method statement phap thi cong/… · web view · 2018-03-124.1.9. supports insulation work will...

THE METHOD STATEMENT OF

MECHANICAL

HANGER AND SUPPORT

INSTALLATION

Table of contents

1. Gross References .................................................................Page 3

2. Scope of works......................................................................Page 3

3. Flow of Works Chart..............................................................Page 4

4. Methodology......................................................................Page 5-27

5. Tools and Equipment.............................................................Page28

6. Safety Measures...................................................................8

7. Appendices...........................................................................Page 28

8. Painting Safety Fire

pipe……………………………………………………………………………………………

……Page 29

Page 2

1.Gross References

1.1 General: Refer to the general Requirements worksection

Refer to the following worksection:Mechanical general requirements, Fire protection system, hydranlic system, air

handling uint and ventilation system.1.2 Material:

Material for Hanger and support following the standards on specification Approved type by Engineer To describe mechanical works associated with install hanger and support of mechanical system to

ensure compliance with contract requirements, drawings and technical specification. The design of the

pipe work installation shall be tested and certify strictly in accordance with the requirement specification,

2. Scope of Works

Scope of works install hangers and supports of Mechanical System including the Duct

works system, Piping fire protection and Hydrandlic system. The scope of work for this method

statement shall include all the Mechanical system.

3. Flow of Works (Flow chart):

Shop drawings (Approved)

Material Approved

Determine pipe as per approved location & level

Marking

Not approved

Engineer ‘s inspection

Proceed

Approved

In-house Inspection

Installation of pipe

Define position of support

Approved

Not approved

Approved

4. Methodology

4.1. General4.1.1. The size of Hangers and supports shall be in compliance with the contract specification,

documents, and approved shop drawings.

4.1.2 Hangers and supports of mechanical system shall be fabricated at factory from the approved and galvanized steel sheet roll.

4.1.3 To ensure that all Hangers and supports material are fabricated form the approved, worker

Shall take photo picture on the approved material for record, before starting any fabrication process.When the finished parts delivery to site, the Engineer’s shall check the quality and material

used, by the Q/C labels together with the evidence of the photo picture or refer to shop drawing , on thematerial been used in the fabrication.

4.1.4 Only the site engineer’s final approved Hangers and supports shall be used for the site installation works.

4.1.5. Various hanger systems and components for system shall be used and shall be Coordinated with the ceiling work at the Contractor option with the approval by the Mechanical engineer.

4.1.6 All flanged joints shall be provided with suitable gasket as approved type by the Engineer.

4.1.7 Supports shall be attached to every system using screws or bolt to prevent slippage and noise.

4.1.8.Wall or overhead supports shall be anchored to structure using bolts of suitable type and adequate size or other methods suitable for conditions or materials encountered, only as approved by the Engineer.

4.1.9. Supports insulation work will be mentioned on method statement for mechanical system insulation work.

4.2. Hangers and Supports for duck work systems

4.2.1 Supports and hangers shall be L-type formed steel angles, shall be as shown in Table 1

The vibration isolation rod hanger for fans shall be indicated on shop drawings.

Table 1 Hangers and Supports Schedule ( Refer to AS 4254)

Duct Size

Largest

Dimension

(mm)

Size of L-type

formed steel

angle

(minimum)

(mm)

Hanger rods

diameter

(minimum)

(mm)

Hanger

Maximum

spacing for

Flange Joint

(mm)

Hanger

Maximum

spacing for

TDC Joint

(mm)

Up to 900 30 x 30 x 3 8mm 3,000mm 1500mm

901 to 1600 40 x 40 x 3 10mm 3,000mm 1500mm

1601 to 2200 40 x 40 x 3 12mm 2,400mm -

Over 2,200 50 x 50 x 3 12mm 2,400mm -

Figure 1: Section of Hangers and Supports

(Detail refer to drawing SRF-DT-500)Note: a) Hangers and supports details please refer to approved shop drawings.

Figure 2 Details of Hangers and Supports of Duct work for Riser

(Detail refer to Table HS.5 of MOS hanger support)

(SEE TO FILE AUTOCAD)

4.2.2. Fix Support

4.2.2.1. Check length of duct round and weight according to Table 12-1,12-2.

4.2.2. According to Table 3, select the Steel angle and Anchor bolt. Steel angle must be fabricated at

factory.

4.2.3. Fix support must be fixed to slab or beam.

4.2.2.4. Spacing of Fix support by steel angle shall be 1500mm and below, or refer to shop drawing

approved.

Figure 7: Section of Fix support

(Detail refer to table HS.5))

Note: Fix supports details please refer to approved shop drawings.

