Training course dox

This training course is aiming to introduce Gastec to any entry level engineer. In order to

develop his knowledge about the company’s field as quick as possible. Not only in his specialty but

about Gastec’s CNG field as whole

Egyptian International Gas Technology Co. GASTEC

Maintenance Department

2

Acknowledgements

First I should thank Allah that gave me this kind of opportunity to learn all what I’ve learned through my training period in GASTEC

I am grateful for my entire supervisor Eng. / Ayman Ramzy and Eng. /Reda Ahmed for their assistance and support in order to finish this training course

I would like to thank every Engineer and technician who taught, showed or explained a single detail about anything in the company’s Field

Special thank to Eng. Mohamed saad & Eng. Amro Hassan for their mechanical support. Also to my colleges who shared with me their knowledge about every single detail in our work.

Special thank to Eng. Mohamed Koutb for his detailed assistance to me in all the electrical devices’ troubleshooting. Also how understanding and tracing any troubleshooting.



3

1. Introduction

1.1 Gastec:

It is a company that works in the field of the CNG “compressed natural gas”. It works on supplying the cars

with natural gas on 220 bars. It takes the natural gas the network at medium pressure to convert it into

high pressure gas that is suitable to be reserved in a cylindrical tank in the car. Not only it supply the gas

but also it assembly the conversion kit and plug it to the cars.

Gastec considered being the Pioneer of using the natural gas as cars’ fuel. It has now over 42 stations all

over Egypt with a plan for expansion every year.

1.2 Natural gas:

Natural gas is a mixture of hydrocarbon volatile gasses, Methane is the CH4 and its percentage varies from

80% to 96%. This percentage varies from a field to another. In addition to another components

Ethane 4%

propane 0.03%

Butane Negligible percentage

Nitrogen Negligible percentage

CO2 Negligible Percentage

Thereby Methane is the most effective in methane properties in the natural gas. That is why they call the

natural gas Methane

There are to main types of gasses that have been used CNG “Compressed natural gas” LPG “Liquefied

petroleum gas”. In cars we use CNG which is withdrawn from the network at 2.5 bar and charge the cars

with 220 bar, while in home use there are the cylinders that contains LPG which are a mixture of

compressed petrol, with mainly propane and butane gas as main component .



4

1.3 Natural gases Properties and Calorific value compared

to benzene

Fuel type Density (Kg/m3) Calorific value (MJ/Kg)

CNG 0.73 48

benzene 720-780 43

Diesel 820-950 42

1.4 Natural gas mining:

1st method:

You harvest the gas alone without any accompanied oils and that called Gas Well, and it is the main

method of gas mining.

2nd method:

You harvest the gas with petroleum oil, and that gas is produced because of the high temperature and

pressure inside the earth’s layers. And that gas is called associated gas.

1.5 Natural gas properties:

1. The natural gas has a property of being less dense that the air. Its’ density is 0.73 kg/m3 under sever

condition which is 1 Bar and temperature 15 Degree, that leads to its escape to the higher level of the

earth’s atmosphere. That minimizes its ignition probability.

2. The natural gas doesn’t ignite except under high concentration percentages with high temperature level



5

2. Station Main components

1. Mechanical Equipments

2. Electrical & control Equipments

3. Piping and instrumentation

2.1 Electrical & Control Equipments

2.1.1 Driver

There are two types of drivers in use:

2.1.1.1 Internal combustion engine, a caterpillar six cylinder gas engine is used in Haya’a

station.

2.1.1.2 Electrical induction motor, there is many companies produce the induction motors

starting from ABB, Siemens and Baldor, we use the induction motor for its wide torque

speed characteristics. Their power range for the driver we use from 150 Hp to 300 Hp

How to order a Driver

When you are going to select a drive there are two perspectives you should consider firstly the electrical

perspectives then the mechanical specifications

Electrical specifications:

Efficiency of the motor, HP range, Frame Size, Frequency, Power, Voltage, service factor

(sine wave) “i.e. 1.15”, electrical design “i.e. NEMA – design X”, stator winding copper

winding, insulation “i.e. Class F, meets NEMA MG1 – 2003 Part 30”, Temperature rise (sine

wave) “i.e. class B @ 1.0 SF ”

Mechanical specification:

Frame’s material, Conduit Box, lead seal gasket “Neoprene”, Cooling fan “140-440

Bidirectional, polypropylene 5440 locked & keyed bronze”, bearing type “single shielded*”,

rotors material “Die cast Aluminum”,



6



7

2.1.2 Main Electrical panel

It consists of Main circuit breaker in the range of 630 A. there is a phase sequencer because some time

after the electrical cut the three phase sequence return in a reverse phase order so the phase sequencer

trip the circuit breaker, there is also a manual breaker with two ways to connect in order to over come

this event. This panel had fully designed and stated its own

specification by Eng Moneer Elnawawy

2.1.2.1 Circuit breaker:

Mainly we deal with Marlin Gerain or Cutler

Hammer, but there are other types that are

in use. There are shunt trip terminals that

are connected to the phase sequencer to cut

the circuit of in case of any up normal

condition. Also on its inputs there a current

transformer to transmit the value of the

current to the phase sequencer as we see in

the picture

How to perform the setting of the circuit breaker*

You calculate the current that is going to be

with drowning by the equipments. Then

2.1.2.2 Phase sequencer

Its name is usually SAMMO EOCD “3DI, 3DF, 3DS, 3DM” this

kind of series are analog which have dip switch for settings

while 3DE is the digital series, its main sittings nominal current,

O.t “Starting current”, D.t “delay time of fault”, Phase reverse

“-RP-”, PL “Phase lose”, Ub “unbalance”, locked rotor

protection Alarms, there are types that display a relative

current according to the transformation ratio of the

transformer



8

I.e. if the transformation ratio is 600/5=120 and the displayed current is 2 that means

that the actual value is 240 A, there another types that display the actual value

Specification could be known from the model

i.e. EOCR – 3DI 05 440

3DI digital inverse time type multifunctional current relay

05 is the current adjustments which indicate that it have current from 0.5 to 5

A while it could be 60 that indicates current from 1.6 to 8.6 A

440 is the operating voltage that is within range 180 to 480 V, also it could be

20 that indicates working voltage within range 90 to 260 volt.

Event:

There was a repetitive fault that happen in Helwan station they all thought it is

overload at first but when Koutb went there he discovered that the fault was not an

over load fault it was unbalance fault since the air compressor was taken from the

compressor contactor and it take about 15 A and since the permitted range of the

unbalance is 20 A he set a new setting with phase unbalance 35 A and the job is done

2.1.2.3 Manual Breaker with 2 ways to connect, this breaker is used to switch the phases since

there is some time when a cut off occur and there is a recovery in the line the phase

sequence is reversed, in order to shame this reverse we use this breaker

Supply

220 or 380 Shunt trip



9

Event:

While we were making a run test on the motors of Manar station, we found that the

motors rotates anti clock wise so we reversed this hand in order to restore the right

rotation, but if not all the motors were the same , we should have reversed the phases

of the reversed motor. Take care also that it is not a must to have the rotation clock

wise or anti clock wise it is according to the flow and the fan angle

2.1.2.4 ESD “Emergency Shut Down” this a normally close switches that

exist in the circuit to shut the circuit down in case of any up

normal condition by cutting both of the AC “110” and DC “24”

from all the circuit, since it is a normally close switches so when

we are connecting more than one switch, we connect them in

series. While in case of normally open switches “i.e. starts push

button” we connect them in parallel. The data sheet of this model

you will find it in the appendix.

