YUDO BALA VALVE GATE SYSTEM

Transcription

1 BALA VALVE SYSTEM Instruction Manual YUDO BALA VALVE GATE SYSTEM Ver. 4.5 MN BALA VALVE English

2 Greetings Thank you for using YUDO Hot Runner System. YUDO fabricated Hot Runner System with its best efforts so that customers can use it most easily. However, there are many parts for customers to pay attention because it is a technical product. Please read this manual well and use it. YUDO reserves the right to change the provisions of these descriptions and specifications at any time without notification to customers. Please discuss with YUDO in advance when technical support is needed. 2

3 Contents 1. Basic Structure of YUDO Hot Runner System 1-1 Basic Structure of Cylinder 1-2 Basic Structure of Nozzle 2. Outline of Hot Runner System 3. Kinds of Hot Runner System 3-1 Open Gate, Shut Off Gate, Valve Gate 3-2 Comparison of features between hydraulic and pneumatic type in Valve Gate 3-3 Comparison of features between Valve Gate and Open Gate 4. Features and Use Effect of Valve System 5. Meaning of YUDO Open Nozzle Standard 5-1 BALA 45 Series (Valve VV Type) Specification 5-2 Shape and symbol of gate 5-3 Machining of Cylinder Part 5-4 Nozzle part machining 5-5 Gate part machining 5-6 Machining of Locating Ring Part 5-7 Machining of Lead Wire Slot Part 5-8 MODU Plate Machining (Clamping Plate, Spacer Block, Hold Plate) 5-9 Machining of Sequence System Part 5-10 Machining of Connecting System Part 6. Check Items of Hot Runner System 6-1 Check of Hot Runner System Part 6-2 Electric Check of Hot Runner System 6-3 Dimensional Check of Hot Runner System 6-4 Check items of Gate Park 7. Assembly of Hot Runner System (MODU System) 8. Operation of Hot Runner System 8-1 Installation 8-2 Caution before operation 8-3 Maintenance 9. Disassembly and Assembly 9-1 Disassembly and assembly when replacing various O rings of cylinder 9-2 Disassembly and assembly when replacing nozzle heater and T/C 10. How to Recognize Product Standard and System 11. Trouble and Countermeasure 11-1 Not being heated 11-2 Valve pin is not operating or not smooth 11-3 Occurrence of carbonization 11-4 Defect in gate mark 11-5 Resin leakage 11-6 In case that resin leaks on manifold but heater is not disconnected In case that resin leaks on manifold, heater is not disconnected, and coolant leaks to destroy insulation of heater In case that manifold heater is disconnected. 3

4 1. Basic Structure of YUDO Hot Runner System PLAN VIEW 4

5 SIDE VIEW 5

6 Hot Runner and Mold Parts List No Description No Description 1 Locating Ring 31 Gate Bush 2 Socket Head Cap Bolt 32 Cylinder Cover 3 Clamping Plate 33 Housing 4 Spacer Plate 34 Piston Out 5 Holding Plate 35 Piston In 6 Cavity Plate 36 Snap Ring 7 MODU Ass y Bolt(B2) 37 O Ring 8 Mold Ass y Bolt(B1) 38 Glyd Ring 9 Socket Head Cap Bolt 39 Wear Ring 10 Center Pin Cover 40 Valve Pin 11 Center Pin 41 Power +T/C Connector 12 Nozzle Locator 42 Solenoid Valve 13 Socket Head Cap Bolt 43 Signal Connector 14 Support Pad 44 One Touch Nipple 15 Pin Guide Bush 45 Silencer 16 Upper Insulation Pad 17 Manifold Block 18 Lock Pin 19 Socket Head Cap Bolt 20 Lower Insulation Pad 21 Dowel Pin 22 Dowel Pad 23 Manifold Thermocouple 24 Sheath Heater 25 Seal Ring 26 Nozzle Body 27 Tube Heater 28 Snap Ring 29 Nozzle Tip 30 Nozzle Thermocouple 6

7 1) Basic Structure of Cylinder The role of cylinder is very important in valve gate system. Cylinder is installed on clamping plate and is operated by signal from injection machine. Cylinder opens and closes gate by moving valve pin forward and back, which is fixed on piston. The cylinder provided by YUDO is basically for use of air pressure, and a minimum of 6bar is necessary. When it should be needed to use oil pressure, make decision after consulting with YUDO, then maximum oil pressure, must not exceed 30bar Cylinder Parts List No Description VC5804G VC6806G VC7810G 1 Bolt M6*15-4EA 2 Housing Ø 57.9*51 Ø 67.9*54.8 Ø 77.9* Cylinder Cover Ø 80*16.5 Ø 90*18 Ø 110*18 4 Snap Ring C42 C32 C42 5 Piston Out Ø 39.6*21.5 Ø 49.6*23.5 Ø 59.6* Valve Pin Ø 4 Ø 6 Ø 10 7 Piston In Ø 25.9*33.4 Ø 31.9*34 Ø 36.9*36 8 Viton O Ring ARP 221 ARP 224 ARP Viton O Ring ARP 226 ARP 229 ARP Glyd Ring GS GS GS ARP 216 ARP 222 ARP Viton O Ring ARP 115 ARP 120 ARP Viton O Ring ARP 219 ARP 223 ARP Viton O Ring ARP 225 ARP 228 ARP Viton O Ring ARP 114 ARP 115 ARP Wear Ring B=2.5 T= Viton O Ring ARP 212 ARP 212 ARP 212 7

8 2) Basic Structure of Nozzle Nozzle serves a route to feed the resin injected by injector to cavity, and is a device to maintain resin at constant temperature until it is injected. Nozzle may be used by selecting proper specification according to injection amount, and selecting proper type of nozzle according to shape or characteristics of gate part. VV Type Nozzle Parts List No Description BALA 18 BALA 25 BALA 35 BALA 45 Qty Remark 1 Cu Ring Ø t Ø t 1 2 Nozzle Ø 38 L Ø 50 L Ø 60 L Ø 70 L 1 3 Nozzle T/C NZTPIC or NZTPCA 1 Nozzle 4 HTFR1518 HTFR3625 HTFR3635 HTFR3645 Heater 1 5 Valve Pin Ø 4*L Ø 4 L Ø 6 L Ø 10 L 1 6 Valve Tip Ø 12.5*44 Ø Ø Ø Snap Ring ACRICS ACRICS ACRICS ACRICS VV Type None None None None 1 9 VA Type Ø Ø Ø Ø VAE Type Ø Ø Ø Ø VF Type Ø Ø Ø Ø LVA Type Ø Ø Ø Ø LVF Type Ø Ø Ø Ø TVA Type None Ø Ø None 15 TVL Type None Ø Ø None 8

