How are high-quality brewery beer equipment processed?
Welding deformation and preventive measures in the processing of stainless steel tanks
Wrong welding in the processing of beer equipment will cause deformation of the stainless steel tank, major changes in the surface material, and the internal surface that does not meet the requirements of the brewing process, which will seriously cause the tank to leak and reduce the service life.
1. Methods to prevent and reduce welding distortion during brewery equipment processing The method of preventing and reducing welding deformation during making the brewery equipment tanks must consider the welding process design and overcome the changes of the cold and heat cycles during welding. The shrinkage cannot be eliminated, but it can be controlled. There are several ways to reduce shrinkage deformation to get perfect quality brewery tanks, including mash tun, lauter tun, boiling kettle, whirlpool tun, fermenter tank, bright beer tank, glycol water tank, cold water tank, hot water tank etc. Tiantai help you set up your own brewery at high quality and reasonable price.
1 Do not over solder
The more metal filled in the welding point will produce a greater deformation force. Correctly setting the weld size can not only get smaller welding distortion, but also save welding materials and time. The amount of weld metal for filling welds should be minimal, and the weld should be flat or slightly convex. Excessive weld metal [brewery equipment] will not increase the strength. On the contrary, it will increase the shrinkage force and increase the welding deformation.
2 Intermittent weld
Another way to reduce the amount of weld fill is to use more discontinuous welding. Such as welding reinforcement plates, intermittent welding can reduce the fill of the weld by 75%, while also ensuring the required strength.
3 Reduce the weld bead
Welding with thick welding wire and fewer beads has less deformation than welding with thin welding wires and multiple beads. [brewery equipment for sale] When there are multiple passes, the shrinkage caused by each pass increases the total shrinkage of the weld. It can be seen from the figure that the welding process with less bead and thick electrode is better than the process with multiple bead and thin electrode.
Note: Use thick wire, less bead welding or thin wire, multi-bead welding process depends on the material, general low carbon steel, 16Mn and other materials are suitable for thick wire, less bead welding, stainless steel, high carbon steel and other materials are suitable for fine Welding wire, multi-bead welding
4 Anti-deformation technology
Before welding, make the parts bend or tilt in the opposite direction of welding deformation (except overhead welding or vertical welding). The preset amount of anti-deformation needs to be determined through experiments. Pre-bending, pre-setting or pre-arch welding parts are a simple way to use reverse mechanical force to offset welding stress. When the workpiece is preset, the deformation of the workpiece and the welding seam shrinkage stress is opposite. The preset deformation before welding and the deformation after welding cancel each other out, so that the welding workpiece becomes an ideal plane.
Another commonly used method to balance the shrinkage force is to place the same welding workpieces opposite each other and clamp them. Pre-bending can also use this method. Before clamping, place the wedge in the proper position of the workpiece.
Special heavy welding workpieces can produce the required balance force due to their rigidity or the mutual position of the parts. If these balance forces are not generated, other methods must be used to balance the shrinkage force of the welding material to achieve the purpose of mutual cancellation. The balance force can be other contraction forces, the use of tooling and fixtures to form a mechanical restraint force, the restraint force formed by the order of assembly and welding of components, and the restraint force formed by gravity.
5 welding sequence
Determine the reasonable assembly sequence according to the structure of the workpiece, and make the structure of the workpiece shrink in the same position. Open double-sided grooves in the workpiece and the shaft, adopt multi-layer welding, and determine the double-sided welding sequence. Intermittent welding is used in fillet welds, and the shrinkage in the first weld is balanced by the shrinkage in the second weld. The fixture can fix the workpiece at the required position, increase the rigidity, and reduce the welding deformation. This method is widely used for welding small workpieces or small components. How to start a brewery? Due to the increased welding stress, it is only suitable for low-carbon steel structures with better plasticity.
6 Remove shrinkage after welding
Percussion is a method of counteracting the shrinkage force of the weld, as the weld is cooling. Knocking will extend the weld seam and become thinner, thereby eliminating stress (elastic deformation). However, when using this method, it must be noted that the root of the weld cannot be knocked, and cracks may occur during knocking. Generally, knocking cannot be used on the cover weld bead.
