JH21 Power Press (Pneumatic Press) Operation Manual

This is one complete JH21 power press service manual, it will teach you how to install and operate the press properly.

Keep reading:

I Summary

  1. Working Principle and Application of Punch Press Machine
  2. Working Environment and Conditions

II Specification

III. Preparation before the operation

  1. Construction and Adjustment of Principle Units
  2. Frame
  3. Driving Parts
  4. CIutch and Brake
  5. SIide
  6. Hydraulic Overloading Protector
  7. Pneumatic System
  8. Lubrication

VII. Foundation plan

VIII. Installation and testing

  1. Installation of Punch Press
  2. Installation of Moto
  3. Horizontal Adjustment
  4. Installation of air pipeIine
  5. Testing
  6. Operation Preparation
  7. Running Preparation
  8. Operation Preparation
  9. Start and Stop of Main Motor
  10. Daily checkup
  11. Maintenance and Safety

XII. Troubles and Remedies

XIII. Easy wearing Parts List

XIV. Attached Figures

  • Figure 1 Product Structure
  • Figure 2 Frame
  • Figure 3 Driving Parts
  • Figure 4 CIutch and Brake
  • Figure 5 SIide
  • Figure 6 Pneumatic schematic diagram
  • Figure 7 Lubrication schematic diagram
  • Figure 8 Foundation plan
  • Figure 9 Front Main Shaft Bushing
  • Figure 10 Back Main Shaft Bushing
  • Figure 11 Connection bottom bushing
  • Figure 12 Connection upper bushing

This manual aims at the main performance characteristic, operation notice. The Figures are only for reference. The products are based on real presses.

punch press

I. Summary

Working Principle and Application

JH21-80Ton (800kN) Open back fixed bed punch press, adopting longitudinal crankshaft and taking crankshaft rod construction as the working mechanism.

By the two-stage speed reduction of the motor, the crankshaft will rotate, then the crankshaft connection rod will drive the slide to do reciprocating motion.

The driving system is closed completely.

The press adopts pneumatic clutch and brake, which makes the punch press work stably and the slide be stopped at any position.

It is the universal press for sheet punching and pressing, and is suitable for cutting, punching, blanking, bending, drawing, and stretching but except for coining.

The nominal pressure of the press is 800kN. The normal pressure stroke is 4.5mm.

The user should choose the pressure force according to the following graph.

In operation, the crossing of working pressure and its angle of crank must not exceed the range indicated by the pressure curve.

Otherwise, it will harm the press.

pressure graph

Working Environment and Conditions

In order to make the press work normally, reduce the frequency of maintenance and assure the service life, it cannot be used in the environment of wet, aggressive gas, liquid and explosive gas.

The air pressure cannot be less than 0.6 MPa.

The voltage is 380±38V and the frequency is 50±5Hz.

II. Specification

No. Item Value Unit
1 Nominal Pressure 800 KN
2 Slide Stroke 130 mm
3 Stroking of nominal pressure 4.5 mm
4 No. of Slide Stroke 60 SPM
5 Max Die Space (Adjustment Up, Stroke Down from Bolster to Bottom of the Slide 330 mm
6 Die space adjustment 80 mm
7 Distance between slide center and frame 310 mm
8 Bolster Size (FB x LR) 600×1000 mm
9 Slide Surface Size (FB x LR) 460×540 mm
10 Stem Hole Size Φ50×80 mm
11 Thickness of Bolster 140 mm
12 Distance between Uprights 600 mm
13 Air Cushion (Special Order)
Max Stroke of Air Cushion
65 mm
Max Pressure 80 KN
14 Main Motor Model Y132M-4
Power 7.5 KW
15 Overall Dimension
F.B. 1711 mm
L.R 1210 mm
Height 2895 mm
16 Overall Weight ≈6749 kg

III. Preparation before Operation

In order to make the punch press work in the best status, the user should use the press properly and calculate and refer to the following items before operating the press.