9 3) Basic Structure of Sequence System Sequence System is a device to regulate opening and closing of gate arbitrarily, which is operated by set time on sequence timer after receipt of injection signal. When applying sequence system, it shall be determined how many zones will be controlled and how many gates will be controlled. Refer to sequence system manual for other detailed matters. Sequence System Parts List No Description Specification Q ty Remark 1 Bolt M5* Air Manifold Flat head Cap M3*8 1 3 Air Nipple PT 1/4 Coupler 1 4 Silencer PT 1/4 2 5 Sealing Plate 50*26*1.5T 1 Quantity per Sol Valve 6 Bolt M4*40 4 Quantity per Sol Valve 7 Solenoid Valve SF Sealing Plate 80, 140*45*1.5T 1 For 2, 4Zone 9 Insert (Male) 56*23*33, 72.4*23*33 1 Screw Terminal (10P 16P) 10 Bolt M4* Housing 74.5*50*52, 91*50*57 1 Use of 10P 16P 9

10 2. Outline of Hot Runner System Hot runner system is a method devised to produce product continuously without spure and runner by heating sprue and runner which serve as a route of melted resin in order to fill cavity in plastic injection mold and by maintaining it as melted state. Advantage and Disadvantage of Hot Runner System Advantage 1) Because product must be produced using 100% of new resin without any loss at all the time, defect or trouble due to foreign material can be prevented. 2) Filling up cavity is needed only, because resin is always being melted up to gate, thus the time of injection, measurement, cooling and frame opening/closing is shortened as well as the time to take out sprue and runner. 3) Improvement of product quality Because the injection pressure of injection molder is directly transferred to cavity, the problem of product shrinkage, weld, and deformation due to internal stress can be solved. 4) Increase of mechanical efficiency Efficiency of molder is enhanced because injection quantity, pressure, mold opening distance may be decreased as much as the amount of sprue and runner. 5) Extension of mold life The pressure exerted on the mold is decreased due to decrease of injection pressure and 3- stage mold of large type may be converted into 2-stage mold in case of using hot runner system, so that the trouble which can occur in 3-stage mold may be prevented. Disadvantage 1) Increase of mold cost : Hot runner components and controller are necessary. 2) Technical manpower is necessary for maintenance and repair. 3) Sufficient review is necessary for mold design depending on shape of resin and product used. 10

11 3. Kinds of Hot Runner System 1) OPEN GATE a. Direct Gate : This is the most basic system where flow route is equipped with heater. (There are BALA series in YUDO.) b. Pin Point Type Gate : Gate mark may be minimized, but a little more pressure is required. Type Basic Shape Product Shape of Gate Part Nozzle Type Direct Gate BALA TOE, TOL System Pin Point Type Gate BALA CC, CA, CF System SHUT OFF GATE a. Spring Type Valve Gate : This is the most simple valve gate system, but much injection pressure is required, so that gate mark is unstable.(there are no related products in YUDO) b. Electrical Shut off Gate : This may be mainly used for small products, but special temperature control device is required, and high technology is required for management of function.(lovo Series Nozzles of YUDO) 2)Valve Gate Hydraulic Valve Gate Advantage a. High pressure can be obtained by using relatively small cylinder. b. The life of 0 ring used is long relatively. Pneumatic Valve Gate Advantage a. Structure is simple. b. Response speed is relatively fast. c. Operation and management are easy. d. Equipment investment cost is relatively small. e. Because air is used, damaging of 0 ring does not cause contamination of surrounding. Disadvantage a. Hydraulic unit is required. b. Because oil is used, there is much possibility of oil leakage and surrounding is not clean when oiling. c. Operation and management is difficult. d. There are many elements of troubles due to carbonization of oil. e. Response speed is slow relatively. Disadvantage a. Relatively large cylinder is required. b. The life of 0 ring is shorter than hydraulic type. 11

12 3) Comparison of features between hydraulic and pneumatic type in valve gate For Valve system of YUDO, pneumatic system is used as standard, hydraulic system as special option. If you want to use hydraulic system, you should consult YUDO in advance in order to regulate system changes. The problem occurring due to misuse of hydraulic system on valve system will not covered under quality guarantee of YUDO. Even in case of using hydraulic system, YUDO standard is designed to apply 30 bar or less pressure, and is designed to be operated smoothly under maximum 30 bar or less pressure. But also, the problem caused by less than specified pressure is out of quality guarantee scope. Major specification difference between pneumatic type and hydraulic type is as follows: 1 The gap in 0 ring part which is installed on piston, cylinder, etc. is different. Drawing In case of hydraulic system In case of pneumatic system A minimum of 0.08 and a maximum of 0.13 are used for gap between piston and housing of YUDO cylinder. A minimum of 0.39 and a maximum of 0.46 are used for gap between piston and housing of YUDO cylinder. 2 Compression quantity of 0 ring installed on piston, cylinder, etc. is different. Drawing In case of hydraulic system In case of pneumatic system A minimum of 0.65 and a maximum of 0.72 are used for compression quantity of O ring used in YUDO cylinder. A minimum of 0.37 and a maximum of 0.44 are used for compression quantity of O ring used in YUDO cylinder. Maximum allowable pressure of YUDO hydraulic valve : 30 bar 12

13 3 The length of valve pin is different. In case of hydraulic valve, the length of valve pin should coincide with the normal dimension of mold. but The dimension of pneumatic valve is 1mm longer than normal dimension. There is allowance space where piston could advance 1mm more. Therefore, applying hydraulic system on YUDO system without adjusting valve pin causes damage on piston cover of gate or causes bending phenomenon of valve pin. In case of hydraulic system In case of pneumatic system The length of hydraulic valve pin should be adjusted to normal dimension. Allowance may cause damage of gate. 4 The machining angle of gate and the machining angle of valve pin nose are different. (Gate of taper type) In case of hydraulic system In case of pneumatic system 5 Gate machining shape is same in case of straight type. It is better to use straight type gate in case of using hydraulic system. In case of hydraulic system In case of pneumatic system 13

