1. Why do profile dimensions still “behave” differently with the same machines and billets?

Many Iraqi extrusion plants share the same experience:

• One batch of profiles meets dimensional specs very well; the next batch, with the same process settings, starts drifting.

• Sometimes wall thickness is slightly heavy, sometimes diagonals are slightly large; a single batch doesn’t look terrible, but the accumulation leads to assembly issues.

• Export customers are extremely sensitive to fit and clearance, and even small variations trigger complaints or claims.

This kind of small but persistent dimensional drift is often not a pure machine-accuracy issue. More commonly, it is caused by inconsistent die stiffness and nitriding quality: with the same steel and geometry, differences in nitrided case depth, hardness distribution and residual stress make each die behave differently during extrusion.

2. If dimensional issues are bothering you, what type of situation are you in?

Before you invest in a Φ700×900 mm nitriding furnace, it’s worth taking a quick snapshot of your situation:

• Is heat treatment fully outsourced or done in-house with a small furnace?
  If outsourced, have you ever seen detailed process reports? Do you observe large batch-to-batch differences?

• Do dies fail “suddenly” or “softly”?
  Are you seeing catastrophic chipping and breakage, or a gradual loss of control as the die seems to “soften” over time?

• Do you systematically link dimensional data to die batches?
  Or does every dimensional problem end up being discussed on the shop floor based on guesses?

If you realize there is almost no data link between die condition, nitriding process and dimensional performance, it means you lack not only a Φ700×900 mm nitriding furnace, but also a basic data framework for die nitriding and dimension control.

3. Under Iraqi conditions, how should you choose a Φ700×900 mm nitriding furnace to really help dimensional stability?

When picking a Φ700×900 mm effective-size nitriding furnace, you shouldn’t just focus on “how many dies can it hold”, but rather whether it truly supports dimension control:

1. Chamber size vs. typical die loading pattern

   • Can Φ700×900 mm hold a full set of your main die families in one batch?

   • Can you realistically run “one batch = one die family”, instead of mixing all kinds of dies and compromising the recipe?

2. Recipe management for different steels and die families

   • Can you build separate nitriding recipes for different die steels and profile series?

   • Can you record and export temperature, time and nitriding potential for each batch for comparison and optimization?

3. Proven temperature and nitriding potential uniformity

   • The smaller the temperature gradient and nitriding potential fluctuation, the easier it is to reproduce nitrided case properties and keep die stiffness consistent.

   • A Φ700×900 mm furnace without solid data on uniformity is just “nice on paper” and unlikely to meaningfully improve dimensional stability.

When comparing vendors, turn these three points into a short checklist and ask each supplier to respond with real data. Suppliers like Wuxi Wondery Industry Equipment, when delivering a Φ700×900 mm nitriding furnace, will typically also provide basic process suggestions and tuning experience to help shorten your ramp-up period.

4. After installing a Φ700×900 mm nitriding furnace, how will profile dimensions change?

Once furnace selection and recipes are solid, most plants see changes like:

• More consistent die behavior across batches
  Key dimensions such as wall thickness and diagonals cluster within a narrower range; extreme “very good vs. very bad” batch swings become less frequent.

• Shorter trial time and smaller adjustment windows
  Process engineers have more confidence in die condition and can fine-tune extrusion parameters within a smaller range, instead of reserving large safety margins.

• More positive feedback from export customers on dimensional stability
  When you can show several consecutive batches of dimensional statistics linked to specific die and process settings, customers are more likely to recognize your process control capability rather than judge you on a single batch.

Over time, these improvements show up in lower rejection rates, stronger customer loyalty and better chances of winning new business.

5. What preparation can you start with right now?

Even if you are not ready to purchase a Φ700×900 mm nitriding furnace immediately, you can start laying the groundwork:

1. Create a simple “die batch – dimension data” mapping
   Start with a few key orders: record die number, heat-treatment batch and key measured dimensions.

2. Compile current die steels and size ranges
   List the steel grades, outer diameters, heights and typical product profiles for your main dies.

3. Roughly summarize your current outsourced or in-house heat treatment parameters
   Even incomplete information (temperature ranges, hold times) is better than nothing.

With these materials, when you talk to suppliers about a Φ700×900 mm nitriding furnace, the more professional they are, the more clearly you will hear it. Your requirements are more likely to be translated into real process and equipment configurations, rather than being treated as a generic “we want to buy a furnace” request.