Adhesive sealing technology is an effective technology and method to replace the traditional mechanical locking, holding, sealing and connection by chemical means. That is, adhesives are used to replace traditional spring washers, cotter pins, slotted nuts and various gaskets, gap fit is used instead of transition interference fit, and bonding method is used instead of riveting. In the manufacturing and assembly of press parts, adhesives and their application technology can play a shock-proof, anti-loose, anti-corrosion and leak-proof effect, which can reduce machining installation procedures, save time, and improve product quality and production efficiency.

2 Application of anaerobic glue in large press manufacturing

2.1 Anaerobic cylindrical parts are fixed

     Most of the large machinery is under heavy load, vibration load conditions of continuous work, therefore, often appear bearing outer ring and bearing seat, inner ring and shaft, pulley and shaft or shaft sleeve and hole between the movement or rolling key and other mechanical failures. When the matching gap is within the range of 0.38mm, Fengshen 600 series of adhesive can be used instead of brush plating, transition and interference to ensure the normal use of the equipment. The performance of this series of adhesive is shown in Table 1.

              Table 1 600 series adhesive properties and applications ^*

* The initial solidification time is 10-20 min, the curing takes 24 h, and the working temperature is -54 ~ 149 ℃.

2.1.1 Bonding of rolling bearings with matching parts

Ls4-2000 T closed four-point multi-link press, the large flywheel radial runout is abnormal during assembly trial run, causing the whole machine to shake. The inspection found that there was a 0.05mm clearance between the inner ring of the bearing and the diameter of the high-speed shaft. If the shaft diameter is sprayed, the cost is about 2000 yuan and the cycle is long. The use of 680 glue can solve the problem with only a few tens of yuan, and the press has not been found abnormal in the user's use after repair. In the trial production of J 39-900 T closed four-point crank press, it was found that the accuracy was unstable and the temperature rise at the middle transmission journal exceeded the standard during assembly, and the clearance between the bearing outer ring and the bearing seat hole of the beam was found to be 0.15 mm. If the hole is reamed and inserted, the process is complicated and the cost is high. After applying 680 on the bearing seat hole, the accuracy of the whole machine is stable, and the heat of the journal is eliminated.

2.1.2 Used for bonding the outer diameter of the plain bearing with the housing

J 31-1250, J31-1000 closed single point press, the crankshaft connecting rod bearing is a large two-half plain bearing, easy to produce deformation during processing and installation. We first glued the two half bearings to the shell with 1609 adhesive, then drilled, tapped, and fastened with screws, and achieved good results.

2.2 Application of anaerobic adhesive in the locking of threaded connection

It is common for mechanical equipment to stop due to loose thread connection. For this reason, the thread cementing agent is used instead of the traditional anti-loose spring washer, which can make the thread mesh reach 100% contact. This tight method can not only obtain reliable locking effect, but also prevent leakage of thread part. The commonly used adhesives in actual production can be roughly divided into two kinds, one is the detachable thread locking adhesive (such as 1242, 1262), and the other is non-detachable (such as 1271, 1277)

 Table 2 Properties and applications of 200 series thread locking adhesives

 * The fixed time of anaerobic adhesive in curing is 20 min, the full curing takes 24 h, and the working temperature is -54 ~ 149 ℃.

2.2 Application of anaerobic adhesive in thread sealing and plane sealing

     In hydraulic and pneumatic systems of heavy machinery, threaded connections of pipes and various joints are often sealed with solid materials (such as PTFE tape, etc.). These sealing materials are prone to aging and failure under the action of media, pressure, temperature, and external forces, resulting in oil leakage or pneumatic pressure drop and other failures. The 1545 pipe thread sealant is applied on the connection thread, and then the fastening force is applied according to the requirements of the assembly process, and the remarkable sealing effect is obtained. On the large diameter high-pressure air pail such as press balancer and air cushion, the flange connecting plane is usually sealed by paper gasket. When running, the paper pad is very susceptible to water swelling, corrosion, and under the action of external forces (such as vibration) to produce air leakage, so that the press can not work normally. For this situation, the 1515 sealant with good elasticity is selected and can replace the gasket, which not only solves the problem of air leakage of the flange, but also improves the quality of the product.