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Model MARKETING OBJECTIVE The new Model NV 90HMC is a high-pressure type [3-1/2" (90 mm)] of coil nailer. High-pressure nailer series products have already been introduced to the Japanese market and become popular nationwide. This new product offers higher punching force about three times greater than that of conventional nailers, in order to reduce its size and weight.
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REMARK: • For more information about HANDLING INSTRUCTIONS, visit our website at: http://www.hitachi-koki.com/manual_view_export/ • Throughout this TECHNICAL DATA AND SERVICE MANUAL, a symbol(s) is(are) used in the place of company name(s) and model name(s) of our competitor(s). The symbol(s) utilized here is(are) as follows:...
1. Safety Instructions ----------------------------------------------------------------------------------------------- 8 TROUBLESHOOTING GUIDE -------------------------------------------------------------------------------------------- 10 1. Troubleshooting and Repair -------------------------------------------------------------------------------- 10 2. Possible Causes and Corrections of Air Leakage------------------------------------------------------ 15 REPAIR GUIDE---------------------------------------------------------------------------------------------------------------- 18 1. Precautions on Disassembly and Reassembly --------------------------------------------------------- 18 Assembly Diagram for NV 90HMC...
Powerful punching force about 1.3 times greater than that of our conventional NV 90AH Nailer. High pressure nailer Conventional nailer High pressure nailer Model NV 90HMC NV 90AB Weight 2.5 kg (5.5 lbs.) 3.0 kg (6.6 lbs.) 2.5 kg (5.5 lbs.) Height 322 mm (12-11/16”)
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Dual action trigger This function automatically switches between "Single sequential actuation mode" and "Contact actuation mode" according to the operation sequence. This function can prevent unwanted double firing in "Single sequential actuation mode." Tool-less adjuster Rotating this adjuster adjusts the nailing depth (sink quantity of the nail head). Shallow Deep Adjuster...
The air plug of the Model NV 90HMC is exclusively designed for high pressure and cannot be connected to any air hoses and compressors that are generally used at much lower air...
2. Nail Selection The Model NV 90HMC utilizes common wire-collated and sheet-collated nail coils of 150 to 300 round-head nails. Applicable nail dimensions are shown below. However, genuine HITACHI nail coils should be used to assure satisfactory nailing quality. CAUTION: Ensure that nails are as specified in Fig. 1. Using other nails will cause nail jams and consequent nailer damage.
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Fig. 2 • Required nailing energy and nailer output energy Required nailing energy Nailer output energy...
• Note that when you raise the Model NV 90HMC from the floor (after pressing the pushing lever against the floor) with the trigger pulled, single sequential actuation mode is automatically selected. Therefore, nails are not punched even when you press the pushing lever against the workpiece.
COMPARISON WITH SIMILAR PRODUCTS 1. Comparison of Specifications (Superior specifications: HITACHI Maker Model NV 90HMC NV 90AB (High pressure nailer) Item (High pressure nailer) (Conventional nailer) 12 to 23 bar 4.9 to 8.3 bar 12 to 23 bar Operating pressure (12 to 23 kgf/cm (5 to 8.5 kgf/cm...
1. Safety Instructions In the interest of promoting the safest and most efficient use of the Model NV 90HMC Nailer by all of our customers, it is very important when concluding a sale that the salesperson carefully ensure that the buyer seriously recognizes the importance of the Instruction Manual, and fully understands the precautions listed on the Warning Label attached to each tool.
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(320 psi, 23 bar) or less. (2) If the dust in compressed air accumulates on the sliding portion, the Model NV 90HMC will not operate properly. Lubrication effectively removes dust and also prolongs the service life of the Model NV 90HMC in terms of maintaining good performance.
TROUBLESHOOTING GUIDE 1. Troubleshooting and Repair Possible cause Problem Inspection method Corrective action ( *: Most-common cause) <Nails> Nails cannot • Magazine is not loaded • Check that the magazine • Use specified nails. be punched. with specified genuine is correctly loaded with •...
