With the rapid development of optical communications, the amount of optical fiber loose tube cable for outdoor has increased rapidly. However, the capacity of the optical fiber in the loose tube is limited and it is impossible to make the loose tube large. In addition, in order to facilitate the connection identification of optical fibers and the distribution of optical nodes, the number of optical fibers in every loose tube should not be too large. For large-capacity communication requirements, the loose tube can only be twisted into cables according to certain rule.
The stranding of optical fiber cable can increase the number of optical fiber cores to meet the requirements of large-capacity communication. After the loose tube is twisted at a certain pitch, its cable core structure will become very stable, which is helpful for future construction. Because the loose tube is twisted according to a certain spiral angle, the soft performance of the cable is improved. Due to the stranding, the loose tube has a certain stranding radius, which increases the excess length of the optical fiber compared to the optical fiber and improves the environmental resistance of the optical cable.
At present, there are SZ stranding method and one-way (S or Z) stranding method for fiber optic cable. Because SZ stranding has the effect of canceling the stress of cable formation, SZ stranding is mainly used at present.
The so-called SZ stranding is when the stranding element reaches the specified S direction (or Z direction) number of twisted revolutions along the longitudinal axis of the optical fiber cable, and then reverse direction to stranding the same S direction ( Or Z direction) twisting numbers along the Z direction (or S direction). After the same number of turns of twisting, the twisting form of another twisting cycle is restarted. The quality of the SZ stranding process directly affects the performance of the finished optical fiber cable.
The realization of the SZ stranding process is completed by the SZ stranding line. Our company has many years of experience in the research and development of optical fiber cable production equipment. The SZ stranding line can be used for stranding (1～12) core optical fiber loose tube with fast production speed, high production efficiency, stable stranding pitch and other characteristics.
The main technical parameters of the equipment are as follows:
Loose tube diameter/Number of tube
Structure speed (m/min)
Production speed (m/min)
(Binding pitch=25mm, stranding pitch=65mm)
Binding pitch (mm)
Stranding pitch (mm)
SZ stranding angle
SZ stranding head speed (rpm)
Binding head speed (rpm)
This production line is mainly composed of pay-off for optical fiber cable reinforcement, pay-off tension control device, pay-off device for loose tube/filling rope, pay-off device for water blocking yarn , SZ oscillator device, dual concentric binder, jelly filling device, longitudinal tape pay-off device, single head binder device, capstan, take-up tension control device, take-up device and electrical control system, etc.
The loose tube / filling rope pay-off device can release multiple loose tubes or filling ropes.
The pay-off and lifting of the reel are driven by the AC geared motor, controlled by the inverter, which can ensure that the pay-off speed is synchronized with the capstan speed. The clamping of the wire reel is realized by the cylinder. The pay-off tension can be adjusted by changing the balance position of the swing arm. The pay-off tension can meet the technological requirements of different tube pay-offs.
This device is composed of multiple stranding plates , which are driven and rotated by multiple AC servo motors to realize SZ stranding of the optical fiber loose tube.
The stranding angle can be set and displayed on the touch screen. The whole device has eighteen-level drive set. This ensures that the stranding body has a smaller rotational inertia and a faster steering speed. This also ensures that the SZ change direction point is smoother, no straight groove, faster speed.
The device is equipped with a stainless steel safety shield, and the opening angle is greater than 90°, which makes it convenient for wiring or adjusting the core, and safe and reliable operation environment.
The device is equipped with an emergency stop switch. Pressing the emergency stop button in an emergency state can stop the production equipment in a timely manner to ensure personal safety and reduce the waste products.
The function of the device is to bind the cable core with polyester yarn at the reversal point after stranding to avoid loosening the cable core. The device adopts the double-head concentric pot type yarn binding form, which can ensure the uniformity of the SZ stranding pitch.
The rotation and tension of the yarn are controlled by the AC servo motor, which can run reliably at high speed. The tension can be set on the touch screen and adjusted online. And the tension of the yarn is automatically adjusted with the change of the diameter of the yarn, so as to ensure the constant tension of the yarn. At the same time, the device also has the function of yarn brake alarm and emergency stop.
This device is also equipped with anti-twisting device. The anti-twisting device adopts caterpillar type structure to ensure that the angle of the loose tube will not lost and the stability of the cable core is ensured after the stranding of optical cable.
1. PLC adopts Siemens brand.
2. The main low-voltage electrical appliances adopt Siemens brand.
3. The AC motor adopts Siemens brand.
4. The AC motor controller adopts Danfoss brand.
5. AC servo motor adopts Panasonic brand.
6. The bearings adopt NSK brand.
The installation and commissioning of SZ stranding is divided into three steps: the installation of mechanical parts, the installation of electrical part and commissioning of the equipment
This production line should be installed in flat ground, smooth channel and bright light workshop.Installation standard. “SZ” stranding table center line, it is also the center line of full production line.
