KOR-8 is the standard machine. KOR-12 can handle thicker tubes and higher reduction rates than KOR-8.
• Smooth, continuous, one-step reduction
• No pounding or vibration, causing off-centre coils
• Silent operation
• High production capacity
• Reliable design
• Auxiliary equipment available
• Automation in line possible
• Quick change between tube sizes
The machines consist of:
– Machine stand with motors and gear boxes
– Transmission shafts
– Bearing box assembly with rolls (ground steel or tungsten carbide)
– Simpler type of straightening device (other straighteners available on request)
The gear box shafts are connected by transmission shafts. The bearing box assembly is preparted for a specific diameter to diameter reduction. Changing bearing box assembly, in order to change to a new dimension, is made in less than 15 minutes. The rolls are made by either ground steel or sintered tungsten carbide. All rolls are running at the same speed.
The guide bushings are made of plastic. Brass bushings may give discolouration of the tube and stainless bushings may lead to ”welding”.
As a rule of thumb, sintered carbide rolls are recommended for annual productions of over 1 million meters of tubes of hard material. The life can be 5-10 times that of tool steel.
Some lubricant (oil or soap water) can be used to reduce bending of the element. Worn rolls increase bending.
As a rule of thumb, the minimum safety distance bewteen tubes should be 500 mm, or one third of the element length, in order to make place for elongation. If this is not respected, a failure may occur which may result in bent shafts, cracked bearings or cracked rolls
(sintered carbide rolls).