Rubber Lining Procedure

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RUBBER LINING FOR ABRASION AND CORROSION SERVICE

PROJECT

CLIENT

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Division

Page : 1 / 1 CONTENTS

No.

Description

Doc. Nr.

Rev. Nr

1. RL-01/01

0

2. Introduction

RL-01/02

0

3 Reference Standards

RL-01/03

0

4 Design of Pipes and Structures

RL-01/04

0

5 Lining Materials

RL-01/05

0

6

• _•

Technical Data sheet for rubber material

Technical Data sheet for Priming and Bonding

solution

RL-08/01 to 04

0

7 Rubber Lining – Flow Chart

RL-09/04.01

0

8 Rubber lining Process Control

RL-01/06

0

9 Operation Manual – Pre Inspection of Lining

_Components

RL 9.5

0

10 Operation Manual – Lining Material Selection

RL 9.6

0

11 Operation Manual – Surface Preparation

RL 9.10

0

12 Operation Manual – Adhesive Coating

RL 9.11

0

13 Operation Manual – Lining

RL 9.12

0

14 Operation Manual – Curing

RL 9.13

0

15 Operation Manual – Repair of Rubber Linings

RL 9.14

0

16 Operation Manual – Final Inspection and Testing

RL 9.15

0

17 Operation Manual - Handling, Storage, Packaging

and Delivery of rubber lined products

RL 9.18

0

18 Quality Plan Rubber Lining

PL-20-01

0

19 Quality Control Formats

A. Pre Inspection Report

F-20-01

0 B. Inspection Report - Blasting

F–20-02

0 C. Inspection Report – Adhesive Coating

F-20-03

0 D. Material Inspection Report

F-20-04

0 E. Inspection Report - Lining

F-20-04

0 F. Curing Sheet - Lining

F-20-05

0 G. Final Inspection Report

F-20-06

0 H. Material Test Report

F-28-02

0

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Date :

Rubber Products

Division

RUBBER LINING FOR CORROSION AND ABRASION SERVICE Code : RL-01/01

Issue : 1 Revision : 0 Page : 1 / 2 RUBBER LINING CONTENTS

1.0 Scope

This RL-01 specifies requirements, gives recommendations for the application,

qualification testing, production testing, inspection and transportation of rubber lined

process equipment, piping and flanges.

This RL-01 is applicable to vulcanized rubber lined process equipment, piping and

structures.

2.0 Procedure

2.1 Receiving the structure to the rubber lined at our works in Jebel Ali (UAE).

2.2 Inspection of areas to be lined for the suitability and feasibility of carrying out

rubber lining works.

2.3 Acceptance of the design of the metal equipment to be lined shall be in

accordance with BS 6374: Part 5: Clause 2.2. Areas found otherwise shall be

rejected from being lined and proper, corrective actions shall be taken by the client

or if approved at our works.

2.4 Acceptance of the fabrication of the metal equipment to be lined shall be in

accordance with BS 6374: Part 5: Clause 2.3. Areas found otherwise shall be

rejected from being lined and proper, corrective actions shall be taken by the client

or if approved at our works.

2.5 Control plan for rubber-lined equipment is as per PL-20-01.

2.6 Upon acceptance of the metal equipment to be lined, all rubber lining procedures,

testing and acceptance, criteria shall be in accordance with related ASTM, BS,

SIS, and etc. reference standard as per Operation Manual RL 9.5.

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Rubber Products Division Issue : 1 Revision : 0 Page : 2 / 2 RUBBER LINING CONTENTS

2.8 The areas to be lined shall be grit blasted to SA 3.0 degree of cleanliness in

accordance with SIS 005 590. Grit blasting of the surfaces shall be carried out as

per Operation Manual RL 9.10.

2.9 The grit blasted areas shall be coated with appropriate primer, elastomer bonding

agent and rubber solutions and then rubber lined as detailed in Operation Manual

RL 9.11 and RL 9.12.

2.10 Rubber lined areas shall be tested and accepted in accordance with BS 903 in our

Operation Manual RL 9.15.

2.11 The rubber-lined equipment shall be collected from our works as detailed in

Operation Manual RL 9.18.

3.0 Distribution

This manual RL-01 is confined to the companies and the contractors and

manufacturers/suppliers nominated by them.

This manual RL-01 is intended for use in oil refineries, chemical plants, desalination

plants, industrial plants etc where applicable.