Event:

While I was in MANAR site there was an ESD push button that is

normally close and due to the glass is normally pushing it will stay

open, Mohamed salah the technician said to me that we will

connect it on the normally open sitting and due to the glass it

always closed in case of emergency anyone will break the glass

and the push button will be released opening the circuit.

2.1.2.5 Power factor corrector panel is a panel

consists of sets of capacitor banks that log

as sets to correct the power factor in order

to reach unity to reduce the consumption of

reactive power. It consists of 8 capacitor

sets (fuses 50 A strike, power factor

regulator, and FRAKO 20 KVAR capacitors).

Event:

At kalub station there were some sits of the capacitor

banks broke down, also there were some sets had there fuses broke down

so they replaced the fuses and the system restore its state “you could know that the

fuse is broken down from an indicator like a paper in the top of it”



10

2.1.3 Auxiliary panel

2.1.3.1 Main motor contactor

2.1.3.2 Power supply

The controls’ systems don’t work with

alternating currents, also due to that most

of our systems are American, which work

on 110 VAC. While for the control circuit

you need 24 VDC. So you need a power

supply to supply both of those circuits.



11

2.1.3.3 Insertion module

When the compressor fall down for a certain Emergency stop and we need to operate

it once more we use this button in order to force it to start.

2.1.3.4 Barriers

They are used as buffers between the sensors in the hazard area and the PLC as a

protection for PLC at mean while it reduce the current used by those sensors in order

to avoid formation of the spark inside the hazard areas.

2.1.3.5 Gas detectors.

Those modules are used to detect the gas leakage

in case of closed areas or enclosures.

2.1.3.6 Auxiliary motors contactors the are the contactors

that is responsible for the operation of the auxiliary

motors such as water pump, oil pump, air



12

compressor and air extractor “in case of enclosure” ………etc.

2.1.3.7 Auxiliary motors thermal protection it is a kind of protection to each motor.

Event: “Helwan station”

In case there is a fault in a certain motor of these motors you will find the thermal

contactor turned on off position, they reported auxiliary motor run fault and before

Eng. Koutb reaches the station the make a reset that made him not able to identify

which motor that made the fault

2.1.3.8 Inverters “vacon frequency inverter”. It consists of two main unit units’ power and

control unit. It is three phase AC choke(1) at the main end together with the DC-link

capacitor (2) form an LC-filter, together with the diode bridge “half wave rectifier”

produce the DC-voltage supply to the IGBT inverter bridge (3) block. The AC-choke also

functions as a filter against high frequency disturbances from the mains as well as

against those caused by the converter to the mains. In addition to enhances the

waveform of the input current to the frequency converter. The entire power drawn by

the frequency converter from the mains is active power; the IGBT inverter bridge

produces a symmetrical, 3-phase PWM- modulated AC-voltage to the motor.



13

High overload: Max current Is, 2 sec/20 sec, 150% overload ability, 1 min/10 min following

continuous operation at rated output current, 150% rated output current for 1 min, followed by

a period of load current less than rated current, and of such duration that the r.m.s output

current, over the duty cycle, doesn’t exceed rated output current

Low overload : Max current Is, 2 sec/20 sec, 110% overload ability, 1 min/10 min following

continuous operation at rated output current, 110% rated output current for 1 min, followed by

Frequency converter type

load ability Motor Shaft power

Low high 380V supply 500V supply

Rated Continuous current IL

(A)

10% Overload current

(A)

Rated Continuous current IH

(A)

50% Overload current

(A)

Max. Current

Is (A)

10% Overload

40⁰C P(KW)

50% Overload

50⁰C P(KW)

10% Overload

40⁰C P(KW)

50% Overload

50⁰C P(KW)

NX 0590 590 649 520 780 936 315 250 400 355

NX 0520 520 572 460 690 828 250 250 355 315



14

a period of load current less than rated current, and of such duration that the r.m.s output

current, over the duty cycle, doesn’t exceed rated output current

Break resistor ratings

Converter Type Max. brake Current Resistor nom. (Ohm)

NX 590 855 0.9

NX520 570 1.4

Control characteristics

Control method:

Frequency control V/F

Open loop sensor less vector control

Closed loop vector control (NXP only)

Switching frequency

From 1 to 6 KHz : def: 3.6 KHz

Control connections

Analog input voltage:

0..10V, R=200KΩ

Analog input current

0(4)…20mA, R=250 KΩ

Analog output

0(4)...20mA, RL =500 Ω

2.1.3.9 Star-delta starters , usually we start induction motors as star connected then change it

to delta connected, That is due to the low withdrawn current in star connection with

respect to that of the delta connection, this scheme is usually used in weather ford and

JW systems

2.1.3.10 Soft starters* like those Siemens soft starters that exist in the safe’s SW old systems

they are inverters that starts the circuit and after that they make internal bypass

2.1.3.11 Lighting arrestors are usually used even though Egypt doesn’t considered to be a

country that have a weather that have probability of lighting surges a lot , this lighting



15

arrestors should be placed higher that the highest construction in the station and it is

connected to the earth electrode

Important concepts:

1. Earth it is smallest resistance in the field and it is maintained by digging a hole in the field with

electrode and coal around it in order to minimize the resistance as much as possible. Usually it

defined in manuals as an equipotential collector and it is assigned with PE symbol. and this

2. Neutral is the line that is assigned with the alternating current generation where the unbalance is

dissipated in it “Zero current”.

3. Ground is another name for the neutral.

4. Types and sizes of cable are as follows 35, 50, 70, 95, 120, 150, 185, 240, 300mm there are some

types of cables that contains the three phases with each other at the same cables and the ground

terminal that is usually half the area of one phase, Other method to act as an equivalent method is

to have a cable or more for each phase and a ground with area approximately half of one phase.

5. There is another categorization for cables. There are solid cables and strands. We usually use

stranded wires for more flexibility

6. Loading factor is a ratio between the current and the area passing in it, selecting this loading factor

depends on many parameters such as heating and transmission medium, we usually use it 2 A for

every 1 mm²

7. Main concept of starting:

o Direct-on-line (DOL) starters

With this type of starter, the stator windings of the motor

are connected directly to the three phase mains supply.

The motor starts and accelerates in a way determined by

its own characteristics. Typically, the peak starting current

is between 5 and 8 times normal full-load current, and the

peak starting torque is between 0.5 and 1.5 times the

motors nominal operating torque.



16

Although DOL starters offer a number of advantages, including simplicity, low cost and high starting torque,

their use is limited to applications where:

Low-power motors are being used, and the supply capacity is high, so that the starting current

surge does not adversely affect other equipment using the same supply

The equipment driven by the motor is fitted with a gearbox or some other device which will soften

the mechanical shock produced by the high starting torque

A high starting torque is needed - for example, the equipment starts against its full mechanical

load.

When the limitations of DOL starting are not acceptable, it is necessary to use alternative starting

techniques which reduce the peak starting current and, therefore, the peak starting torque. The normal

approach is to arrange for the motor to be started at reduced voltages, and a number of methods have

been developed for doing this

DOL starting are not suitable when:

The peak starting current would result in a

serious voltage drop on the supply system.

The equipment being driven cannot tolerate

the effects of very high peak torque loadings

The safety or comfort of those using the

equipment may be compromised by sudden

starting as, for example, with escalators and

lifts



17

o Star-delta starters

This type of starter may only be used where access is possible to both ends of all three stator windings.