14 4) Comparison of features between valve gate and open gate Division Open Gate Valve Gate Gate Mark Drool problem - Not clean - Beautiful - There is drool problem. - It is necessary to remove the drooled resin (after pause) - Nozzle should be operated at relatively high temperature. - There is possibility of problem when changing mold. - There is no drool phenomenon Injection pressure Injection speed Resin used - Change of injection condition pursuant to gate temperature - Change of injection speed pursuant to gate temperature - Increase and decrease of efficiency pursuant to resin characteristics - Low pressure injection is possible with large gate - Decrease of twisting and stress due to decrease of stress within cavity - Constant injection speed - High-speed injection is possible. - Shortening of cycle time - Pressure compensation time may be removed or minimized. - possible to be widely used in all heat-plastic resin 4. Features and Use Effect of Valve System Valve pin may be closed while injection pressure is maintained in mold after injection and help plasticizing for the next shot material supply, then afterwards injection pressure may be transferred to cavity at the opening of gate as soon as mold closes. If the quantity and shape of molding product are composed of several different cavities or in case that large mold product is composed of several gates, it is possible to regulate filling amount of each cavity through sequence operation in order to improve or move weld line and so on. Valve gate system enables to make gate larger, so that low-pressure molding and high-speed molding are possible for this system, and molding may be performed without difficulty up to the end of product. Because gate is plugged up by valve pin, it is possible to make gate seal perfect, which enables product to gain good surface with clean gate mark, to improve product quality by decreasing of internal stress and reducing of molding deformation, and extending life time of mold. As gate may be made relatively larger, it is possible to make product thickness thin and to shorten cooling time. 14

15 5. Meaning of YUDO Valve Nozzle Standard 1) BALA Series (Valve Type) Specification BALA 18 Series Nozzle Model L HEATER MODEL T/C MODEL Nozzle Model L HEATER MODEL T/C MODEL BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] Nozzle length L : Minimum = 75mm T/C Type : IC or CA Maximum = 175mm 15

16 BALA 25 Series Nozzle Model L HEATER MODEL T/C MODEL Nozzle Model L HEATER MODEL T/C MODEL BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] Length of L : Minimum = 90mm T/C Type : IC or CA Maximum = 320mm BALA 35 Series Nozzle Model L HEATER MODEL Length of L : Minimum = 90mm Maximum = 390mm Two Heaters and Two T/C are applied for over L 320mm. T/C Type : IC or CA T/C MODEL Nozzle Model L HEATER MODEL T/C MODEL BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BALA 45 Series Nozzle Model L HEATER MODEL T/C MODEL Nozzle Model Length of L : Minimum =100mm Maximum =320mm Two Heaters and Two T/C are applied for over L 320mm. T/C Type : IC or CA L HEATER MODEL T/C MODEL BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC] BIM HTFR NZTP[CA,IC]

17 2) Shape and symbol of gate Model and Symbol Gate Shape Application BIM VV - Common gate with the widest application scope (Gate is directly machined on cavity plate) BIM VA - Insertion of gate bush into VV type - Solution of machining difficulty on gate part BIC VAE - Used for color change and the resin with large heat deformation BIM VF - Insertion of gate bush into BAC type - Used for color change and the resin with large heat deformation - Solution of machining difficulty on gate part BIM LVA - Circulation of coolant in nozzle nose - Maintenance of temperature around gate - Solution of machining difficulty around gate 3) Machining of cylinder part 1) Because the dimension around * mark is important, exact machining is required. 2) Entrance part and side part where 0 ring is inserted should be machined by taking care of roughness. If roughness is not smooth, it may cause damage of 0 ring when assembling cylinder. 3) Tolerance and dimension should be observed in order to fix cylinder exactly and to maintain valve pin protrusion quantity constant. 4) In case of gun drill type, the entrance part a where cylinder is inserted and the entrance part b in air line hole should be rounded or chamfered. If rounding or chamfering is not carried out, it may cause damage in 0 ring when assembling cylinder. a part machining detail 17

18 Cylinder Area Machining VC 58, 68, 78 (Pneumatic Cylinder) Nozzle Model VCD1 VCD2 VCD3 VCD4 VCH1 VCH2 VCH3 VCH4 VCH5 VCG1 VCG2 PCD VC VC VC VC Cylinder Area Machining VCH 78 (Hydraulic Cylinder) 18

19 Cylinder Area Machining VC 85 (Pneumatic Cylinder) Cylinder Area Machining VC 29, 35, 40, 50 (Pneumatic Cylinder) Cylinder Model VCD1 VCD2 VCD3 N PCD VCH1 T1 CT A1 A2 VCM29 GP VCM35 GP VCM40 GP VCM50 GP

20 4) Nozzle part machining 1) The part with * mark should be precisely machined. 2) YUDO requires hold plate by all means in using hot runner. Of course, there is no problem in using YUDO system by directly attaching nozzle to cavity plate. However, hot runner disambling and assembling is repeated on the way of test injection and correction of mold, this may cause of resin leakage, heater line blockage, etc. But also increase of manhour causes more cost than addition of hold plate in terms of total cost in the end, and causes drop in reliability of mold. Structure of general hot runner Structure with hold plate required by YUDO 3) Machine the space where nozzle flange part will be inserted in hold plate. 4) Machine lead wire slot. Machine heater so that lead wire may be come out of the lower surface of hold plate. Only such arrangement makes it possible to change heater directly on ianjection machine without disambling and assembling of hot runner in case of line disconnection. 5) Use M8-P1.25 tap for manifold clamping bolt. Bolt position is 68mm in manifold width direction and 60mm in length direction as shown in the drawing below. MODEL L ØD ØD1 ØD2 H1 BIM 18 V BIM 25 V BIM 35 V BIM 45 V

21 5) Gate part machining (1) VV Type Gate The most important dimension is ØD1. It is designed so that inflow of resin into heater part may be prevented by side contact of ØD1 and nozzle end part. L2 dimension is important, but there is thermal expansion, so that L2 section is not major point of resin leakage. There should be coolant hole within a maximum of 20mm from gate center. Unit : mm MODEL VVD1 VVD2 VVD3 VVD4 VVH1 VVH2 VVH3 VVH4 VVH5 VVR1 BALA BALA BALA BALA (2) VA Type Gate There should be coolant hole within A maximum of 20mm from gate center. MODEL VAD1 VAD2 VAD3 VAH1 VAH2 BALA BALA BALA BALA (3) TVA Type Gate MODEL TVD1 TVH1 TVAD TVLD E BALA 18 BALA BALA BALA 45 21

