1, Renault regulator and its common faults
(1) The main regulator is clogged. Since the coke oven gas contains tar mist and corrosive gas, it is easy to cause corrosion of the main regulator and the valve port gasket. The surface of the valve body becomes rough due to corrosion, which provides conditions for the retention of tar, which tends to cause the main valve port to close, the pressure to rise, and the closing pressure of the medium-pressure auxiliary pressure regulator and the low-pressure auxiliary pressure regulator to rise. The main valve of the regulator is not closed tightly, and the medium pressure gas will enter the user in severe cases. In the winter, the ex-factory temperature of coke oven gas is about 70 ° C. After long-distance transportation, the temperature drops rapidly, and the frost-like snow-like tea crystals are condensed in the pressure regulator, causing serious closure of the main valve port, and medium-pressure assist. The regulator tea is severely blocked. When the low-pressure auxiliary pressure regulator has a plug, the pressure under the membrane of the pressure balancer is too low, resulting in a large amount of Cai in the guide seat of the shut-off valve, so that the shut-off valve port is not closed, thereby causing medium-pressure gas to enter the household.
(2) The failure phenomenon of the medium voltage auxiliary voltage regulator. The valve port of the medium pressure auxiliary pressure regulator is most easily blocked. As the crystal of naphthalene increases sharply, the valve port is blocked, the medium pressure gas cannot enter the pressure balancer as needed, the pressure under the pressure balancer membrane is lowered, and the lever is balanced. The gravity of the block moves down, causing the valve port of the main regulator to open, forming an overpressure air supply, which seriously affects the safety of the gas supply. The needle valve after the medium pressure auxiliary pressure regulator is blocked by the naphthalene crystal to form an overpressure supply failure. The reason for the overpressure gas supply is the same as that of the medium pressure auxiliary pressure regulator valve port. If it is not timely, the gas supply safety will be seriously affected.
2. Self-operated pressure regulator;
The self-operated pressure regulator has high manufacturing precision and strict technical requirements. However, the regulator has a single valve port structure, a small flow rate, and is unstable, and the signal tube is very thin, which is prone to failure for coke oven gas containing a high viscosity tar mist. Especially when the content of naphthalene in the winter gas exceeds the standard, it has a great impact on its normal operation. The blockage occurs mainly in the pilot nozzle and the adjustment lever of the main regulator. Because the pilot nozzle has a small diameter, it is easily blocked. When the nozzle is clogged, the gas flow rate is reduced, causing the pressure on the upper chamber of the main regulator membrane to drop, so that the valve port of the regulator is closed as the film rises, and the valve port is closed when it is severe, causing the failure of the gas supply to be stopped. . The adjusting rod and the catheter are manufactured with high precision and high roughness, and the matching clearance is small. Once the naphthalene vapor is condensed in the gap or in the upper and lower parts of the adjusting rod, the adjusting rod is easily caught. When the adjusting rod is stuck in the state of opening the valve port, an overpressure air supply will be formed, and in a serious case, the medium pressure air supply will be directly applied, which is extremely harmful. Practice has proved that the overpressure supply failure of the self-operated pressure regulator is caused by more. When the adjustment lever is stuck at a small opening of the valve port or is in a closed state, a failure of supplying air or stopping the supply of air may occur, which must be highly valued.
3, the treatment of countermeasures
3.1 Treatment of tar plugging failure
The condensate in the pipeline is discharged in time to minimize the corrosion of the regulator to the regulator. Reduce the roughness of the pressure regulator contacting the coke oven gas, so that the tar adhesion is reduced, thereby reducing the clogging failure caused by the tar.
3.2 treatment of naphthalene blockage failure
There are two main reasons for the blockage of naphthalene: one is that the temperature difference between the factory coke oven gas and the pressure regulator is large, and the other is that the naphthalene content of the coke oven gas is exceeded when it leaves the factory. The temperature of the pressure regulator is lowered while the pressure is reduced, so that the naphthalene crystal adheres to the inner wall of the pressure regulator. The main methods to prevent naphthalene crystallization are as follows:
(1) Electric heating belt insulation method. The solution to the precipitation of naphthalene gas from coke oven gas is to increase the saturated vapor pressure of naphthalene, that is, to raise the temperature of the pressure regulator, so that the saturated vapor pressure of naphthalene around the pressure regulator increases. At present, the method we adopt is to use electric heating belt insulation method. The installation method of the electric heating belt mainly has the following two types: one is a winding method, that is, the heating belt is wound around a key portion to be heated, and then a simple external heat preservation is performed. Another method is to apply parallel injections, that is, to apply one or more heating belts in parallel along the portion to be heated, and the outside is wrapped with a heat insulating material. The former method is simple to install, the heating belt is small in amount, and the power consumption is small, and the method is also used more. Both of the above methods can obtain good results and reduce the number of failures of the regulator during operation. However, after using the electric heating belt insulation method for a period of time, the probability of failure of the regulator has been reduced, but the failure phenomenon has also undergone some changes. The original snow-like blockage turns into white-faced naphthalene residue, which may be due to pressure regulation. The temperature of the device is high, so that the naphthalene is powdery.
(2) Radiator insulation method. A radiator is installed in the pressure regulator chamber and heated by a radiator. As a result, in the overhaul of the regulator for heating the radiator, no naphthalene crystal blockage was found, but there was still tar deposit.
(3) Keep the contact surface clean. For existing pressure regulators, clean the easy-to-block surfaces as much as possible during each inspection and keep them clean to avoid the retention and accumulation of naphthalene and tar due to roughness.
