Sistemi di giunzione per nastri trasportatori

Transcription

1 64 Sistemi di giunzione per nastri trasportatori

2 HINGES FOR CONVEYOR BELTS The function of hinges is to mechanically join the belt in conveyor belts and in machine belts intended for handling in every industrial sector. They are designed to join belts with PVC, PU and rubber top cover, sliding on a plane, on flat rollers and on trough rollers. Our joints include three different belt installation systems: Teeth fixing through stainless steel hinges Copper tips fixing through stainless steel or galvanized hinges Hooked fixing through nylon hinges LA-series stainless steel hinges They are recommended for thin belts (thickness from 1.2 to 3 mm) for conveyors with small drums and when a minimum reinforcement of the belt is requested. The position of the teeth is especially designed to avoid belt cutting, even with 1-ply and thin belts. LA-type hinges are suitable to get into contact with foods of every type and can be easily joined, even using common pressing equipment. LB and LCL-series stainless steel or galvanized hinges For belt thickness above 4 mm. it is necessary to use strong-holding hinges. Hinges with round copper tips give additional advantages: The round cross-section of the tips does not cut the weft threads of the plies but groups them thus forming a cross core which withstands tensile stresses. Strength is especially high in belts with flexible weft. The installation of LB LCL and Flex hinges is made easier and faster by the use of specific staple gun plates. LNY-series nylon hinges LNY30 hinges made of PA 6.6 nylon are suitable for contact with food products of any type and can operate in the presence of metal detectors and similar devices. The hooked lock of components allows for their installation with just a socket punch and a hammer. Hinges are supplied with an adhesive template to facilitate their positioning. 65

3 CONSIDERATION ON THE CHOICE OF JOINT In order to choose the metal joint three main elements should be considered: Thickness of the belt to be joined Diameter of the rollers or drums to wrap the belt around Maximum belt tensile stress Chemical aspects caused by contact with the carried product and with the environment should also be considered and it is also necessary to check compliance and suitability. It is also important to consider possible mechanical actions that can affect the belt and the hinge (loading system, presence of deflectors, product accumulation and positioning function etc.). The first 2 elements are generally known and can be easily considered by consulting the selection diagrams reported in the following page. Tensile stress during conveyor full-load operation can be determined by calculation, but it is almost never known by the operators who attach the metal hinge and usually it is the operator s experience that determines the choice. The tests performed on joined belts with hinges and copper tips have proven that, under stress to break, the breakage happens almost always by breakage and ripping of the belt. It is clear that, in order to be valid, the indications on the strength of a joint need to refer to the belt and hinge assembly. We have therefore decided to determine the breaking strength for belts with standard characteristics and thickness from 2 to 5 mm joined with i-belt hinges and to put the data in the data sheets. Such information is poorly indicative unless the belt work load is assumable. Since the only catalogue data that gives indications on the strength of the textile insert of the belt is the 1% elongation strength, we have tried to determine a Safety Ratio resulting from the following formula: The safety ratio can only have indicative value since the breaking strength of the joint mainly depends on the characteristics of the belt weft yarn, while the 1% elongation strength depends on the characteristics of the warp yarn. For 2- or 3-ply belts it is advisable that CS is higher than 3. C.R. = Breaking strenght- T.R. = Hard Weft - Cop. = Top cover - T.A. 1% = Elongation strenght 1% C. R. Cs = Safety ratio T. A. 1% Note: the breaking strength was determined as an average on similar belts from different manufacturers 66

4 LA-SERIES METAL JOINTS BELT THICKNESS FROM 1.2 TO 2.8 MM. The LA-series hinges are recommended for thin belts and for conveyors with small drums. In all LA hinges the position of teeth is deliberately offset to avoid cutting the belt, even with very thin belts. The LA-series hinges can be easily installed by using common pressing equipment. Special characteristics: The LA-series non-magnetic stainless steel hinges are suitable to get into contact with foods of any type and compliant with FDA/EC regulations Minimum reinforcement** of the belt LA1 LA2 0,6 0,7 0,8 LA3 Technical data LA1 LA2 LA3 Conveyor s thickness 1,2-1,6 1,4-2,0 2,0-2,8 Comb s wheelbase Roll s minimum diameter Inox steel s thickness 0,6 0,7 0,8 Inox stick s diameter 1,3 1,3 1,6 Tension s joint resistance (dan/cm) Features of tested conveyor C.R. Conveyor 1 cloth T.R. - Thickness mm 1,5 - Cop T.A. 1%: 5 dan/cm 19,6 Conveyora 2 clothes T.R. - Thickness mm 1,35 - T.A. 1% 8 dan/cm 21,8 C.R. Conveyor a 2 clothes T.R. - Thickness mm 2,0 - T.A. 1% 8 dan/cm 30,4 C.R. Conveyor a 2 clothes T.R. - Thickness mm 2,5 - T.A. 12 dan/cm 50,4 67

5 LB-SERIES METAL JOINTS BELT THICKNESS FROM 2.0 TO 4.8 MM. The LB-series hinges are made of galvanized and non-magnetic stainless steel. They are suitable to join conveyor belts sliding on a plane or flat rollers for any type of indoor handling. Thanks to the round cross-section of the tips** and the excellent malleability of copper, they ensure high tensile stress strength. The LB hinges are easy to install both at the workshop and on site with the help of a hammer and cut-off scissors. They are supplied in boxes complete with tip sets and joining sticks. Tip sets are made of friable plastic material and are separated when installing the tip allowing for quick assembly. Special characteristics: High tensile stress strength Fast and easy assembly both at the workshop and on site. Equipment Supplied with plates** and staples positioned for an easy and quick installation LB 2/3 LB 4/ Item Conveyor s thickness Roll s minimum diameter Material Tips ø x H. Stick material LB 2/3 IL 2,0-3,0 60 Inox 2,2 x 10,5 Inox LB 4/5 IL 3,2-4,8 80 Inox 2,7 x 12,5 Inox LB 2/3 ZN 2,0-3,0 60 Zincato 2,2 x 10,5 Zincato LB 4/5 ZN 3,2-4,8 80 Zincato 2,7 x 12,5 Zincato 68

