anticlockwise milling and clockwise milling

Milling is one of the most common and most widely used processing methods, and for roughing milling of the various structural components and fine milling is almost by end milling. There are two ways, clockwise and anticlockwise milling, according to the cutting direction. The movement of the cutting edge and work piece is in the opposite direction or same direction, divided into the two kinds of conventional milling and climb milling.

Anticlockwise Milling:

Milling direction and feed in the opposite direction (milling against the feed) is anticlockwise milling; chip caused from the bottom into upper, so we also call it as up milling; Since the traditional processing and milling mostly used this way, so we also called it as conventional milling.

Characteristics of anticlockwise milling:

1. Chip shape is from thin to thick, and cutter afford force from light into heavy, which may prevent the cutter fracture by the impact.
2. Suitable for milling casting black surface.
3. Can be used in the old milling machine, no screw invalid gap movement.
4. More friction, the blade is easy to blunt, short life.
5. Easy shaken, the machined surface is rough, poor machining accuracy.
6. The device is not easy to settle, which is not suitable for milling thin parts.
7. More energy consumption.

---

Clockwise milling:

The milling and feed in the same direction (milling with the feeds) called clockwise milling; Due to cutting action is from no-machining face of work piece into down place (chips from thick into thin), so it is called down milling or climb milling.

Characteristics of climb milling:

1. Chip is from thick into thin, cutter affords force from heavy into light, easy to cause fracture by impact.
2. Not suitable for milling castings, forgings, and the surface of the work piece with fish scale shape.
3. The milling machine shall have a gap eliminator, or easy to produce screw invalid gap movement.
4. Processing less friction, longer life of the cutter edge.
5. Easy chucking, no vibration, and high accuracy of the machined surface.
6. The device is easy to settle, it’s suitable for milling long thin work pieces.
7. Less feed consumption.

In most of the milling case, in addition to the casting of the first milling and old milling Lo-gap chopping device need to

use the anticlockwise milling, down milling is better than conventional milling.

 

Cutting Reference Data for End Mills of Various Materials

Effective working solution depends on correct cutters, operation method, and technology.

Usual cutting conditions and major influence factors of CNC machines.

	Introduction	Formula
Cutting Data V(m/min)	Cutting speed is decided by the diameter of end mills and its rpm		V=Cutting speed(m/min) D=diameter(mm) N=rpm of one min of end mills(min-1)
Feed speed F(mm/min)	Feed speed is the speed of relative one of work piece. Feed rate per flute is important for multi-flute end mills.		F=Feed speed per minute z= number of flute f= Feed volume per flute
Cutting depth a(mm)	Cutting depth is the thickness of flute machining on work piece. We always increase cutting depth to achieve its efficiency, but it is too deep to short tool life. It’s better to give proper cutting depth per flute, don’t increase feed rate and cutting depth together.	—	—
Feed rate per flue f(mm/刃)	Once a flute to cut	—	—
Cutting width b(mm)	Vibration caused by diameter of end mill, width of work piece, flute numbers, and cutting width.	—	—

Cutting Speed

Work Material	High Speed Steel	Carbide – rough cutting	Carbide – fine cutting
Cast iron (soft)	32	50-60	120-150
Cast iron (hard)	24	30-60	75-100
Malleable cast iron	24	30-75	50-100
Steel (soft)	27	30-75	150
Steel (hard)	15	25	30
Aluminum alloy	150	95-300	300-1200
Yellow Steel (soft)	60	240	180
Yellow Steel (hard)	50	150	300
Bronze	50	75-150	150-240
Copper	50	150-240	240-300
Hard Rubber	60	240	450
Fiber	40	140	200