In addition, the windings must be rated to withstand the full supply voltage when delta-connected. With

star delta starting, the peak starting current is typically between 1.5 and 2.6 times the normal full-load

current, and the peak starting torque is between 0.2 and 0.5 times the motor's nominal operating

torque.

On starting, the supply is first applied to the motor with its stator windings star-connected. As the motor

accelerates, its speed stabilizes when its developed torque become equal to its load torque. This usually

happens at about 75% - 80% of nominal speed. The star contactor is then De-energized, and the delta

contactor is energized to delta connect the stator windings. Each winding is now fed with the full supply

voltage, and the motor adopts its normal operating characteristics.

The run-up time with the windings star-connected is controlled by a timer which, typically, can be

adjusted from 0 to 30 seconds. This timer is adjusted during commissioning to ensure that the star-delta

changeover occurs, as closely as possible, at the point of torque equilibrium. The transition time from

star to delta is also important, and a special timer is normally used to ensure that there is a period of

between 30ms and 50ms between the opening of the star contactor and the closing of the delta

contactor. This allows time for any switching arcs to be extinguished.

Star-delta starters are particularly suited to machines which do not present a high load torque at start-

up, or which normally start off load. It is also important to note that, during the star-to-delta transition,

a high transient current is generated. If a magnetic short-circuit protective device is to be used in the

starter, this transient must be taken into account in the selection of the device, in order to prevent

nuisance tripping.



18

Although the transient produced at the star-delta transition is very brief, the current can be quite large

and, particularly for larger motors, some form of current limiting may be necessary. One solution is to

introduce a delay of 1 to 2 seconds during the star to delta transition. To avoid too large a speed drop

during the transition, however, this method can only be used

with low-inertia loads.

o Electronic soft starters

This relatively recently introduced form of starter is rapidly

growing in popularity. Soft starters operate by gradually

increasing the voltage applied to the motor, so as to produce

steady, smooth acceleration. This technique eliminates

sudden changes in voltage which could produce peaks in

both starting current and torque.

The steadily increasing supply voltage for the motor during

starting is produced by a thyristor bridge which, in each

phase, has two thyristors connected back-to back. By varying

the firing angle of each set of thyristors, it is possible to

control the starting voltage and, hence, the starting current.

Note that, unlike inverter drives, soft starters do not vary the

frequency of the supply to the motor. The detailed design of

soft starters varies from manufacturer to manufacturer,

Control of the acceleration and deceleration ramps of the

motor in such a way as to keep within all required limits on

current and torque

Thermal overload protection for itself, and for the motor which

it is controlling

Mechanical protection for the machine being driven, by eliminating sudden changes in current -

and, therefore, torque - during starting and stopping.

The peak starting current may be adjusted between 2 and 5 times nominal full-load current,

corresponding to a range of starting torques from 0.1 to 0.7 times the starting torque which would

be produced if the motor were started with a DOL starter.

o Speed regulation of asynchronous motors



19

While speed regulation, strictly, goes a little beyond motor starting, the two subjects are so closely

related that a brief discussion of speed regulation is included here for the sake of completeness.

For many years, the scope for varying the running speed of asynchronous motors was rather

restricted. Only motors with pole-changing facilities, and those with separate windings, were

popular for applications requiring multi-speed operation, but even these types could only operate at

one of a number of fixed speeds. This situation changed dramatically with the introduction of

frequency inverters which allow the running speeds of standard motors to be accurately controlled

over a wide range. Inverter technology is so successful that AC inverter drives are now being

adopted for many applications where, in the past, only DC machines, with their inherent ease of

speed control, would have been suitable.

While various methods of speed control are possible, which use only conventional components

such as contactors and resistors, these methods are fast becoming obsolete as they are replaced

by inverter systems this supplement will, therefore, deal principally with speed control by inverter?

o The frequency inverter drive

This type of drive is intended mainly for use with three-

phase squirrel cage motors. It operates by using a

technique called pulse-width modulation (PWM) to

synthesize a sinusoidal waveform, the frequency of

which can be varied, that is used to supply the motor. By

varying the frequency of the supply to the motor, the step

less motor speed variation is possible over a wide range.

Since the synthesized supply waveform is very close to sinusoidal, smooth motor rotation is

achieved even at low speeds.

o Inverter drive operation

The AC supply (single or three phases) to the inverter is rectified by a full-wave diode bridge, and

is used to charge the main reservoir capacitors.

This provides the system with a high-voltage DC source which is then switched by the output

power bridge to produce a pulse train made up of precisely controlled long and short pulses. The

train of pulses produces a sinusoidal current in the motor, the voltage and frequency of

Variable speed “soft-starting” Star-delta Direct-on-line



20

1.8 In for 200 ms Adjustable, 2 In

to 5 In

1.3 to 2.6 In 4 to 8 In Peak starting

Current

1.7 Tn Adjustable, 0.1 to

0.7 Tn

0.2 to 0.5 Tn 0.6 to 1.5 Tn Peak starting

Toque

Variable Gradual On or off On or off Control

• Parameters are

fully adjusted

during

commissioning

• Compact

• Solid state

• Easily adapted to

the application

• Infinitely variable

speed

• In-built motor

protection

• Low starting

current

• Parameters are

fully adjusted

during

commissioning

• Compact

• Solid state

• Easily adapted

to

the application

• Simple,

economic

starter

• Good starting

torque/current

performance

• Simple starter

• Low cost

• High starting

torque

Advantages

• Can cause

interference on the

supply

• Can cause

interference on

the

• Low starting

torque

• Non-adjustable

• Very high

starting

current and

Disadvantages



21

• Relatively

expensive

compared to

direct-on-line

supply during

starting and

stopping

starting

parameters

• Break in

supply to

motor leads to

severe transient

peak current

torque

• Supply must

withstand peak

current

• Mechanically

harsh

starting

sequence

0.1 to 999 seconds Adjustable, 1 to

60

seconds

3 to 7 seconds 2 to 3 seconds Run-up time

• All machines

where speed

needs to be varied

to improve

production and

reduce mechanical

wear

• Machines where

energy can be

saved by reducing

speed (centrifugal

• Machines

requiring

very smooth

starting

(centrifugal

pumps and fans,

Conveyors, etc.)

• Machines

starting

on no-load

(small

centrifugal

pumps,

Fans, etc.)

• Small

machines

may often be

started on full-

load

Typical

applications



22

This can be accurately controlled. By retaining the correct voltage/frequency ratio in the

Supply to the motor, its torque can be maintained over a wide speed range.

What is IP protection?*

Tracing in the power circuit

Hypothetically you are the electrical current, first you will pass through set of fuses with range around 500

A. afterwards there is a main cross way. One of them leads through a soft starter to the motor. While the

second leads to the power supply on the auxiliary panel that distribute it to the auxiliary motors and the

PLC power supply “24 VDC”.

How to read an electrical manual?

*

2.2 Mechanical Equipments

We will discuss the mechanical component from the packagers’ point of view. Mainly they are two main

types horizontal reciprocating “J.W., W.F., Kraus” and radial reciprocating “Safe”. Also there are many

categorization from the suction point of view there is some station that works on suction from 2-4 that

called low suction station, there some that works on suction from 4-6 that are called medium suction

station while there are some station that works on suction from 24-30 that are called high suction

stations.

Hint:

According to the European standards “Safe” the number that indicates the power of the driver is in Kilo

watt whether the American standards are in Horse power.

Safe compressors

There are 3 main types of safe compressors:

Pumps, fans, etc.)



23

1. The SW series i.e. SW200F6-EM-1/6. Which means 200 KW, suction 6 bars; Electrical motor, 1/6 is

the stroke.