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Division

RUBBER LINING FOR CORROSION AND ABRASION SERVICE

Code : RL-01/03 Issue : 1 Revision : 0 Page : 1 / 1

REFERENCE STANDARDS

The following Standards, latest editions are normally followed in the execution of the works.

Specific standards related to the rubber compound to be applied are to be followed, wherever

applicable. In addition to the above standards, any other standards specified by the client shall

be obtained and met after review compliance, wherever applicable.

ISO 9002 - 1994

Quality Systems Part 2

ISO 83.060

Methods of testing unvulcanised rubber

ISO 37

Tensile Properties

ISO 48

Rubber Hardness IRHD

ISO 188

Accelerated ageing and heat resistance test

ISO 815

Compression Set

ISO 1431 Part 1

Resistance to Ozone Cracking

ISO 1817

Determination of the effects of liquids

ISO 7619

Rubber – Determination of indentation hardness by

means of pocket hardness meters

ASTM 09.01

Annual book of ASTM standards - Rubber, Natural

Rubber and Synthetic - General Test Methods; Carbon Black

ASTM 09.02

Annual book of ASTM standards - Rubber products, Industrial –

Specifications and related test methods ; Gaskets; Tires

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Rubber Products Division 01/04 Issue : 1 Revision : 0 Page : 1 / 1 RUBBER LINING

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Division

RUBBER LINING FOR CORROSION AND ABRASION SERVICE Code : RL-_01/05 Issue : 1 Revision : 0 Page : 1 / 1 RUBBER LINING LINING MATERIALS

1.0 Material Selection

Material selection is determined by:

• Service condition - Application, Pressure, Temperature, type of medium, medium

concentration etc.

• Manufacturing method.

• Design.

As per Operation Manual RL 9.6

2.0 Lining Materials

2.1 The rubber material to be used for lining is determined for the specific application

or in accordance with client’s specifications. The client prior to use approves

technical data sheets of the material to be used.

2.2 Appropriate primer material compatible with the rubber material to be used.

2.3 Appropriate elastomer bonding solution compatible with the rubber material and

primer to be used.

2.4 Appropriate rubber solutions compatible with the rubber material, primer and

bonding solution to be used for holding the rubber sheets in position while lining.

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RUBBER LINING MATERIAL DATA SHEET

POLYMER: NEOPRENE RUBBER CODE: CR65A

SL No Physical properties Test Method Units Specification

1 Specific Gravity - 1.45 – 1.55

2 Hardness ISO 7619 SHORE ‘A’ 60 – 70

3 Tensile Strength ISO 37 Kg/ Cm 2 _{Min. 80}

4 Elongation at Break ISO 37 % Min. 300

5

After ageing properties At 100˚ C for 72 Hrs. Change in Hardness Change in Tensile Change in E.B. ISO 188 ± 10 Max. - 20 Max. - 30 6 Compression Set_{At 100 ˚C for 24 Hrs.} ISO 815 % 30 Max.

7 Water AbsorptionAt 70 ˚C for 7 days.

Change in Volume ISO 1817 % 5 Max.

8 Spark resistance Spark Tester - No Spark

9

General Characteristics:

• Excellent resistance to ageing and weather. • Excellent resistance to Ozone.

• Excellent resistance to Flame. • Good resistance to Chemicals.

• Good resistance to mineral Oils, grease, many refrigerants water and crude oils. • Good resistance to erosion at high impingement angles. (Bends, Tees etc.) Colour - Black

Prepared By: Approved By: _Date:

The information provided is believed to be accurate but the company disclaims any responsibility for consequences arising from usage of material, in that the conditions of usage are beyond the company’s control

RL-08-01

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Issue No: 1 Rev No: 0 Date: 02.04.2003

RUBBER LINING MATERIAL DATA SHEET

POLYMER: NITRILE RUBBER CODE: NB70A

5

After ageing properties At 100˚ C for 72 Hrs. Change in Hardness Change in Tensile Change in E.B. ISO 188 ± 10 Max. - 20 Max. - 30 6 Compression Set_{At 100 ˚C for 24 Hrs.} ISO 815 % 30 Max.

7

Oil resistance

At 100 ˚C for 7 days in ASTM 3 Oil.

Change in Volume

ISO 1817 % ± 5 Max.

9

General Characteristics :

• Excellent resistance to Chemicals.

