Tired Of Spending Too Many Hours And Too Many Dollars Dealing With Scrap? We can help!
Key Factors That Affect Scrap on a Tube or Pipe Mill
No one likes scrap! However, there are many issues to consider when it does happen. There could be a number of causes. Below are a few of the reasons found most frequently.
- Inconsistent incoming material, which includes chemistry, slit edge condition, strip width-to-gauge tolerance, crown, and camber. It is important to maintain ordering and receiving standards at all times to identify and avoid these core complications.
- Improper end welds. Ensure end welds are sound, will not break, and have a low profile, so they cannot damage tooling or mill components as they pass through the mill.
- Misalignment of entry strip to first breakdown. Off-centered strip will result in improper forming, especially with modified edgeform and “W-style” designs.
- Improper setup. Tooling which is not set up according to a setup chart cannot perform as designed. There is no certainty derived in setting up a mill totally by feel, or using a “seat of the pants” technique.
- Insufficient cooling section. Does the tube have enough interface time in the cooling section to allow proper cooling before it reaches the sizing section? If not, bowed tubing will result after the tube cools down, resulting in scrap or the necessity of rework.
- Worn tooling. Do you have a formal tooling maintenance program in place? Do you know when to send your tooling in for rework? Worn tooling is a major cause of quality and scrap issues.
- Insufficient or non-existent preventative maintenance (PM) programs can result in poor integrity/condition. Are your mills scheduled for maintenance at regular intervals, or is your maintenance on a “crisis management” system? It can make a difference.
- Poor mill alignment. When was the last time the mills were aligned? The standard in the industry is to have mills aligned annually or after performing any major preventative maintenance.
- Failing to document a good setup. When you properly document a good setup, and then return to those numbers when running the same size in the future, you will consistently reduce time and scrap. Single-Point Adjustment (SPA) features and digital readouts on all stands, driven and idle, can save as much as 75% on setup time and even more on scrap.
- Improper tooling designs. Are you using yesterday’s designs for today’s new material properties and quality requirements? When was the last time your tooling designs were evaluated? Proper tooling design can certainly improve production and reduce costs by reducing scrap.
- Inadequate or lack of formal training. How long has it been since your personnel was formally trained in proper mill maintenance, alignment, setup, operation, and tooling maintenance? Do you have standard operating procedures (SOP) in place for all these areas?
- Inadequate exit, material handling equipment. Is your prime tubing coming off an old dump table system that bends, scratches, or damages your finished product before it can even be properly bundled? Are your bundling carts and racks designed and set up for efficient end product handling and removal? Is an upgrade in order?
Addressing each of these issues can go a long way towards preventing scrap. Of course, there is no way to completely eradicate it, but keeping it to a minimum can provide great benefits.
Check out the other areas of our website to learn how we can help your company correct or avoid these deficiencies.