2. The ST series i.e. ST65T26-1N90-EM, which means 65 KW; this kind of compressor has two oil circuit.

3. The SX series i.e. SX, Relatively large flow rate.

Weatherford, JW “Gemini” and Kraus “Arial” compressors

There are different types of compressors:

1. There is types that has all the stages on two shafts

2. There is types that has the stages on 4 shafts as shown in figure, but one of the major

disadvantages of this compressors is that any trouble in 3rd stage of A or B means a trouble in the

corresponding 4th stage

There is another categorization from the flow point of view

Hint: this mechanism has nothing to do with single acting and double acting mechanism, because double

acting means that it compress I both direction, that will be explained later, and this technique called

double cylinder

Example:

1. H302/G3306 N/A, 02 means to shafts, G means gas combustion engine, 06 means no. of the

cylinders, N/A means natural aspiration.

2. H304/ELECT 250, 04 means 4 shafts, ELECT means electrical motor ,250 hp

Horizontal reciprocating compressor clearance pocket:

Clearance pocket exist to vary the compressors’ output flow rate, as you increase the volume of the first

stage the flow rate decrease, since during the compression process will remains some compressed gas in

the end of the stroke so it will need to expand this gas first as the piston go away in order to open the



24

inlet valve since the valve will open just in case of the inside pressure less than the outside in to intake

the gas for the second compression.

Components and theory of operation of the reciprocating compressors

Main Components

Crank Shaft: it is the prime mover for all the compressor parts and it is operated by external

mover that could be internal combustion engine of electrical motor



25

Connecting Rod: it is the part that responsible for the transmission process of the rotational

motion of the crank shaft to a linear motion.

Liner & cross head: the motion that is produced by the connecting rod is random that is why we

use the liner & cross head to organize this motion to uniform linear one.

Piston: it is connected to the cross head to transmit the motion plus piston rings to prevent the

gas leakage.

Cylinder head: it is the part of the compressor at which the compression process occur where is

the valves exist

Valves: there is two types of valves there is inlet valves and out let valves, also there is types of

valves that consists of both inlet valves ”Suction” and outlet valves “Discharge”.

Packing:*

General theory of operation

For simplicity, when the electrical motor rotate the crank shaft, the crank shaft rotates gives random

motion, here comes the role of the cross head and the liner to organize it and make the motion

uniform linear reciprocation motion, this motion is transmitted to the piston which is connected to the

cross head, In order to make the stroke from the top dead point to the lower dead point.

The previous explanation was for a simplicity process of one stage. So in case of high pressure

difference between the output and the input, we will use multistage compressor.

Also our compressor varies according to the station sites, since the input to this compressor comes

from the Egyptian gas’s network which varies according to its’ use home or industrial so the suction

varies from 2-30 bar but the most common working pressure is 6 bar.

The four stages are approximately like follows.

1st stage 4-20 bar.

2ndstage 20-60 bar.

3rd stage 60-120 bar.

4th stage 120-220 bar.

The suction process occur as follows when the piston moves from the top dead point to towards the

bottom dead point the volume inside the stage increase and the pressure decrease till the inside

pressure is less than the outside pressure so the suction valve inlet the gas. Then when the piston is

moving from the bottom dead point towards the top dead point the pressure inside become larger

than outside since the volume decreases, that makes the outlet valve discharge the gas inside the

stages.

2.2.1 Weatherford compressor operation



26

2.2.1.1 compressor

When the switch is set on “Automatic”, the PLC revise all pressures inside the Air tanks to

insure that it didn’t fall under a certain level that secures a total control on the actuator valves.

Also in case of the falling of the air’s pressure under a certain level the PLC gives it a signal to

restore the pressure.

The pre lubrication operation comes immediately after the air’s pressure check stage. Where

there a signal sent to air solenoid that sent air with pressure 2- 5 bar to the pre lubrication

hydraulic piston to insure that the oil reaches critical points then after a certain period “30

sec” the oil’s pressure increase then the hydraulic piston restore its position and the solenoid

ventilate the air in the piston.

After the pre lubrication process the PLC send three main signals, the first one to open the

suction actuator to begin the worm up process, when the worm up process ends the second

signal goes to the bypass actuator to close it and opens the Discharge valves.

After closing the bypass actuator the gas comes from the suction regulator to the scrubber for

separation of the condensate then it goes to the gas filter for purification process then the gas

goes to the pressure regulator to regulate it.

After the gas increase its pressure in the first stage it exits to a scrubber to separate the

condensate impurities that result due to the compression process afterward to a cooler. To

condensate the heat compression effect. Then to the second afterward to the third finally to

the fourth stage. The gas exits the last stage with pressure 240 bar at least.

When the compression process ends after the banks reach its’ full pressure, the PLC gives a

signal to open the bypass and close the discharge valve to entre the cool down process. At

mean while it keep monitoring the delta bank pressure, in case the pressure falls down, again it

starts to work again to compensate the delta pressure. If the banks pressure don’t fall the PLC

gives 2 signals one to close the suction valve and the second to the motor to shut it down.

2.2.1.2 Lubrication cycle

Lubrication cycle components

1. Gear pump: it is a oil pump that is coupled with the crank shaft

2. Block divider “spider”: that divide the oil to lubricate the stages parts

3. Plunger Piston

4. Pre lubrication piston

5. Oil filter



27

6. Compensation tank

7. Oil level switch

8. No flow switch

9. Cooling unit for the gases

10. Check valves

Theory of operation

As explained previously, the pre lubrication operation comes immediately after the air’s pressure check

stage. Where there a signal sent to air solenoid that sent air with pressure 2- 5 bar to the pre

lubrication hydraulic piston to insure that the oil reaches critical points then after a certain period “30

sec” the oil’s pressure increase because the oil pump is coupled with the crank shaft then the hydraulic

piston restore its position and the solenoid ventilate the air in the piston.

When the oil pressure increase the oil’s pump push the oil to the plunger pump, that compress the oil

to a higher pressure, also it send it to the cylinders and packing through the divider block, and the

check valves insure that the oil won’t return back

2.2.1.3 Cooling circuit

The cooling component in the station:

1. Gas air cooler : It is the same as the car radiator

2. Forced Cooler Fan: it is a huge fan coupled with the crank shaft in the 600 m³/hr or drove by

electrical motor like those of 1200 m³/hr stations

2.2.1.4 Sequential panel

It is a panel that contains a number of solenoid that are controlled through the fill minder card in order to

organize the filling process according to the appropriate sequence

2.2.1.5 Dispensers

It is the machine, through which the car filled with gas, and it has a flow rate of 10 m³/hr, the dispenser

main components are as follow:



28

1. Computer unit “MODEL 33”

2. Micro motion transmitter

3. Mass flow sensor

4. Control valves

5. Fill minder card

6. LCD display

7. Fueling hose “Break away connection, Short hose, three way valves, refueling coupling”

8. Auxiliaries “pressure transmitter, temperature transmitter, pressure safety valves, manual

ventilation valves check valves, excess flow valves ”

2.2.1.6 Flow calculations “operation”

There are many types of flow meter’s company, we are dealing with 2 main companies flow safe “micro

motion” and Enders Houser “proline”, also there are many flow calculations’ method such as

electromagnetic, coriolis, ultrasonic, vortex, thermal and differential pressure. Each of this method is used

according to the application field even they could be used for most of it

From the basic ideas that if we are going to measure the flow of a certain gas that we need a mass flow

meter. And due to the coriolis high accuracy we always use coriolis method

Coriolis method

Coriolis force occurs when a moving mass is subjected to an oscillation perpendicular to the direction of the

flow. The measuring system actually determines and evaluates the resulting effect on the measuring tubes.

