Explain about surface preparation, Mechanical Engineering

Assignment Help:

Q. Explain about Surface Preparation?

All oil, grease, salts, and any other contaminants detrimental to the formation of a good coating bond or coating quality must be removed prior to the coating operation. Prior to blast cleaning the pipe shall be preheated to remove moisture. The pipe temperature shall be maintained at a temperature at least 5°F (3°C) above the dew point, but less than 300°F (150°C), during blast cleaning and inspection.

Suitable provisional caps shall be applied into both pipe ends in order to prevent abrasive and coating material from entering into the pipe. Care shall be taken to avoid damage to weld bevels and steel surfaces.

The blast cleaned surface shall be visually inspected for defects which would impair proper coating application. Defects shall be removed by grinding or hand filing. If defect removal is not possible, the joint shall be set aside for OWNER's inspection. The surface profile, measured from peak to trough, shall be 1.6 to 3.9 mils (40 to 100 μm), inclusive, and in accordance with the powder manufacturer's recommendations.

Residual blast products shall be suitably removed from the pipe surface by Clean Air Wash, or by High Pressure Water Wash followed by an air blast to remove excess water on the pipe. The internal surface of the pipe shall be cleaned by vacuum or blown with compressed air to ensure that no traces of blasting media remain in the pipe. Air shall be dry and free of oil and grease contaminants.


Related Discussions:- Explain about surface preparation

Calculate the survival function and expected value, Question Suppose T ...

Question Suppose T 1 and T 2 are independent and identically distributed Exponential variables with common hazard λ. What is the density of T = T 1 + T 2 ? What is the E(T-1

Battery charger-electrical instruments , Battery Charger: As suggested by ...

Battery Charger: As suggested by the name, it is used to charge a battery. The detailed procedure for charging a battery is given in later units. List the uses of following too

Determine time required to stop the automobile, Determine time required to ...

Determine time required to stop the automobile: A 20KN automobile is moving at speed of 70Kmph when brakes are fully applied causing all the four wheels to skid. Determine ti

Mounting systems for the welding head-boom mounted type, Mounting Systems ...

Mounting Systems For The  Welding Head-Boom mounted type These are the most versatile type of welding systems. Normally the boom is supported by means of a column. The welding

Calculate the mechanical output power, A 415 V, 5 kW, 50 Hz, 4-pole, 3-phas...

A 415 V, 5 kW, 50 Hz, 4-pole, 3-phase wound-rotor induction motor has the following characteristics:  Stator winding resistance R 1 = 2.1 Ω, Referred rotor windi

Calculate the normal time for this operation, a) Describe Industrial Engine...

a) Describe Industrial Engineering. Discuss its scope and use in service and manufacturing industries. b) Deriving the stop watch study in a machine shop, ten observation of a d

Development of coated electrodes, DEVELOPMENT OF COATED ELECTRODES C...

DEVELOPMENT OF COATED ELECTRODES Can welding be done by bare wire? Why do we require coating at all? What are the different types of coating? What are the stages in

What is bolt elongation, Q. What is Bolt Elongation? The required bolt ...

Q. What is Bolt Elongation? The required bolt elongation Δ 1 may be calculated by the equation (7): Δ 1 = 3.25 * 10-8 * SB * L0 (in) (7) Where L 0 is the effect

Calculate resonant frequency, A vibrating system having mass 1.2 Kg is susp...

A vibrating system having mass 1.2 Kg is suspended by a spring of stiffness 1000 N/m and it is put to harmonic excitation of 10 N. Assuming viscous damping, Calculate : (a) R

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd