Necessary conditions for producing high-quality Pipette tips
Pipette tips are the most common supplies used in the laboratory. Requires high dimensional accuracy and good concentricity, at the same time, the inner wall requires smooth no flow marks, and the tip is non notched burr.
Let us explain the process points from the manufacturing process:
1 production environment selection
Tips should be used in molecular detection, in vitro diagnosis, pre screening and other experiments, so pipette tips are more environmentally demanding for production, such as the presence of foreign organisms on the surface of the tips can directly affect the analysis results. Currently, one hundred thousand level dust-free workshops are the routine choice.
2 production equipment selection
The tip products have many holes, deep cavity, thin wall and fast molding cycle, which should have high molding efficiency, low failure rate and long-term stable operation in terms of equipment selection, therefore, high-speed electric injection injection machine is the superior choice, with the following characteristics:
*The high-speed electric injection molding machine meets the requirements of precision thin-walled articles, reducing the stress lifting pipette tip straightness formed by the pipette tip during molding;
*Open mode speed and precision are more stable to automated manipulator grasping product position;
*Stability and higher reproducibility. Motor the multi power system is controlled by a stand-alone system and the mold allows simultaneous action.
3 process considerations
The main undesirable phenomena of tip products are head missing, bending deformation, head and mouth hair edges, dimensional stability and other problems. In response to the above issues, the following points need to be noted in the actual production process:
*Reasonable ejection velocity.
Too fast will lead to air leakage and glue in the tip, and the gas cannot be discharged smoothly. Too slow will lead to large internal stress in the product, the product is bent, and the straightness is not enough. Should gradually use the ascending mold, and the product status to rational observation to select.
*Raw material related
① Materials with better flowability were selected for verification of the underlying parameters, which made rapid filling of raw materials convenient, selection of reasonable pressure as well as protection of precision mileuses and reduced the probability of bad looking phenomena.
② Reasonable temperature. PP raw materials belong to crystalline materials too low temperature will lead to the appearance of materials slow crystalline products hazed and opaque, products become brittle and other undesirable phenomena, too high temperature will lead to the degradation of raw materials strength.
*Reasonable V / P switching
In order to ensure relatively balanced injection, product commissioning should fill up gradually from short ejection, short ejection products need to carefully observe the balance and tip filling eccentricity. And designing rational V / P switching. Avoid situations such as glue deficiency of the pipette tip, hair edges, lack of straightness, etc.
*Automation
① For the suction automated action, a negative pressure gauge should be installed to monitor the vacuum size change value, while setting a reasonable vacuum range and equipment linkage, to achieve the abnormal action when the protection of the mold and the auxiliary detection of product breakage.
② Draw the amount of gas from the appliance plate to be adequate, taking the larger line as much space as possible.
③ The holder pipe body selects the plastic material + buffered structure as much as possible.
Post time: Dec-08-2022