10+ Derwaza Contracting Interview Questions and Answers

I have experience working with multiple pump and blower companies, including but not limited to Sulzer, Flowserve, and Gardner Denver.

• I have worked with Sulzer pumps in a chemical plant setting

• I have experience maintaining Flowserve pumps in a power plant

• I have repaired Gardner Denver blowers in a manufacturing facility

• I am familiar with other brands such as Ingersoll Rand and Atlas Copco

A mechanical seal typically consists of two main parts: the stationary part and the rotating part.

• Mechanical seals can have various designs and configurations, but most commonly they have two parts.

• The stationary part is usually attached to the pump housing or casing, while the rotating part is attached to the pump shaft.

• The two parts come together to form a seal that prevents fluid from leaking out of the pump.

• Some mechanical seals may have additional parts, such as springs ...read more

There are several types of pumps used in various industries for different purposes.

• Centrifugal pumps

• Reciprocating pumps

• Rotary pumps

• Diaphragm pumps

• Gear pumps

• Peristaltic pumps

• Piston pumps

• Jet pumps

• Submersible pumps

• Vacuum pumps

Alignment is the process of adjusting the position of two or more components to ensure they are in the correct position and orientation.

• Alignment is critical for ensuring proper functioning of machinery and equipment.

• Common methods of alignment include laser alignment, dial indicator alignment, and straight edge alignment.

• Alignment should be performed regularly to prevent wear and tear on components and reduce the risk of breakdowns.

• Examples of components that require alignme...read more

Work permit is a document that authorizes a person to carry out a specific job or task.

• Work permit is required for tasks that involve high risk or require specialized skills.

• It outlines the scope of work, safety precautions, and duration of the job.

• It is issued by the employer or a designated authority.

• Examples include hot work permit, confined space entry permit, and electrical work permit.

Couplings are used to connect two shafts together for transmitting power. There are various types of couplings.

• Rigid Coupling

• Flexible Coupling

• Universal Coupling

• Jaw Coupling

• Gear Coupling

• Disc Coupling

• Chain Coupling

• Oldham Coupling

• Fluid Coupling

Bearings are used to reduce friction between two moving parts. There are several types of bearings.

• Ball bearings

• Roller bearings

• Needle bearings

• Thrust bearings

• Sleeve bearings

• Tapered roller bearings

Water and wastewater flow schemes are the systems used to manage the flow of water and wastewater in treatment plants and distribution networks.

• Water flow schemes involve the treatment of raw water to make it safe for consumption and distribution to consumers.

• Wastewater flow schemes involve the collection, treatment, and disposal of wastewater to prevent environmental pollution.

• Water flow schemes typically include processes such as coagulation, sedimentation, filtration, and ...read more

Dosing is a crucial process in RO, ETP, CIP, and Ion exchange systems to maintain optimal performance.

• Dosing involves adding chemicals to the system to improve efficiency and remove impurities.

• RO systems require dosing of antiscalants and biocides to prevent scaling and bacterial growth.

• ETP systems require dosing of coagulants, flocculants, and pH adjusters to remove pollutants and balance pH levels.

• CIP systems require dosing of detergents and sanitizers to clean and disinfec...read more