• Excellent resistance to mineral Oils, grease, many refrigerants water and crude oils. Colour - Black

Prepared By:

Approved By:

Date:

RL-08-02

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RUBBER LINING MATERIAL DATA SHEET

POLYMER: NATURAL RUBBER CODE: NR70D

5

After ageing properties At 100˚ C for 72 Hrs. Change in Hardness Change in Tensile Change in E.B.

ISO 188 Shore ‘A’ % %

± 10 Max. - 20

Max. - 30 6 Compression Set_{At 100 ˚C for 24 Hrs.} ISO 815 % 30 Max.

7

Oil resistance

At 100 ˚C for 7 days in ASTM 3 Oil.

Change in Volume

ISO 1817 % ± 5 Max.

9

• Good resistance to Acid. • Good resistance to Water. • Good resistance to Tear. Colour - Black

Prepared By:

Approved By: Date:

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RUBBER LINING MATERIAL DATA SHEET

POLYMER: EBONITE - NATURAL RUBBER CODE: EB70A

1 Specific Gravity - 1.50 ± 0.05

2 Hardness ISO 7619 SHORE ‘D’ Min. 60

4 Service Temperature - - - 20 ºC to + 100 ºC

5

• Good resistance to Acid (32 % HCl).

•

Good resistance to Water containing H2S and very high alkalinity.

• Very good resistance to weather and Ozone. • Good resistance to Tear.

Prepared By:

Approved By : Date :

The information provided is believed to be accurate but the company disclaims any responsibility for consequences arising from usage of material, in that the conditions of usage are beyond the company’s control.

RL-08-04

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Rubber Products Division Issue : 1 Revision : 0 Page : 1 / 5 RUBBER LINING

RUBBER LINING PROCESS CONTROL

RECEIVING INSPECTION

1.1 Based on Operation Manual RL 9.5

,

Foreman and Stores in Charge to receive

customer supplied products and verify the products for transit damage and

conformance to the specified requirements. J.O. Number shall be marked on

accepted products. Acceptance of the design of the metal equipment to be lined

shall be in accordance with BS 6347: Part V: Clause 2.3. Any minor grinding is to

be done on the customer supplied products against the requirement for lining is

carried out after getting the consent of the customer.

Responsibility: Foreman/ Stores in charge

SURFACE PREPARATION

1.2 Grit blast areas to be rubber lined to SA 3.0. The surface amplitude shall be in the

range of 75 to 100 microns clean blasted areas to remove all dust and foreign

particles by compressed air. Inspection to be carried out in accordance with

Operations Manual RL 9.10. Remove any visible oil or grease prior to blasting.

Responsibility: Operator

1.3 Apply Primer (25 microns minimum) within 4 hours of grit blasting by spraying or

by brush application. Allow primer to dry for 15 to 30 minutes depending on the

weather condition.

Responsibility: Operator.

1.4 Apply cover coat (40 microns minimum) by hand brushing. Allow 30 to 40 minutes

drying time.

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Division

RUBBER LINING FOR CORROSION AND ABRASION SERVICE Code : RL-01/06 Issue : 1

Revision : 0 Page : 2 / 5 RUBBER LINING

RUBBER LINING PROCESS CONTROL

LAYING OF RUBBER SHEETS

1.5 Based on Operation Manual RL 9.12, Lab in Charge & Foreman will select the

suitable rubber compound required in consultation with FM/ QAM

Responsibility: Lab in Charge/ Foreman

1.6 Foreman will inform the Mill Operator the required weight for mixing. Lab in

Charge will check the physical properties of the compound and give clearance

certificate for further process.

Responsibility: Lab in Charge/ Operator

1.7 Rubber used for lining may be a portion of any final batch or mix of one or more

final batches based on the quantity required to complete on job card. Final lot

numbers and weight consumed shall be indicated on the job card.

Responsibility: Foreman.

1.8 Use the Calendered or Milled sheet for rubber lining and select the type of joint as

indicated below. The Foreman decides this. The rubber thickness is as per the

customer’s specification.

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Division

Revision : 0 Page : 3 / 5 RUBBER LINING PROCESS CONTROL

1.9 Cut the sheets carefully with a knife and place it on a white fabric spread on a

table. Roll the compound strapped in textile in such a way that the compound does

not stick together. Transfer the roll to the desired table for lining.

