How to use a machining center to process flanges?

Recently, a customer from Serbia needed to purchase a machining center to process flanges. The flange to be processed was the national standard flange DN100. The standard center hole of DN100 is 108mm, the outer diameter is 215mm, the thickness is 24mm, and the number of bolt holes*diameter is 8*18. The customer is from a local mechanical parts processing manufacturer. Processing high-precision industrial parts for local customers.

ANTISHICNC engineers successfully matched a machining center-VMC650 for the customer. The travel of X, Y, and Z axes is: 800*450*500mm. The spindle taper is BT40, suitable for milling holes, face milling, tapping and other processes. Under the advice of Shanghai Antis engineers, the fourth axis (indexing plate) was added to facilitate the sub-processing of bolt holes in one clamping.

Shanghai ANTISHICNC VMC650 machining center is suitable for batch processing of small parts and multiple varieties. It is the first choice of customers.

The VMC650 machining center has high rigidity, extremely stable precision and is equipped with a high-performance CNC system. The machine has complete functions, high automation, simple operation and high reliability. It can realize X, Y and Z three-axis control and can process various complex small and medium-sized parts. It is an extremely ideal mechanical equipment.

The following are the basic parameters of VMC650:

Next, the Shanghai ANTISHICNC engineer will briefly introduce to you the simple process of VMC650 processing DN100 flange:

1. Preparation
Drawing confirmation
Confirm the flange standard (such as GB/T 9119-2010), size (DN100 outer diameter is about 220mm, number/diameter of bolt holes, etc.), material (commonly used Q235, 304 stainless steel, etc.) and processing requirements.

Material preparation
Select round steel or flange blanks of appropriate diameter to ensure sufficient margin (such as φ230mm round steel).

Tool preparation
End mill (rough/finishing), drill (bolt hole), boring tool (inner hole), chamfering tool, etc.

Jig preparation
Use a vise or special fixture to ensure that the workpiece is stable (flange thickness and force during processing need to be considered).

2. Processing process
Clamping and tool setting
Clean the workbench and workpiece, and calibrate the fixture with a dial indicator.
Clamp the workpiece in the center to ensure that the Z-axis processing depth covers the flange thickness (usually 16-20mm).
Tool setting sets the workpiece coordinate system (G54) and enters the tool length compensation.

Rough machining
Milling the outer circle
Use a φ20mm end mill to rough mill the outer circle to ≈222mm (leave a finishing allowance of 0.5mm).

Milling the end face
Mill the upper and lower end faces flat, and control the total thickness to the drawing size (such as 18mm).

Rough machining of the inner hole
Use a keyway milling cutter or an end mill to open the inner hole to ≈102mm (leave an allowance).

Fine machining
Fine milling of the outer circle
Change the fine milling cutter and process to φ220mm (national standard DN100 flange outer diameter).

Fine machining of the inner hole
Bore to φ110mm (DN100 nominal diameter is 100mm, the inner hole needs to be slightly larger).

Bolt hole machining
Use a center drill to locate and drill 8×φ18mm bolt holes (evenly distributed on the φ180mm circumference according to the standard).

Chamfering and deburring
Chamfer the inner and outer edges C1-C2 (45°), and deburr the bolt hole mouth.

Inspection
Measure the outer diameter, inner hole and thickness with a caliper.
Check the bolt hole position with a thread gauge.

3. Notes
Clamping deformation: Thin flanges need to be lightly pressed or padded with equal height blocks to avoid milling deformation.
Tool wear: Stainless steel materials need to reduce the speed and check the tool regularly.
Program verification: The first piece is run in single-stage mode, and batch processing is performed after confirmation.

If you have any questions, please contact Shanghai ANTS Machiner Equipment Co., Ltd. through our website information. Engineers will match you with efficient machine tools and professional services.

Keywords: Precision machining, turning and milling, machining center flange