22 (4) VF Type Gate There should be coolant hole within a maximum of 35mm from gate center. Unit :mm MODEL VFD1 VFD2 VFD3 VFD4 VFD5 VFH1 VFH2 VFH3 VFH4 VFH5 BALA BALA BALA BALA (5) LVA, LVF Type Gate There should be coolant hole within a maximum of 35mm from gate center. Unit: mm MODEL LVD1 LVD2 LVD3 LVD4 LVD5 LVH1 LVH2 LVH3 LVH4 BALA BALA BALA BALA LVH5 = Cavity Thickness LVH3 MODEL Standard Length of Long Gate Bush BALA BALA BALA BALA

23 (6) VV Type Gate Machining Method a. Cut and rough the part while nozzle will be assembled on cavity plate with machining center. a part should be cut as circular machining at first so that reference may be caught during discharging machining of gate part. b part should be machined with drill or end mill as roughing concept. b. Cut the part where nozzle end part will be assembled.(c part in the drawing). Adjust depth while machining circle at machining center because this part has precise tolerance. Circle machining method is shown in the drawing. c. Machine d part by machining shape with end mill. d. Machine the gate in rough state using end mill with 0.5mm side allowance. e. Machine the gate part with electric discharge. Discharge electricity with sufficient time in order to make it smooth as far as possible because gate part is a flow route of resin. Machine the gate part with electric discharge by all means.the reasion is that precise machining is necessary to avoid gate deformation to product surface direction due to machining force in case that cavity is weak. But also when tool swings, the concentricity between c part and gate will not coincide with each other, in case that machining is performed with end mill or drill. Shape of jig for electric discharge is shown in the drawing. It is possible to maintain surface hardness of gate and to lengthen the life of gate through heat-treatment of gate surface by electric discharge machining. 23

24 6) Machining of Locating Ring Part Use of MNL 35 1 Locating ring fixes mold and nozzle locator to mold and functions as a guide to set the mold center at center of injection machine holding plate. Locating ring seat should be fixed so as not to be moved by machined hole on clamping plate by all means. And, some part(a part) of locating ring should be designed so as to be pressed by injection machine fixing plate. Fixing of locating ring with only locating ring fixing bolt may be a cause of resin leakage by injection back pressure. Moving of locating ring may be a cause of resin leakage between nozzle locator and manifold. 2 Machine locating ring seat on clamping plate. 3 Machine seat of nozzle locator on clamping plate in order to assemble nozzle locator. 4 Locating ring should be machined in accordance with specification of injection machine. 5 Refer to the drawing in the right side for machining method. 7) Machining of Lead Wire Slot Part 1 Machine the lead wire slot by selecting a hole of proper size according to wire quantity. 2 Wire surface should be prevented from being damaged by machining the solt in the proper round(minimum R10) at the part where wire slot is bent. 3 Lead wire slot should be machined differently according to quantity of wire. 4 Wire slot machining size pursuant to the quantity of wire is as follows. Nozzle Lead Wire Slot Machining Detail W = 26 W=46 DP Zone DP Zone 10 1~2 10 1~4 15 3~4 15 5~8 20 5~6 20 9~ ~ ~ ~ ~18 24

25 8) MODU Plate Machining(Clamping Plate, Spacer Block, Hold Plate) 1 Machine the guide pin hole for fixing MODU plate position. It is more advantageous to machine those 3 MODU plates and cavity plate simultaneously when machining guide pin hole. Simultaneous machining can reduce error due to machining during MODU plate assembly. 2 Machine the dimension by referring to the drawing. 3 Machine the bolt hole for fixing MODU plate. Machine the hole in clamping plate and spacer block, and machine tap in hold plate. 4 Bolt(B2) standard differs according to mold base standard. If the size of mold base is 600mm or less, install 4 or more M16 bolts ; and if the size of mold base is 600mm or more, install more than 6 units of M16 bolts or 4 units of M20 bolts. 5 Machine bolt hole(b1) for fixing MODU plate and cavity plate.machine the hole on MODU plate and machine the tap on cavity plate.follow the dimension specification for machining position and bolt specification, and the enterprise should provide exact location and specification when ordering MODU. 6 The length of ØD H7g6 part of guide pin should be H+5mm or more longer from the hold plate face(cavity plate position should be fixed in advance of fixing the end part of nozzle when assembling MODU), and the length of ØD-3 part should be fabricated 10~15mm longer than the longest nozzle(cavity plate position is guided first, rather than nozzle tip end part when assembling mold first). Otherwise, the end part of nozzle tip contacts with mold and is damaged when assembling MODU plate on mold. 7 Guide pin specification is as follows Standard used D D1 D2 D3 H H1 Mb CPN30L M6 CPN40L M12 CPN254L M6 CPN3175L M6 25

26 8 Guide pin is 10~15mm longer than nozzle to be assembled to cavity plate first, so that nozzle is guided by cavity plate. 9 Because precise fitting is made when assembling a part of nozzle, guide pin must be assembled to cavity plate first to play a role of guide. 26

27 9) Machining of Sequence System Part Machine mold by referring to the drawing in order to use YUDO sequence system. Machine clamping plate, spacer block, and hold plate after selecting solenoid valve attaching position on mold. It is more convenient to install it on the upper side of mold or to the opposite surface of worker. Refer to YUDO timer manual for detailed use method. use of 64 square Connector 16P use of 48 square Connector 10P Each of L and L1 is a dimension of position to be processed according to each zone Each of 1,2,3 and 4 zone is a quantity of hole to be processed according to each zone 27

28 10) Machining of Connecting System Part Connector is a component used to make electric connection smooth with the mold, and is essentially used in the mold equipped with hot runner system. 24P connector is used as standard connector in YUDO. It is generally more convenient to install connector at the upper surface of mold or on the opposite surface of worker. The drawing below shows on example of machining, and the machining size differs according to quantity of connector. - In processing of machining of mold, the datum base plane will be the base plane of the hold plate 28

