Netafim Techline CV Design Manual

Techline® CV Design Guide

Subsurface or On-Surface

Pressure Compensating Dripperline

with Check Valve

N E T A F I M T E C H L I N E® C V D E S I G N G U I D E

TABLE OF

CONTENTS

INTRODUCTION

Overview ....................................................................................................................... 3

DESIGN CRITERIA

Site Survey ................................................................................................................... 4

Point of Connection ...................................................................................................... 4

BASIC DESIGN STEPS

When Should You Use Techline CV ..............................................................................

Choosing the Proper Techline CV ................................................................................ 5

Techline CV General Guidelines Chart ......................................................................... 5

Types of Layouts .......................................................................................................... 6

"GRID" Layout .............................................................................................................. 6

"Lite" Layout ................................................................................................................. 6

What Do These Layouts Have in Common? ................................................................ 6

Basic Grid Layout ......................................................................................................... 7

Basic Lite Layout .......................................................................................................... 7

How to Calculate Equal Techline CV Row Spacing ...................................................... 7

Length of Techline CV Rows ........................................................................................ 8

Techline CV Maximum Length of Laterals Chart .......................................................... 8

Center Feed Grid Layouts ............................................................................................ 8

Other Grid Layout Considerations ............................................................................... 9

Zone Water Requirements .......................................................................................... 10

Techline CV Flow per 100' Chart ................................................................................ 10

Fittings ........................................................................................................................ 11

Staples ....................................................................................................................... 11

Line Flushing Valves ................................................................................................... 11

If An Automatic Line Flushing Valve is Desired .......................................................... 12

If An Automatic Line Flushing Valve is Not Desired ................................................... 12

Air/Vacuum Relief Valves ............................................................................................ 13

Filters .......................................................................................................................... 14

Pressure Regulating Valves (PRV’S) ........................................................................... 14

Low Volume Control Zone - Low Flow ....................................................................... 15

Low Volume Control Zone - High Flow ...................................................................... 15

Slopes and Berms ...................................................................................................... 16

Techline Check Valve .................................................................................................. 16

Trees ........................................................................................................................... 16

Pressure & Flow Checks ............................................................................................ 17

Calculating Precipitation Rates .................................................................................. 17

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N E T A F I M T E C H L I N E® C V D E S I G N G U I D E

TABLE OF

CONTENTS

(continued)

TECHLINE CV IN TURF

Techline CV in Turfgrass ............................................................................................. 18

Where and Why to Use Techline CV in Turf ................................................................ 18

Tips for Using Techline CV in a Newly-Sodded Lawn ................................................ 19

SPECIAL APPLICATIONS AND TIPS

Parking Lot Islands ..................................................................................................... 20

Electrical Grounding ................................................................................................... 20

Techline CV Above and Below Grade ........................................................................ 20

TECHLINE CV WINTERIZING INSTRUCTIONS

Techline CV Winterizing Instructions ..........................................................................

Manual Winterization .................................................................................................. 21

Compressed Air Winterization .................................................................................... 21

TECHLINE CV TECHNICAL DATA

Applications, Specifications and Features/Benefits ...................................................

Exploded View of Techline CV Dripper from Above and Below ................................. 23

Design Formulas ........................................................................................................ 24

Specifications ............................................................................................................. 25

Techline CV Application Rate Tables .......................................................................... 26

Techline CV General Guidelines ................................................................................. 27

Techline CV Maximum Length of a Single Lateral ...................................................... 27

Techline CV Flow ........................................................................................................ 27

Disc Filter Sizing ......................................................................................................... 28

Techline CV with Techfilter .......................................................................................... 29

Techfilter Installation and Mounting Instructions ........................................................ 29

Techfilter Use and Replacement Guidelines .............................................................. 29

Techfilter Specifying Information ................................................................................ 30

Techline CV Minimum & Maximum Feet for Each Filter Size ..................................... 30

Techfilter with Techline CV Model Number Descriptions ........................................... 31

Techline CV End Feed Layout .................................................................................... 34

Techline CV Center Feed Layout ................................................................................ 35

21

22

Installation Checklist ......................................................................................... 36

System Inspection Checklist ........................................................................... 37

Fittings ..................................................................................................................... 38

MOST FREQUENTLY USED CHARTS

Techline CV General Guidelines .................................................................................

Techline CV Maximum Length of a Single Lateral ...................................................... 39

Techline CV Flow ........................................................................................................ 39

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N E T A F I M T E C H L I N E® C V D E S I G N G U I D E

INTRODUCTION

This manual covers the basics of design, installation, and maintenance of Techline CV integral
dripperline. Included are design steps, technical data, design layouts, as well as some design and
installation details and checklists using both the “Grid” and “LITE” layout methods.