Table. 2 Size of Steel Angle and Anchor Bolt

(refer to AS 4254)

Steel angle length - L Steel angle Size(minimum)Anchor Bolt size Slab (mm)

Up to 1000 L-30×30×2.5 M×8Up to 1600 L-50×50×3.0 M×10Up to 2200 L-50×50×4.0 M×12Over 2200 L-50×50×5 M×12

Note: Fix supports details please refer to approved shop drawings. 4.2.3 Plenum Chamber

Plenum Chamber Thickness:

- Thickness for galvanized steel sheet shall be as shown in Shop drawing approved

4.2.3 Reinforcing

- Requirements for Size of L-type formed steel angle reinforcing shall be as shown in Table 4.

Duct including insulation

Anchor bolt (Approved type by the engineer)L-type formed steel angle

Beam

Table 4. Size of L-type formed steel angle Reinforcing

Notes

- Installation details shall be indicated on shop drawings.

- Details of plenum chamber shall be indicated on the shop drawings.

Largest Dimension of

Plenum Chamber (mm)

Size of L-type formed

steel angle

Size (minimum)

(mm)

Maximum Spacing

(mm)

Up to 1000 L-30×30×2.5 1500

Up to 1600 L-50×50×3.0 1500

Up to 2200 L-50×50×4.0 1500

Over 2200 L-50×50×5 1500

4.3. Pipe Hangers and support for system

- Piping or equipment supported by wire, plumber’s tape, rope or other means or arrangements shall not

be permitted.

- Pipe or equipment supported by valves or other line accessories shall not be permitted.

a) Vertical piping shall be supported as follows:

i) Risers: Steel angle support to rest at least on refer to shop drawing approved

ii) Copper pipe: Steel angle support with rubber and refer to shop

b) Horizontal piping shall be supported as follows:

Pipes shall be attached to or supported from structure using hangers and devices as specified or

approved.

c) Hanger and Fix support spacing shall be as the following Table 5.

Table 5: Hanger and Fix support spacing

15 20 25 32 40 50 65 80 100 125 150 200 250 300

Hang Spacing

Carbon Steel Pipe

2.0 m or less 3.0 m or less

Polyvinyl chloride pipe

1.5 m or less 1.2 m or less

Copper pipe 1.5 m or less 1.5 m or less

Fix Support Spacing

Carbon Steel Pipe

___ Span by span or less

1.5m or Show on Shop Drawing

Polyvinyl chloride pipe

___ Span by span or less

Span by span or less

1.5m or Show on Shop 1.5m or Drawing

Copper pipe ___ Span by span

or lessSpan by span or

less1.5m or Show on Shop

Drawing

d) Low temperature pipe insulation shall be required for refrigerant lines and chilled water lines at

points of support between pipe and hanger using rebar sheet or wood approved.

e) Copper pipe isolation shall be required for each point of contact with hangers or other ferrous

materials.

f) Hanger rods

i) Hanger rod size shall be as the following Table 6:

Table 6: Hanger rod size (Item B of Spection)Supported pipe (mm) Rod diameter (mm)

<20 0620 to <100 10100 to 120 12

DiameterType

>120 to 275 16>275 to 325 20

Over 325 24

Table 10 U bolt Size (Spection)

Diameter Pipe U bolt Size

16mm – 34mm 6mm

42mm – 90mm 8mm

Over 90mm 10mm

From 150 - 250 25x2mm

4.4.3. Additional Support

At changes of direction in either vertical or horizontal and point near the valve, additional support

shall be provided. However it may be omitted when coincidental with required standard spacing

location.

Figure 9. Additional support

4.4.4. Fix Support

1. Check the pipe weight, number and support spacing (Table 5).

2. According to Table 9, select the Steel angle and Anchor bolt.

3. The method of fixing for Insulated pipe is in accordance with Section8.8.

Support

Valve size is Less than 100mm

Support near valve

600mm and above

Support near branch

45°

Valve size is 100mm and above

600mm and above

300ｍｍ or below

Support near branch

Support near bent

Support near bent

Support near bent

Support

Support

Support

Support

Support

Support

300ｍｍ or below300ｍｍ or below

Support

Figure 10 : Example for connect pipe over 65mm (for Chiller water pipe)

Table 9 Size of Steel Angle and Anchor Bolt

Note: Steel angle and bolts shall be indicated on shop drawings.