Responsibility: Operator

1.10 Apply two coats of Rubber Solution by hand brush to ensure proper holding of the

rubber in position. Allow 5 to 15 minutes per coat as drying time depending on

weather conditions.

Responsibility: Operator.

1.11 Apply sheeted uncured rubber by hand application. Stitch properly with special

tools (wheels) to ensure that no air is trapped between the body and the sheets.

Methods of rubber lining flanges can be any one method described below:

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RL -9.4.1

FLOW CHART – RUBBER LINING

DEFECT

OK

CUSTOMER

PROPERTY

PR

EL

IM

INA

RY

IO

CT

SPE

IN

N

REMOVAL OF

RUBBER

BLASTING

ADHESIVE

SYSTEM

LINING

INSPECTION

CURING

FINAL

INSPECTION

MIXING

AGEING ROOM

EXTRUDER /

CALENDER

SHEET

RAW

MATERIALS

LAB

TESTINGG

REPAIR

DELIVERY

REPAIR

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Revision : 0 Page : 4 / 5 RUBBER LINING PROCESS CONTROL

The Foreman according to the nature of the project requirement decides the type.

Linings of pipes are also done by the same method and larger diameter pipe into

which a person can crawl and do the lining. Rubber lining of a small diameter pipe

is done by making a tube and pulling the tube through the pipes using a protective

cloth. Remove the cloth from another end and adhere the rubber tube of the walls

of the pipe either by using compressed air or by using rubber bowls.

Before curing, the Pinholes are detected by the holiday detection (1.5 KV/mm or

as the voltage agreed in the contract and as per the Control Plan as agreed for the

project) are marked and such areas are repaired by filling with rubber. Deflash

excess rubber wherever to be trimmed and wherever detected, loose bonding

shall be stitched properly.

Responsibility: QC Inspector/Operator.

CURING

1.12 Complete rubber lining of the whole structure and carry out the curing process at 0

kg/cm

2

_{pressure for open steam curing and up to 5 kg/cm}

2

_{pressure for autoclave}

curing as indicated on the job card. Water curing and chemical curing are also

carried out. The Production Manager decides curing technique for the particular

job.

Responsibility: Operator

1.13 Steam temperature, pressure and curing duration is determined depending on the

size and shape of the product, thickness of lining and recommendations in the Job

Order Card F-08-04 and as per Operation Manual RL 9.13 for determining the

curing time.

1.14 After the minimum stipulated time of curing is completed, stop steam supply and

remove the products.

Responsibility: Operator

1.15 Remove excess rubber, overflows, etc. and repair the areas, if any.

Responsibility: Operator

1.16 Inform QC after finishing for inspection.

Responsibility: Operator

1.17 Operators are trained in accordance with the Operation Manual RL 9.12.

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Division

OPERATION MANUAL

Code : RL 9.5

Issue : 1 Revision : 0 Page :

1 / 1

RUBBER LINING

PRE INSPECTION OF LINING COMPONENTS

Purpose: Scope: Responsibility: Definition: Procedure: Related Documents: References: Distribution:

To ensure that components, materials and products given to the company as a part of the job orders is suitable for Rubber Lining.

All Rubber Lining Components.

Factory Manager (FM) / Production Manager (PRM) / Stores In charge (SI) / Production Foreman (PF)

Nil.

1. Stores In Charge in co-ordination with PF will check and verify all components and items on receipt against delivery documents for type, quantity and visually examines for any damages etc. and enter in the Customer Property Register.

(RG-25-01)

2. Customer property is identified by marking the customer's name or name code on the product and fixing a tag where marking is not practical. ( L-25-01)

3. Foreman in co ordination with QCO will verify the suitability of the components for lining

(Pre Inspection Report F-20-01)

4. Any discrepancies are reported to the PRM who will inform the FM / SM for notifying the customer.

5. Any mechanical damage will be rectified after Customer’s approval. 6. The type and quantity of the items received is informed to the SPCO.

7. The components, items and materials are handled using appropriate methods to avoid damage or lost throughout the production process.

8. Any damage or loss is reported immediately to the FM for notifying the customer and a note is made on the job order of such damage or loss.

