300 mm with edm machining.

Thankyou Prof. Daniel.

Could you please provide any reference of it. 

The maximum drilling depth is more than 1 mm. This stuff from the machines you have and the tooling. The maximum drilling depth with standard tooling can be up to 380 mm.

Here you can find references:

http://www.excel-precision.co.uk/edm-drilling/

Another reference:

http://www.techniformedm.com/spark-drilling

I think this is the best reference:

https://www.americanwireedm.com/edm-services/edm-hole-drilling

Prof. Daniel,

Thankyou for the reply.

The links you have shared are reporting the drilling capability of their machines (i.e. maximum thickness of the workpiece that can be fixed) not the actual depth of hole achieved. 

https://www.americanwireedm.com/edm-services/edm-hole-drilling 

They utilize state-of-the-art, CNC-operated EDM machinery to drill blind- or through-holes as small as 0.005” in diameter in materials as thick as 11.61”. In Frequently asked questions,  it is reported that the smallest hole they can drill is of diameter 0.279 mm and depth less than 3.175 mm.

http://www.techniformedm.com/spark-drilling 

Drilling capabilities range from 0.3mm to 3mm in diameter through a depth of 300mm.

http://www.excel-precision.co.uk/edm-drilling/ 

EDM Drilling Capacity - Our EDM drilling machines can drill holes 0.5mm – 3mm in diameter and up to 400mm deep.

The report of any research article will be beneficial to find the answer.

Dr.Emil, 

Thankyou for the comment.

Reference of any research article will be highly appreciated.

Mr Ravinder. Certanly I give general information. Then, with this information, if you want, you can contact edm machine manufacturers to resolve your need.

Equally I try to search one paper.

Can you read this papers please?

I have gone through these articles earlier.

Thankyou Prof. Daniel for valuable time and help.

Another one.

Hello dear friends

The data provided by the manufacturers are quite nice, but also very general. If I ask the question of a maximum hole reduction, then also must be indicated, in which quality the hole is to be produced. According to Haas, Munz and Risto, depths of up to 1000 mm are possible, but with what reproducibility? With a diameter of 0.5 mm, a diameter deviation of more than + - 30 μm is achieved with the EDDM, without taking into account the diameter deviation between the inlet and outlet holes. With increasing depth, it is a problem to guide the tool electrode (in the normal case 0.25 to 0.3 mm diameter) stably, so that the hole is also moved from the ideal guide line.

If one thinks about these things and perhaps the questions about the inner roughness and the parallelism with several holes, the applications are often reduced very quickly. In most cases, productivity is rapidly reduced when high hole quality is required. However, the critical boundary conditions at 1 mm hole diameter are already considerably smaller and can be handled.

In principle, one should also keep in mind that such deep holes can be produced with ECM, in which case greater effort must be made for the tool. According to my knowledge, the good results are then about 100 mm.

Dr. HP Schulze,

Can you provide any reference showing EDMed hole depth greater than 20 mm for the electrode diameter of less than 1 mm. 

Check this out:

http://www.sciencedirect.com/science/article/pii/S0007850613001169

Thankyou Mr. Krishna Kumar Saxena.

Thanks all of you

I think it depends on which of non-conventional machining process (ECM,EDM,Laser ) was used and cutting conditions.