Rated Load Capability

The working load should be limited under the nominal pressure strictly.

The overloading protector prevents overloading caused by mis-punching or sheet of non-uniform thickness in the process.

It is wrong to use press with random overloading and easy to damage presses.

So it is very important to calculate the working load before working.

Torque Capability

The punching force will be changed with the change of slide position.

You should use the press according to the stroke pressure graph which shows this change.


Stick will happen if the working pressure exceeds the rated torque. Besides that, the punch press machine will be stuck if applying load before the clutch is engaged.

This phenomenon will do harm to the clutch.

So, you must stop the punch press machine before in the course of processing immediately if it happens and take measures to prevent happening next time.

Eccentric Load

In principle, it must be avoiding the eccentric load that will cause non-parallel between the lower surface of the slide and the bolster, and uneven force to slide gib which will infect the precision.

If not, please do it according to the figure of allowable distance that the load center deviates from the bolster to assure precision and safety.

working pressure

Single Turn on Frequency

In order to make the punch press work in the best status and assure the service life of the clutch and brake, please work according to single turn on time listed in the main specification of the press.

It will cause abnormal wear of the clutch and brake and failure if exceed the single turn-on time.

The single turn-on time of this press is not more than 25/minute.

IV. Construction and Adjustment of Principle Units

Frame (Figure 2)

The welded frame adopts high-strength steel. The slide moves to and fro inside the gibs.

The screw of the right side frame is used for adjusting the clearance of the gibs and slide.

The adjustment of the knockout rod will make punched parts be pushed down when the slide approaches the top dead center.

But, if should care not to make the stripper touches the bottom of the slide knockout rod groove to avoid an accident.

The bolster of the frame is the basic measurement of precision.

It should maintain the surface roughness and flatness for avoiding the smash, hit and scratch of tools and cutting tools.

Driving Parts (Figure 3)

The main motor drives the flywheel by the V belt and makes the energy be saved in the flywheel then transmitted to the gear shaft by the friction clutch and brake.

The gear shaft will drive the big gear dipped in oil bath, then the big rear will drive the crankshaft to make the slide move up and down.

V Belt adjustment: First unscrew 4 locknuts, then turn equally 4 adjusting screws.

The motor bracket will be adjusting up and the belt could be adjusted.

When the v belt is straightened, press about 2 kg forces on the center of the V belt, and the belt will bend to 10 mm of proper tension.

After adjustment, tighten the 4 locknuts. The new v belt will work stably after used for several days.

Adjust the V belt again if necessary. The v belt should be kept in the cool and dry place, and avoid light and oil

When replacing the V belts, first unscrew the adjusting screws, loosen the belt, and uninstall the clutch brackets, and pull out the belt.

It is very necessary to change all belts to new ones.

Using new and old ones simultaneously will cause the service life reduction of belt for different tension.

These old V belts Gan cooperate with other old ones. In addition, it is noticeable that belts of the same nominal dimension maybe have length variance of several centimeters.

So, the belts of the same group should be the same length.

Auto Feeding. Shaft End: If users need auto-operation, they can assemble the auto feeder to the output shaft of the frame face. (Output shaft is for special order. Ordinary products do not have)

Clutch and Brake (Figure 4)

This punch press adopts pneumatic friction clutch and brake which is assembled in the inner cavity of the frame. (Refer to the clutch manual)

Slide (Figure 5)

The slide is one of the key parts of the presses. Its precision directly influences the precision of presses.

This punch press adopts square hexagonal long gibs which can attain good precision and stability.

The connection rod and ball-head screw are components that change the rotation motion to reciprocating motion.

The lower end of the ball-head screw touches the ball-seat There is the hydraulic overload protector under the ball-seat.

The protector could exhaust the oil in the hydraulic die cushion in about 1/100 second, then at the same time send out electric signal and make the press stop emergent for assuring the safety of die and press.