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Possible cause Problem Inspection method Corrective action ( *: Most-common cause) • Air leaks from the gap • Tighten screws and check Nails cannot between the body and the the O-rings. be punched. nose. (continued) • O-rings are worn or •...
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Possible cause Problem Inspection method Corrective action ( *: Most-common cause) • Cylinder inner surface is • Check that nails can be • Remove dust and then Nails cannot abnormal (packed with punched at 4.9 bar (5 lubricate. be punched. dust or worn).
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Possible cause Problem Inspection method Corrective action ( *: Most-common cause) *• Driver blade is worn. • Perform idle punching to • Replace the part. Nails cannot check whether the driver blade protrudes from the completely nose tip. punched *• Piston O-ring is abnormal •...
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Possible cause Problem Inspection method Corrective action ( *: Most-common cause) <Body: Nail feeding is Nails jam. incomplete.> (continued) • Feeder is worn and the • Open the nail guide and • Replace abnormal parts. sliding section abnormal. check the position of the •...
2. Possible Causes and Corrections of Air Leakage 1. Air leakage repair location • Air leakage repair location Control valve section Magnified view of B Section of A - A -15-...
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(3) Next, check the other possible parts. [Bold] numbers in the description below correspond to item numbers in the Parts List and exploded assembly diagram for the Model NV 90HMC. Possible causes Air leak point...
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Possible causes Air leak point Control valve OFF Control valve ON Control valve Defect on O-Ring (P7-U) [89] of Valve Defect on O-Ring (1AP-11) [92] and O- exhaust port Piston [91] (worn, cut or flaws) Ring (P9-U) [90] of Valve Piston [91] Defect on O-Ring (I.D 1.8) [94] of Plunger (worn, cut or flaws) [95] (worn, cut or flaws)
The following describes the most essential precautions on disassembly and reassembly of the nailer. The NV 90HMC Coil Nailer mainly consists of six sections: output section, air duster valve section, control valve section, magazine section, nail feeder section and cap section.
Disassembly and Reassembly of the Output Section 1. Disassembly and reassembly of the Upper Cover Exhaust Cover Piston (H) cylinder ass’y [Tools required] • Hex. bar wrench (4 mm) Seal Lock Hex.Socket Flat Hd. Bolt M5 x 10 [1] • Phillips screwdriver •...
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• First mount the Cylinder Plate [38] on the • Reassembly of the cylinder ring Cylinder Ring [40], and then place the thinner part over the air hole of the Cylinder [36]. Cylinder [36] Air hole Cylinder Ring [40] • Be sure to first mount the Valve Plate [24] on •...
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Disassembly and Reassembly of the Air Duster Valve Section [Tools required] • Socket wrench (14 mm) • Flat-blade screwdriver Retaining Ring (E-Type) For D4 Shaft [34] Valve Bushing [33] Knob [35] (left-handed thread) O-Ring (S3) [32] O-Ring (1AP-3) [30] O-Ring (S-10) [31] Plunger [29] Upper Cover [5] Plunger O-Ring [28]...
Disassembly and Reassembly of the Control Valve Section [Tools required] • Roll pin puller (ø 3, ø 2.5) • Flat-blade screwdriver O-Ring (S-14) [86] Feeder Shaft Ring [41] O-Ring (S-16) [87] Machine Screw (W/Washers) Valve Bushing (B) [88] M5 x 25 (Black) [105] O-Ring (P7-U) [89] Roll Pin D3 x 28 [100] O-Ring (P9-U) [90]...
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(2) Reassembly Conduct reassembly by reversing the disassembly procedure, but note the following: (a) Reassembly of the control valve section • Always keep the control valve section clean. • Fully apply grease to the O-Ring (S-16) [87], O-Ring (1AP-5) [96] and O-Ring (S-6) [97] of Valve Bushing (A) [98], O-Ring (I.D 1.8) [94] of the Plunger [95], O-Ring (P7-U) [89], O-Ring (P9-U) [90] and O-Ring (1AP-11) [92] of the Valve Piston [91], and O-Ring (S-14) [86] and O-Ring (S-16) [87] of Valve Bushing (B) [88].
