Classes or Function modules to create HU in EWM

Hi Experts,

Is there any Classes or Function modules to Create Handling Units(HU) in EWM.

from this i am requesting your ideas to full fill the current scenarios.

As i am new to EWM Process, i found some of the methods but those are not working for me.

In My scenario i need to create a handling unit by using inbound delivery and combine that into another HU.

I found these:

                    /SCWM/CL_DLV_PACK_IBDL

                    /SCWM/CL_WM_PACKING

Could any one please let me know how to process with this.

Thanks in advance,

Venubabu Divvi