Reasons and improvement measures for gear pump faults and pipeline repair technology

Firstly, the causes of gear pump failures and improvement measures

(1) High medium temperature can easily cause failure and leakage of dynamic seals, leading to fire, and also cause misalignment between the motor and pump in the stainless steel oil pump, resulting in vibration. In addition, high temperatures also contribute to the corrosion of metals by sulfur. Therefore, the slag oil pump needs to use a hot oil pump, install a mechanical seal, and be equipped with a cooling and cooling system. The parts for cooling and cooling include the bearings, sealing chambers, supports, and mechanical seals of the pump. There are two types of cooling media: new water and flushing sealing oil. In the management of residual oil gear pumps, the following measures can be taken to cool the cooling system.

(2) Check and adjust the drainage temperature of the cooling water to prevent overheating, in order to slow down the formation of scale and maintain the heat transfer and cooling efficiency of the cooling system. When the cooling water is not unobstructed and the outlet water temperature is high, the cooling water system should be cleaned or chemically cleaned in a timely manner. Use a metal descaling agent with no corrosive effect on the cooling system metal during chemical cleaning. Chemical cleaning can be used to clean the cooling system for a short period of time without disassembling the pump.

(3) Choose high initial boiling point oil products as sealing oil, reduce the temperature of mechanical seal flushing and cooling sealing oil, and increase the injection pressure and flow rate of cooling sealing oil. Generally, the sealing oil is supplied by the side line oil of the vacuum tower in this device. Considering abnormal operation, partial side lines without oil during operation, or the use of external sealing oil during start-up, multiple side lines are usually used to provide sealing oil. Therefore, when conditions permit, using oil with low profile and high initial boiling point as sealing oil can prevent sealing oil from entering the residual oil gear pump and causing heating and vaporization, resulting in suction failure. At the same time as providing sealing oil on the side line, the side line itself, as a product of the distillation unit, also needs to be adjusted. Therefore, stable sealing oil is required at the same time as the side line product.

The assembly process of the thermal oil pump needs to be carried out step by step according to the process requirements, and rough operation directly affects the product of the thermal oil pump. Heat transfer oil pumps are divided into cast steel type heat transfer oil pumps and stainless steel type heat transfer oil pumps, as well as vertical heat transfer oil pumps, and their assembly sequence is roughly the same. The specific steps are as follows: 1. Go to the accessory warehouse to collect all the necessary accessories for assembling the thermal oil pump.

2、 Heat up the cleaning machine and clean all the impeller, bearing sleeve, pump body, pump cover, pressure cover, and shaft of the thermal oil pump.

3、 Take out the heat transfer oil pump accessories from the cleaning machine and wipe them clean with clean cotton yarn in order. Place them on the pump loading console and prepare for assembly.

4、 Install the pump coupling on the head section of the pump shaft of the thermal oil pump.

5、 Press the seal of the thermal oil pump shaft head into the sealing gland of the thermal oil pump, and install it on the pump shaft from the other end of the pump shaft.

6、 Insert the snap ring along the locking nut end of the shaft onto the pump shaft and secure it in the groove of the snap ring behind the sealing cover. Then, pour grease onto the bearing body of the pump and align the bearing position with the bearing body position. Use a copper rod to insert the bearing into the bearing position of the bearing body next to the pump coupling. Do not apply too much force to avoid damaging the bearings.

7、 Insert the spindle into the bearing body from the inside of the bearing and tighten the sealing cover onto the bearing body.

8、 Install the bearing body from the other end of the spindle into the disc bearing, using the same method as the six items.

9、 Insert the snap ring along the shaft and clamp it in the snap ring groove next to the bearing, and add a retaining ring.

10、 Seal the high-temperature carbon fiber packing of the pre prepared thermal oil pump soaked in oil into the bearing body, and compact it with a sleeve.

11、 Install the heat transfer oil pump body onto the pump bearing body, install the skeleton oil seal of the heat transfer oil pump along the shaft into the heat transfer oil pump cover, and press the retaining ring and locking nut.

12、 Install the impeller of the thermal oil pump and tighten the locking nut.

13、 Place the sealing aluminum gasket of the thermal oil pump body into the pump body, install the coaxial bearing body of the pump cover of the thermal oil pump vertically into the pump body, and tighten the bolts.

14、 The entire thermal oil pump has been assembled.

Secondly, gear oil pump pipeline technology

Pipeline refers to various measures taken to restore and change the condition of the pipeline, extend the service life of the gear pump pipeline, and restore the original designed conveying function of the pipeline when the pipeline condition deteriorates on a large scale and cannot operate normally. With the development of modern petroleum industry and technological progress, various new and revised methods have emerged in the past two decades. Modern correction methods usually do not require lifting the pipeline out of the trench and can be cleaned in place. Some methods can also be carried out without stopping the pipeline. The correction methods for pipelines with different conveying media are also different. For example, fiberglass outer coating is mainly used for crude oil pipelines: on-site double-layer winding tape method for new and old coatings is mainly used for online high-pressure gas pipelines. For pipelines with localized corrosion and leakage, techniques such as epoxy sleeve method, clamp method, and sealing method are adopted under the condition of continuous pipeline transportation. In the past decade, various lining methods have been used inside the pipeline to in-situ treat the original pipeline. The core of this technology is the lining material and construction process. The commonly used lining materials include liquid or powder coating lining, cement mortar lining, flexible hose lining, hard plastic pipe sleeve lining, and fiberglass lining.

The integrity and integrity of the gear oil pump pipeline largely depend on the technical and economic characteristics of the structural materials used, so the requirements for structural materials are particularly high. Its basic requirements are: good adhesion to metals, good electrical insulation, electrical and chemical stability (corrosion resistance) and heat resistance, high mechanical strength and toughness (such as hydrogen embrittlement resistance, corrosion cracking performance, etc.), and easy construction. Starting from practical needs, one of the important principles of the new era is to minimize pipeline shutdown time as much as possible, in order to ultimately achieve uninterrupted transmission. This is a major challenge that practical engineering presents to technology. From the perspective of application, there is a trend towards using internal technologies to simultaneously solve the problem of inner and outer layer failure. For example, the use of plastic pipe insertion method can simultaneously play the role of both inner and outer layers. Using the original metal pipe as a protective shell, it seems that various excavation free internal insertion lining technologies will be one of the directions for the development of pipeline technology in the future.