formation of shavings, a feature particularly required by several regulations concerning threads on blind holes. Regardless of the length of the screw, the efficiency of this thread is expressed in the first 20 / 25mm only starting from the tip. The presence of a longer thread length does not affect the screw's sealing capacity. The utmost attention must be paid to the holes or die-casting pins that will be used for the creation of the holes: an incorrect hole even if only five cents can in some cases radically change the tightness of the screw. It should also be said that not all the tables in circulation are correct for the use of the screws in question; this situation was created following the regulatory grouping of various types of self-forming screws, which however had different characteristics and therefore different holes of use. From our long and affirmed technical experience we can maintain that the hole suitable for any type of use is four or five tenths maximum smaller than the nominal diameter of the screw; in case of die-casting, a maximum taper of one degree must be calculated. Different tapers can create problems during particularly heavy tightening, as they interfere with the regulation of the screw: it can in fact have a forming part of four times its own pitch. Our trefoil screws, in addition to the galvanic treatment according to RoHs regulation, are subjected to a lubrication treatment, necessary to reduce the screwing effort by 30%.

Compared to the cross recess, the hexagonal head guarantees the possibility of applying a higher tightening torque without the risk of the insert coming out. It is particularly indicated in the most demanding assemblies, i.e. those in which a high tightening torque is applied.

The length of the screw is measured from the tip to the underhead.

