Spade bits are used for rough boring in wood. They tend to cause splintering when they emerge from the workpiece. Woodworkers avoid splintering by finishing the hole from the opposite side of the work. Spade bits are flat, with a centering point and two cutters. The cutters are often equipped with spurs in an attempt to ensure a cleaner hole. With their small shank diameters relative to their boring diameters, spade bit shanks often have flats forged or ground into them to prevent slipping in drill chucks. Wood Spade Drill Bit,Fat Drill Bit,Paddle Drill Bit,Wood Drill Bit Behappy Crafts (suzhou)Co.,Ltd , https://www.craftsbehappy.com
Some bits are equipped with long shanks and have a small hole drilled through the flat part, allowing them to be used much like a bell-hanger bit. Intended for high speed use, they are used with electric hand drills. Spade bits are also sometimes referred to as "paddle bits".
Spade drill bits are ordinarily available in diameters from 6 to 36 mm, or ¼ to 1½ inches.
There are many mini pumps, mini liquid pumps, small pumps, pump pumps, self-priming pumps, etc. in the market. It is dazzling. How to select suitable models? The main parameters are: "flow rate" and "pressure". Selection criteria exactly what criteria to choose? According to the following principles to choose. First, the working medium at room temperature (0-50 ℃), simply pumping water or solution, not water vapor dual use, but requires self-priming capability, and the flow and output pressure requirements. Description: The working medium is pumping water, non-oily, not strong corrosive liquid solution (can not contain solid particles, etc.), must have self-priming function, you can choose the following pumps: 1, the flow requirements of a larger L / min), the pressure is not demanding (about 1 to 3 kg), mainly used for water circulation, water sampling, upgrading, etc., require noise, long life, high self-priming suction, etc., the optional BSP, CSP series ; 2, the flow of less demanding (about 1 to 5 liters / minute), but the pressure is large (about 2 to 11 kg), mainly used for spraying, pressurization, car washing do not need long hours of work under high pressure or heavy load ASP, HSP and other series can be selected; 3, for the tea table pumping, spraying, etc., the required volume as small as possible, the flow requirements of small, low noise (about 0.1 to 3 liters / minute) . Second, the working medium at room temperature (0-50 ℃), the need for pumping water or gas (which may be mixed water or air, dry turn occasions), value the volume, noise, continuous use and other properties. Pumping is mainly done by using micropumps but it is not desirable to manually add "water diversion" before pumping (some pumps need to manually add some "water diversion" before working so that the pump can pump the water downwards, otherwise the pump can not pump or even damage) , I hope the pump has "self-absorption" function. At this point you can choose PHW, WKA series products, their strength is that: In the absence of access to water, it is a vacuum, the formation of a vacuum by air pressure up, and then began pumping. With the above application, you can choose PHW, WKA series. Third, the working medium of high temperature (0-100 ℃), such as miniature pumps for water circulation cooling, water cooling, or pumping high temperature, high temperature steam, high temperature liquid, you must use micro-pump (high temperature type) Caixing: Temperature: 50-80 ℃, you can choose micro-gas dual-use WKA series high temperature medium type, the maximum temperature is 80 ℃ or 100 ℃; 2. If the temperature: 50-100 ℃, it must be Use WKA series of high temperature medium type, the maximum temperature is 100 ℃ temperature; (when the extraction of high temperature water (water temperature exceeds about 80 ℃), due to the precipitation of gas in the water, will greatly reduce the pumping flow, the specific reduction to the number of flow, please See here: (This is not a pump quality problems, please pay attention when selecting!)) Fourth, the flow of greater demand (more than 20 liters / minute), but the medium contains a small amount of oil, solid particles, residues and so on. (1) Where self-priming is not required and the pump can not be placed in water, the solid particles can be cut into smaller particles: the FSP Ultra Flow Series can be selected. (2) need self-priming, and the pump can be placed in the water, the optional submersible pump QZ (medium flow 35-45 liters / minute), QD (large flow 85-95 liters / minute), QC 145 liters / minute) three series of miniature submersible pumps, DC submersible pumps.