Professional Experience

Resume

Coastal Pacific Crane and Hoist Engineering LTD. 

Surrey, BC    2015 - Present

Gantry Crane  , FEA Stress Analysis

Gantry Crane 3D CAD Model 

Jib Crane 

GrandPipe Manufacturing Inc., 

Vancouver, BC    2011 – November 2014


Management

Engineering

Main projects

Designed the largest hydrostatic pressure test machine for fiberglass pipes of up to 4000mm in pipe diameter and 15m in pipe length:

Professional  experience in IRAN 

Awards and Achievements

 Projects


Designed and supervised the production of 6 Hydrotest machines that are used to carry out hydrostatic tests on GRP and steel pipes.  The last Hydrotest designed in 2010 was the largest in the world.



Contributed significantly to the establishment of Farabard Industrial Factory, oversaw the training of employees in the use of new equipment and production techniques, developed and executed efficient plans to meet production targets, corresponded directly and effectively with clients and customers.


Design consultation and supervision of the production of several GRP pipe manufacturing machines (CNC continuous Filament Winder)

Designed a new Auto Variable Hub for air cooler fans which changes blade angle while the fan is operating.

Designed long spacer-type flexible couplings that are used in cooling towers to transmit power from the motor to the gear box. Possible maximum pipe bend was determined using ANSYS software.

Created a big Universal Lathe Machine which can perform machining in a 4 meter diameter. This machine was created by applying certain changes to an old Universal Lathe Machine.

Designed and supervised the production of 2 grinder machines to make slots in GRP pipe couplings. The main shaft of the spindle drive was 1100mm in length, 100mm in diameter and 3000 RPM.

Designed and manufactured a fully pneumatic sand conveying system (Dilute Phase) with its additional devices including vibrator, bag filter, and cyclone separator.

Designed and supervised the production of several hydraulic presses.

Farassan  Group  /  Farabard Factory Manager,  Shiraz, Iran 2007 – 2010

Executive Manager   2004 – 2007

The following were implemented during my time as manager of Farabard Factory in collaboration with my engineering team

Farabard  Factory in 2007

Farabard factory in 2010 , When  I left the Factory

Farabard Factory 2010 - When I left the factory

Farabard Factory 

In 2006, the management committee members decided to establish a professional Machine Factory to design and produce Hubs, FRP Fans, and GRP Pipe Production Lines.

After 6 months of constant search, I found a 10,000 square meters land with a 1,000 square meters building in Gouyom, which is a small town near Shiraz.

Only ten employees worked in my team when the CEO bought the place. We moved in the cold season without having proper facilities. There was lots of work needed to be done and we had to overcome many problems.

The first problem was a huge 2000 tons hydraulic press which was located inside the building of the Factory. We helped the previous owner to move this giant press out of the factory.

The second step was to order a 10 tons overhead crane. We had to move all machine shops section by section in the workshop to prepare a solid foundation for the floor.

The next step was hiring new professional machinists, technicians, and welders. We also needed to buy new machine shoes  and equipment. I traveled to North of Iran where there are machine producing factories to buy new or used machines.

My team and I worked very hard to create a professional Machine Factory. After three years we accomplished the followings:


Mechanical Engineer – Fan Department   (Oil and Gas Industry)

Farassan (Farabard) - Shiraz, Iran 2000 – 2004

Drive Shaft

Long spacer-type flexible couplings are used on cooling tower applications to transmit power from the motor to the gear box and accommodate the misalignment that takes place between these two shafts during operation. These long spacer couplings require unique design and manufacturing considerations to assure proper operation on these applications. The center spacers are usually fabricated of tubular construction to minimize weight on the connected shafts and provide adequate lateral rigidity.

Designed long spacer-type flexible couplings that are used in cooling towers to transmit power from the motor to the gear box. Possible maximum pipe bend was determined using ANSYS software. 


About 400 g  balance weight 

20 g  balance weight

Max  deformation

Fig 1

Fig 2 

Fig 3

Fig 4 

Fig 5

Fig 6

Fig 7

Fig 8

Fig 9 

Fig 10

Design and Manufacturing an Auto-Variable pitch hub for air-cooled heat exchangers

B.Torabi1, B.Gharesi Fard2

 Abstract

This paper presents the design and manufacturing of an automatic hub for air-cooled heat exchangers, in presented model air pressure is used to maintain the desired blade’s angle. New AV (auto-variable) hub piston-cylinder or diaphragm actuating system has not been used as in pervious works. The actuating rods are in tension instead of compression in other usual automatic hubs, so buckling will not occur in rods. Furthermore new AV hubs permits easy, fast  and time consuming procedure for changing blade’s angle with out running air-cooled heat exchanger out of work.