9. Customer drawings and specification sheets are filed in the respective customer files as described under Control of Documents. QSP 02

Job Order Card F-08-04 Customer Property Register RG-25-01 Pre Inspection Report F-25-01 Customer Property Identification Tag L-25-01. Document Control QSP 02 FM/ QAM/ PRM/ SI Prepared by: QA/QC Manager Date: Approved By Executive Director Date:

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Page : 1

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LINING MATERIAL SELECTION

Prepared By QA/ QC Manager Date: Approved By Executive Director Date: Purpose: Scope: Responsibility: Definitions: Procedure: Related Documents: Distribution:

To ensure that the material selected for the lining is correct and conforms to the specified requirement.

All Lining materials. FM/ QAM/ SM / LIC Nil.

1.0 The material suitable for lining the particular item is identified by the FM/ QAM / SM taking into consideration the,

1.1 Service condition, type of medium and its concentration, temperature of use etc.

1.2 Lining method. 1.3 Design

2.0 Suitable material will be recommended by QAM/ LIC by analyzing existing rubber Lining.

3.0 The compound to be used is written in the JOC. Job Order Card F-08-04

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Rubber Products Division

OPERATION MANUAL

9.10 Issue : 1 Revision : 0 Page : 1

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RUBBER LINING

SURFACE PREPARATION

Purpose: Scope: Responsibility: Definition: Procedure: Related Document: Distribution:

To establish procedures which will generate a steel substrate suitable for lining.

This procedure will cover preparation and inspection of fabricated components, cleaning of the steel and blasting for lining

Production Manager (PRM) / Production Foreman (PF)

Blasting - Removal of rust, scale or any foreign material by use of abrasives propelled through a nozzle.

1. The Welding should be continuous and the steel surface shall be ground such that there are no sharp corners, to achieve a radius 3 – 5 mm maximum.

2. Any surface defects particularly surface laminations, scars, which are likely to affect the linings, shall be removed by dressing. All welds are to be inspected and repaired prior to the blasting.

3. Cuttings / Heat application produces hard zones on the edges of plates, flanges, grinding is to be done in these areas. i.e. Where normal blasting is insufficient to obtain the required finish.

4. All welding flux and waste must be removed and welds rounded to obtain a smooth radius.

5. In case the item has damaged rubber linings the lining is removed first by either chipping / de-bonding application of heat on the external surface as to de-bond the rubber inside.

6. All metal surfaces to be blasted shall be free from oil, grease or any other foreign matters. Cleaning of the surface should be done by washing with a solvent.

7. Blasting media must be clean, new material or properly separated to remove fines to ensure a proper profile and clean surface.

8.

The temperature of the substrate shall be minimum 3-5 ˚ C above the dew point during surface preparation. The relative humidity shall not exceed 85%. This shall be monitored at the beginning and every four hours during continuous blasting.

9.

After the blasting, the grit particles shall be removed from the steel by brushing or by blowing compressed air.

10. Air used for blowing shall be moist free. Inspection Report - Blasting F – 20 – 02 FM/PRM/PF Prepared By QA/ QC Manager Date: Approved By Executive Director Date:

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ADHESIVE COATING

Purpose: Scope: Reference: Responsibility: Procedure: Reference: Distribution:

To ensure that the application of adhesive is appropriate for Lining.

This procedures covers the timing and application guidelines for the different coats of the adhesive used.

Manufacturer specification and Material Safety Data Sheets. Production Manager (PRM) / Production Foreman (PF)/ Liner

1. The bonding agent as in the JOC is taken from the Store. 2. Mix thoroughly the contents in the tin before using.

3. Avoid exposure to sunlight and keep away from sources of ignition. 4. Before coating metal surface to be cleaned with Solvent.

5. Apply primer with out any dilution by brush/ spray / roller to get thin, uniform coating.

6. The primer coat should be allowed to dry for 30 – 40 minutes before the final coat.

7. Care should to be taken that all surface / including corners and bolt holes are fully covered.

8. Apply the final coat with out any dilution, taking care not to over brush.

9.

Coated surface should not be exposed to direct sun light. Inspection Report – Adhesive Coating F – 20 - 03

Material Data sheet. FM/ PRM / PF Prepared By QA/ QC Manager Date: Approved By Executive Director Date:

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Rubber Products Division Revision : 0 Page : 1

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RUBBER LINING

LINING

Purpose: Scope: Responsibility: Definitions: Procedure: Related Documents: Distribution:

To establish a procedure for the application of the rubber lining to tanks, pipes and other steel fabrications.