First, use the ink line to set the center line of whole machine on the floor to determine SZ Stranding table position according to outline dimensional drawing of SZ Stranding line.
Check the plane of stranding table installation floor, there must be no obvious rugged situation.
Then, pull a fine wire of 0.5mm above the machine as the standard of alignment.
Installed SZ stranding table on a correct position
On right hand side, water proof yarn pay-off, high and low guide device for loose tube pay-off ( 2 sets each for high and low), CSM pay-off ( 2set), loose tube pay-off (6 sets), steel wire holder, Φ800 wheel tension, PN1250 swing beam pay-off are installed. On left hand side, dual concentric binder, water proof tape pay-off, single binder, Φ800 dual wheel capstan, Φ800 dual wheel tension, PN1250 swing beam take-up with traversing device are installed. And adjust in correct position for each part.
At last install electric control system and adjust the position of each parts, including the position of center height, left and right, forward and back. Special attention: adjust the center line of double head common point binding yarn device, after rotate and check normal then fixed base.
According to the gas drawing to connect gas
Installation dimensions see SZ stranding line layout drawing. Finally, the parts are fixed by expansion bolts (nut).
When electric control cabinet in its place then start pay-off, connect the electric circuit of each equipment according to electrical schematic diagram and wiring diagram requirements of SZ stranding line.
All equipment must be connected to the earth reliably to ensure safety.
Make sure the voltage into the control cabinet is normal
According to electrical requirements and standard wiring
Due to the different requirements of the cable structure and the cable process, the machine must be adjusted before producing.
The adjustment of CSM pay-off tension. Active pay-off, adjust the thrust cylinder pressure size of accumulating tension controller which can change the size of pay-off tension, until reach process requirements.
The adjustment of loose tube tension. The tension is given by the pendulum system on the loose tube pay-off frame, adjust the position and number of balance weight then can change the tension size.
Adjustment of SZ Stranding pitch, back-angle, the setting and reverse angle of over limit and over-twisting protection are adjusted and set in the IPC.
The adjustment of dual binding yarn tension and pitch are adjusted ad set in PC.
The adjustment of water proof tape tension: By adjusting the tension of the permanent magnet damper to adjust the tension of the pay-off tape
The adjustment of single binding yarn tension and pitch are adjusted ad set in PC.
The adjustment of take-up tension: Adjust the compressed air pressure of accumulating type take-up tension controller then adjust tension size.
The adjustment of traverse position: Through the touch screen of take-up electric control cabinet operation panel to set. Quickly change the position of cable tray and centering device, press the right and left fast traverse button on the operation button box of take-up stand with traverse.
The adjustment of traverse pitch: According to the different diameter of the cable core, through the operation panel on the touch screen given a certain pitch value, then can achieve the cable pitch settings and adjustments.
Q: Can I visit your factory?
A: All the customers from both home and abroad are warmly welcomed to visit our company and factory.
Q: Do you supply the installation and commissioning?
A: Yes, we do as followings:
-As soon as customer informed us the machines are put in the right place, we will send both mechanical and electrical engineer for machine start up.
-No-load testing: After machine installed completely, we make no-load testing first.
-With-load testing: Usually we will can produce 3 different wires to make load testing.
-Acceptance report: After the buyer confirms that machine can reach all specification under contract, the acceptance report will be signed for our record that machine will be in guarantee period.
Q: What information should I offer to get a detailed quotation from you?
A: For single machine: Usually we need to know inlet wire size, outlet wire size to be produced, productivity, pay off and take up size to choose the right machine.
For new cable plant or new cable production line, we need to know the datasheet of cables to be produced, the productivity, the standards to be followed, etc to design all machines needed.
Q: Can you supply the auxiliary equipment along with the machines?
A: Yes, definitely.
We has supplied heat exchanger, copper/aluminum powder filter machine, cooling tower, chiller, air compressor, drawing dies, pointing machine, cold welders, bobbins etc. with our machines.
Q: Could you do the design for the whole plant?
A: Yes, this is our advantage.
With the data sheet of cable to be produced, the standard your cables should follows, the productivity you expected. Our engineer on production technology and machinery will make design of production machines, test equipment, accessories like bobbins, dies, rewinding lines and materials needed.
Q: How can I know the status of my order?
A: We have our OA system on tracking the production.
For any of your request we can send photos and videos of your order, also we can use FACETIME to let you know the production.
Q: How do you work on the inspection before delivery?
A: We will make dynamic balance testing, levelness testing, noise testing, etc. during production.
After production finished, usually we make no-load running of each machine before delivery. Customers are welcomed to attend the inspection.
Q: What exhibitions will you attend, can we meet in the fair?
A: Dusseldorf International Wire and Cable Fair;
Wire South America Fair;
International Wire and Cable Fair in Shanghai;
International Istanbul Wire Fair, etc.
wire Southeast Asia Fair, etc.