Do you face such problems when working with engineering plastics? To save you from worries, here are some solutions.
How to solve the problem of large diameter PEEK rod cracking during drilling?
Large-size PEEK rods generally need to be drilled first when machining rollers and sleeve bearing such parts. If not follow the machining specifications, it is easily cause PEEK rod to crack.
1. Drilling with a large size drill bit directly
2. The drill bit was not repeatedly withdrawn when drilling the deep holes.
3. Insufficient cooling
4. Too fast feeding speed
5. Failure to sharpen worn drill bits in time
1. Drilling first with a small drill bit less than 10mm. Boring hole with a small boring cutter firstly then use bigger one. 2. Repeatedly withdrawn bit to remove the chips. 3. To ensure cooling enough and in time to reduce heat 4. Reduce the feeding speed. 5. Sharpen the drill bit in time 6. For large diameter PEEK rods, it can be cut and roughed firstly then heat treated and then finished.
How to solve the problem of bending deformation of PEEK valve plate during machining?
PEEK is an ideal choice material of valve plate for reciprocating compressor due to its self-lubricating, excellent impact resistance, wear resistance, light weight and other advantages.
The concentricity and flatness of the valve plate are required to be very high. How to prevent PEEK from bending deformation during machining is very important.
1. Rough machining the PEEK rod after cutting and then heat treatment to remove the internal stress of PEEK.
2. The process of PEEK gradient heat treatment can be referred to as follows: heating to 150°C and keeping it for 3h, then heating at a rate of 10°C/h, until the equilibrium temperature exceeds the long term using temperature of the PEEK （such as 265°C ）, and holding it for 4h (the specific residence time depends on the thickness of the PEEK product , About 1h per 5mm), then cool down at a rate of 10°C/h until it is below 140°C, and finally cool to room temperature naturally.
3. Control the semi-finished product tolerance margin, and use symmetrical machining to the required size.