Precedure Rubber Lining

(

RL-44-08 REV.0 / of 6

KURIYAMA-OHJI (THAILAND) LTD.

Amata City Industrial Estate,

7/113 Moo 4 Mabyangpom

Pluakdaeng, Rayong 21 140, Thailand

( TEL) + 6638-9s6-206, -208

(FAX)+6628-9s6-207

pROJECT i Bangpain Cogen.ProjectI

KOT JOB No. :

ORDERNO. i

VENDER. NO. i RT--++-OS--------i-

REVISION iOI

SHEET No. :

DATE ;tntencuzotz

Messrs :German-Thai Boiler Engineering Co.,Ltd.

RUB BE R LIIYI]VG PRO CED URE

OF

HARD IVATURAL R(IBBER

FOR

EQUIPME]YT& PIPILYG

TOTAL 6 SHEETS WCOVER

DISTRBUTION

Customer

REV I DATE PAGE DESCRIPTION KURIYAMA-OHJI (THAILAND) LTD.

APPROVAL APPROVED tU till//-'4-- Jdv"l -

CHECKED BY--fle*-r=.-

PREPARED BY

e" et

Office

Factory

TOTAI- 3

(

RL-44-08 REV.0 / of 6

This procedure covers Hard Natural Rubber lining work for equipment & Piping.

1.

)

LINING MATERIAL

Material : Hard Natural Rubber

Thickness :5.0mm (+I5 l-0%)

WORIilNG LOCATIONKURIYAMA- OHJI(THAILAND)

OHJI-HARD E-7 (AUTOCLAVE CURTNG rypE)OHJI-HARD E-Is (EXHAUST STEAM CURING TYPE)

3. LINING APPLICATION PROCEDURE

1) Substrate inspection before liningSubstrate shall be checked for appearance, welded zone and flatness.Corners and welded zone shall chiefly be inspected to confirm that it is proper for lining work.Make sure that the welded zone is free from any pinhole, sharp chamfer and undercut etc.

BlastingA11 surfaces to be lined shall be grid blasted in accordance with ISO 8501-1 Sa 2.5 (SSPC-SP-10) orover to ensure that the surface is clean and free from rusts and scales.

Adhesive coatingAdhesive shall be applied on the substrate evenly.

4) Application of rubber sheetRubber sheet shall be checked appearance on the cutting table.It shall be cut slantwise with using soldering, knife, electric cutter or hand cutter etc.It shall be applied rubber cement.It shall be pressed to steel substrate sufficiently with hand rollers as to leave any an under the sheet.

Rubber Lining (t)

Substrate

2)

3)

OVERLAP BEVEL JOINT

RL-44-08_REV.0 / of 6

5) CuringCuring shall be carried out by exhaust steam in accordance with the curing conditions of Ohji -

standard. (Attached Chart of Autoclave & Exhaust Steam Cure)

4. INSPECTION

1) AppearanceRubber lined surface shall be inspected in visually at bright place with sufficient light, and shall befree from the following defects.(a) Mechanical damages(b) Separation(c) Blister(d) Lack of adhesion(e) Smoothness on flange surface

2) Pinhole testPinhole tester shall be used for the pinhole test. A pole of its secondary side shall be scanned theentire surface of rubber lining since applying the high voltage (shown in Table-l).Whether the pinhole does exist shall be examined by discharging the sparks or sounding abuzzeron the pinhole tester. Any pinhole shall not remain to the products.

If the moist, rust or scrap irons stain the surface of the rubber lining, it may cause suspectedpinhole. Hence, the pinhole test shall be gives on the clean surface.

Since applying excessively high voltage or applying voltage for a long time can cause the rubberto be damaged, it is important to select the designated voltage, and not to apply the voltage at onepoint for a long time.Table-l Fixed voltase of the pinhole test

Types ofPinhole tester

Direct, low frequency current

Checked by Voltmeter

OHJI-HARD E-7of

OHJI-HARD E-l5

Test voltage

3,000V per mmTHICKNESS(Max 15kV)

Notes : The pinhole test shall be completely different from insulation tolerance test.Therefore, inspection with unnecessary high voltage shall not be recommended.

RL-44-08_REV.0 I of 6

3) Hardness testThe inspection shall be given to make sure if the products are properly vulcanized.The test piece for hardness shall be vulcanized with the product.The product and the test sample shall be measured by D type of hardness tester.The actual hardness shall be inspected with test piece at 23"C(+21-2) .

OHJI-HARD E-7 : 75D +71-7

OHJI-HARD E-15 : 70D +10/-10

4) Thickness inspectionThe rubber thickness shall be measured by the use of micro tester, or electromagnetic thicknesstester.

Tolerance : 5.0mm (+15 I -0 %)

5. RBPAIRING

In case that a faulty portion will be found, it shall be repaired as follows.

1) The defects shall be cut off.2) It shall be buffed with grinder.3) It shall be cleaned with solvent.4) It shall be applied adhesive.

5) The repairing rubber sheet shall be applied to the coated surface not to leaveany air underthe sheet.

6) It shall be cured.7) After curing, it shall be inspected again.

Precedure Rubber Lining

Documents

Transcript of Precedure Rubber Lining