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(b) Reassembly of the Trigger section • Reassemble Trigger Arm (C) [67] with its protrusion facing upward. • Reassemble the Roll Pin D2.5 x 16 [72] with its splitting oriented as shown below. • Reassembly of the Trigger section Protrusion of Trigger Arm (C) [67] Trigger Piece (C) [65] Trigger [68] Roll Pin D2.5 x 16 [72]...
Disassembly and Reassembly of the Magazine Section 1. Disassembly and reassembly of the magazine ass'y [Tools required] • Disassembly and reassembly of the • Flat-blade screwdriver magazine ass'y • Phillips screwdriver • Roll pin puller (ø 4, ø 2.5) • Hex. bar wrench (4 mm) •...
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• Disassembly and reassembly of the magazine section Body Ass'y [42] Machine Screw (W/Washers) M5 x 25 (Black) [105] Nylon Nut M5 [134] Warning Label [139] Pin [140] Magazine [137] Feeder Shaft Ring [141] Nylon Nut M5 [134] Pin [140] Magazine Cover [142] Sleeve [135] Pushing Lever...
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2. Disassembly and reassembly of the Nail Holder , the Holder Shaft , etc (1) Disassembly • Pull out the two Pins [140] by using the roll pin puller (φ4). The Magazine [137] and Magazine Cover [142] can then be removed. •...
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Disassembly and Reassembly of the Nail Feeder Section [Tools required] • Hex. bar wrench (5 mm ) • Roll pin puller (ø 4, ø 2) • C-shaped snap ring puller for hole Retaining Ring For D24 Hole [114] Body Ass'y [42] Feed Piston Cover [113] O-Ring (1AP-3) [106] Bumper [112]...
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1. Disassembly and reassembly of Nose, Pushing Lever (A), etc (1) Disassembly • Remove the four Nylock High Tension Bolts M7 x 25 [56]. The Nose [47] and Pushing Lever (A) [59] can then be removed. • Remove the Shaft Ring [117] of Nose Piece (A) [122] by using the slotted screwdriver. You can then detach Nose Piece (A) [122], the Nose Shaft [119], two Nose Sleeves [118], Spring [121], Urethane Shaft [120] and Nose Bumper [116].
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3. Disassembly and reassembly of the Piston Bumper, Feeder (A), Feed Piston, etc (1) Disassembly • Remove the Nose [47] and push the lever components from the output section according to item 1 in "Disassembly and Reassembly of the Nail Feeder Section". You can then remove the Piston Bumper [45].
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4. Disassembly and reassembly of Nail Guide, Nail Stopper (A), Nail Stopper (B), etc [Tools required] • Flat-blade screwdriver • Hex. bar wrench (3 mm) (1) Disassembly • Remove the Shaft Ring [117] of the Nail Guide Shaft [57] by using the slotted screwdriver, and then pull out the Nail Guide Shaft [57].
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Disassembly and Reassembly of the Cap Section [Tools required] • Wrench (width: 21 mm) (1) Disassembly Dust Cap [63] • The Cap [62] is unified with an Cap [62] M42 left-handed thread and (left-hand thread) can be removed by using a wrench.
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LIST NO. E061 PNEUMATIC TOOL PARTS LIST HIGH PRESSURE COIL NAILER 2009 12 11 Model NV 90HMC (E1) 67 71...
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PARTS NV 90HMC ITEM CODE NO. DESCRIPTION REMARKS USED 887-128 SEAL LOCK HEX.SOCKET FLAT HD. BOLT M5 X 10 885-264 WASHER 886-890 PROTECTOR 885-854 NYLOCK BOLT M5 X 65 886-901 UPPER COVER 886-898 HEAD BUMPER 886-904 HEAD GUIDE 886-902 PACKING (B)
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PARTS NV 90HMC ITEM CODE NO. DESCRIPTION REMARKS USED 949-498 ROLL PIN D4 X 18 (10 PCS.) 883-144 FEEDER ARM (B) 883-143 FEEDER SPRING 886-886 FEEDER (A) 883-093 PLUNGER (B) 993-040 NYLOCK HIGH TENSION BOLT M7 X 25 883-091 NAIL GUIDE SHAFT...
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