Manufacturing technology of standard wet blue from wet salted cow hide and Goat hides

Raw material: Take wet salted cow hide (good selection).

Trimming: By hand knife. Take salted weight (All % based on this salted weight)
Now see the chart of the operations step by step of the tanning with chemical used, time required and analytical test.

Tannery

Operation	% of chemical use	Time	Analytical test
Pre-soaking	300% water 0.2% soda ash 0.2% LD 600	Run 60 minutes Drain
Main soaking	300% water 0.4% soda ash 0.3% LD 600 0.2% preservative	Run 30 minutes Leave overnight, next day drain wash well
Liming	300% water 4% lime 3.5% sodium sulphite 1% liming auxiliary 0.2% LD 600	Run 30 minutes Leave the bath for 2-3 days Then scudding by hand
Chemical wash	200% water 0.25% meta bi-sulphate	Run 20 minutes Drain
Deliming	100% water 1.5% ammonium chloride 1.5% ammonium sulphate 0.5% meta bi-sulphate	Run 45 minutes	Check with phenolphthalein
Bating	100% water 1% batting agent 0.5% wetting agent	Scudding, wash well Run 60 minutes Drain	Check: Thumb and Bubble test
Pickling	80% water 8% salt 0.2% impropel CO 0.5% formic acid 1.2% sulphuric acid 0.5% hypo	Leave ovewnight Run 15 minutes Run 30 minutes Run 2 hours Run 30 minutes Drain half pickle bath	Check pH
Chrome tanning	4% Basic chromium powder+ 4% basic chromium powder 1% sodium formate 0.5% OCS 50% water	Run 30 minutes Run 60 minutes	Check: Penetration 100%
Basification	1.2% sodium bi-carbonate 0.2% preservative	Run 90 minutes Run 60 minutes	Check final temperature 28 - 40 degree celcius pH = 3.7 - 3.8

After completing the above operations, assess the wet blue.
Assessment:
1. Boil test
2. Shrinkage temperature
3. Chromic oxide estimation
4. Grading and selection
5. pH check

Goat hides: The process of manufacturing technology if standard wet blue from salted goat hides is same as Cow hides except that there is an additional operation  in goat hide called Painting. 
Paiting chemicals that required are as follows -

Painting	8% lime 2% sodium sulphite 0.2% LD600	water requires to make as paste. 4-6 hours or overnight