After the failure is eliminated and the slide moves back to top dead center, the hydraulic die cushion will rebuild the pressure automatically.

Then the punch press could go on working.

Users can adjust the die height. Please refer to the relative operation of electrical parts of the service manual.

There are shims in the connection rod and cap.

After long time operation, the clearance of the crankshaft and bushings will be increased.

Users can take out shims to adjust the clearance of the crankshaft and bushings. (Normal clearance: 0.08-0.13mm)

4.1 Clearance Adjustment between slide and gibs

The distance between the slide and gibs must be appropriate.

It will make the slide run smoothly and reliably. If necessary, it should be adjusted properly with the following procedure.

(1) Loose the screws on the gibs and loose the set screws on the right side of the frame.

(2) Adjust the left side gibs and tighten the screw.

(3) Adjust the right side gibs, and choose the shims according to the clearance for the decision of taking out or increasing.

After adjustment, tighten the front screws and right-side set screws.

(4) The clearance between slide and gibs should be 0.03-0.05mm, but the total allowable value of front and back contact surface clearance should be 0.04-0.0Bmm.

Usually, the clearance between the upper and lower ends is large.

When the depth of the thickness gauge is above 30mm, the measured value is right.

Note: 0. 03mm gauge in, 0. 05mm gauge not in。

(5) When all is adjusted, check the clearance of every part. If not right, re-adjust it.

4.2 Slide Knock-out Device

The knockout force is 5% of nominal pressure.

4.2.1 Structure of slide knockout equipment

(1) Be combined the knockout rod, knockout seat and knockout bar.

(2) Knockout bar is set above the central line of the slide, which crosses the slide.

(3) When the slide rises, the knockout bar touches the knockout rod, which ejects out the punched parts.

4.2.2 Operation and Adjustment of Slide Knockout Equipment

(1) Unscrew fix screw of the knockout rod, and adjust the knockout rod to the proper position. It is noticed that knockout rods of left and right sides should be with the same height.

(2) After adjustment, retighten fixed screws.

(3) When using the knockout bar, the touch of the transverse bar and slide will cause noise.

4.2.3 Notice

When the user changes the die, it should be noticed that before adjusting the height of the slide, raise knockout rod to the highest position to prevent striking the knockout rod when adjusting die height.

Adjust the position of the knockout bar, which could make material being pushed when the slide moves close to the top dead center.

But don’t let the knockout bar touches the bottom of the knockout slot for fear of an accident.

4.3 Counter

The counter installed in the electric panel is used to calculate and display the cumulative number of strokes.

When the slide moves up-and-sown once, the counter will take count of 1.

lf it need be reset, press the reset button.

The counter can calculate the production output.

4.3.1 Panel of Counter

Panel of Counter

4.3.2 Operation Method

(1) Push the switch to OFF, the counter will not work.

(2) Push the switch to ON, and the counter will work.

  • Notice

When resetting the counter, it must stop the slide in the top dead center.

If reset the counter when the punch press is still working, it is possible to damage the counter.

Hydraulic Overload Protector

The hydraulic overload protector could auto=detect the oil pressure of the oil hydraulic cylinder in the slide.

When the oil pressure is not enough, it could supply the pressure quickly to maintain the normal work ability.

When the overload caused by mis-punching and uneven thickness of the sheet in the process happens, the protector can unload immediately to protect the service life of accessories and die.

The hydraulic overload protector consisted of the pressurized cylinder, pressure relieve valve and inductive switch.

5.1 Preparation before operation of Hydraulic Overload Protector

  • Check the oil level and check if there is enough oil in the air pump. If oil is not enough, loose the screw of pouring orfice and charge antioxidant pickling hydraulic oil (ISO VG-32) or other hydraulic oil of the same performance.

oil box

  • Make sure of air gage is normal.
  • If the slide stops at the top dead center, press the reset button, then air operated pump will start working. In about 1 minute, oil pressure will reach the specified value, the air pump will stop.
  • If the slide does stop at the top dead center, please operate with the following procedures:

① Push operation mode to “INCH” stroke.