Weight (kg)

Steel Angle Length Size of Steel Angle and Anchor Bolt

L HSteel angle

Size(minimum)Anchor Bolt Size(minimum)

Slab Wall

60500

1000 L-50×50×5.5 M10×30×2 M10×30×21500 L-63×63×5.5 M10×30×2 -

10001000 L-63×63×5.5 M10×30×2 M10×30×21500 L-63×63×5.5 M10×30×4 -

120

5001000 L-70×70×6.5 M10×30×4 M10×30×21500 U120×48×4 M10×30×4 -

10001000 L-75×75×5.5 M10×30×4 M10×30×21500 U150×48×4 M24×30×4 -

2401000

1000

U120×48×4

M10×30×4 M10×30×21500 M10×30×4 -

15001000 M10×30×4 M10×30×21500 M10×30×4 -

3601000

1000

U150×48×4

M10×30×4 M10×30×21500 M10×30×4 -

15001000 M10×30×4 M10×30×21500 M24×30×4 -

4.4.5 Setting of Floor Drain and Clean out

Setting of Floor Drain and Clean out shall be followed as under Figures.

(Fire stopping will be supply late)Figure 12 Setting of Clean out Type A

Cap

SlabConcrete

PVC pipeSteel panel

Cut pipeFinishing work (Architectural work)

Clean out (COA)

Process 1)1. Install pipe and steel

panel.2. Fill concrete.

Process 2)1. Finishing work by

Architectural work.2. Cut pipe.

Process 3)Install COA ( upper part ).

(Fire stopping will be supply late)Figure 15 Detail of pipe penetration for water proof

Cap

SlabConcrete

PVC pipeSteel panel

Water proofing(Architectural work)

Cut pipe

Finishing work (Architectural work)

Connect Sanitary Fixtures

Process 1)1. Install pipe and steel panel.2. Fill concrete. Make slope for water proofing.3. Water proofing ( Architectural work )

Process 2)1. Finishing work by Architectural

work.2. Cut pipe.

Process 3)1. Install Equipment. 2. Apply sealing compound.

Sealing compound

4.4.6.Methodologies:

- For all sprinkler piping installation either wall or ceiling area.

- Work will be executed by fixing anchor bolt into concrete structure or brick wall with approved

bracket support and dimension according to approved shop drawing

- All brackets supports shall be factory-fabricated and hot dipped galvanized to JIS H8641 Standard

prior to delivery to site for installation.

- Deliver pipes and fittings to designated area of site work. Check and ensure sufficient quantity for

area installation.

- All supports shall be fabricated at workshop factory shall be approved type based on sample

submitted and approved by the Engineer.

- Installed supports will be checked by the Engineer.

- All bolt and nuts accessories shall be approved brand/ types by the Engineer based on submission

and approved.

- Locate position of pipe installation as according to shop drawing.

- Siamese fire department connection shall be as per approved drawing location easily be

approached by fire engines for emergency fire fitting. Type of connection shall be compatible

with hose fitting used by the local fire department and based on Vietnamese standard.

a) Pipe shaft area :

- Carry pipe by manual labor to location. Chain block may be used to lift bigger pipe for

installation.

b) On ceiling area :

- Carry pipe to designated area of installation: for bigger pipe, chain block shall be used to hoist

pipe to ceiling area.

- Pipe shall be cleaned before installation.

- Pipe shall be adjusted to fix location as according to approved shop drawing indicated and

according to the construction schedule.

- Mark and determine the location of pipe support.

- Installed pipe shall be pressure tested and inspected by the Engineer for approval.

- Shall be cleaned system before pressure test / leak test.

4.4.7 Marking and cutting.

- All pipes size diameter 150mm and smaller shall be cut by electric powered, circular machine

with abrasive wheel. Metallic wheel cutters shall not be permitted.

- For pipes with outside diameter 150mm and greater shall be cut by Oxyacetylene torch.

- After cutting, edges of pipe shall be grinded forming an angle of 300. Refer to Figure 10

4.4.8 Cut a hole to join smaller pipe:

For steel pipe connect to steel pipe that is two times smaller than diameter of main pipe

- Cut a hole on main pipe by using oxyacetylene torch to create a hole.

- Use grinder machine to smoothen the edges and burrs of the cut hole before joining the main pipe

and the smaller pipe together forming a 900C

- Seam of joining shall be welded in three passes.

- During work not in progress, the opening of hole shall be temporary capped to prevent entry of

foreign object.

- Take out galvanize for Fire protection

- For flange weld, spot weld at 1 point, then connect flange surface perpendicular to pipe and spot

weld at 3-4 points prior to full welding and after that take down floor weld complete for Fire

protection pipe. Note that seam of weld in outside face shall not be out off flange face.

- Remove water, oil and paint off completed weld.

- Weld at 3-4 points on seam, then roll pipe to continue welding from up and down.

- Completed weld shall be clean by using wire brush and prime paint.

Inspection of weld. Refer to Figure 10

- Weld seam shall be checked visually.

- Weld joint will be thicker than edge of pipe maximum 3mm.

- Weld defects shall be remoed and repaired under the Engineer’s supervision.

a. Screwed threaded connection.

- Pipe will be threaded by using the threading machine JIS B0203 Standard with automatic thread

defining dimension.