29 6. Check Items of Hot Runner System 1) Check of Hot Runner System Part Check if the quantity of component is accurate by checking part list of the system. In the event that the quantity of component is not accurate in system assembly, the assembly schedule may be delayed due to lack of component. Especially, check if the quantities of 0 ring, pin and bolt coincide with the necesary quantities. In case of MODU type, check if the component to be assembled on MODU plate which should be is attached. (Connecting Box, Solenoid Valve, Wiring Name Plate) (1) Check if heater and T/C are properly assembled to the nozzle. Give number to heater and T/C and bind lead wire together, so as to prevent from wrong wiring, between heater and T/C wires. (2) Check if the component are attached exactly on manifold. (Upper, Lower Riser Pad, Nozzle Locator, Thermocouple, etc.) Give number to heater and T/C and bind lead wire together, so as to prevent from confused wiring. (3) Check assembly state and operation state of cylinder component. Check if 0 ring is attached to the outside in case of gun drill type, and check if nipple is attached to housing in case of nipple type. And check if snap ring is properly assembled on the upper side of housing. Wrong assembly of snap ring may cause serious personal injuries owing to cylinder cap bouncing out, when inserting air in order to check operation. Check the operation state by inserting air into air line of each cylinder. (3~4Kgf/ cm2 air pressure is proper for test.) In case of MODU type, check the operation state by connecting air line to one touch air nipple of solenoid valve. (4~6Kgf/ cm2 air pressure is proper for test.) (4) Check connecting box. Check if there is connector and solenoid valve and if the quantity is proper. Check if silencer and one touch nipple are attached to solenoid valve. 29

30 2) Electric Check of Hot Runner System Because hot runner is equipped with electric components as compared with other mold components, thorough check is necessary. Especially, the insulation state and division between heater wire and T/C wire are very important in heater part. It should be checked by all means. (1) Check of Nozzle Heater and T/C Check insulation state by connecting power line of nozzle heater to + or of tester and by contacting the other side of tester to body of nozzle. At this time, resistance should be selected for selection switch of tester. Needle of tester should not move for insulation state. Check resistance of heater and existence of line disconnection by connecting two lines of tester to power line of nozzle heater. The checked resistance value may be basis of determining capacity of heater and capacity of controller. At this time, select resistance for selection switch of tester. - Calculation method is as follows. Diagram of Ω law If the measured resistance value and the voltage are known, it may be calculated with E 2 /R. Ex) If R=60Ω E=220 V W=E 2 /R /60= W I = current (A) E = voltage (V) R = resistance (Ω) W= power consumption (W) Table:

31 Check if line is disconnected by connecting two lines of thermocouple(t/c) to + and of tester. There are ground and non-ground type in T/C. Generally, ground type is used. However, nonground type T/C should be used in case of ultraprecise injection. T/C and nozzle are grounded in case of ground type, and it is insulated in case of non-ground type. Check if T/C type is IC or CA by checking coating color of T/C. How to identify polarity of T/C is as follows. IC (J) CA (K) Division + - YUDO Sleeve Color Coating color Red stripe Yellow stripe Material Iron Constantan Yellow Magnetism Magnetic Non-magnetic Coating color Red stripe Blue stripe Material Chromel Alumel Blue Magnetism Non-magnetic Magnetic Table : 4-1 (2) Check of manifold Heater and T/C - Check insulation state by connecting + or of tester to power line of manifold heater and then contacting another side of tester to manifold block. (Same as how to test insulation of nozzle) - Check resistance of heater and existence of disconnection by connecting two lines of tester to power line of nozzle heater. (Same as how to test disconnection of nozzle) - Check existence of disconnection by connecting two lines of thermocouple(t/c) to + and of tester. (Same as how to tester disconnection of nozzle) - Check whether T/C type is IC or CA by checking coating color of T/C. How to identify polarity of T/C is as table Check resistance value by connecting power line of manifold heater to + and of tester. The checked resistance value becomes a basis to determine heater capacity and controller capacity. (Same as how to check resistance value of nozzle) The maximum value of induction controller is 15A, and maximum average capacity is proper to use up to 10~12A. 31

32 3) Dimensional Check of Hot Runner System Dimension inspection of hot runner system has close relationship with mold, and dimension measurement is used as important data when assembling mold, so that it should be exactly measured. (1) Dimension check of manifold Check manifold thickness and riser pad thickness. Manifold thickness is usually 45T(tolerance: +0.05~0), and may be 50T(tolerance: +0.05~0) in some cases. Riser pad thickness is usually 10T(tolerance: 0~-0.02) in upper side of manifold and 15T(tolerance: +0.05~0) in lower side. Tolerance scope of measured dimension including riser pad is 70T or 75T(tolerance: -0.04~+0.05). Check the distance between dowel pin center and gate center for gate position. Manifold gate distance is a dimension to consider thermal expansion quantity, so that it differ from gate distance on mold drawing. Thermal expansion quantity is calculated by using the following formula. Formula Δ L = (1.23*10-5 )*L*Δ T Δ T = (To-Tm) Δ L = Thermal expansion quantity (1.23*10-5 ) = Thermal expansion coefficient To = Manifold temperature Tm = Mold temperature L = Distance between manifold Center and gate Ex) L = 127mm To = 280 Tm = 60 Δ T = (280-60) = 220 Δ L = (1.23*10-5 ) *127*220 = mm The distance between manifold center and gate is mm. Thermal expansion quantity diagram pursuant to the length is as follows. 32

33 (2) Check of nozzle dimension - Check BALA nozzle by using the same thermal expansion quantity as manifold. - Check dimension of nozzle ØD and ØD1 part and 30mm part. - Check dimension of nozzle L1. The dimension of L1 is machined short by considering thermal expansion quantity. Because the normal dimension on the drawing is a dimension after thermal expansion, the product is as short as thermal expansion quantity. Formula Δ L = (1.08*10-5 )*L*Δ T Δ T = (Tn-Tm) Δ L = Thermal expansion quantity (1.08*10-5 )=Thermal expansion coefficient Tn = Nozzle temperature Tm = Mold temperature L = Mold size of nozzle touch part - Nozzle length, where thermal expansion quantity by model and temperature is considered, is as follows. (Nozzle length is machined as short as thermal expansion quantity based on 220 which is a temperature usually used for nozzle.) In case of using special resin, nozzle length should be adjusted by specifying injection temperature and mold temperature. [ Reference Data ] MODEL L ØD ØD1 L1(L-Δ L) Δ T:200 Δ T:250 Δ T:300 BIM18VV BIM18VV BIM18VV BIM18VV BIM25VV BIM25VV BIM25VV BIM25VV BIM25VV BIM35VV BIM35VV BIM35VV BIM35VV BIM35VV BIM45VV BIM45VV BIM45VV BIM45VV BIM45VV