6 LCL-SERIES METAL JOINTS BELT THICKNESS FROM 4.2 TO 9.5 MM. The LCL-series hinges are made of galvanized and non-magnetic stainless steel. They are suitable to join conveyor belts sliding on a plane or flat rollers for any type of indoor handling. Thanks to the round cross-section of the tips** and the excellent malleability of copper, they ensure a high tensile stress strength. The LCL hinges are easy to install both at the workshop and on site with the help of a hammer and cut-off scissors. They are available in boxes containing hinges complete with copper tips and joining sticks. LCL 8 24 Special characteristics High tensile stress strength Easy assembly both at the workshop and on site LCL Item Conveyor s thickness Roll s minimum diameter Material Tips ø x H. Stick material LCL 8S IL 4,2-7,5 110 Inox 3,4 x 16 Inox LCL 10S IL 7,0-9,5 140 Inox 3,4 x 18 Inox LCL 8S ZN 4,2-7,5 110 Zincato 3,4 x 16 Zincato LCL 10S ZN 7,0-9,5 140 Zincato 3,4 x 18 Zincato 69

7 LCL FLEX-SERIES METAL JOINTS BELT THICKNESS FROM 4.2 TO 9.5 MM. The LCL FLEX-series hinges are suitable for installation on trough belts for transportation of unpackaged products. The easy separation of plates if stressed by cross bending, and the joining made with flexible cable allow for adapting the hinge to the supporting rollers of the conveyor. The LCL FLEX-hinges are usually made of non-magnetic stainless steel and fixed by copper tips whose round cross-section gives excellent tensile stress strength. They are easy to install both at the workshop and on site with just a hammer and cut-off scissors. LCL F 8 24 Special characteristics High tensile stress strength Joint transverse flexibility Equipment and complements Staple gun plates which make installation easier and faster Terminal with 3 mm diameter hole for steel cable fixing LCL F Item Conveyor s thickness Roll s minimum diameter Material Tips ø x H. Cord material LCL F 8S IL 4,2-7,5 110 Inox 3,4 x 16 Inox LCL F 10S IL 7,0-9,5 140 Inox 3,4 x 18 Inox LCL F 8S ZN 4,2-7,5 110 Zincato 3,4 x 16 Zincato LCL F 10S ZN 7,0-9,5 140 Zincato 3,4 x 18 Zincato 70

8 LNY-SERIES METAL JOINTS BELT THICKNESS FROM 1.5 TO 2.8 MM. They are made of Nylon PA66 and are suitable to get into contact with food products of any type. They are advisable for installation on PVC, PU, polyolefin, silicone belts and on mesh conveyors. The hinge is composed of modular elements that are easily fixed by pressing a thumb and allows for joining belts of multiple width of 50 mm, also for greater widths than 2 metres. The version in light blue colour is advisable for belts in similar colour intended for transportation, selection and processing of fruits and farming products. The boxes have a monofilament of nylon to join the two dies, which allows for using the hinge in the presence of metal detectors and adhesives to install as a template for socket punching. The use of a socket punching machine is highly recommended for operators with common utilization, since it allows for precise and very fast installation. LNY Item Color Temperature C thickness Working data dan/cm min diameter LNY 30 W white - 40 / 140 1,5-2,8 8,0 60 LNY 30 LB light blu - 40 / 140 1,5-2,8 8,

9 HOW TO CHOOSE YOR LACYNG (by conveyor s thickness) HOW TO CHOOSE YOUR LACYNG (by roll s diameter) Conveyor s thickness in mm. Minimum roll s diameter Instructions for assembly and use of LB-series staple gun plates Procedure 1. Position and align the hinge on the belt in the right position. Place the belt on the plate, with the hinge aligned with the edge of the plate on the left side and bottomed out on the two stops**. Place a piece of tip set with vertical and central tips to the holes of the plate. 2. Gradually hit the staples so as to let them through the belt and then to separate the tip sets. Lastly, hit the staples all the way in. 3. Drive the punch on the last hole to the right making sure that the hinge and the belt are bottomed out on the stops. 4. Complete the application of the staples as explained in point 1 removing the punch when needed. 72

10 Instructions for assembly and use of LCL-series staple gun plates Procedure 1. Position and align the hinge on the belt in the right position. Place the belt on the plate, with the hinge aligned with the edge of the plate on the left side and bottomed out on the two stops 2. Drive the first and last staple so as to fix the belt on the plate and the drive all other staples all the way in. 3. When the belt width is greater than the length of the staple gun plate, lift the belt and move the plate to the right letting the staples through the last plate** of the hinge on the first holes of the staple gun plate. Drive the last staple and then all the other ones all the way in. Continue in the same way across the belt width. Instructions for assembly and use of the LNY-series nylon hinges Procedure 1. Cut the belt to a length of 11 mm less than the length requested, applying the adhesive strip, as recommended in the picture, on the belt surface. 2. Place the belt on a polyethylene plane and pierce with a mm diameter socket punch 3. Insert the female part of the hinge into the lower side of the belt and the male part into the top cover side applying pressure to hook the parts together. If you are not sure of the hooking, use a rubber mallet. 4. Ad Once the installation is complete, join the dies with the nylon thread. 5. Lock the ends by heating them up with a welding machine creating two stops which prevent movement. 73