In the construction of pipelines, the quality of welding is of paramount importance. Each weld is X-rayed – so any weld defects can take time and money to repair. Proper preparation and cleaning of the base material is the first step in ensuring high quality welding and minimizing defects in demanding piping environments.
There are many types of surface conditioning products that can be used before, during and after welding in pipeline construction. Choosing the right product helps ensure high quality welding while saving time, so welders can be more efficient under tight schedules.
Consider the various options for preparing and cleaning pipe materials and welds, as well as best practices for each solution.
Welding preparation tube
The first step is to prepare the bevel. The pipe is usually delivered to the job site along with the created groove. However, this requires the use of a grinding wheel to clean and support the ground, which is the flat portion of the beveled end. The flat region allows for a proper spacing between the two tube ends so that they can be aligned and secured together for soldering. A slotted wheel or a 1/4 inch wheel is a good job for this task.
When using the grinding wheel, do not stay in any position for too long as this will cut the material. Instead, keep the wheels moving and drive around the land while keeping the wheels as flat as possible.
Once the pad is formed, the bevel and inner diameter of the pipe opening should be cleaned for soldering. The correct tool for cleaning the bevel depends on the degree of corrosion on the pipe. The operator’s preference also plays a role. The most common way to clean the bevel is to use a wire wheel, but this depends on the condition of the pipe. Cleaning pipe
When the pipeline arrives at the site, the condition of the base material can change a lot. The pipe usually rusts – depending on the length of time since manufacture and the storage conditions of the pipe. The longer the time between the manufacture of the pipe and the preparation of the weld, the greater the chance of rust accumulation.
If the surface of the pipe is only slightly rusted, the conditioning product required will be different than the pipe with a heavier rust.
Pipe wire brushes and Wheels: Manual pipe wire brushes or wheels can often be used to remove slight surface rust. The pipe wire brush effectively removes loose material from the pipe surface without the need to replace the base metal.
Product options in this category include manual wire pipe brushes for small diameter pipes or power wire wheels (for example, threaded bead wheels), and pipe wire brushes for large diameter pipes and faster cleaning. Wire wheels can be used to clean pipe surfaces and weld welds between welds before welding. Pipe wire brushes tend to clean more surface area and usually clean faster, but they also tend to backflush if the cup hits the wrong part of the pipe. Both products are effectively cleaned. Although the choice usually depends on the operator’s preference, the most common is the wire pipe brush.
Please note that the wire product also removes the burrs that may form when the pad is created.
Because the design of the reel and brush allows the end of the thread to work, it is important to orient the tool so that only the end of the thread can strike the work surface. This promotes the most effective cleaning action and reduces the urge for the operator to push. It also helps to extend product life and reduce the risk of wire breakage. Use a pipe wire brush to apply a slight pressure – just a little more than the weight of the grinder – to get the wire tip to work.
Flap: If the surface of the substrate rusts more than this – and may even create pits in the steel – it requires a more corrosive product to clean the metal. The bevel must always be thoroughly cleaned and any rust or dents on the material removed.
In this case, the valve flap is a good choice, especially the 60-grain valve disc, which can effectively remove any rust, pits and sag on the pipeline, while also minimizing the gas generated by the grinding wheel. The possibility of planing.
There are many different material types for the flaps. The disc with aluminum backing is more sturdy and is ideal for maintaining beveled edges without rounding the material. Rounding the beveled edge during the cleaning process may be detrimental to proper filling of the weld.
Pass cleaning
After the root bead, it is necessary to sand the weld to ensure that the next pass or hot track is properly penetrated. This can be done using a 1/8 inch grinding wheel along the root bead, which helps to form a flat or U-shape at the bottom of the weld.
When placing a subsequent weld after heat welding, use a pipe wire brushto remove any defects or weld slag. This prepares the metal for each solder layer. Narrow-faced wire wheels are a good solution to this problem. If the V-groove of the welded joint is wider (for example, a larger diameter pipe passes through the packing), select a pipe wire brush with a wider surface for cleaning larger areas.
When two welders are working on opposite sides of a pipe of a larger diameter pipe, the start and end points of each welder are typically at 12 and 6 o’clock. The point at which the weld joints are joined and overlapped is called a button. Although this area may be more difficult to clean, avoid hitting the wire on the button as this will damage the wire. Use atmospheric pressure to give the wire pipe brush more time to clean the area.
The same wire wheel for inter-channel cleaning can also be used to clean the weld and remove all slag from the cover.
Some reels use a double hex nut design that simplifies the periodic flipping of the wheel and helps to improve the self-sharpening ability of the thread. Choosing the wheel of this design helps to maximize the cleaning effect, long life and safer use.
Another option for cleaning between weld beads is the packaged rail wheel. Only the wire lead is exposed from the package. These pipe wire brushes have several advantages, including longer product life and aggressive cleaning. And because there are no long wires outside the package, long wire breaks are eliminated.
Please note that the operator’s flexibility in using a closed cup wheel brush poor due to the short trim length of the wire. When selecting this option, look for a package wheel that uses a thermally stable package that will wear out to expose a consistent short decoration. This makes it suitable for cleaning heat welding without overheating.
Main safety practice
Following the right safety procedures can help maximize product performance and efficiency while helping to provide a safer environment for operators and nearby workers.
Regardless of which product is used, operators should always use tool guards to increase safety and wear appropriate safety equipment such as face and eye protection and gloves. Most manufacturers’ tools and accessory instructions contain specifications for recommended safety gears.
In addition, ensure that the grinding wheel or grinding wheel’s speed rating meets or exceeds the grinder’s recommended speed rating to ensure the safest use. Just because the product is suitable for a particular tool does not mean that the product can be used safely.
A harder bonded wheel is susceptible to load, which means that the base material accumulates on the grinding wheel due to heat during the grinding process. Some operators create chips or gaps around the edges of the wheel to clean the loaded wheel, but this is a dangerous practice that can cause flying debris to fly. Instead, look for pipes with proper strength for pipe welding.
Ultimately, quality and productivity are important – but safety is paramount. Choosing the right product to prepare and clean the base material for welding and following some key best practices can help extend product life, increase operator efficiency and benefit pipeline site safety.