Feed volume each side

Working Material			Face cutter		End Mill		Spiral flute flat end mill		Side Cutter		Milling Cutter		Metal gap cutter
			HSS	Carbide	HSS	Carbide	HSS	Carbide	HSS	Carbide	HSS	Carbide	HSS	Carbide
Cast Iron	HB150-180		0.4	0.5	0.2	0.25	0.32	0.4	0.23	0.3	0.13	0.15	0.10	0.13
	HB180-220		0.32	0.4	0.18	0.2	0.25	0.32	0.18	0.25	0.1	0.13	0.08	0.1
	HB220-300		0.28	0.3	0.15	0.15	0.20	0.25	0.15	0.18	0.08	0.1	0.08	0.08
Malleable cast iron, Cast iron			0.3	0.35	0.15	0.18	0.25	0.28	0.18	0.2	0.1	0.13	0.08	0.1
Carbon steel	Cutting steel		0.3	0.4	0.15	0.2	0.25	0.32	0.18	0.18	0.23	0.13	0.08	0.1
	Soft steel, Steel		0.25	0.35	0.13	0.18	0.20	0.28	0.15	0.2	0.08	0.1	0.08	0.1
Alloy Steel	Annealing robust steel	HB180-220	0.20	0.35	0.10	0.18	0.18	0.28	0.13	020	0.08	0.1	0.05	0.1
		HB220-300	0.15	0.3	0.08	0.15	0.13	0.25	0.10	0.18	0.05	0.10	0.05	0.08
		HB300-400	0.10	0.25	0.05	0.13	0.08	0.2	0.08	0.15	0.05	0.08	0.03	0.08
	Stainless steel		0.15	0.25	0.08	0.13	0.13	0.20	0.10	0.15	0.05	0.08	0.05	0.08
Al-Mg Alloy			0.55	0.5	0.28	0.25	0.45	040	0.32	0.30	0.18	0.15	0.13	0.13
Brass, Bronze		speedy cutting	0.55	0.5	0.28	0.25	0.45	0.4	0.32	0.3	0.18	0.15	0.13	0.13
		ordinary	0.35	0.30	0.18	0.15	0.28	0.25	0.20	0.18	0.10	0.10	0.10	0.18
		hard	0.23	0.25	0.13	0.13	0.18	0.2	0.15	0.15	0.08	0.08	0.05	0.08
Coppper			0.30	030	0.15	0.15	0.25	0.23	0.18	0.18	0.10	0.10	0.08	0.08
Plastics			0.32	0.38	0.18	0.18	0.25	0.30	0.20	0.23	0.10	0.13	0.08	0.10

 

蒙耐爾合金(Monel)

蒙耐爾合金又稱鎳合金，是一種特殊的合金，金屬鎳為基體添加銅、鐵、錳等其它元素而成的合金。蒙耐爾具有高強度、高耐蝕、耐磨損的優良的物理特性，呈銀白色，在各種酸、堿介質中，具有使用壽命長的優點，因而廣泛應用於石油化工、核工業、國防工業等尖端工業上，做為重要的零部件和其它高強度、高耐蝕、高耐磨特性的複雜環境條件下使用的行業。

蒙耐爾合金在多種介質中均有良好的耐蝕性，它在空氣、土壤、淡水和海水中都很穩定。在土壤中的腐蝕速度不大於0.0003mm／a；在海水中的腐蝕速度為 0.03mm／a。蒙乃爾合金在非氧化性酸(硫酸、鹽酸、磷酸、氫氟酸)、鹽溶液和有機酸中，也有較好的耐蝕性。但在通氣介質或有氧化劑存在時，耐蝕性顯 著下降。在室溫下，在80％以下濃度的硫酸和20％濃度的鹽酸中，其腐蝕速度小於0.5mm／a。在中等濃度的磷酸和氫氟酸中，直至沸點溫度仍能保持穩 定，僅次於鉑和銀。但對應力腐蝕敏感，使用前應進行消除應力處理。

Monel合金是Ni-Cu系耐蝕合金，有兩種類型：加工強化型，有Monel400、404、R405等牌號；沉澱硬化型，有Monel K-500、502等牌號，常用Monel 400和K-500、Monel K-500的力學性能優於Monel 400，但耐蝕性稍差。

資料來源：網路彙整