② Press the operation button, inch stroke the slide to stop at the top dead center. (If the die has been installed, please pay attention to the working height of the die to assure safety)

③ When the slide arrives at the top dead center, press the reset button, and the air pump of the overload protector will start working. about 1 minute, the pressure will reach a specified value and the air pump will stop automatically, and the overload indicator light will go out simultaneously.

④ The single and continuous operation modes can be used when the overload indicator light goes out.

⑤ Operation preparation is complete.

(6) Air elimination of oil pressure cushion in the hydraulic overload protector

If there is air in the oil pressure cushion, the function of the hydraulic overload protector will not work well and make the air pump work ceaselessly.

The method of air elimination:

① Stop the slide at the top dead center.

② For safety, stop the main motor. After the flywheel stop completely, reverse the screw of the oil drainage hole on the hydraulic overload protector with the hexagonal spanner and the oil will flow out.

③ If the oil flows out brokenly or with bubbles, it shows there is air interfused.

When the oil doesn’t flow out brokenly or without bubbles anymore, tighten the screw of the oil drainage hole. Check whether there is gas leaking from the joint between the pump and end plane of the oil box and if the oil pipe blow.

air elimination

④ Air elimination is complete.

(7) Reset of Hydraulic Overload Protector:

If the punch press overloads, the overload indicator will light.

Operate it according to step (5)

5.2 Maintenance of overload protector

(1) Periodically check whether there is gas leakage from the tube connecting to the safety valve.

(2) Periodically clean the oil filter.

(3) Periodically check whether bolts of connecting part are loose.

(4) Periodically check the oil in the box is enough or not.

(5) Periodically check whether the electromagnetic valve is normal or not.

5.3 Common Failures and Trouble Shooting of Hydraulic Overload Protector

NO. Failure Status Source of Failure Solution
1 The pneumatic oil pump doesn’t work 1.  Air source failure 1.  Elimination
2.  Air leaking in pneumatic tube 2.  Change
3.  Electromagnetic valve failure 3. Maintain, chean and change
2 The pneumatic oil pump works ceaselessly for a long time 1. Air interfusing in the system 1. Air exhaust
2. Oil leakage in the connecting system of the external tube 2. Maintenance
3. Port of safety protection valve is blocked 3. Disassemble, check and clean
3 The pneumatic oil pump works but cannot builds pressure 1. Seal ring of pneumatic oil pump piston rod is damaged 1. Change the seal ring
2. High-pressure seal ring of pneumatic oil pump is damaged 2. Change the seal ring
4 The pneumatic oil pump doesn’t work after air charging but exhaust air from the port 1. Valve core of pneumatic oil pump is blocked 1. Repair
2. Valve core of pneumatic oil pump is blocked by feculence 2. Disassemble, check and clean

V. Pneumatic System (Figure 6)

The solenoid valve is the main executing component and has the self-control function.

When one valve could not work normally, the other valve will exhaust and make the clutch disengage, the slide will stop working to make sure of the safety of people and press.

The pressure of the air source should range from 0.55 to 0.6MPa.

And it should notice to adjust the pressure to the specified value; the lubricator should maintain a certain oil level.

The gas filter and air reservoir should often drain water and contamination.

Air consumption of punch press and compressor

JH21-80 clutch air consumption: 0.18m3/min. It is suggested to select 0.3m3/min compressor for the single press.


(1) When adding oil to the lubricator, the air pressure in the pipeline must be released to avoid an accident.

(2) The pressure of the counterbalance cylinder and the weight of the upper die could be adjusted according to the following figure. The maximal allowable working pressure of the counterbalance cylinder is 0.8MPa.