The system will measure several parameters simultaneously: mass, volume, temperature, density and

viscosity

The flow meter consists of two main parts the flow meter and its transmitter, the flow meters measure the

flow and send the data to the transmitter that send it as a signal with frequency to the Model 33 that

calculate the price and display it on the LCD

2.2.1.7 Car Charging process: “operation”



29

Once the charging coupling plugged in the car and pushes the micro switch. The micro switch

sends a signal to the PC “model 33” to reset the counters at mean while the fill minder gives a

signal to open the control valve for one second. To indicate

The car’s cylinder pressure

The ambient temperature

The fourth stage’s temperature after the cooling process

According to that it decide the following

From which bank the charging will start

The target pressure at which the charging process ends “target vehicle

pressure”

The dispenser start to charge the car until the car’s cylinder pressure reaches the bank pressure at this

while the fill minder gives a signal to close the low pressure actuator and opens the medium bank then the

third.

In case that the pressure of the cylinder didn’t reach the targeted pressure the PLC gives a signal to close

the banks actuators and open the direct fill valve. And when the cylinder reaches a targeted pressure the

fill minder gives the signal to the control valve to end the charging process by closing the control valve

2.2.2 Safe compressor operation

2.2.2.1 Compressor

The gas entre the compressor through a flange then to an entrance pipe to a manual ball valve, which have

to states either fully opened or fully closed. This valve is used to close the gas’s path in case of maintenance

operation on the compressor.

After that the gas pass through a gas filter for filtration of the gas from impurities, there is a differential

pressure gauge on this filter which measure the gas’s pressure after and before the filtration, in case that

the filter works perfectly the pressure after and before the filter will be the same but in case of the filter

has a problem there will be a difference in pressure.

The filter’s gauge has ranges first the black region at which the filter is working well, and there is the red

region at which the filter should be replaced. This filter should be daily drained from any impurities or

condensates inside it. Inside the filter there is a level switch that in case of the condensate’s level increase

it sends a signal to the PLC to shut the unit of until they drain the filter.



30

After the filter the gas pass through a check valve to prevent the gas from retuning to the network,

afterward the gas goes through pressure damper to absorb any oscillation in the gas’s pressure, so the gas

exit the pressure damper with constant flow rate.

When the gas exit the pressure damper it face the inlet shut off valve which is a pneumatic valve that is

controlled through the PLC, this valve opens and closes automatically when the compressor starts and

stops.

Then the gas passes on a pressure transmitter “PT” to measure the entrance pressure, this pressure

transmitter measure the pressure mechanically and translate it into an analog electrical signal. Then the

gas goes to a pressure safety valve “pressure relive valve, P.S.V” that escape the excess pressure in case its’

increase than a certain limit, Example The P.S.V for the inlet gas’s pressure is from 26-30 bar there will be a

P.S.V withstands 40 bar afterward the gas entre the first stage.

After the compression the gas gain temperature due to the heat compression effect, that is why the gas

exits the stage to a cooler to compensate its temperature “which will be explained later” after the cooler

the gas passes on a temperature transmitter “TT” to send it to the PLC then the gas passes on P.S.V then in

entre an inter stage scrubber to filtration of the gas from condensates and impurities that result due to the

compression process, then the gas goes to the next stage.

How to drain the condensate?

1. Insure that the two valves that are on the drain line are tightly closed

2. Open the ball valve slowly

3. Open the needle valve slowly “rotate the black hand slowly” until you hear the sound of the

condensate, you leave it until you hear the sound of gas exit.

4. Close the ball valve first then close the needle valve

Hint

It doesn’t mean that if you opened the needle valve that the condensate will exit the filter in a higher flow

rate because in that case the gas will exit leaving the condensate inside

2.2.2.2 Lubrication cycle

Lubrication cycle components:

1. 2 oils pumps that are operated by electrical motors

2. Oil-water heat exchanger



31

3. Lubrication oil press manual adjust

4. Maintaining oil press manual adjust

The lubrication circle has to main parts inside safes’ compressors, they are Lubrication circle and

maintaining circle, those circuit are driven by 2 pumps coupled with an electrical motor’s shaft

The lubricating circle is responsible for the lubrication of the main moving parts in the compressor,

maintaining circle is responsible for the pressure on the piston to keep it stick with the cam; each of those

circuits has an oil pressure regulator.

2.2.2.2.1 Lubrication circuit

The electrical motor works on rotation of the oil pump that work to push the oil to the pressure transmitter

PT that transmit the oil pressure to the PLC, that will stop the compressor in case of the pressure of the

lubrication falls beneath a certain level, afterward the oil goes to a water cooler that cool the oil’s

temperature down before it entre the compressor in order to cool and lubricate its parts. Then it exits the

compressor on a regulator. Then it meet the oil that exit the maintaining circuit and together return to the

oil pan to lubricate the crank shaft after that to a filter has an indicator that indicate its state of filter then

to an oil tank. In case of that filter is stuck there is another path with check valve on it to ban the reverse of

the flow.

2.2.2.2.2 Maintaining circuit

The electrical motor works on rotation of the oil pump that work to push the oil to the pressure transmitter

PT that transmit the oil pressure to the PLC, that will stop the compressor in case of the pressure falls

beneath a certain level, then it goes to a filter to filtration process. Then the oil enters all the stages to push

the piston to keep it stick with cam then it exit to entre oil regulator afterward it meet the oil from the

lubricating circle.

We plug the nest component on the oil tank.

1. Temperature transmitter to transmit the oil temperature to the PLC top shut the unit down in case

of the temperature increase than a certain limit

2. Pressure transmitter to transmit the oil pressure that result due to the increase in the oil level

2.2.2.3 Cooling circuit

Components of cooling circuit



32

1. Gas water heat exchanger

2. Water air heat exchanger

3. Water pump

4. Water compensation tank

5. Manual control flow valve

6. Manual control pressure valve

7. Chiller “New SW series”

After each stage there is a gas water heat exchanger that transmit the heat to the water which by the aid of

the water pump is pushed through the pipes to the water air cooler then the water return after it maintain

a cold temperature. We must adjust the right water’s cycling speed to avoid the boiling of the water.

Hint

Mainly there are two types of coolers Tube-Tube and shell-tube, generally the gas flow is opposite to the

water flow.

The yellow arrows indicate the gas flow and the green arrows indicates the water flow

In new systems

After the normal circuit of the water cooling system inside the compressor, the fourth stages is consisting

of two main stages first classical cooling by heat exchanger and chiller stage which is a unit that force the

temperature of the water into a very low ranges in order to maintain low output gas temperature. This

cooling system make a temperature differences in the output gas about 10 °C. Also the density of the

flowing gas will be larger as the density increases when the temperature decreases. That leads to increase

in the mass flow, In addition to the cold gas will decrease the use of spare parts like the o-rings of the

coupling instrument.