Code Description Availability Certifications Request offer
443.0306ZN VITI TRILOBATE 3X 6 TEFR UNI 8111 ZINCATE Cr.3 220000.0
443.0308ZN VITI TRILOBATE 3X 8 TEFR UNI 8111 ZINCATE Cr.3 175000.0
443.0310ZN VITI TRILOBATE 3X10 TEFR UNI 8111 ZINCATE Cr.3 282000.0
443.0312ZN VITI TRILOBATE 3X12 TEFR UNI 8111 ZINCATE Cr.3 155000.0
443.0315ZN VITI TRILOBATE 3X15 TEFR UNI 8111 ZINCATE Cr.3 66300.0
443.0320ZN VITI TRILOBATE 3X20 TEFR UNI 8111 ZINCATE Cr.3 37250.0
443.0406ZN VITI TRILOBATE 4X 6 TEFR UNI 8111 ZINCATE Cr.3 214350.0
443.0408ZN VITI TRILOBATE 4X 8 TEFR UNI 8111 ZINCATE Cr.3 0.0
443.0410ZN VITI TRILOBATE 4X10 TEFR UNI 8111 ZINCATE Cr.3 155300.0
443.0410ZO VITI TRILOBATE 4X10 TEFR UNI 8111 Z.NERO Cr.3 0.0
443.0412ZN VITI TRILOBATE 4X12 TEFR UNI 8111 ZINCATE Cr.3 0.0
443.0412ZO VITI TRILOBATE 4X12 TEFR UNI 8111 Z.NERE Cr.3 0.0
443.0415ZN VITI TRILOBATE 4X15 TEFR UNI 8111 ZINCATE Cr.3 111206.0
443.0420ZN VITI TRILOBATE 4X20 TEFR UNI 8111 ZINCATE Cr.3 181000.0
443.0435ZN VITI TRILOBATE 4X35 TEFR UNI 8111 ZINCATE Cr.3 0.0
443.0508ZN VITI TRILOBATE 5X 8 TEFR UNI 8111 ZINCATE Cr.3 324000.0
443.0510ZN VITI TRILOBATE 5X10 TEFR UNI 8111 ZINCATE Cr.3 0.0
443.0510ZO VITI TRILOBATE 5X10 TEFR UNI 8111 Z.NERO Cr.3 0.0
443.0512ZN VITI TRILOBATE 5X12 TEFR UNI 8111 ZINCATE Cr.3 0.0
443.0512ZO VITI TRILOBATE 5X12 TEFR UNI 8111 Z.NERE Cr.3 0.0
443.0515ZN VITI TRILOBATE 5X15 TEFR UNI 8111 ZINCATE Cr.3 67100.0
443.0515ZO VITI TRILOBATE 5X15 TEFR UNI 8111 ZINCATE NERE Cr.3 + S 0.0
443.0516ZN VITI TRILOBATE 5X16 TEFR UNI 8111 ZINCATE Cr.3 0.0
443.0518ZN VITI TRILOBATE 5X18 TEFR UNI 8111 ZINCATE Cr.3 0.0
443.0520ZN VITI TRILOBATE 5X20 TEFR UNI 8111 ZINCATE Cr.3 319900.0
443.0522ZN VITI TRILOBATE 5X22 TEFR UNI 8111 ZINCATE Cr.3 52900.0
443.0525ZN VITI TRILOBATE 5X25 TEFR UNI 8111 ZINCATE Cr.3 60685.0
443.0530ZN VITI TRILOBATE 5X30 TEFR UNI 8111 ZINCATE Cr.3 98500.0
443.0535ZN VITI TRILOBATE 5X35 TEFR UNI 8111 ZINCATE Cr.3 34500.0
443.0540ZN VITI TRILOBATE 5X40 TEFR UNI 8111 ZINCATE Cr.3 0.0
443.0550ZN VITI TRILOBATE 5X50 TEFR UNI 8111 ZINCATE Cr.3 0.0
443.0608ZN VITI TRILOBATE 6X 8 TEFR UNI 8111 ZINCATE Cr.3 67400.0
443.0610ZN VITI TRILOBATE 6X10 TEFR UNI 8111 ZINCATE Cr.3 25000.0
443.0612ZN VITI TRILOBATE 6X12 TEFR UNI 8111 ZINCATE Cr.3 2600.0
443.0612ZO VITI TRILOBATE 6X12 TEFR UNI 8111 Z.NERE Cr.3 0.0
443.0614ZN VITI TRILOBATE 6X14 TEFR UNI 8111 ZINCATE Cr.3 0.0
443.0615GEO VITI TRILOBATE 6X15 TEFR UNI 8111 GEOMET 321A 0.0
443.0615ZN VITI TRILOBATE 6X15 TEFR UNI 8111 ZINCATE Cr.3 0.0
443.0615ZNK720 VITI TRILOBATE 6X15 TEFR UNI 8111 ZINCO NIKEL GRIGIO 720 h 0.0
443.0620ZN VITI TRILOBATE 6X20 TEFR UNI 8111 ZINCATE Cr.3 225925.0
443.0625ZN VITI TRILOBATE 6X25 TEFR UNI 8111 ZINCATE Cr.3 0.0
443.0630ZN VITI TRILOBATE 6X30 TEFR UNI 8111 ZINCATE Cr.3 1000.0
443.0635ZN VITI TRILOBATE 6X35 TEFR UNI 8111 ZINCATE Cr.3 116600.0
443.0640ZN VITI TRILOBATE 6X40 TEFR UNI 8111 ZINCATE Cr.3 32215.0
443.0645ZN VITI TRILOBATE 6X45 TEFR UNI 8111 ZINCATE Cr.3 14000.0
443.0812ZN VITI TRILOBATE 8X12 TEFR UNI 8111 ZINCATE Cr.3 13500.0
443.0815ZN VITI TRILOBATE 8X15 TEFR UNI 8111 ZINCATE Cr.3 0.0
443.0816GEO VITI TRILOBATE 8X16 TEFR UNI 8111 GEOMET 321A + ML PLUS 0.0
443.0820ZN VITI TRILOBATE 8X20 TEFR UNI 8111 ZINCATE Cr.3 33100.0
443.0825ZN VITI TRILOBATE 8X25 TEFR UNI 8111 ZINCATE Cr.3 0.0
443.0830ZN VITI TRILOBATE 8X30 TEFR UNI 8111 ZINCATE Cr.3 4000.0
443.0835ZN VITI TRILOBATE 8X35 TEFR UNI 8111 ZINCATE Cr.3 0.0
443.0840ZN VITI TRILOBATE 8X40 TEFR UNI 8111 ZINCATE Cr.3 0.0
443.1016ZN VITI TRILOBATE 10X16 TEFR UNI 8111 ZINCATE Cr.3 0.0
443.1020ZN VITI TRILOBATE 10X20 TEFR UNI 8111 ZINCATE Cr.3 32790.0
443.1025ZN VITI TRILOBATE 10X25 TEFR UNI 8111 ZINCATE Cr.3 0.0
443.1030ZN VITI TRILOBATE 10X30 TEFR UNI 8111 ZINCATE Cr.3 0.0
443.1035ZN VITI TRILOBATE 10X35 TEFR UNI 8111 ZINCATE Cr.3 6265.0
443.1040ZN VITI TRILOBATE 10X40 TEFR UNI 8111 ZINCATE Cr.3 12125.0
443.1045ZN VITI TRILOBATE 10X45 TEFR UNI 8111 ZINCATE Cr.3 5239.0
443.1050ZN VITI TRILOBATE 10X50 TEFR UNI 8111 ZINCATE Cr.3 5900.0