The pressure for counter balance cylinder

(3) The electric relay interlocks with the electric circuit. When the pressure is too low, the circuit will not work. The pressure relay has been adjusted before leaving the factory; users should not adjust it randomly.

VI. Lubrication (Figure 7)

The punch press machine adopts intermittent auto lubrication system and manual oiling lubrication.

The oil is pumped to all lubrication points through the oil-promoting distributor.

The flywheel rolling bearing, rotating joint and air cushion are lubricated by oil gun.

The lubrication system is very important to the crankshaft press.

Through lubrication, it can reduce the wearing of accessories, increase the service life, assure precision, and reduce the power consumption and maintenance fee.

So except for the friction surface of the friction clutch anti brake, ·all parts in relative motion must be lubricated.

① When operating the press, it should notice the lubrication effect to prevent the oil way jamming.

Prevent the main bush, connecting rod bearing and slide gibs from being heated and burned.

The temperature should not be over +70°C and rising, temperature Should not be over <+-35°C.

It should stop the punch press machine once heating. the temperature of the main motor can not be over +60°C (Measure the cover of the motor).

② Replacement of lubrication oil in the gear case:

It should replace the lubrication oil for the first time after 3 months (about 750 hours) use.

After that, it should replace the lubrication oil once every 6 months and clean the gear case every 6 months (about 1500 hours).

③ The lubrication of the flywheel bearing and driving shaft bearing is enclosed type, fill the grease before assembling.

It should fill the lubricating grease once (3# lithium grease) every 2 months, and check for once every half year.

When filling the grease to the bearing, fill about 60-70% between the flywheel and the bearing.

④ The counterbalance cylinder adopts lubricated air lubrication and oil hand gun lubrication.

⑤ In order to assure the lubrication of the ball screw and ball seat, it should add 100ml 20# oil before testing after the installation.

⑥ Lubricator: Add 20# oil to the lubricator and check it every week


Lubrication and oil changing should refer to the lubrication direction on the press.

Lubrication on working:

  1. First, start the main motor, the lubrication pump will work and operate the press after 5 minutes.
  2. The punch press machine should go into production after the main motor runs for 10 minutes when the press stops working for 24 hours.

Lubricating Oil Box:

Check the lubricating oil box every day and fill the oil according to the need.

During the initial installation period, the requirement of oil is large and it should fill the oil in time.

Manual Oiling:

It must cut off the power when manually oiling.

Oil Change:

It should fully clean the interior of the oil box and tube when changing oil.

Lubricating chart:

NO. Lubrication Point Brand and Type of Lubricating Oil Lubricating Mode
1 Connecting Rod bushing 00# Lime Grease Power-driving Lubrication
2 Front Main bushing 00# Lime Grease Power-driving Lubrication
3 Back Main bushing 00# Lime Grease Power-driving Lubrication
4 Gib (6 points) 00# Lime Grease Power-driving Lubrication
5 Connection thread CKC150 Gear Oil Manual Oil gun Lubrication
6 Ball Screw CKC150 Gear Oil Fill oil lubrication
7 Gear Box CKC150 Gear Oil Dip lubrication
8 Balancer HL150 Lubrication Oil Manual Oil pump Lubrication
9 Manual Oil Pump HL150 Lubrication Oil
10 Grease pump 00# Lime Grease Electric lubrication
11 Air Cushion Lubricating Points 2# Lithium Grease Manual Oil gun Lubrication
12 Flywheel Bearing 2# Lithium Grease Manual Oil gun Lubrication

VII. Foundation plan (Figure 8)

Preparation before construction

1.1 Dig according to the foundation plan.

1.2 If the soil is soft, it must pile driving to strengthen. (The pressure of soil should

not be less than 8 ton/m’)

1.3 Lay the rubbles on the bottom to the height between 100mm and 200mm.

1.4 Preserve the holes in the base when filling concrete.

  1. Prepare the concrete according to the foundation plan.
  2. After the concrete drying, take off the wooden sheet
  3. When installing the punch press machine, it should assemble the press machine, anchor bolts, and horizontal adjusting plate in the pit. After adjusting the press horizontally, fill the concrete into anchor bolts pit.
  4. Repair it after drying.