34 3) Check of valve pin dimension 1 Check the size of valve pin end part according to the size of gate. The size of pin end part is smaller than gate size because valve pin is protruded 0.5mm from gate surface. Model Gate Ø Ød1 Ød ØD L1 BIM BIM ,5 2,2 BIM BIM Model Gate Ø Ød1 Ød ØD L1 BIM BIM 25 2, BIM BIM Model Gate Ø Ød1 Ød ØD L1 BIM 35 BIM 45 2,5 2,

35 2 Check valve pin length. 3 Valve pin length is checked as nozzle nominal length Spacer Block thickness + A dimension (Dimension A in diagram is a dimension including allowance stroke 1mm.) Dimension A diagram by each cylinder Ex) Cylinder : VC5504 used Nozzle nominal dimension: BIM Spacer Block : 70T =195.5mm Valve pin length is protruded 0.5mm from gate surface. (Refer to the drawing of page 5) Cylinder Model A VC5504N 30 VC6506N 30 VC8510N 36 VC58 G 30 VC68 G 30 VC78 G Check Items of Gate Part (1) Check of gate machining state (Using valve pin) Joint state of valve pin in normal state Valve pin machining angle of normal product is 38 and gate machining angle is 40. Cavity side Shape of product gate part (2) Grind the end part of pin as much as protrusion amount and make it coincide with product surface in order to make product surface coincide with the end side of valve pin. (3) Standard valve pin is delivered with protrusion quantity(0.5mm) plus 1mm allowance length. Therefore, it is 1.5mm longer than normal dimension. It is possible to cope with gate machining defect.(allowance tolerance to be handled is +0.4~-0.2mm.) (4) If valve pin joint machining angle(40 ±30 ) and gate size(øg) are improper, the following phenomenon occurs. (5) If the end part of valve pin does not reach the product surface, This occurs when gate diameter is smaller than the end part of valve pin. Cavity side Shape of product gate part - Machine gate so that valve pin may coincide with the product surface. Check the nose angle of gate and the machining angle of pin. This occurs when the gate taper angle is smaller than the taper angle of valve pin 35

36 over specified angle. Cavity side Shape of product gate part - Machine gate so that valve pin may coincide with the product surface. Check the nose angle of gate and the machining angle of pin. This occurs when the length of valve pin is short or the taper angle of gate is larger than the taper angle of valve pin over specified angle. Cavity side Shape of product gate part - Machine gate so that valve pin may coincide with the product surface. Check the nose angle of gate and the machining angle of pin. 7. Assembly of Hot Runner System (MODU System) 1) Put hold plate on assembly table, and then check the thickness ofplate and the position and size of flange part and various pins. 1 The thickness of hold plate should be ground as ±0.01 tolerance. 2 Check if flange part is properly machined. (Refer to 5-3 flange part machining) 3 Check if various pin holes are machined. (Dowel Pin, Lock Pin, Guide Pin, etc.) 4 Remove foreign material, chip and so on from frame plate. 36

37 2) Install manifold lock pin. This is easy to ignore, but plays very important roles, so this must be omitted by no means. Abnormal wear of gate and pin guide bush may be direct cause of resin leakage. 3) Measure the thickness of spacer block, and then put it on hold plate. At this time, the withdrawal groove part of lead line for manifold should be oriented upward. (Basic reason for resin leakage is determined from the thickness of spacer block.) Thickness tolerance(t) : The thickness of spacer block is the most important reason of resin leakage. Minus(-) tolerance must be maintained by all means. 4) Assemble nozzle(protrusion height : 15 mm +0.04) Give gate number to the end part of lead wire(because it is difficult in the completely assembled state), and draw it through withdrawal groove of lead wire of spacer block. Insert Cu ring into the groove of nozzle. Because the used Cu ring has possibility of resin leakage in case of re-use, replace Cu ring with new one by all means when re-assembling it after disassembly. 37

38 5) Check if dowel pin and disc are attached to manifold, and install manifold by adjusting the position of manifold lock pin.- Caution : Take care so that dust or foreign material may not inserted in the surface where manifold and nozzle contact each other. Take care so that lead wire may not be pushed between nozzle and manifold. 6) Tighten the bolt for fixing manifold. (M8 P1.25, length mm ) Give number to the end part of lead wire, and draw it through lead withdrawal groove of lead wire. At this time, bind heater wire and T/C wire together so that they may not be mixed with other wires. 7) Check thickness of clamping plate, position/size of cylinder, and so on, and then put it on spacer block. 38

39 8) Adjust the position of clamping plate, spacer block and hold plate with guide pin(2 places). Assemble guide pin and then assemble guide pin cover. 9) Fix clamping plate and hold plate by tightening bolt(b2). Block all the air hole except for air hole (2 places) in sky direction of mold.(pt 1/4 ) 10) Insert cylinder housing into cylinder hole of clamping plate. 39

40 11) Assemble the piston furnished with valve pin to cylinder housing, Push piston completely to the arrow(b) direction, check if valve pin closes gate completely in gate side, and then measure the height(a) of the upper surface of piston and the upper surface of cylinder housing. The normal dimension of a pursuant to the standard of cylinder is shown in the following diagram. CYLINDER MODEL a VC5404N 21.5 ~ 22 VC6506N 23.5 ~ 24 VC8510N 26.5 ~ 27 VC58 G 17.6 VC68 G 20.6 VC78 G ) Install cylinder cover. The bolt for tightening cylinder cover is a M5*15 range bolt. 13) Install locating ring. The bolt for tightening locating ring is a M8 range bolt. 40

41 14) Attach connector. 15) Install PT 1/4 ring elbow nipple(2 places) for air line pipe on the upper side of mold. * When transporting and handling the assembled MODU system, handle it after retreating (open) valve pin by all means. 16) Perform wiring in accordance with the following rule. The point to be considered in wiring is to check if heater and T/C to detect its temperature are coupled. Therefore, it is very important to arrange heater lead wire and T/C lead wire and give numbers before wiring. 1 The wiring diagram shows manifold shape and gate position which are seen from fixing side of mold. 2 Give gate number first to the gate which is in the center of mold. 3 Wire gate(nozzle) part first and then wire manifold when using manifold. 4 Wiring sequence : Wire gate(nozzle) located at the 1/4 quarter surface(x : +, Y ; +) in sky direction as seen from fixed side (machine nozzle side) first in counterclockwise direction according to sequence, and then wire manifold in the same sequence. 41