33

Event:

Once there was an error appears on the screen of the chiller FL that indicate that there is no flow, first we

checked the tank and it was filled with water but we didn’t notice that there are two valves one to make

sure that there is water in the tank and the other was to open the flow to the pump

2.2.2.4 Car charging process: “operation”

Once you take the filling unit from its place in the dispenser. You will notice that the red light is flashing and

then *

Mechanical review:

1. Changing the rotational motion into reciprocating motion

1.1 Crank shaft method:

This is the system is equivalent to the SW mechanism, but this is simple diagram for the system,

every piston is shifted with a certain angle from the other

This is the general method of the crank shaft method

1.2 Cam method:



34

There are two main ways of cams one uses a circle but with fixation not from its axis, and the other

is using an elliptical shape, this technique is usually used in the safe’s ST series, that is why there is

a maintain circuit in those kind of compressor

2. Single acting and double acting method

2.1 Single acting compression

In this method of the single acting compression the piston compress in a stroke and return without

doing any work. That makes the piston find a resistance while going in the outlet stroke while zero

resistance while inlet stroke there is no resistance. So this method you need to equate the pressure

over and under the piston to avoid hammering effect while inlet stroke so you need a kind of bypass, in

order to make what they call pressure pillow

You could find this bypass in SW200F6-EM-110 machine obvious when you stand in front of it also it exist

Gemini compressor to. But its function becomes useless in presence of double acting method of

compression.

2.2 Double acting compression method

In this method the piston compress at both ways inlet and outlet because while inlet stroke at a certain

side there is a compression stroke on the other side. So there is no place to pillow method.

Bypass

P in P out

P in

Sealing

Piston

In

Out

Clearance pocket In

In

Out

Inlet Valves

Outlet Valves

Stroke



35

The curvature on the beam indicates the in and outlet valves. Since the curvature on upper side indicates

the inlet and the lower side indicates the outlet.

What is the clearance pocket?

The clearances pocket is a method to control the flow rate of the machine through controlling the volume

of the first stage. Since in case the first stage’s volume increases that results not all the gas which has been

compressed to go out of the room, so a residual pressurized gas remains in the room that lead to a delay in

opening the inlet of the gas in the room since it will need an extra displacement to lower the pressure. So

it takes longer time hence the output flow rate decreases. And vise versa

3. Bearing

There are two main types of bearing friction and Antifriction bearing

3.1 Friction

1. Ball bearing

2. Needle bearing

3. Thrust Bearing. Picture needed*

There are many types of bearing you could find more SKF catalog; it is used in high speed applications, and

normal and medium loads.

Lubrication method:

1. Greasing through “Injection Method” is method used for open types of bearing.

2. Self lubricated is a method that used for closed type.

You could identify that the bearing is open or closed type through the code that is written on the ball,

where 2Z stand for closed type bearings, while C3 is used for open type.

Usage: this type of bearing is usually used in small and medium size machinery as single stage centrifugal

pumps, air compressor, P.D pumps, and Turbo chargers.

3.2 Antifriction

Out



36

1. Sleeve friction

This type is used for high speed applications with high loads

Lubrication method:

1. Oil film lubrication

2. Hydro dynamic lubrication

3. Hydro static

Usage: Anti friction bearing is usually used in large machinery like steam turbines, gas turbines, hydraulic

turbines, Multi-stages machines.

How to read the number of the bearing?

i.e. 6322, to calculate the bore diameter from this number take the last to numbers “22” and multiply them

by 5

Event:

Be careful with the material selection of those types of bearing. Since there was a certain package that we

import that made from a very bad material that when we use it two days and they broke down. Because

they can’t stand the heat formed inside the compressor

4. Gears:

Gears are used as a power transmission element as in automotive gearbox or as reduction gear elements as

in drivers.

There are many types of gears:

1. Spur gear

2. Bevel gears

3. Helical spur gears

4. Helical bevel gear

5. Worm gear

When you form a system of gears they are called train of gears those kind are

1. Simple gear train

2. Planetary gear train, this type is used in hydraulic power, power transmission



37

5. Pumps

There are two main types of pumps. There are PD “Positive displacement” pumps and Dynamic pumps.

5.1 PD pumps

Displacement action pumps produce high pressure and low flow rate. And its main types are reciprocating

(plunger and pistons) and rotary (vane-screw-lobe-gears)

5.2 Dynamic pumps

Dynamic action produces high flow rate and low pressure. And it is used for multistage for high pressure. Its

types are axial, radial, mixed.

6. Engines

There are two types of mechanical engines internal and external compassion engines.

6.1 Internal compassion engines

a. Spark internal compassion engine “SIE”

It depend on a spark to ignite the mixer, it has many types according to the strokes. There are many

types but mainly they are cylindrical or rotary engines.

b. Compression internal compassion engine “CIE”

It depend on the temperature to ignite the mixer, mainly it depend on organic oils in working.

6.2 External compassion engines



38

Mainly they are used in GT turbines “gas turbine” but it is a very low efficiency engines, and it

depends on the exhaust in order to take the work.

7. Alignment of Drivers axis

There are two main parameters in the alignment first the radial alignment and the angular alignment.

7.1 Radial alignment

It is the radial parallel shift of the main axis

7.2 Angular alignment

It is the deviation of the axis with an angle with the main axis

When we measure the alignment in the periodical maintenance we have a device with two gauges one of

them indicate the radial deviation and the other indicate the angular. The maximum allowed reading for

the gauges is 5 and zero is the best.

What is the end play?

It is an axial clearance in the crank shaft driver or the driven in

order to give free space for the coupling to move axially. And the

readings should be in the range of 0-5 saaw

8. Types Coupling

There are two types of coupling flexible and rigid coupling

8.1 Flexible coupling

It is a kind of coupling where the driver and the driven are connected together through rubber

connection or shims, and those type of coupling are used in our compressors

Shims: are metal slices with high elasticity

Axial

Angular

Driver Driven



39

8.2 Rigid coupling

It is a kind of coupling that the driver and the driven are connected tightly together through a 2

flanges and a sets of bolts, this kind of coupling is used for the small machines

8.3 Chiller

Chiller is a device is used to decrease the temperature of the outlet gas, which means the increase

of the density of the out put gas. Also there is another advantage from using the chiller which is

that the O-rings of the coupling will last longer.

8.4 Friction joint

The friction joint is a mechanism which fix

any flange with the crank shaft. It consist

of two parts when you tight the bulks a

part of it goes down in order to hold the

crank shaft and the other part hold in the

flange.

2.3 Piping and Instrumentation

2.3.1 Piping and fittings

This next part is mainly about parker fittings and was written according to their metaphors and

perspective of fitting categorization

Driver Driven



40

2.3.1.1 Tube fittings (CPI & A-LOK):

There are two main standards for fittings; the first standard is the American standard that mainly

depends on the ferruling on the tubes by one cycle and half, and the European standards that

depend on the flaring of the tubes.

Also there are two types of threads there are NPT “national piping taper” and BSP “British standard

piping”.

NPT: is 55 thread’s angle. Pitch measured in inches, truncation of the root and crest are flat, taper

angle 1°47’

BSP: 55° thread angle. Pitch measured in inches. Truncation of root and crest are flat. Diameter

measured in inches.

Hint:



41

Always we use ferruling with WF and JW while safe’s systems use the flaring method

There are many categories for fittings

Always U.S.A use the inches in measurement while the international standards is the metric

standard



42

When you are ordering a tube fitting the metaphors for the fitting is actually indicate the

specification of the fitting

Example: The part number shown below is the parker A-LOK stainless steel male connector for 1/2’’

O.D. tube (-8) and 1/4’’ male pipe thread.