The procedure will define the steps involved in the application of the sheet in rubber lining. PF/ Liner.

Nil.

1.0 According to the JOC check whether the rubber sheet material is as per the requirement (compound code, thickness).

2.0 The Ok sheet is put on the table and care should be taken to avoid any grinding/dusting operations near it.

3.0 The un-vulcanized sheet is kept for shrinking.

4.0

Individual sheets shall be tailored to fit the surface to be lined. The edges are prepared as per the joint to be used

5.0 The contacting surface of the lining sheet shall be made tacky by either wiping with a solvent or the application of a coat of adhesive, the other surface is on the cloth or plastic film.

6.0 The sheets are allowed to dry for 10-15 minutes for the solvent to evaporate.

7.0 The tailored sheet is then taken carefully and positioned on the cemented metal and rolled with a stitcher and the cloth or the plastic film is removed gently. After the sheet is partially tacked in the place it should be rolled with a steady, firm over lapping stroke. The rolling or stitching should start at the center of the sheet and worked towards the edges.

8.0 It is essential that the rubber lining be rolled tightly against the metal surface to remove any trapped air and assure a complete contact between rubber and the metal. 9.0 Puncture any air blisters that are found with the help of a needle.

10.0 Stretching or applying tension to rubber sheets is to be avoided. Special care is to be given to avoid stretching in corners of right angled junctions. Use a proper shape piece as a stock that can be filled in sharp inside corners where stretching is a concern.

11.0 Rubber panels shall be joined together by making skived lip of approximately 1 to 2 inches.

12.0

The edge of the underlying panel is up skived at a slope of 45 ˚ and the over lapping panel is down skived at the same slope.

13.0 Where ever possible it is to be seen that the over lap joint made is in the direction of the product flow.

14.0

For lining nozzles and pipes a tube of the rubber is made and inserted through the pipe or nozzle and is stitched to remove trapped air.

15.0 At the end of the application of the rubber sheets a spark test is carried out at all places to ensure that the un vulcanized lining has no blisters or loose bonding. 16.0 In case any spark is observed then the area is repaired by filling and again spark

tested.

17.0 All uneven edges and excess rubber shall be trimmed properly. Inspection Report Lining F – 20 - 04

FM/ QAM/ PRM/LIC/ QCO/ PF.

Prepared By QA/ QC Manager Date: Approved By Executive Director Date:

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Page : 1

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CURING

To ensure the correct curing methods to achieve consistent quality Lining. All Rubber Lining products.

FM / QAM / PRM / PF/ Liner. Nil.

1. Curing characteristics are decided based on the compounds, type of cure and are written on the JOC.

2. Refer the JOC for curing conditions. Curing Sheet - Lining F - 20 - 05 FM/ QAM/ PRM/LIC/ QCO/ PF.

Prepared By QA/ QC Manager Date: Approved By Executive Director Date:

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OPERATION MANUAL

Issue : 1 Revision : 0 Page : 1

/ 1

RUBBER LINING

REPAIR OF RUBBER LININGS

Purpose: Scope:

Responsibility: Procedure:

To ensure that defects observed are rectified in pre and post Vulcanization of rubber Linings.

For all defects before and after Vulcanization.

Quality Assurance Manager (QAM) / Lab in charge (LIC) / Production Foreman (PF) / Operator

1.0 Repair Before Cure:

1.1 Remove the rubber by knife carefully in the defective area. 1.2 Grind defective area if required.

1.3 Clean the surface with Solvent. (Toluene or MEK)

1.4 Apply adhesive and rubber solution on the area to be repaired and allow it to dry. 1.5 After drying, the to-be-repaired area is lined using the same quality of un-vulcanized rubber.

2.0 Repair After Cure:

Repairs will be done after curing by any one of the methods 2.1. Hot Repair

2.2. Cold Repair

2.3. Self Curing Compounds 2.1 Hot Repair

2.1.1 The repair areas vary from small blister or cracks to major failure in numerous rubber sheets. The methods of repair are dictated by,

• The Type of Lining • Defects

• Extent of repair

2.1.2 Pinhole repair must be prepared by buffing and grinding. The surface of the rubber adjacent to the repair area to be buffed back for a minimum 2 – 3 inches around the periphery to ensure good bond between the parent and repair material.