OVERVIEW:

• Netafim is the world leader in low volume irrigation. Since the early 1960ʼs Netafim has pioneered
the science of subsurface, on-surface and point source irrigation and manufacturing. Serving
more than 100 countries worldwide, Netafim products are sold into the Landscape & Turf market,
as well as agriculture, greenhouse and nursery, wastewater, mining and forestry.

• The Techline family of products have been used successfully in landscape since 1987 in North
America. Techline CV allows for even more water conserving designs because check valves are
built into every dripper.

• Landscape Architects, Contractors, Nurserymen, Designers and Consultants recognize the
benefits of using low volume and drip irrigation for new plantings because of its accelerated plant
growth compared to overhead spray and rotor irrigation. Coupling the rapid growth with dramatic
water savings and low volume irrigation becomes an important part of any irrigation system.

• With the flexibility and quality of Netafim products, architects, designers, and contractors have
highly sophisticated solutions to client and installation issues by bringing drip and subsurface
components together to grow plants, trees, shrubs, groundcover, and yes, even turf.

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N E T A F I M T E C H L I N E® C V D E S I G N G U I D E

N E T A F I M T E C H L I N E® C V D E S I G N G U I D E

DESIGN

CRITERIA

• Designing with Techline CV follows the same basic rules as designing with Techline, sprays and rotors.

• Point of connection, static and operating pressures, flow rates, and type of materials being irrigated are
the same.

• Designing similar areas into a zone and not mixing products with different application rates is just like
sprinkler design.

• The essential differences include knowing the type of soil you are working with, and the method of
layout you use in the design.

SITE SURVEY:

• Obtain or draw a scaled plan of the site to be irrigated. Identify all slopes on the plan.

• Identify the type of soil (sand, loam or clay).

• Determine types of materials to be irrigated, turf, groundcover, shrubs, plants, and trees.

POINT OF CONNECTION:

• Type of water, potable, well, pump, effluent, etc.

• Pressure & volume available - Static and operating tests.

Note: For Techline CV Technical Product Application & Specifications, see page 22.

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N E T A F I M T E C H L I N E® C V D E S I G N G U I D E

BASIC

Dripper Flow

Dripper Interval

Lateral (Row) Spacings

Burial Depth

Application Rate (in./hr.)

Time to Apply 1/4"

of Water (in minutes)

Clay Soil

0.26 GPH

18"

18" - 22"

.19 - .15

79 - 100

Loam Soil

0.4 GPH

12"

18" - 22"

.43 - .35

35 - 43

Sandy Soil

0.6 GPH

12"

12" - 16"

.96 - .72

16 - 21

Clay Soil

0.26 GPH

18"

18" - 24"

.19 - .14

79 - 107

Sandy Soil

0.6 GPH

12"

16" - 20"

.72 - .58

21 - 26

Loam Soil

0.4 GPH

18"

18" - 24"

.29 - .21

52 - 71

SHRUB and GROUND COVERTURF

TECHLINE® CV General Guidelines

Maximum spacing recommendations: Following these spacing guidelines, dripper flow selection can be increased if desired by the designer.

On-surface or bury evenly throughout the zone to a maximum of 6 inches

DESIGN

STEPS

WHEN SHOULD YOU USE TECHLINE CV?

• Anytime you want to create an even wetted pattern of water throughout an area.

• Since the object of sprinklers is also to create an even wetted pattern, you can use Techline CV
anytime you can use sprinklers.

CHOOSING THE PROPER TECHLINE CV:

• From Table 1, answer two questions:

1. Are you irrigating a Shrub & Groundcover area or Turf?

2. Is the soil Clay, Loam or Sandy?

• Follow the proper column listed under TURF or SHRUB & GROUNDCOVER to identify the proper
Techline CV. Example - If you choose Shrub & Groundcover, with loam soil, 0.4 GPH/18” Techline CV is
the proper choice. (Each dripper will deliver 0.4 GPH and the drippers, mounted inside the tubing, are

spaced 18” apart.)

• What other information is in the General Guidelines Chart?

1. How far to spread out the laterals is listed on the “Lateral (Row) Spacings” line.
(For this example, rows should be evenly spaced anywhere from 18” - 24” apart.)