How to order CPI Inch Parts:

CPI/A-LOK

fittings

Tube to male fittings

Tube to Female Fittings

Tube to Tube fittings

Port Connectors

37° Flare (AN)to

CPI/A-LOK

Tube to O-Ring seal

Tube to welded system

Analyticacl fittings

Bared Fittings

Components



43

How to order CPI inch parts

How to order A-LOK inch parts

Parker CPI/A-LOK tube fitting re ordered by part number as listed in this catalog

Size: Tube and pipe thread sizes are designed by the number of sixteenth of an inch (1/2’’ tube =

8/16’’=8). (1/4’’ pipe thread = 4/16’’ = 4).

Straights & elbows: call out largest CPI/A-LOK tube end size first followed by the smaller CPI/A-LOK

tube end or pipe thread size

Tees and cross: For drop size tees-first size the run (1 to 2) and then branch (3).Example- the size

designator for male run tee for 3/8’’ O.D. tube and 1/4’’ male pipe thread would be 6-4-6. For

crosses – first size the run (1 to 2) and then the branch (3 to 4). For tees with all ends the same, use

the tube and size before and after the style designator; i.e. 4-4-4 JBZ (CPI), 4ET4

Material: Basic material type (B = Brass, SS or 316 = stainless steel, type 316; S=steel; A= aluminum;

M = Monel; HC = Hastelloy C-276 ; IN = Alloy 600; SS20 = carpenter 20 ;T= titanium)

How to order metric parts:

How to order CPI metric parts

8

1st End 1/2'' tube

O.D

4

2nd End 1/4'' Pipe

Thread

FBZ

Fitting Type male

connector

SS

Material stainless

steel

8

1st End 1/2''

tube O.D

MSC

2nd End 1/4'' Pipe

Thread

4

2nd End 1/4'' Pipe

Thread

N

Thread Type NPT

316

Material stainless

steel



44

How to order A-LOK Metric parts

Parker CPI/A-LOK tube fitting are ordered by part number as listed in this catalog.

Size: Metric Tube is designed in millimeters and prefixed “M” (i.e. 12 mm tube= M12) the pipe

thread size is written as a fraction (i.e. 1/4 NPT = 1/4N).

Tees & crosses: for drop size tees – first size the run (1 to 2) and then branch (3). Example – the size

designator for male run tee for 6 mm tube and 1/4’’ male pipe thread would be 6-4-6. For crosses –

first size the run (1 to 2) and then the branch (3 to 4). For tees with all ends the same size, use the

tube end size after the style designator; i.e., JBZ 4-4-4 (CPI), ETM4 (A-LOK).

Material: Basic material type (B = Brass, SS or 316 = stainless steel, type 316; S=steel; A= aluminum;

M = Monel; HC = Hastelloy C-276 ; IN = Alloy 600; SS20 = carpenter 20 ;T= titanium)

Thread types:

N= NPT

K=BSP taper

R or BR=BSPP

M=metric

R-ED= BSPP

Assembly and remark Instructions:

1. Parker instruction tube fittings are completely assembled and ready for immediate use. Simply

insert the tube as illustrated until it bottoms in fitting body. (If the fitting is disassembled, note that

the small tapered end of the ferrule go into the fitting body.)

GBZ

Style female

connector

12

Tube O.D 12mm

1/4

Thread Size 1/4''

K

BSP

SS

Material stainless

steal

M12

Tube O.D 12mm

FSC

Style Female

Connector

1/4

Thread Size 1/4''

N

Thread type NPT

316

Material stainless

steal



45

2. Tighten nut finger tight. Then tighten nut with wrench an additional 1- ¼ turns. Hold fitting body

with a second wrench to prevent body from turning. It is helpful to mark the nut to facilitate

counting the number of turns. But for the tubes less than 3/16’’ or less than 4mm use ¾ turn.

Usually we chose the fitting according to the working pressure and the temperature.

2.3.1.2 Instrument Pipe & ISO Conversion Fittings

Those kind of fittings are originally manufactured with Brass and stainless steal for special order you should

contact the company

1. Instrument and Pipe fitting:



46

Pipe Fitting

Male Hex Long

Nipple Male Close Nipple

Adapter

Male Hex Nipple

Female hex

Coupling

Reducing Bushing

Male Elbow

Femal Elbow

Female Elbow

45° Street Elbow

Female Tee

Street Tee

Male Branch

Tee

Male Tee

Female Cross tee

Pipe Cap

Hex Head Plug

Hollow Hex Plug

Straight Thread Adapter

Hex Head Plug

Hollow Hex Plug

Straight Thread

Reducer

Male straight head to

female NPT thread

Connector to SAE straight

thread



47

NPT threads:

The National Pipe Taper NPT thread has a thread flank angle 60 inclusive and is mainly used in the

petrochemical and process industries.

NPT – National Pipe Taper Thread for connections where pressure-tight joints are made on the thread

utilizing a thread sealant.

How to order

Size: pipe thread sizes are designed by the number of sixteenth of an inch

Thread Type: All pipes thread are national pipe taper NPT unless other wise designated.

Tees and Crosses: For tees that are the same on all ends the size designation is as follows:

6-6-6 FT-B would be a 3/8’’ NPT female tee in brass, a ¼’’ NPT Female cross in 316 would be a 4 FX-SS.

2.3.1.3 Cylinder connections

6

1st End 3/4'' NPT Male Pipe

4

2nd End 1/4'' NPT

Pipe Thread

MHN

Fitting type Male Hex

Nipple

SS

Material 316 SS



48

2.3.1.4 Partek PFA/PTFE Products:

Parker Hannifin’s Partek operation facilities manufacture flow control products for use in fluid systems

where corrosion protection is required or where media purity must be safeguarded.

The wetted surfaces of the entire product are chemically inert, made of PFA or PTFE

External material are made of polyethylene (HDPE), polyvinylchloride (PVC), polyvinylidenefluride (PVDF),

perfluoroalkoxy (PFA), ABS plastic knobs are used in some

There are many ways of connecting those kinds of tubes:

cylinder connections

CGA Inlet connection

components

CGA Outlet Adapters, Blank caps

& Plugs

Cylinder Value

Outlet and caps



49

Fluor polymer tubing products:

Chemical properties

Resistivity to corrosive agent

Non-solubility

Long term weather ability

Non-adhesiveness

Nonflammability

Electrical properties

Low dielectrical constant

Low dissipation factor

High arc resistance

high surface resistance

High volume resistivity

Mechanical properties

Flexibility at low temperature

Low coefficient of friction

Stability at high temperature

Fluid handling tubing and pipe

High purity tubing

Retractable coils and formed shapes

Fractional industrial and heavy wall tubing



50

Striped tubing

Welding and standard rod

Tubing for air and water sampling

Schedule 40 and 80 pipe

Metric sizes

Electrical insulation tubing

Spiral cut cable warp

Convoluted tubing

Heat shrink Tubing

2.3.2 Ball valves

These are the main categorization

of the ball valves.

2.3.2.1 B series Ball values

First those kind of valves could easily used manually , pneumatically and electrically actuated two-way B

ball series ball valves provide quick ¼ turn on off control of fluids utilized in process and instrumentation

application. A broad selection of valve body, seats, seal material provides a wide range of pressure and

temperatures at which the valves may be used.

B series

MB series

HB series

SWB series



51

2.3.2.1.1 Two ways B series Ball Valves

Item # Part Description

*1 Connector O-ring

*2A Seat Retainer

*2B Seat

*3 Retainer seat

*4 Ball

*5 Body

*6A Stem

*6B Stem seal

*6C Stem washer

7 Packing nut

8 Handle

9 Handle set screw

10 Panel nut

*11 End connector

These kind of ball valves series are manufactured from many types like 316 stainless steal that could stand

up to 6000 PSI (416 bar) which they call B8 series

The sign * means that it is a wetted part

2.3.2.1.2 Three way B series ball valves

Those kind of valves could easily used manually, pneumatically and electrically actuated three way B series

valves may be used as diverting or selecting valves for fluids utilized in the instrumentation process.

