ypical 1. Excellent SAE port  machining 
Typical 2. High roughness request 
Typical3. J.B special skill for perfect de-burring

J.B Advantage Techinique Analysis    　
1. The mark ① is the mouting hole for cylinder with  self-lubricating bearing. It has strict request of Geometric Tolerance. The roughness is at least Ra3.2μm
2. The mark ② is SAE port with strict  conical surface roughness request and dimensional accuracy request. It is one of the most typical technique point for hydraulic cylinders 
3.The mark③is the bufferring port for protecting the cylinder. So the surface roughness,hole roughness and precision are all the the typical technique of J.B 
4.The mark④ is the connecting part or teminal part for cylinder bottom.  The request roughness is Ra3.2μm with high request machining tolerance
5. Besides, there is one bufferring hole at the bottom of cylinder. Its roughness is request is at least  Ra3.2μm; The dimensional tolerance must be not more than 0.1mm
6.J.B special skill for perfect de-burring