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Sheet Metal Machinery FAQ

Shearing Machine
1. It there any restriction for the target plate?
Our shearing machine is applicable for almost all kinds of metal sheets, except for ones that are harder than our shearing blades, such as alloy saw blade, high-speed steel, etc.

2. What should the user pay attention to when operating this sheet metal shear?
a. Before working, please carefully check all the mechanical parts, electrical devices as well as lubrication system, and remove irrelevant tools, gauges and tailings near the working table.
b. It is not proper to manipulate the shearing machine with only one person. Instead, 2 or 3 people should work together for material feeding, machining precision control and material discharge. In addition, one person should be in charge of the whole process.
c. The blade gap should be adjusted according to the plate thickness, and it is not allowed to shear plates in different materials or specifications, while overlap shearing is also forbidden. Moreover, the surface of unprocessed metal plate should be flat, and the plates that are too narrow to be clamped are not suitable for this machine.
d. The belt, flywheel, gear, shaft and other moving parts must be equipped with protective covers.
e. When feeding metal plate, the operator's fingers should be 200mm far from the blade at the least, and be away from the work holding device. Meanwhile, the protective fence equipped to the shearing machine must be scientifically fixed to prevent blocking of operator's eyes. Thus, the operator will get a clear view of the machining part. The scrap materials generated during this process are sharp and dangerous for people, so please handle them in time.

3. What if the hydraulic shearing machine doesn't return?
a. First, please check the oil tank, and add oil if the oil level is too low.
b. If the previous one doesn't work out, go and detect the condition of solenoid valve that is responsible for the upward movement. If electricity is not detected, it means that there is a problem with the control loop.
c. If electricity is detected, maybe the solenoid valve is broken. Please fix it or replace it with a new one under this condition.

4. How to add nitrogen gas?
Get a bottle of nitrogen gas and connect it to the inlet of nitrogen gas cylinder with the help of a pipe which is supplied by us. Open their valves, keep an eye on the pressure gauge on the shearing machine, and close these valves after the pressure reaches to the desired value as indicated on the instruction book.

5. What about the machining precision?
The machining process is manually controlled, so the precision changes with operator's skill. However, the CNC shearing machine has an ensured processing accuracy.

Press Brake
The slide moves down normally, but it can't return back. What is the reason?
This problem is divided into several conditions.
1. There is no return force, and this may be caused by the electric circuit or blocked pressure regulating valve.

2. There is return force, but it is too small. Under this condition, please increase the force. However, if the change-over valve is blocked, this phenomenon may also occur.

3. The return force is big enough, but the slide still moves up slowly. There are four possible reasons for this.
a. The hydraulic valve is blocked.
b. The oil way pressure for return loop is too low.
c. The change-over valve is stuck, or its change over function fails.
d. The spool of solenoid valve is inversely installed.

4. The slide moves up and down normally, but during pressing process, the working pressure can't be added or it takes too much time.
a. There is a problem with the electric circuit, and the solenoid valve is not electrified.
b. The valve spring or valve spool for return loop is damaged.
c. Screws of suspension cylinder fall off.

5. The lathe slides down due to electric problem, damaged seal ring of oil cylinder, or failure of oil way for locking device.

6. The lathe moves down slowly or it shakes.
a. The oil cylinder is broken, or the screw and nut in the oil cylinder are stuck.
b. The guide rail is not vertical, or it is damaged because of abrasion. Also, it may be lead by damaged valves.

Plate Bending Machine
1. During working, the main motor stops running.

Reason: The motor is overloaded, or the machine is bending straight edge of metal plate.
Solution: Cut down the reduction of upper roll, and please use this machine to bend straight edge.

2. The bearing is overheated.
Reason: The bearing is installed in a wrong or unmatched way, or the axle journal and hole are damaged due to abrasion.
Solution: Set the bearing in a correct way, and make sure if lubrication oil is needed. If necessary, replace the damaged components.

3. Safety pin in the safety coupling is cut off.
Reason: Overload problem.
Solution: Lower the reduction of upper roll. If the safety pin is broken, please change a new one.

Jiangsu Jiuwei Heavy Industry Machine Co., Ltd.

Add.: No.68 Shuanglou Road, Qutang Industrial Zone, Haian County, Jiangsu Province, P.R.C

Tel.: +86-513-80680882
(Foreign Trade Department)