There are two schemes of operation for this valves either the inlet port is the one in the bottom that will

give it a higher pressure limit (6000 PSI) or from a side port and it will give it a lower working pressure

(3000 PSI).



52

A. Diverting Valves:

You could identify this valve by the absence of the Diverter Valve.


*1 Connector O-ring

*2A Seat Retainer

*2B Seat

*3 Retainer seat

*4 Ball

*5 Body

*6A Stem

*6B Stem seal

*6C Stem washer

7 Packing nut

8 Handle

9 Handle set screw

10 Panel nut

*11 End connector

B. Selector Valves

You could identify this valve by the


*1 Connector O-ring

*2 Seat

*3 Sear retainer

*4 Spring

*5 Seat retainer washer

*6 Back-up ring

*7 Connector O-ring

*8 Stem retainer O ring

*9A Stem

*9B Stem washer

*9C Stem washer

10 Packing nut

11 Panel nut

12 Handle

13 Ball

14 End connector



53

How to order

1. Two way Valves:

4Z 4F – B6L J – BP

Describe a B6L ball valve with a ¼ ‘’ CPI end connection for port 1 and a ¼ ‘’ female NPT end

connection for port 2, PTEF seats, PTFE stem and body seals, Brass construction, with a

panel mounting nut.

8A * - B8L J – BN – SSP

Describe a B8L ball valve with a ½’’ A-LOK end connection for ports 1 and 2, PTFE seats,

Buna-N rubber stem and body seals, stainless steel construction, with a panel mounting

nut.

M3A * - B2L J2 – VLT – SSP

Describe a B2L ball valves with 3 mm A-LOK end connections for ports 1 and 2, PCTFE seats,

fluorocarbon rubber body

Hints & key

a. When we are talking about the size of the fittings under the American standard so the 4

indicate 4 of 16, in case of metric standard you will find a capital Letter M before the number

that indicates the size in mm.

b. Z means CPI fittings while A means A-LOK

c. * means that the input port is similar to the output port.

d. B6 and B8 is the series of the ball

e. J means PTFE “Polytetrafluoroethylene” while J2 means PCTFE “Polychlorotrifluroethylene”

f. SS means stainless steal while B means Brass,

g. P means panel mounting nut

2. Three way diverter valves:

4Z-4Z-4F – B6X J2 – V - BP

Describes a B6L ball valve with ¼ ‘’ CPI end connection for side ports a 1 and 2, ¼ ‘’ female

NPT end connection for bottom port 3,PCTFE seats ,fluoro rubber stem and body seals,

brass construction and mounting nut.

2Z -B2X J2 - SSP

Describe a B2L ball valve with 1/8 ‘’ CPI end connection for ports 1, 2 and 3 PTFE seats,

PTFE stem and body seals, stainless steel construction and panel mounting nut. Note: if 1,

2, and 3 are the same eliminate the port 2 and port 3 designators.

3. Three way selector valves:



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4M 4M 4F – B6X S2 – EPR – SSP

S means spring and they write it instead of the J

There are many types of actuator that can fit with the B series ball valves

a. Manual valves: which have round, Lock-out Devices.

b. Actuation Options:

a. Double acting: it has two main signals, one of them to open it and the other to close it.

b. Spring return: the spring make the restoring torque

c. Electrical actuator: it is actuated by an electrical signal

Note:

When ordering actuated B series ball valves. O-ring stem seals or live-loaded stem seals are recommended

to minimize the need for stem seal maintenance.

Also if we noticed the difference between the two 3 ways valves “diverter and selectors”, we will find that

we should use selector “the one with the springs” since we have the high pressure comes from a side port

not from the bottom one.

2.3.2.2 MB series Ball Valves

Parker MB series ball valves with their rugged compact design, offer positives shut off or directional control

of fluids in process ,power and instrumentation applications. The unique one pieces seat/packing design

insures excellent sealing characteristics while accommodating a superior temperature range and cycle life.

These valves working pressure is up to 3000 PSI (207 bar).

**** Picture

2.3.2.3 HB series ball valves

Parker high pressure HB4 series ball valves, featuring super case ball and trunnions, provide reliable shut-

off or switching function. The super case trunnions style ball enhances the resistance of the trunnions

against seizure and the resistance of the spherical ball to particles abrasion. The compact and rugged

design employs spring-loaded seals for high cycle life and low operating torques at pressures up to 10000

PSI (689 bar).

These valves working pressure is up to 10000 PSI with PEEK seats.

****pictures++++materials

Available end connections:

Z- One ferrule CPI, A- two ferrules A-LOK compression and F- ANSI/ASME B1.20.1 internal pipes thread



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2.3.2.4 Swing-out Ball valves

Parker’s three-piece SWB ball valves are durable valves that can handle the pressure and piping loads. The

centre section can swing out to the quickly and easily replace seats, seals and the ball without major

disruption to the piping system

***picture needed

2.3.3 2.3.2 Dispensers

These systems have been designed for the purpose of filling motors vehicles, which based on mass flow

meters that work on coriolis forces; such technique has many advantages on the traditional way which

determines the quantity of fuel by using approximate calculations.

The following are some of the advantages

Precision of the measurement (±1%). The mass of delivered gas is determined through direct

measurement, and this is an independent parameter not affected by pressure or temperature’s

condition.

Also the dispenser is equipped with a system that fills a tank respecting gives limits of the pressure

and temperature respecting a maximum pressure inside the vehicles tank.

The principle of measurement is based on the controlled generation of coriolis forces, existing on a system

which simultaneously presents a sire motion and a rotating motion.

The mass flow metering unit basically consists of a casing containing two aligned measuring tubes, trigger

and optic sensor; these measuring tubes vibrate in counter phase in a diapason like manner. The coriolis

forces acting on the measuring tubes create changes in the position of the oscillation phase of the tube.

During the transit of the natural gas mass, the oscillation is retarded at the inlet side and accelerated at the

outlet side. So the larger mass flow the greater is the difference of phases, at zero flow both of them are

identical.

2.3.3.1 Safe’s MOD.ESP 22/3

Those kinds of dispensers are self sequencing at mean while they are self controlled. Their operation is as

follows.

The gas sent directly from the compressor or from the storage system reaches the dispenser from the low,

medium and high pressure inlets lines.



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Here the gas is filtered by the filters and intercepted by the driven valves operated by the solenoid

valves(7*), hence envoy to the meters(1), which not only meters the mass but also controls any excessive

flow of the gas via a built in electronics detector

For the safety motives of the two hoses there are break away then there are the flexible hoses, then the

three way valve.

CPU’s sequence of operation as follows, the CPU head performs a initialization cycle and if all the internal

check is negative, it activate the driven calve (6)and start to refuel from the low pressure, during this phase

the various displays are tested when all the sections are lit up one after another.

The gas start to flow through the metering unit that sends 100 pulses every Kilogram of the gas dispensed.

The head switch from an actuator to another when the flow goes bellow a certain value, but this switch

doesn’t happen immediately after the decrease in the flow but it takes a few delay seconds.

Postponed topics:

PLC types and Soft wares

Inverters and Soft starters’ circuits

Flow meters types and theory of operations

Dispensers and its cards

Sequential panels and pneumatic valves and its types

Fault log

Mechanics:

Unlades

Investor Relations

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