2. The corresponding application rates and time to apply are listed under the Lateral Spacings

line. (With rows of 0.4 GPH/18” Techline CV every 18” apart, the application rate is 0.29 inches

1

per hour and it will take 52 minutes to apply
rate is 0.21 inches per hour, and it will take 71 minutes to apply

/4” of water. If the rows are 24” apart, the application

1

/4” of water. For other row

spacings, see page 26.)

TABLE 1

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N E T A F I M T E C H L I N E® C V D E S I G N G U I D E

BASIC

Exhaust Header

Supply Header

TECHLINE CV

DESIGN

STEPS

(continued)

TYPES OF LAYOUTS:

There are two layout methods we recommend - “GRID” and “LITE”. Both accomplish the same goal, but
one method will be the preferred method based on what and how you are irrigating.

Basic Techline CV Grid Layout

“GRID”:

• This is the preferred method for installing Techline CV subsurface

• This method uses supply and exhaust headers with rows of Techline CV connected at each end

• The Supply Header delivers water to each row of Techline CV

• The Exhaust Header forms a continuous loop, or return leg, so all rows of Techline CV are being

supplied from both ends

• This interconnection of the piping network comprises the term “Grid layout.” This evens out the flow,

helps ensure water is being delivered downstream of any break in the laterals, and allows for much
easier repairs of any line breaks.

Basic Techline CV Lite Layout

“LITE”:

• The LITE layout is used exclusively on-surface

• It is the fastest and easiest layout method because no supply and exhaust headers are used

• The dripperline simply weaves back and forth throughout the zone in evenly spaced rows.

WHAT DO THESE LAYOUTS HAVE IN COMMON?

• Both methods assume even row spacings will be maintained

• Both methods are designed to flow water in a loop manner

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N E T A F I M T E C H L I N E® C V D E S I G N G U I D E

TECHLINE CV

2" to 4" Setback from Edge

5' 52"

BASIC

DESIGN

STEPS

(continued)

BASIC “GRID” LAYOUT:

• Headers should be indented 2” - 4” from hardscapes and planting areas.

• Headers may be PVC, polyethylene or in zones under 5-GPM, Techline CV or Techline CV Blank
Tubing.

• Headers must be sized to accommodate the flow of the zone without exceeding 5 feet per second
velocity. (Zone Water Requirement calculations are on page 10).

• Start rows of Techline CV 2” - 4” away from the edge of hardscapes, and move across the area with
equal row spacing that does not exceed the recommendations of Table 1.

provide enough moisture to prevent heat damage to plant material generated by hardscapes such as
asphalt). Start rows about 4” away from planting beds.

BASIC “LITE” LAYOUT:

• Water being supplied to the zone is split with a Techline fitting into two directions.
Use a TL075FTEE or TL2W075MA fitting.

• Weave the Techline CV back and forth throughout the planting area with evenly spaced rows.

• Indent the tubing 2” - 4” from hardscapes and planting areas.

• Because water is being split into two separate paths that meet in the middle, the maximum length of the
lateral can be twice the stated limit in Table 2.

• Therefore, to determine the maximum amount of Techline CV you can use in the zone, simply double
the maximum length stated in Table 2.

(The 2” setback will help

NOTE

How to Calculate Equal Techline CV Row Spacing

Example:

• 5 feet x 12 inches = 60 inches

• 60 inches - 8 inches (2 edges x 4” setback) = 52”

• Following recommended Techline CV Row Spacing
for this example, assume 18 inches from Table 1

• 52” ÷ 18” = 2.89 spaces between Techline CV rows

• 2.89 is not a whole number, so round up to the next
whole number, which is 3 (spaces)

• Add 1 (one) to the number of spaces to determine
the number of Techline CV rows

• Determine equal spacing between Techline CV rows. 52 inches ÷ 3 = 17.3 inches

HOW TO QUICKLY DETERMINE THE AMOUNT OF TECHLINE CV IN A ZONE

(Square Footage of Zone x 12) ÷ Minimum Recommended Row Spacing

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N E T A F I M T E C H L I N E® C V D E S I G N G U I D E

BASIC

Manual Line Flushing Valve
Plumbed to PVC or Poly

Techline Start Connection
Male Adapter

Remote Control Valve with
Disc Filter and PRV

Techline® CV Tubing Lateral

PVC or Poly Exhaust Heade

r

LF

LF

Techline Start Connection

PVC or Poly Supply Header

Area Perimeter

Perimeter Laterals
2" to 4" From Ed

g

e

109

325

409

469

0.4

86

256

322

369

0.6

127

427

539

618

0.26

65

194

244

280

0.9

151

459

579

664

0.4

91

274

346

397

0.9

152

458

580

666

0.6

116

348

440

506

0.9

15

25

35

45

Dripper Flow Rate (GPH)

INLET PRESSURE (psi)

120

361

456

523

0.6

177

604

763

877

0.26

TECHLINE CV DRIPPER SPACING

TECHLINE® CV Maximum Length of a Single Lateral (feet)

DESIGN

STEPS

(continued)

LENGTH OF TECHLINE CV ROWS:

• As with overhead irrigation, friction losses through pipe determine how long a length of pipe can be.