42 5 In case that gate is multi-point when using I type manifold, wire gate(nozzle) in operator side first when manifold is installed horizontally, and then wire it from upper side to down side according to sequence when installing it vertically. 17) Wire hot runner system at connector. Diagram Pursuant to Quantity of YUDO Hot Runner System Gate WIRING & ZONE DIAGRAMS CONFIGURATION & GATE POSITION WIRING 42

43 WIRING & ZONE DIAGRAMS CONFIGURATION & GATE POSITION WIRING 43

44 WIRING & ZONE DIAGRAMS CONFIGURATION & GATE POSITION WIRING 44

45 18) Inspect wiring state after completing wiring to connector. Wiring inspection 1 Wire the lead line of each heater and sensor at the connector in the upper side of mold according to wiring diagram, and then fix it. 2 Check if there is line disconnection or electric leakage by measuring the resistance between heater terminals at connector. Measurement method is the same as 6.2.1)2. 3 Calculate capacity of heater by calculating the measured resistance of each nozzle heater according to the method of 6.2.1)2. If the calculated capacity is the same as the capacity indicated in the following table(deviation ±10%), the wiring is normal. 4 If the checked resistance value is remarkably smaller than the numerical value in the table, there is a possibility of lead wire shorting, and so connecting of power line at this time may damage thermostat. 5 Because sensor and mold contact each other(in case of ground type T/C) in electric leakage check, there is no abnormality. 45

46 19) Assemble sequence system. 1 Insert sealing plate between solenoid valve and air manifold, and then assemble it.(m4*35) 2 Tighten blocking bolt into air manifold. 3 Assemble one touch nipple and silencer to air manifold. 4 Put sealing plate and the assembled air manifold on the mold, and then tighten it using M5*70 flat head cap bolt. 46

47 5 Connect solenoid valve magnet power cable to 10P or 16P square connector. Connection Sequence Square Connector No Sol Valve No. Connector Specification 1, 2 No.1 Sol 3, 4 No.2 Sol 5, 6 No.3 Sol 7, 8 No.4 Sol 9, 10 No.5 Sol 11, 12 No.6 Sol 13, 14 No.7 Sol 15, 16 No.8 Sol Han 10 A 250V 16A Han 16 A 250V 16A 6 Assemble the connected square connector to mold using M4*12 bolt. 7 The completely assembled shape is as follows. 47

48 20) Check item after assembling MODU system 1 Check the operation state of cylinder and valve pin with 3~4Kgf/ cm2 pressure by connecting air line. 2 Check if bolt head, cylinder cover, center pin cover, etc. is protruded on the upper side of clamping plate. 3 Check if there is no damage in assemble process at the end part of valve tip. 4 Check if opening and closing of valve gate are normal. 21) Assemble the assembled MODU system with cavity plate(mold). In order to assemble it, put cavity plate(mold) on the assembly table, remove foreign material from gate part and cavity plate, and then assemble MODU system based on guide pin. * When assembling the assembled MODU system with cavity plate or mold, assemble it after retreating (open) valve pin by all means. 22) Fix MODU system and cavity plate with bolt(b1). 48

49 8. Operation of Hot Runner System Before connecting mold to injector, check if the connector terminal wiring of controller coincides with the connector terminal wiring of hot runner mold. Check if wiring is proper and heater and T/C operate jointly by putting power to each controller, and then install mold. 1) Installation 1 Install mold on machine, and then connect the accessory assembly product of mold (cooling line, core cylinder, etc.) 2 Connect air line to solenoid(induction system is attached to connecting box). In case of sequence system type, air manifold is equipped with air nipple. 3 Connect signal line connected to injector with solenoid valve. In case of sequence system type, it is connected to timer controller case(refer to layout drawing). 4 In case of using timer unit, refer to YUDO timer manual(3. Operation pannel of timer unit SIT300). 5 Connect the trunk of controller to connecting box. At this time, fix it with care so that connector may not be moved or removed. 6 Use the controller which is suitable for the number of heaters by each system. If the connector terminal wiring of mold is different from the terminal wiring of controller, controller may be destroyed or T/C of heater may be destroyed when inputting power. Be sure to recheck it before inputting power. 49

50 7 Connect trunk to controller, turn on main switch, turn on the switch of each unit one by one and soft start function, and then check temperature change. 2) Caution before operation 1 Check if there is disconnection, electric leakage, or air leakage in heater and T/C by all means before and after installing mold on machine. 2 Check the operation state of valve pin by operating injection signal manually. 3 Start operation when there is no problem with all functions. 4 Check all the functions of mold and injector with cooling line of mold opened. In case of checking it over long time, convert the temperature of controller to preheating function. Especially, because the material which is sensitive to heat causes carbonization, care should be taken. 5 If there is no problem with mold and machine operation, check injection quantity and pin operation state by setting the temperature of nozzle 10 higher than injection temperature and injecting it one or twice with mold opened. 6 Check flow valance of raw material while injecting it over three times(short-shot) with mold closed. 7 Check the program in various products such as carbonization, gate mark, gas, etc. by injecting it at the same temperature as injection. 8 Prevent carbonization due to stay in advance by lowering the temperature of controller about 70% if it takes long time to review product.(because engineering plastic or the material with additive may be easily carbonized, temperature should be lowered by all means.) 9 Perform normal injection work. 10 In case of stopping mass production for the time being, lower setting temperature about 70% by all means. 11 If carbonization occurs, open mold immediately and purge it 3 or 4 times. 3) Maintenance Maintenance is very important because it extends the life of mold as well as the life of hot runner system. 1 When mass production is finished, remove raw material or foreign material attached to hot runner system completely. 2 Remove all moisture and oil, and spray antirust to prevent rusting. 3 Keep mold at a place where there is no moisture and ventilation is well done. 4 In case of keeping it for long time, take care so that moisture may not invade heater. Remove moisture from system. 5 When entering re-mass production, check operation state of valve pin while raising the temperature of hot runner system by 10. At this time, perform operation sequence in the same way as