 Introduction

Air would seem the best choice for coolant, instead of water, because of the fact it is around us in unlimited quantities. In our country most of petroleum and chemical industries use air-cooled units on a large scale. The successful performance of the air-cooled units encouraged engineers to consider the use of air coolant, and several works have done to have higher performance in air-cooled units. An air cooled unit consists of there basic parts; tube bundle, the structure and the mechanical drive system as shown in Fig (1). Mechanical drive system is made up of fans, transmission and drivers. The most common fan-blade materials is aluminum, but in presented work, fiberglass reinforced plastic is considered. V-belts or gear can be used as transmission parts with electrical motor as driver, but V-belts are most popular. Fan speed is set by using a proper combination of sprocket or sheave sizes with timing belts or V-belts, and by selecting a proper reduction ratio with gears. Fig (2) provided a breakdown of the mechanical equipment. Two different categories of hubs can be fitted to fan shafts, fixed and automatic pitch types; the second has several advantages, for example in temperature control. In fixed hubs as shown in Fig (3) changing fans pitch require reinstalling system. As we know, air temperature in comparison with water is subjected to greater and more rapid fluctuation, particularly as a result of sun and showers and variations in weather. Several methods can be used to control temperature in air-cooled heat exchangers. By pass, Louvers, motor control and variable-pitch fans are some of usual methods. The last is considered in this paper. In most common variable-pitch fan models the pitch of each fan may be altered manually to suit the prevailing operating conditions. In new AV hub, air pressure is used to change blade’s angle and operator only push a switch to have desired blade’s angle. Previous models as shown in Fig (5) used diaphragm and piston cylinder, so hub lubrication with synthetic lubricants should be done at least every year; it needs reassembly of the apparatus and so cause damage.   In new model simple service procedure and avoiding possibility of errors during disassembly, reassembly and start up was considered in design of different parts. 


Selecting fan pitch angle

1.    Positive pitch (thick edge of blade down) is usually determined from specifications of heat exchanger. That is related to hot air temperature on induced draft units or ambient air temperature for forced draft units. Usually draft pitch angle will be exceeded in order to use all available motor amperage.

 2. Negative pitch, is normally set to attain minimum ‘zero’ air flow. This will be about minus 13o for induced draft units or minus 8o for forced draft units. If full reverse flow is desired, the negative pitch setting will be usually -30o to -35o.

 Automatic Hub modeling

As mentioned before new AV hub changes blades pitch with changing air pressure in an air-spring. Air-spring is designed by assuming the required pressure to rotate blades.This will force the top plate to move. Then the connecting rods transform the up-down plate’s motion to cause rotation in blades housing.Auto variable hub consists of 6 main parts as shown in Fig (4).

 1. Steel structure

Hub structure is constructed from materials selected to fight corrosion to insure many years of service. Plates are made from ST37 and then epoxies.CK45 has been used for bushes and GGG45 for bearing’s housing.MO40 and hot dip galvanize steel is used and finishes carefully where needed.Then hub is fitted to fan shafts using a standard tapered bushing and place into the clamps. This structure can be used for other types of blades only with changing clamps. 

2. Taper bearing, housing and bushes

Taper bearings are designed after obtaining drag and lift forces in blades from their drag and lift curves. Then by considering induced centrifugal forces, appropriate SKF taper bearings with reliability 0.9994 and safety factor 2.31 selected. 

3. An air-spring to pressurize the moving plate

Air-spring is the main part in rotating procedure. This instrument consists of a tube part and two caps as shown in Fig (6) and should maintain the required force for moving top plate and also it should be appropriate vibration isolator and maintain the required stroke. The instrument has been provided from a German company; it is from WBE 400 series and can handle internal pressure up to 10 bars. 

4. Springs

The function of the spring is to overcome the pressure instrument which tries to feather the blade. The designed spring has 1 mm space between coils in compression mode and 8 effective coils. Because of the distinguish pressure lines available in different petroleum industries the instrument should be able to adjust with line pressure. This can be achieved in new model, since its spring permitted to be changed easily if needed. This spring is shown in Fig (7).

 5. Connecting rods and joints.

As mentioned before one of the advantages of new AV model is that rods should maintain tension instead of compression force, so no buckling will occur in rods. Connecting rods and their joints designed manually and by Ansys software to ensure the required safety factor.

 6. Central Tapered Bush

This part of instrument’s duty as shown in Fig (8) is to connect hub with transmission part. Because of taper shape of this bush its installation is easy and no heat processing is required.

 Results

The assembled model performance has been tested in working model 3D software. It is shown in Fig (10). Clamp rotation is plotted against time in Fig (9) and it shows that the apparatus can rotate the blades up to 44 degrees and the practical experiments on the instrument verify this results. This project’s primary design and research takes 4 months and about 6 months for manufacturing different parts, assembly and providing air-spring device. New Instrument has been tested in Bandar Amam petroleum industry and shows great performance.

  Conclusions

A new automatic hub for variable-pitch fans presented here. New model has several advantages in comparison with its similar models, like easy and clean mounting and lighter weight.

In the design point of view using tension mechanism instead of compression ones used in other models, permitted higher safety. No diaphragm and piston cylinder mechanism used so the offered mechanism is cost consuming and has simple inspection and service procedure.

We believe that this mechanism is suitable for automatic temperature control approach, because it works with pressure, so fully automatic air-cooled heat exchanger may be achieved by using these AV hubs.

References

1. Heat exchangers ‘Selection, Design and construction’, E.A.D Sanders.

2.   Heat exchanger Design, M.Kahrom, 1370.

3.   Hudson Company, Hub and Fan Standards.

 


Material handling