• You do not need to go through friction loss calculations for Techline CV laterals. It has already been
done for you.

• Table 2 shows the maximum length of a single Techline CV lateral within a zone.

• The chart also determines what the operating pressure of the zone needs to be. Example - If you
have a 322ʼ lateral of 0.6 GPH/12” Techline CV, it will need 35 psi to operate properly. If it is from
323ʼ- 369ʼ, it will need 45 psi. Note: We will discuss how to regulate your pressure in the Pressure

Regulating Valve section on page 14.

• Once the zone is laid out, note the pressure you will need somewhere on the design. We will need
this information later to size the Pressure Regulating Valve.

TABLE 2

CENTER FEED GRID LAYOUTS:

• You can increase the length of
laterals by center-feeding the zone.
By doing so, you can have a length
of Techline CV as called out in Table
2 going in each direction, effectively
doubling the maximum lateral
length. This is just like we discussed
with the LITE layout on page 6.

• Where layout flexibility exists,
Center Feed layouts are an
excellent design method.

• They allow for the most even flow of
water through the zone.

• They are an excellent option for
median strips and other large,
homogenous areas.

Techline CV

Center Feed Layout

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BASIC

Exhaust Header

Supply Header

Check longest
lateral agains

t

Table 2 for
maximum
lateral length.

Exhaust Header

Supply Heade

r

Total the combined

length of these

Techline CV laterals

and compare it
against the maximum
lateral length allowed

in Table 2.

Techline fittings
and dripperline

PVC or

Poly Piping

DESIGN

STEPS

(continued)

OTHER GRID LAYOUT CONSIDERATIONS:

• When branching out or joining rows of Techline CV, one of two rules apply:

Rule #1: When branching out Techline CV from the supply header, add up all “branched out”

dripperline and check it against the maximum lateral length listed in Table 2.

Rule #2: When joining laterals from the supply header, check only the longest lateral against the

maximum allowable in Table 2.

Branching Out

Techline CV Laterals

• To reduce the number of glue joints, saddles or insert fittings in a header, transition to Techline CV
and Techline fittings to make up subheaders.

• Make sure to follow the guideline of not exceeding 5 GPM in the “sub-header” zone.

Techline CV Laterals

Joining

Creating Sub-Headers to

Reduce Glue/Saddle Joints

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N E T A F I M T E C H L I N E® C V D E S I G N G U I D E

BASIC

0.26 GPH Dripper 0.9 GPH Dripper

26.40 GPH

17.58 GPH

Not Available

0.44 GPM

0.29 GPM

Not Available

0.4 GPH Dripper

40.OO GPH

26.67 GPH

Not Available

0.67 GPM

0.44 GPM

Not Available

61.00 GPH

41.00 GPH

31.00 GPH

92.00 GPH

61.00 GPH

46.00 GPH

1.53 GPM

1.02 GPM

0.77 GPM

12"

18"

24"

0.6 GPH Dripper

1.02 GPM

0.68 GPM

0.51 GPM

TECHLINE® CV Flow

(per 100 feet)

DRIPPER SPACING

DESIGN

STEPS

(continued)

ZONE WATER REQUIREMENTS:

• Once the Techline CV is laid out, we need to identify total zone flow. This will help determine
mainline, submain as well as supply and exhaust header sizing, valve, filter, and pressure regulator
selection.

• There are two ways to determine the flow in a Techline CV zone.

• Because Techline CV is pressure-compensating, the flow rate per 100' is the same over a wide
pressure range.

• Table 3 shows an easy way to determine total zone flow:

– Add up the amount of Techline CV

(in hundreds of feet) and

– Multiply that figure by the corresponding dripperline GPM to determine zone flow.

Calculating Total Zone Water Demand

• Multiply Total Feet x 12” = Total inches of Techline CV

• Total Inches of Techline CV ÷ Dripper Spacing = Number of Drippers

• Multiply Number of Drippers x Dripper Flow Rate (GPH) = Total GPH Flow

• Total GPH Flow ÷ 60 = Total GPM in the Zone

Example:

Ten 100ʼ rows of Techline CV with Dripper Spacing of 18”, Flow Rate is 0.6 GPH.