- Add suitable oil onto the cutting part or filling oil regularly onto cutting part of threading

machine. When oil changes color due to mixing with water, change new oil.

- Change threading teeth when pitches are not threading in regular manner due to wear and tear.

- Check length and surface of pitches visually and adjust selection of threading range by hand.

- Remove oil and dust on pitches, inside and outside pipe prior to start threading.

b. Tightening threaded pipe and fitting.

- Apply teflon sealing tape around the threaded pipe.

- Screw pipe and fitting by hand, and then use pipe wrench to tighten slowly till pipe and fitting

firmly tighten.

- After tighten screw connection, cover odd pitches with primer paint and mark of pipe wrench.

- Pressure test shall be carried out after area pipe work completed and jointed area paint dry up.

d. Sprinkler heads installation and coverage.

- A sprinkler head shall be installed at every part of a ceiling divided by beam, etc. projected 0.4m

above from the surface of installation for the said heads. However, this shall not apply in case the

mutual central distance of the said beams does not exceed 1.8m or less.

- In case there should be 1.2 m above of width and length for air duct, shelf etc, a sprinkler head

shall be installed at the bottom surface of the said duct etc.

- A distance between the deflector of sprinkler heads and the surface of installation for the said

heads, shall be 0.3m below.

- Sprinkler heads shall be so installed that the spindle thereof is perpendicular to the surface to

which the said head is fitted.

- Nothing shall be either installed or placed in the section within the distance of 0.45 m from the

deflector of a sprinkler head, and 0.3m below of horizontal direction, or installation refer to Spec

4.4.9 Support installation

a. For ceiling support. Refer to Section on ceiling (file Autocad)

- Drill a hole and insert anchor bolt into concrete structure according to construction working

schedule and approved shop-drawing.

- Fix threaded rod support into insert anchor bolt and fix C-channel into location before laying pipe

onto the bracket support.

- Check the level of bracket support to ensure the pipe work have been done as according to the

approved shop drawings and location.

Support hanger sizes on ceiling

Supported pipe (mm) Rod diameter (mm)

50 and smaller 08

50-100 10

125 through 200 16

250 and larger 24

b. For support on wall and pipe shaft. Refer to Figure Riser (file AutoCad)

- Mark sure & fabricate support and then Galvanize for level B3, B2, B1, Roof, Riser

- Check support by plump-line to ensure bracket support are in a vertical straight line

- Fix bracket support onto wall and fastened with nuts to get support in position.

- Mark the location of pipe support as according to approved shop drawing.

- Drive a hole into wall of concrete structure or brick wall.

- Drill an anchor bolt into drilled hole.

- Fix bracket support onto wall and fastened with nuts to get support in position.

4.4.10 Prime paint and identification of pipe

- Completed pipe will be prime paint by the approved color code.

- Symbol of identification of pipe will be suitable to diameter of pipe.

- Direction of arrow denote the way of water flow

Schedule of lettering sizes

(or refer to spection)Outside diameter of pipe or

covering (mm)Size of stencil

letter (mm)Minimum length of flow

arrow (mm)20 to 40 incl. 12 6050 to 100 incl. 25 100125 to 175 incl. 50 125200 and larger 75 150

Schedule of hanger support spacing

Location

Pipe

20mm diameter or

less

25mm to 40mm

diameter

50mm to 80mm

diameter

100mm diameter or

moreSteel pipe 2.0mm 2.0mm 2.0mm 3.0mm

5 Machinery & Tools

- Power hacksaw

- Circular cutting machine with abrasive wheel

- Pipe clamp

- Plump-line

- Power drill.

- Chain block.

- Threading machine.

- Scaffolding

- Pipe wrench

- Spanner

- Hammer

- Water level ruler

6. Safety Measures

- Temporary barricade and warning sign shall be set up at area of site work

- Any worker works at the height of 2m and above shall wear safety belt.

- Workers shall be trained about safety condition.

- Machineries, equipments and staging should be inspected by safety supervisor prior to work

- A safety forms signed by workers and briefing before work will be provided to control the safety

working condition (forms enclosed).

7. Appendix

- Leaking test record.

- Available for Inspection (AFI)

- Inspection Record (IR)

8. Paniting sefety fire pipe

Step 1: Carry pipe to location area installation, properti floor at work area to be done.

Step 2: Clean pipe

Step 3: Painting Iron-Mould safety and (Break-Zinc if need) by Grey color

Step 4: Painting one undercoat by Red color

Step 5: Painting complete safety by Red color – 1ST

Step 6: Painting complete safety by Red color – 2ND

Step 7: Check after instal finish

method statement phap thi cong/… · web view · 2018-03-124.1.9. supports insulation work will...

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