Industrial Maintenance Solutions

Mechanical seals are critical components of pumps, responsible for maintaining a fluid-tight seal between the rotating shaft and the stationary pump housing. However, these seals can fail due to various factors, leading to leakage, reduced pump efficiency, and costly downtime. In this article, we will discuss the top reasons for mechanical seal failure in pumps and how to prevent them. 1-Improper Seal Selection Choosing the wrong mechanical seal can cause it to fail. Consider the following factors that can contribute to seal failure: • Chemical compatibility: All seal components, such as the seal faces and O-rings, must be compatible not only with the process fluid being pumped, but also with non-process fluids used for cleaning, steam, acid, and caustic flushes, etc. • Physical degradation: Using soft seal faces on abrasive liquids will not last. Shear-sensitive liquids, like chocolate, can break down and leave behind solids (such as cocoa powder) and force out liquids (like oil). • S...

Intermittent motion compressors, or non-continuous flow compressors, include screw compressors which are categorized as medium flow and medium pressure compressors when compared to other compressor types based on pressure/flow charts. The screw compressor gets its name from the two screws it contains, one of which is mounted with the prime mover (motor, turbine) and the other is driven. The screws are mounted together by gears and rotate in opposite directions to each other, squeezing the compressed air with oil in the compression zone to raise its pressure according to the direction of rotation of the driver (counter-clockwise). During operation, the compressed air is mixed with oil (flooded type) inside the compressor. The compressed oil and air are then separated in an oil separation unit, with the air being removed to the discharge line and the oil being returned to the oil filter for filtration before being returned to the suction of the compressor. This compressor type is kno...

Submersible pumps are commonly used in various industries such as construction, mining, wastewater treatment, agriculture, and general manufacturing. Typically, these pumps consist of a vertical electric drive motor that is directly connected to the impeller, and they are designed to operate for long periods with minimal maintenance. BEARING ARRANGEMENT The bottom bearing, also known as the locating bearing, usually consists of a double-row angular contact ball bearing or a pair of angular contact bearings, which are responsible for supporting the axial and radial loads generated by the pumped fluid. Since the bearing is subjected to heavy loads, it is important to select the appropriate bearing to achieve the desired service life. On the other hand, the top free bearing is generally a deep groove ball bearing that takes a light radial load. Typically, C3 clearance is used to compensate for the reduction in clearance caused by the heat generated by the electric motor. CREEP PHENOME...

By NTS Pump shaft failure can lead to significant downtime and repair costs in industrial plants. One of the most common locations for pump shaft failure is at the keyway area. In this article, we will explore the reasons why pump shafts often break at the keyway and what can be done to prevent such failures. The keyway is a high-stress point (weakest point)  on the shaft, where a key is inserted to transmit torque between the shaft and the pump impeller or coupling. During operation, the keyway experiences cyclic loading that creates a bending moment in the shaft, which is concentrated in the keyway area. Over time, this cyclic loading can cause fatigue failure in the shaft material, leading to a fracture at the keyway. In addition to cyclic loading, other factors can contribute to shaft failure at the keyway. Improper keyway design or installation can lead to stress concentrations or inadequate clearance between the key and keyway . Misalignment or overloading can also cause ex...

By NTS Pump shaft breakage is a common issue that can cause costly downtime and repairs in various industries. In this article, we will explore several case studies of pump shaft breakage and the solutions implemented to prevent future failures. Case Study 1: Chemical Processing Plant A chemical processing plant experienced repeated pump shaft breakages in their cooling water pumps. Investigation revealed that the pumps were not properly aligned with the motor and had excessive vibration due to the misalignment. This caused the pump shaft to fatigue and break over time. The problem was resolved by realigning the pumps and installing vibration monitoring equipment to detect any future misalignment or excessive vibration. Case Study 2: Wastewater Treatment Plant A wastewater treatment plant had issues with pump shaft breakage in their sludge pumps. The pumps were designed with a straight shaft and lacked a flexible coupling, causing excessive stress and vibration on the pump sha...

Machinery that operates at speeds below 600 rpm falls under the category of low-speed machines. These machines are typically large and possess high rotating inertias, making them crucial components of the production line. Although these machines are less prone to breakdowns, they are considered critical, and their failure can result in enormous production losses, significant downtime, and substantial replacement costs. Historically, there has been limited interest in the condition monitoring of these machines due to their infrequent failures. The parts of these machines that necessitate condition monitoring are primarily the bearings and gears in motion. This article will cover modern and innovative techniques for monitoring the condition of low-speed machinery, with a particular emphasis on monitoring the condition of rolling element bearings. Monitoring low-speed bearings present unique challenges. In the case of high-speed bearings, vibration analysis, thermography, and wear deb...

By NTS. Pump shafts are essential in many industrial and commercial applications, providing the necessary mechanical force to move fluids through pipelines and process systems. However, when a pump shaft breaks, it can cause significant downtime, production losses, and safety risks. In this article, we will explore the common causes of pump shaft breakage and how to prevent it from occurring. 1. Excessive Load  The most common cause of pump shaft breakage is excessive load. When a pump is overloaded, it places a significant amount of stress on the shaft, causing it to bend, warp, or break. Overloading can be caused by a variety of factors such as a clogged discharge line, worn impeller, or damaged bearings. Proper maintenance, regular inspections, and monitoring of the pump's performance can help prevent overloading. 2. Misalignment  If the pump and motor are not properly aligned, it can cause stress on the pump shaft and lead to breakage. Misalignment can occur due ...

Electric motors are the workhorses of modern industry, powering everything from pumps and fans to conveyor belts and heavy machinery. But these vital components are not immune to wear and tear, and one common problem that can lead to premature motor failure is bearing damage caused by shaft current. Shaft current is a type of electrical discharge that occurs when there is a voltage potential between the motor shaft and the bearing, resulting in the flow of electrical current through the bearing. This current can cause a range of problems, including pitting and fluting of the bearing surfaces, which can lead to premature wear and failure. Shaft current Motor shaft current can have several harmful effects on bearings, including: 1.      Bearing pitting and fluting: Electrical discharges can cause tiny pits and flutes to form on the bearing surfaces, leading to premature wear and failure. 2.       Bearing noise and vibration: Shaft current can cause ...