Since the protector is a bimetal protector, although it has a good effect on the slow overload protection of the temperature rise, it has little effect on some cases where the temperature rise is severe in a short period of time. A large current is used to protect it. The thermal characteristics of the protector have a lag time for high current protection. In the stall state, the motor is blocked, and the adiabatic process is similar. The pressure and temperature in the closed chamber will increase rapidly at the beginning; at the same time, because the gas on the suction side is not replenished, the flow rate is also smaller (similar to vacuuming), compression. The work is reduced, and the pressure and temperature rise rate are slowed down. After about 1min, the temperature in the chamber can reach 250e, and the current is basically stable at the minimum value of 212A. At this time, the compression work tends to zero. The closed cavity of the compressor mainly relies on motor heating and mechanical friction to generate heat, which leads to temperature increase. The pressure also rises and the rate of increase does not change until the pressure reaches the stall condition.
The compressor motor is a single-phase asynchronous AC motor, which is operated by a capacitor running type. The maximum torque of the motor running is generally about 250 of the full load. When the load is too large, the compressor stalls. After the motor stalls, the compressor is blocked, the motor coil is heated, and the motor heat is increased sharply. The maintenance time is about 10s. At this time, the heating process is constant. At the beginning of the stall, more flammable and explosive gases have accumulated in the compressor, and the high temperature and high pressure in the closed chamber of the compressor greatly accelerate the decomposition and cracking of the motor insulation material. After the stall occurs, a large current flows through the motor coil. Once the insulation is weakened somewhere, the motor is prone to short circuit or high voltage discharge to generate sparks. The electric spark is a kind of external high-temperature heat source, so that the temperature of the local combustible mixture close to it rises to a critical state and is ignited by the fire, and then the flame is propagated to cause the entire mixture to ignite and ignite.
HDPE double wall corrugated pipe Appearance, standard and Application
Black. Implementation of GB / T1942.1-2004 "buried HDPE structural wall pipeline system section 1; polyethylene double wall corrugated pipe", the elastic ring meet the requirements of HG / T3091-2000. Products are widely used in urban drainage, sewage engineering, agricultural irrigation, drip irrigation, water-saving irrigation projects, drainage, sand control projects.
HDPE double wall corrugated pipe Specification
1. N4(ID 200 mm.300 mm.400 mm.500 mm.600 mm.800 mm)
2. N8 (ID 200 mm.300 mm.400 mm.500 mm.600 mm.800 mm)
HDPE double wall corrugated pipe Features
n Unique structure, high impact strength ;
n Smooth inner wall,small water flow resistant.large fluid flow;
n Easy to connect,good joint seal,No infiltration;
n Extremely light weight ,hence easy to handle and reduce cost;
n More than 50 years` service life in buried condition.
n High-density polyethylene is a hydrocarbon polymer, non-polar, high acid and alkali corrosion resistance.
n Eco-environment materials, non-toxic, non-corrosive, non-scaling, recyclable;
n Temperature range,-60â„ƒ the pipeline no breakage, the maximum temperature of the transmission -medium is 60â„ƒ
n Comprehensive project cost basically same as the concrete pipe, low operating costs
HDPE Double Wall Corrugated Pipe
HDPE Pipes,HDPE Double Wall Corrugated Pipe,High Density Polyethylene Pipe,Double Wall Corrugate HPDE Pipe
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