Because, the cover layer may have weld cracks, which will affect the weld inspection and produce a hardening effect. Therefore, the use of technology is limited, and there are even examples that require only tapping in the multi-layer weld bead (except for bottom welding and cover welding) in the bead strike to solve the problem of deformation or cracks. Heat treatment is also one of the methods to remove the contraction force, controlling the high temperature and cooling of the workpiece; sometimes the same workpiece is clamped and welded back to back, and the stress is eliminated by this alignment condition and the residual stress of the workpiece is minimized.
7 Reduce welding time
Heat and cooling are generated during welding, and it takes time to transfer heat. Therefore, the time factor also affects the deformation. Generally, it is desirable that the welding is completed as soon as possible before the bulky workpiece is heated and expanded. The welding process, such as the type and size of welding rod, welding current, welding speed, etc. affect the degree of shrinkage and deformation of the welding workpiece. The use of mechanized welding equipment reduces the welding time and the amount of deformation caused by heat.
2. Other methods to reduce welding distortion 1 water block
Many techniques can be used to control the welding deformation of special welding workpieces. For example, in thin plate welding, the use of water-cooled blocks can take away the heat of the welding workpiece. The copper pipe is welded to the copper fixture by brazing or soldering, and the water pipe is used for circulating cooling to reduce welding distortion.
2 Wedge block positioning plate
"Positioning plate" is an effective technique for controlling welding deformation during butt welding of steel plates, as shown in the figure. One end of the positioning plate is welded to a plate of the workpiece, and the other end is wedge-shaped into the pressing plate, and even multiple positioning plates can be arranged to maintain the positioning and fixation of the welded steel plate during welding.
3 Eliminate thermal stress
Except in special circumstances, it is not the correct method to use heating to eliminate stress. It is necessary to prevent or reduce welding deformation before the completion of the welding of the workpiece.
3. Conclusion In order to reduce the influence of welding deformation and residual stress, the following points should be paid attention to when designing and welding workpieces:
(1)Do not perform excessive welding;
(2)Control the positioning of the workpiece;
(3)Use intermittent welding as much as possible, but should meet the design requirements;
(4)Use the smallest weld foot size as much as possible;
(5)For open slope For joint welding, the amount of joint welding should be minimized, and bilateral grooves should be considered instead of single-side groove joints;
(6)Multi-layer and multi-bead welding should be used as much as possible to replace single-layer double-side alternate welding. Open the double-sided groove welding at the workpiece and the shaft, adopt multi-layer welding, and determine the double-sided welding sequence;
(7)adopt multi-layer welding with less bead;
(8)adopt low heat input welding process, which means higher Deposition rate and faster welding speed;
(9)The positioner is used to make the workpiece in the boat-shaped welding position. Boat-shaped welding position can use large diameter welding wire and high deposition rate welding process;
(10)As far as possible, set the welding seam on the neutral axis of the workpiece, and weld symmetrically;
(11)As far as possible through the welding sequence and welding positioning Make the welding heat evenly diffused;
(12) Weld to the unconstrained direction of the workpiece;
(13)Use fixtures, tooling and positioning plates for adjustment and positioning.
(14)Pre-bend the workpiece or preset weld joints in the opposite direction of contraction. (15) According to the sequence of separate welding and general welding, the welding can be kept in balance around the neutral axis.
4. Tiantai supply quality brewery equipment tanks Tiantai company produces high-quality brewerybeer equipment. All welding workers have undergone rigorous selection and training, and possess very superb welding skills. We have accumulated a wealth of experience in welding. We have accumulated detailed data for different thicknesses of stainless steel, different weld beads, different welding angles and different welding conditions to ensure the food processing and service life of the welded tank. All reached the best level.
Tiantai produces more than 3,000 sets stainless steel tanks for brewery beer equipment each year. These brewery tanks are installed in the United States, Canada, Australia, Europe, the United Kingdom, South Korea, Japan and other countries and regions. Reliable brewery beer equipment quality and rich craft brewing technology provide the most powerful support for your craft brewing business.
Request A Quote