Vane Pump
Vane Pump
a positive-displacement pump with reciprocating rotary motion of the operating member; it is used to pump fluids. The cylindrical housing of a vane pump contains a rocking rectangular vane with delivery valves, which acts like a piston, and partitions with inlet valves. Oscillatory motion is usually imparted to the vane by hand, and the fluid is sucked in and forced out. Double-action vane pumps have come into common use for pumping various fluids containing no abrasive contaminants (water, petroleum products, and so on) for short periods. They can deliver 2–12 m3/hr, with a head of 10–20 m.
| Table 1. Most common varnishes and some of their properties | |||||
|---|---|---|---|---|---|
| Drying conditions | Material of substrate | Adhesion of coating to metal | Conditions of use | ||
| temperature (°C | time (hr) | ||||
| 1Dry upon addition of catalysts | |||||
| 2Dry upon addition of hardeners | |||||
| 3Reversibility of films is caused by the absence of reactive groups in the film-former (for example, a copolymer of butylmethyl acrylate with other acrylates) | |||||
| Varnishes that form irreversible films Oil.................. | 18-20 | 24 | metal | good | indoors and outdoors |
| Oil-bituminous........... | 120-200 | 0.5-2.0 | metal | good | indoors and outdoors |
| Alkyd ............... | 18-2080-160 | 24-48 1–4 | metal metal | good good | indoors and outdoors |
| Polyester.............. | 18-2060-70 | 24 0.5-1.0 | wood | _ | indoors |
| Urea-formaldehyde1 ...... | 18-20 | 2 | wood | indoors | |
| Urea-alkyd............ | 100-130 | 1.0-1.5 | metal | satisfactory | indoors |
| Melamine-alkyd ......... | 90-130 | 0.5-1.5 | metal | satisfactory | indoors and out- |
| Phenol-formaldehyde (resol) | 18-20 | 24 | metal | satisfactory | doors indoors at |
| Phenol-oil............. | 18-20150-180 | 24 1–2 | metal | good | temperatures up to 160°-170°C; in alkalies and acidsindoors and out- |
| Epoxy1 .............. | 150-190 | 1-3 | metal | good | doors indoors at temperatures up to 160°-170°C; in alkalies and acids |
| Polyacrylic............ | 80-150 | 0.5-2.0 | metal | good | indoors and outdoors |
| Polyurethane........... | 18-20 | 2-24 | metal and wood | good | indoors and outdoors |
| Polyvinylacetal2......... | 18-20 | 3-5 | metal | good | indoors and outdoors |
| Silicone............... | 150-200 | 1-2 | metal | satisfactory | at temperatures |
| Varnishes that form reversible films | |||||
| Shellac (alcohol)............... | 18-20 | 2 | wood and glass | - | indoors |
| Bituminous (asphalt)............... | 18-20 | 3 | metal | good | indoors |
| Nitrocellulose ................. | 18-20 | 1 | metal and wood | poor | indoors and outdoors; in gasoline |
| Perchlorvinyl............ | 18-20 60 | 1.5-3.0 1 | metal and wood | poor | indoors and outdoors; for short periods in acids and alkalies |
| Polyacrylic3 ............ | 18-20 | 1-4 | metal | good | indoors and outdoors |
Vane Pump
a type of a positive-displacement rotary pump whose working elements are a rotor, which rotates in an eccentrically bored stator, and vanes inserted in longitudinal grooves of the rotor and held against the stator by centrifugal force, springs, or the pressure of the liquid supplied from the direction of the rotor axle.