(1) The footplate around the punch press machine should be prepared by customers with proper materials.

(2) If need the shockproof, it should add fine sand stone layer about 150mm wide around the foundation.

VIII. Installation and Testing

Before adjusting, it must understand the structure of the press in detail.

Installation of press

  • Please prepare the foundation according to the foundation plan. If the soil is soft, please strengthen and iron reinforcement properly.
  • When the press enters the factory, put the press in a dry place for several days, checking the electromotor and transformer. And then start to install.
  • The punch press is coated with rust preventing oil on the way of transport. It should wipe off the oil before installation. Especially the oil on the surfaces of the gibs and friction surfaces must be cleaned.
  • Please measure the levelness of the press with a precision leveler. The foundation bolts will be fixed only when the level meets the requirement.
  • When adjusting the press, it should notice that the levelness is 0.3/1000 mm. Please confirm whether the bolster is fixed before measuring the levelness
  • If users choose to install bolster by themselves, it should notice to keep the interface between bolster and working table clean. Don’t leave paper, metal scrap, gauge, washer, dirt between bolster and working table.

Installation of motor

The main motor is usually installed on the punch press machine. If the motor must be disassembled on the way of transport, please reinstall it as the followings:

  • Unpack the package and check whether the accessories are damaged.
  • Clean motor, belt pulley, flywheel groove, and bracket. Don’t make liquor drop into the electromotor. It must clean V belt with cloth but not cleaning liquid.
  • Install the motor to the joint position, but don’t lock the screws completely. It should notice to support the weight of the motor with the sling before locking screws.
  • Measure the reference line of the belt pulley groove and flywheel groove, and move the motor to the reference line correctly.

If the reference-line belt pulley groove and flywheel groove is not matched, it will damage to belt groove and bearing of the motor.

If the reference line of belt pulley groove and flywheel groove is not matched, it will damage to belt groove and bearing of the motor.

After adjusting the reference-line, tighten the screws of the bracket of the motor.

  • Move the motor to the flywheel and don’t make V belt building up strains when V belt sliding in the block.


Don’t force the belt to enter into the groove.

After installation, the tension belt should be about 10mm when pressing it with the thumb.

Horizontal Adjustment

Levelness of bolster is very important. Most of the presses are installed with bolster.

But before measuring, it must check whether the screws are locked.

  • First, clean the bolster.
  • Place a precision level gauge on the bolster for the front, middle and back measuring.
  • Shims may be used to adjust the levelness frame.


① The shims must be as large as the foot of the press which could make the foot interface bear weight evenly.

② It must check up the levelness one month later. If the error appears, readjust the levelness. Check other items once every half year and assure the levelness of the press, which could maintain good performance of the press.

Installation of air pipeline

The airline should be connected to the back of the press. The required air pressures

are 0.6MPa. But the distance from the air source to press should be within 5 meters, and the diameter of the pipeline cannot be less than1 “.

The dust and sewage should be cleaned from the channel.


After installation, it should check the precision according to the certificate.

On the way of transport, jounce and vibration maybe affect precision.

It needs to adjust the precision of the press.

The punch press can be used until precision is OK.

Before starting the press, it should notice to clean the greasy filth, especially the surface of gibs and friction during the course of unpacking, then choose proper operation rule according to working requirements and make the necessary preparation of tools.

After installation of the die, use inch stroke and move the slide to the bottom dead center step by step.

Special Notice:

Don’t make die meet each other, and adjust the height of die manually.

After adjusting the die, it cannot start single and continuous stroke.

It should adjust the position of the knockout bar to make parts knockout after slide stroke stopped (near top dead center).

