“How to shorten the doffing downtime and reduce the doffing end-break rate is the key to making good use of the spun yarn long lathe. By reasonably adjusting the doffing process parameters and correctly executing the doffing operation procedures, we have achieved a higher doffing end retention The rate.”
In order to ensure the yarn retention rate, the F1520 spinning car has a function to solve the “little braids” in the doffing action program. Before the main machine starts, the ring plate rises to the middle yarn position (the middle position of the bobbin, the specific position can be set). When the main machine starts, the ring plate drops quickly to untie the braid. The company’s leading varieties of pure cotton 18.5 tex and 14.8 tex yarns have less doffing ends, so the doffing end retention rate is high, reaching an average of more than 98%.
We mainly take the following measures to improve the doffing end retention rate:
Select appropriate travellers, Adjust the spacing of the wire ring cleaner to prevent or reduce the hanging of the wire ring. Adjust the number of turns of the waste wire coil to prevent too much wire return from hindering the normal movement of the wire ring and preventing “little braids” from deteriorating and causing breakage. The number of turns of the waste silk disc can be adjusted through the following parameters: spindle off – spindle braking time (3 seconds); ring plate lowering – spindle off time (0~0.5 seconds); doffing spindle speed (5500~6500 rpm ); the descending speed of the doffing ring plate; when the combined adjustment of the above 4 items cannot achieve the ideal number of yarn return turns, check and adjust whether the electromagnetic brake system is in good condition. The waste silk reel should be cleaned once a week. When spinning varieties with thicker yarn count, the number of cleaning times can be increased according to the waste silk situation.
Set the appropriate middle yarn position and starting spindle speed to ensure that the balloon does not touch the spinning bobbin end, the yarn separation board, and the distance between the leaf plate and the spinning bobbin. Keep it appropriate. The doffing time of the automatic doffing system is about 260 seconds, and the yarn retention rate is higher than that of manual or manual first and then automatic, so the automatic doffing system should be selected instead of manual. The doffing worker should check the situation of the spindle winding wire when doffing. If any spindle wire winding is found, it should be cleaned in time to prevent the spindle wire winding from hindering the movement of the traveler and causing “little braids” and end breakage.
Check whether the blower and suction fan are working well every day. This prevents yarn defects and embossing on the convex disc due to poor function of the blower and suction fan, causing the convex disc to be unable to be pushed or dislocated, affecting the tube grasping and normal doffing. Special personnel are assigned to clean the spun yarn car belly once per shift to prevent spun yarn breakage caused by floating flowers on the car belly. The pipe grabber, bobbin and machine parts should be picked up in time when they fall to the ground to prevent the air frame from being pushed up by the rocker arm and causing misalignment of the air frame and affecting the doffing. The convex disc track is cleaned once every 15 days with the wiper to prevent accumulation of flowers on the convex disc track, causing dislocation of the convex disc and affecting doffing. The doffing air frame is inspected and leveled once every 15 days as the machine is wiped, to prevent the air frame from being out of position and affecting normal doffing. The photoelectricity of each part should be inspected and cleaned in time to prevent photoelectric failure from affecting the normal doffing. Spun yarn bobbins must be sorted regularly to eliminate unqualified bobbins.
Automatic, manual
The F1520 long spinning doffing machine has two forms: automatic and manual. When using a long car for the first time, for safety reasons, the equipment manufacturer will recommend using the manual first and then the automatic method. That is, during normal production, the doffing knob is in the manual position. After the doffing alarm light flashes, the doffing worker goes over to inspect the car. If there is any abnormality, turn the doffing knob to the automatic position and start the automatic operation program. The advantage of this is that it can prevent accidents caused by negligence of equipment and personnel. The disadvantage is that if the doffing knob is turned on the manual, the servo motor will always be powered on, which will seriously shorten the life of the servo motor.
Long cars use aluminum sleeve spindles and are equipped with brakes. The aluminum sleeve spindle is equipped with a thin-arm spun tube. The tight fit between the spun tube and the spindle is mainly achieved through the three elastic shells (also called “cat eyes”) on the upper part of the spindle. When the spindle is running, centrifugal force will cause the “cat’s eye” to press against the inner wall of the spun yarn tube to achieve a tight fit between the tube and the spindle. Some spinners are not used to using brakes, while others find it slow to splice using brakes, and may pull yarn splices directly without using brakes. This will cause the cat eye of the spindle to fall off and the inner arm of the bobbin to be damaged, which will not only damage the bobbin but also affect the yarn quality, which is very harmful. Therefore, we must prevent this situation from happening. In addition, if the brake is applied to the spindle for a long time, it will cause the spindle to become hot, the brake to burn out, the spindle belt to burn out, and even the spindle to burn out, so this kind of bad operation must be prevented. We should also try to avoid adjacent machines from doffing at the same time to ensure safety.
When changing varieties, the drafting gears need to be modified at the front and rear of the car. Be sure to check carefully, otherwise errors will occur. branch. When sampling raw yarn, the front and rear of the car should be taken to prevent mistakes. When the F1520 automatic spinning doffing system is doffing, the fenders are automatically turned up. It is necessary to prevent the wiper plates from remaining on the fenders when the fenders are turned up, causing damage to the machine parts. The F1520 spinning car is equipped with an electronic lifting system and is electrically complex and has many servo motors. Therefore, the power distribution system must have a harmonic processing device when loading the equipment to prevent harmonic interference from causing unstable equipment operation and poor bobbin formation. When wiring the spun yarn car, the power lines and data signal lines must be separated to prevent equipment malfunction caused by interference in the data signal lines. </p