100ʼ x 10 = 1,000ʼ

1,000ʼ x 12” = 12,000” 12,000” ÷ 18” = 667 Drippers

667 Drippers x 0.6 GPH = 400 GPH Total Flow

400 GPH ÷ 60 = 6.67 GPM Flow in the Zone

TABLE 3

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BASIC

DESIGN

STEPS

(continued)

NOTE

TL075MA
3/4" Male

Adapter

FITTINGS:

When laying out Techline CV, you will need to use fittings. If you have chosen a GRID layout, you may
need a transition fitting from the supply piping to the Techline CV. Further, you will use Techline CV
fittings to connect the rows of Techline CV to the headers. If you are using a LITE layout, you will also
use a transition fitting from the supply piping, as well as a fitting at the end or midpoint of the zone so
that a flush point can be installed.

Netafim 17mm barbed insert fittings are designed to speed the installation as well as offer you a broad
range of choices, (see page 38).

The barbed end(s) of all Techline CV fittings is raised and sharp. This allows the fitting to be used with
operating pressures up to 50-psi without clamps. If pressures are expected to exceed 50-psi, a clamp
is recommended. Ensure that the clamp is secured over the raised barb.

Fittings are simply pressed into the tubing. No special tools are required. As with all polyethylene pipe,
do not heat the tubing before inserting the fittings. It is not necessary and it can damage the pipe.

STAPLES:

Techline CV staples (TLS6) are used to hold dripperline in place.

While most commonly used when Techline CV is laid on-surface
or under a mulch cover, staples are also valuable when a layout
is being assembled sub-grade before being covered with dirt.

Rule of Thumb: Use a minimum of one staple for every:

• 3 feet of dripperline in sand

• 4 feet of dripperline in loam

• 5 feet of dripperline in clay

Further, use 2 staples “xʼed” over each other with any change-of-direction fittings such as tees, elbows
or crosses.

TL050MA

1/2" Male

Adapter

TLIAPE

TLIAPVC

TLS6

LINE FLUSHING VALVES:

NOTE

Techline CV has a check valve in each dripper designed to hold back a 41/2 foot column of water (2-psi
dripper closing pressure). Therefore, it may not be desirable to use an automatic Line Flushing Valve with
Techline CV, since it could allow water to drain from the dripperline after zone shutdown.

• Line Flushing Valves are used to provide a cleansing action in dripperline each time the zone is turned

on.

• When the zone is turned on, the flush valve begins dumping water into a sump located under it.

• The dumping of water (additional flow) allows the velocity of water inside the dripperline to increase

momentarily helping to clean the inside walls of the tubing.

• This action moves sediments out of the zone and into the sump.

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N E T A F I M T E C H L I N E® C V D E S I G N G U I D E

BASIC

Techline Shut-Off

Valve #TLSOV

(blank tubing may be

attached to outlet)

Techline CV Lateral
(or Exhaust Header

)

Valve Box
(Install Per Specs)

Brick Supports
(Three)

3/4" Gravel Sump

(1 Cubic Foot)

Compression Ring
(Provided)

1"

See Specs

Techline
17mm Tubin

g

Finish Grade

Valve Box

(see specs)

Brick Supports (3)

3/4" Gravel Sump

(1 cubic foot)

Line Flushing

Valve (TLFV-1)

DESIGN

STEPS

(continued)

IF AN AUTOMATIC
LINE FLUSHING VALVE IS
DESIRED:

• It is because the desire to have

a cleansing action outweighs the
desire to hold the water inside
the tubing when the zone is off.

• As such, place a Line Flushing

Valve (one per each 15 GPM
of zone flow) as far away from
the source as possible. This will
typically be somewhere along
the exhaust header in a GRID
layout and at the midpoint of the
tubing in a LITE layout.

• When Center Feed layouts are

used, install at least one Line
Flushing Valve on each exhaust
header.

• Line Flushing Valves should

be buried in a valve box with a
gravel sump adequate to drain
approximately one gallon of
water.

• See Air/Vacuum Relief Valves on

page 13.

Netafim Line Flushing Valve

IF AN AUTOMATIC LINE

FLUSHING VALVE IS

NOT DESIRED:

• It is because holding the
water in the Techline CV is
desired and,

• Procedures have been
established to manually
flush the lines during the
season.

• In this case, Techline
Shut-Off Valves
Figure 8 Line Ends (TLFIG8)
should be located along the
exhaust header, or at the
midpoint of a LITE layout.

(TLSOV) or

Techline CV Manual Line

Flush Valve