But when the slide moves to top dead center and the knockout bar is pushed to the bottom, it must be noticed don’t make touch the bottom of knockout bar groove for disturbing movement.

After adjustment, it adopts inch stroke and finish the stroke once step by step.

The single and continuous stroke can be done after assuring there is nothing to prevent the press working.

The air pressure of the punch press should be 0.55-0.60MPa, and the maximal pressure of the safety valve should be 1MPa.

IX. Operation Preparation

Running Preparation

(1) Push the air switch of the main control box to ON and assure the punch press machine is OK.

(2) Close the door of the main control box.

Alert: For safety, it is forbidden to open the door of the main control box when operating the press.

Operation Preparation

(1) Push the switch on the operation panel to ON, then the power indicator (AC110V loop) will light.

(2) Assure whether “Emergency Stop” button is released.

(3) When the pressure is not normal, the indicator will go out and the punch press machine will be on the status of Emergency Stop.

Now adjust the air pressure to the proper value. Operate the press until the indicator lights.

Start and Stop the main motor

  • Press the start button, the main motor will run and the main motor indicator will light.

Notice: the main motor will run if the mode switch in “OFF” position.

  • Press the motor stop button, and the main motor will stop running, and the indicator will go out. But the main motor will auto-stop if the followings appear.
  1. The fuse of the loop in the main motor blows out.
  2. The thermal relay is in the status of protection.

X. Daily Checkup

Initial Checkup

  • Clean the bolster and do not place anything on the bolster
  • Drive the flywheel with barring rod
  • Power cable specifications must be according to requirements.

Check after opening air valve

  • The air pressure of clutch should be at a specified value in the range of 0.55-0.6MPa
  • Air leak is forbidden
  • Air leak in the clutch cylinder and rotator joint is forbidden.

Check after power on

  • Press the switch to ON, and indicators of power and pressure will light.
  • Turn the mode selection switch to “inch stroke” position. Press and release “two-hand” operation button, check solenoid valve action and assure air releasing, clutch in flexible motion without interference.

Check after starting the main motor

  • Press the start button, the main motor will run and the indicator will light.
  • Check the rotation direction of the flywheel which must be the same as marked in the press.
  • Check the start and speed acceleration of the flywheel.
  • The sliding voice of the V belt slip must be normal.

Running Check

  • Check whether the performance of the press is good in Inch Stoke. Keep the two-hand operation button depressed. The punch press can not run continuously with noise and abnormal heaviness
  • The motion should be normal in Single and Continuous Stroke. In Continuous Stroke, press the emergency stop button to assure the clutch separate and the emergency stop button could be locked.
  • In Single Stroke, the press cannot run continuously when pressing the operation button.
  • In Single Stroke, the stopping position should be between +5°and -10°of top dead center. The deviation is forbidden.
  • In Continuous Stroke, press the stop button, the stopping position should be between +5°and -10°of top dead center. The deviation is forbidden.
  • In Continuous Stroke, press the emergency stop button, and the punch press should stop immediately.

Check when adjusting the slide

  • Turn the slide adjustment switch to ON, the operation will be forbidden.
  • Adjust the height of die, when the slide moves to upper and lower limit, motor adjusting must be stopped.
  • Check whether the die height indicator is same as real value.

XI. Maintenance and Safety

Operate strictly according to manual and safety procedures.

  • It should joint the clutch after the motor starts then runs at full speed.
  • Maintain good equipment earth connection and often check it.
  • When the operator leaves the press, cut off the power.
  • The working load of the press should be in the range of the safe graph.
  • Don’t run the punch press when the safety device is disassembled.
  • It’s absolutely forbidden to punch two pieces of sheet.
  • If the slide falls freely or strikes irregularly with noise, stop the punch press immediately and check it.
  • Often check air pipeline. If find air leaks out, repair it before operating the punch press machine.
  • In order to guarantee of personal safety, it is forbidden to put any part of the body enters into the dangerous area of the die. It also forbids working and maintaining in dangerous area before adopting safety measures.
  • Photoelectric protector is optional. The press has Photoelectric protector connection points.