51 9. Disassembly and Assembly 1) Disassembly and assembly when replacing various 0 rings of cylinder 1 In order to replace 0 ring by disassembling cylinder with mold cooled completely after injection, connect controller to nozzle and manifold first and then heat it. Heat it by setting heating temperature by 20 higher than the minimum melting temperature of resin in the nozzle. Note : Change of O rings is recommended with new ones, when it is disassembled to prevent problems caused by wearing of it. 2 Remove cylinder cover bolt and then disassemble cover. 3 Remove snap ring for fixing piston cap, and then disassemble cap. 4 Disassemble piston using the tap in the upper side of piston-out.(at this time, valve pin is disassembled together.) 5 Remove snap ring which is in the inside of piston-out using tool, and then disassemble piston-in and valve pin. 6 Disassemble housing from clamping plate. 7 Assemble it in the reverse order of disassembly. 51

52 2) Disassembly and assembly when replacing nozzle heater and T/C Disassemble from the Manifold side 1 Disassemble nozzle from mold. (Because Cu ring being assembled at the upper side of nozzle may be used only once at this time, replace it with new one during re-assembly.) 2 Fix the flange part of the disassembled nozzle to fixing jig, and then separate snap ring. 3 Disassemble heater from nozzle. 4 Disassemble thermocouple(t/c) from nozzle. 5 Assemble it in the reverse order of disassembly. Disassemble from the Cavity side 1 Disassemble MODU system only from mold.(if B1 bolt is removed, only MODU is separated.) 2 Separate snap ring from nozzle. 3 Disassemble heater from nozzle. 4 Disassemble thermocouple(t/c) from nozzle. 5 Assemble in the reverse order of disassembly. Note : Cu-ring must be replaced when it is disassembled. 52

53 10. How to Recognize Product Standard and System You can receive quicker service if you check and notify product item, standard and lot number marked on the product in case that damage, additional purchase, or customer service occurs to YUDO product. How to recognize product is as follows. 1) How to Recognize Product of Nozzle (BALA Nozzle Series) For BALA nozzle, the mark can be seen on the flange by interval of 120 interval as show n in the drawing. A drawing : YUDO Logo Marking B drawing : Product Standard Marking C drawing : LOT No. Marking 2) How to Recognize Product of Heater (Tube Type) For Tube heater, the mark is on the opposite end part of lead line as shown in the drawing. A part : YUDO Logo Marking B part : Product Standard Marking C part : Voltage and Capacity Marking D part : LOT NO Marking 3) How to Recognize Product of Manifold Block The upper side of manifold block is marked as shown in the drawing. A part : YUDO Logo Marking B part : Order No. Marking 53

54 4) How to Recognize Product of MODU System In case of MODU system, order number is marked on the ID card attached to the side of MODU plate. Name plate attaching position and order number position (A) are same to the drawing. ID Card plate attaching position on mold ID Card 54

55 11. Trouble and Countermeasure Phenomenon Cause Countermeasure and Check point A. Not being heated 1. Heater disconnection 2. Mal-contacting of trunk and connecting system 3. Mal-operation of controller 4. Change of polarity of T/C 5. Disconnection of T/C 1. Checking of heater and T/C using tester (Refer to and 3) 2-1.Checking of all the trunks using tester 2-2.Checking of connecting pin separation 3. Checking of nozzle sensor and controller sensor type (J or K) (Refer to ) 4. Controller gauge or visual check 5. No output of controller. Checking using tester.(refer to ) 2-1. Checking of all trunk 2-2. Separation of connecting pin Figure 55

56 Phenomenon Cause Countermeasure and Check point 1. Mal-connection of signal 1-1 Check signal.(dc24v, AC110,220 V) 1-2 Check if signal is sensed at signal jack using tester.. 2. Damage to piston O-ring 3. Defect in air piping 2 Disassemble and check cylinder.(refer to 9. Disassembly and assembly) 3 Check all the connections with air connected. 4. Mal-function of solenoid valve 4-1 Loosen solenoid connections a little and then check operation state. 4-2 Check if solenoid valve magnet power coincides with injector signal power.(refer to layout drawing in ) 4-3 Check if solenoid valve magnet operation valve is working. 4-4 Check if there is foreign materials in silencer. B. Valve pin is not operating or not smooth. 5. Lack of air pressure 6. The tolerance between valve pin and pin guide bush is not proper. 7. Damage to valve pin surface (sliding part) 8. Mixing of foreign material in system 9. Leakage of raw material in piston 10. Gas in resin is pushed to valve pin and pin guide bush. 5-1 Check connection state of main compressor and peripheral. 5-2 Install air booster if air pressure is 6.0kgf/ cm2 or less.(model: VABT10) 6 Remove raw material in system and then separate mold to check operation state. 7 In case of engineering plastic or a product mixed with glass fiber, disassemble it and then check sliding part. 8 Because it is located near gate in most cases, check it visually with pin operated, and then remove and disassemble it. 9-1 Disassemble and check it( Refer to 9. Disassembly and assembly) 9-2 Check pin guide bush and pin gap. 10 Check the tolerance of valve pin and pin guide bush, and then correct or change it. (This occurs mainly in PP, non- combustible resin, or engineering plastic.) 56

57 1-1 Check signal.(dc24, AC110,220 V) Figure 1-2 Check injection signal at signal jack. 4 Check the state where air is connected. 4-4 Check foreign material in silencer. 57

58 Phenomenon Cause Countermeasure and Check point C. Occurrence of carbonization 1. Overheating 2. Carbonization due to delay of raw material in cylinder itself. 3. Carbonization in delay section within hot runner. 1-1 Check carbonization part in product. 1-2 Check it around gate. 1-3 Check T/C fixing state. 1-4 Change T/C polarity. 1-5 Abnormality in controller unit defect in Triac. 1-6 Heater and T/C is changed to each other. 2 Check raw material change time in injector cylinder. 3 Check delay part of manifold and nozzle. 1-1 Checking of carbonization part around the gate of product - In case of the part near the gate as shown in the figure, it is carbonization due to delayed raw material around tip. - In case of the part far from the gate as shown in the figure, it is carbonization due to delay within injector cylinder or single V/G body. - In case of long occurrence from the gate as shown in the figure, it is carbonization due to delay within single V/G body and nozzle. 1-6 Heater and T/C are changed with each other. 58