![]() ![]() Delaying the starting of the drafting rollers by a few seconds would solve this problem. The acceleration of the spindle lags behind that of the drafting rollers and the yarn slackens if it slackens too much, this might lead to balloon instability and the end breaks. Additional slackness present on the spindle belt compounds the problem. When the ring-spinning machine is started, the belt tension in the forward direction increases, and at the back it decreases enough to build up the required torque on the spindle. The initial belt tensions on both sides of the spindle are the same while the machine is at rest. The drive for the drafting rollers is a rigid one (by gears) and the spindle is driven by a flexible drive (belt). Rengasamy, in Advances in Yarn Spinning Technology, 2010 7.4.2 Delayed start-up of drafting rollers The effects of dust can be slowed down greatly and possibly eliminated by installing larger pulleys and larger reverse idler pulleys. Often, adequate shielding between the heat source and belts can be provided.ĭust Dust can be very detrimental to belts and is often responsible for bottom cracks. ![]() Therefore, the use of standard V-belts above this temperature should be avoided. However, at temperatures above 140☏, over-curing will occur and belt life will be shortened. If standard belts are operated below 140☏, their materials of construction are not affected. Nevertheless, there is no need to replace belts simply because bottom cracking has been detected.Įxtreme heat In the manufacturing process, belts are cured with scientifically controlled heat for given periods of time. Cracking on the bottom sections of belts does not cause a loss of strength or operating efficiency, but can lead to eventual failure. Types of belt damage to watch for are cracking, which can be caused by excessive heat and dust stretching added load damage and damage as a result of belt whipping.Ĭracking Cracking can be caused by exposure to high temperature and/or dust. If oily conditions cannot be avoided, special oil-resistant belts should be used. It is important to avoid over-applying lubricants to bearings, but note that under-application can contribute to early failure with resulting damage to belts due to friction build-up and drag. Dirt accelerates belt wear and belt traction is impaired when dirt is allowed to build up.ĭo not expose belt drives to oil or grease under any circumstances! Potential sources of oil and grease include leaking bearings, which should be repaired immediately. Ĭommon sources of belt contamination are dirt, oil, and grease, all of which should be removed from belts and pulleys.The following are some of the reasons for belt squeaking, which is often described as sounding like a bird chirping: ![]()
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