XII. Troubles and Remedies

Troubles Reason Solution
Operation Preparation The punch press doesn’t run. 1. Air pressure is too low. 1. Check gauge pressure and adjust pressure
2. The power and main motor failures 2. Replace fuse or breaker
3. Replacement contact of Emergency Stop 3.Check Emergency Stop button
4. Poor contact of the Run button 4. Replace button
5. The circuit is cut off 5. Check circuit
6. Slide doesn’t move back to normal position emergency stop 6. Operate with inch stroke and adjust the position of slide.
In the course of operation The press doesn’t run 1. Error in solenoid valve 1. Check the solenoid valve or replace the loop of the solenoid valve.
2. The loop doesn’t connect
3. The solenoid valve turns off
The main bushing hot 1. Shaft sticks with bushing 1. re-mill shaft or scrap bush
2. poor lubrication 2. Check lubrication and clean oil way
The gib is heating 1. The clearance of gib is too small 1. Adjust the clearance of gib
2. Poor lubrication of gib 2. Check the lubrication and clean the oil way
3. Slide sticks with gib 3. Scrap gib or slide
Noise in the slide 1. Ball shape cover board loose 1. tighten the bolts.
2.The clearance of ball head is too large. 2. Adjust the thickness of spacer
Continuous stroke when press inch stroke button 1. Run button fault 1. Replace button
The punch press cannot be reset when pressing Emergency Button 1. Poor replacement of button 1. Replace button
The clutch doesn’t work when pressing two-hand buttons simultaneously. 1. Air pressure is low 1.Check air source or adjusts regulator.
2. friction block wear off 2.Adjust clearance or replace new friction
3. Failures of electric cable 3.Check the circuit and eliminate troubles
Press single stroke, the punch press doesn’t stop at the top dead center. 1. Air pressure is low. 1.Check air source and adjust it
2. Wrong position of the proximity switch. 2. Adjust the cam switch.

XIII. Easy Wearing Parts List

No. Position Wearing Parts Specification Quantity Remark
1 Frame Back Main Bush 1 Figure10
2 Driving Parts Front Main Bush 1 Figure 9
Bearing GB/T297-1994 132316 (80x 170×61.5) 1
Bearing GB/T297-1994 33220 (100x180x63) 1
Bearing GB/T276-1994 6032 (160x240x38) 2
 O Type Seal Ring GB1235-76 240X5.7 1
230×5.7 1
155X3.1 2
170×3.5 1
85×3.1 2
95×3.1 1
Seal Ring for rotation GB9877.1-88 190X220X15 1
Lip Seal Ring SN70 SN70/TC10012512 2 Import
V belt GB1171-74 B-2700 3
3 Slide Connecting rod bottom bearing 1 Figure 11
Connecting rod upper bearing 1 Figure 12
 O Type Seal Ring GB1235-76 130×3.1 1
35X3.1 1
20×2.4 2
75×3.1 1
220×5.7 1
Y Type Seal Ring for Shaft d110 1
Beating GB/T292-1994 46206 (30x62x16) 2
Right Angle combined seal for the hole of Piston TB1-IIA 180><7.00 1
Lip Seal Ring GB9877.1-88 PD30x50x7 2

XIV. Attached Figures

Figure 1 Product Structure
Figure 2 Frame
Figure 3 Driving Parts
Figure 4 CIutch and Brake
Figure 5 SIide
Figure 6 Pneumatic schematic diagram
Figure 7 Lubrication schematic diagram
Figure 8 Foundation plan
Figure 9 Front Main Shaft Bushing
Figure 10 Back Main Shaft Bushing
Figure 11 Connection bottom bushing
Figure 12 Connection upper bushing

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