2.1.3 Clean the buffing and grinding dust with brush or blow air. 2.1.4 Clean the buffed surface with solvent. (Toluene or MEK) 2.1.5 Apply the bonding agent and rubber solution.

2.1.6 After drying, the to-be-repaired area is lined with un vulcanized rubber sheet.

2.1.7 The repaired area is then vulcanized.

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Reference: Distribution:

vulcanized sheet to the size of repair area. 3.4. Clean the surface using solvent. (Toluene or MEK)

3.5. Apply one coat of metal primer on the metal surface and allow it for drying.

3.6. Mix 40 grams (4%) of hardener (UTR 20) with 1 Kg. of cold bonding agent (SC 2000) and stir well until a homogeneous mixture is obtained.

3.7. Apply two even and thin coats of hardener mixed bonding agent on the metal surface and vulcanized rubber sheet.

3.8. Allow the first coat to dry completely (at least 30 min.). Let the second coat dry until it is slightly tacky. (Check with the back of finger). In case of over drying, apply another coat.

3.9. Put the bonding surfaces on one another, avoiding air entrapment. Stitch vigorously or press firmly.

3.10. The stabilization period for the repair is minimum 12 hours. 2.3 Repair with self curing compound:

2.3.1 Remove the lined rubber completely until the metal surface is visible.

2.3.2 Grind / Buff the metal surface of the rubber Lined product. 2.3.3 Clean the ground surface using Toluene or MEK.

2.3.4 Apply one coat of repair solution over the ground area.

2.3.5 Fill the self curing compound by using the hand extruder or manually. 2.3.6 Two stage compounds should be mixed thoroughly in equal quantities

before applying.

2.3.7 Allow the repaired area for self-curing for 48 Hrs.

2.3.8 After curing is over, the area to be grinded smoothly and level the repaired area.

Rema Tip Top Manual. FM/SM/PRM/QAM/PF/ Liner Prepared By QA/ QC Manager Date: Approved By Executive Director Date:

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OPERATION MANUAL

Issue : 1 Revision : 0 Page : 1

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RUBBER LINING

FINAL INSPECTION AND TESTING

To ensure thorough inspection of Rubber Lining to avoid even a minor defect in the lining. The inspection practices of visual examination, spark testing for both before and after vulcanization and hardness check.

QAM / QCO/ LIC / PRM / PF Nil.

1.0

Visual Inspection :

On completion of the rubber lining operation, it is visually inspected with special attention to:

1.1 The linings shall be checked against the JOC to see that all areas conform to the requirements. The general appearance of the rubber surface is to be observed. The lining should be checked for wrinkles, blisters, depressions and de-laminations.

1.2 All joints shall be checked for looseness and uniformity.

1.3 Trapped air is detected by holding a light near the surface of the rubber and looking for shadow areas caused by the trapped air forming high spots. All trapped air should be removed before cure and repair to be made.

2.0 Spark Testing:

2.1 Before and after the rubber lining is cured, it must be tested with a spark tester to determine the presence of pin hole leaks, punctures, cuts etc. and are to be repaired.

2.2 All surfaces must be free of moisture, dirt, grit or foreign matter at the time of testing.

2.3 No curing is done until the complete lining is inspected and repairs made are re-inspected and found O.K.

3.0 Hardness:

3.1 Hardness of the rubber after cure is an indication of proper cure.

3.2 The readings are measured by the Durometer after the item is cooled to the ambient temperature.

3.3 In case the hardness values are less than the required the item is re-cured to achieve the maximum hardness.

3.4 The readings of the Durometer are taken by making a firm contact between the Durometer and the rubber surface making sure to record the initial highest reading.

3.5 Record approximately five readings per 100 square ft. to ensure representative readings.

Final Inspection Report – Lining F-20-06 FM/ QAM/QCO/ LIC / PF Reviewed By QA/ QC Manager Date: Approved By Executive Director Date:

(30)

Page : 1

/ 1

Purpose: Scope: Responsibility: Procedure: Reference: Distribution:

To ensure proper handling, shipment and storage of rubber lined items to avoid damage. To protect all the Lined items against damage.

Production Manger (PRM) /Quality Assurance Manger (QAM) / Stores In charge (SI) / Production Foreman (PF)

1. All vessels / items are to be lifted by Lifting equipment like Fork Lift, over head crane etc to prevent damage to the exterior of the items.

2. Lined equipment shall not be stored directly under sunlight. Tarpaulin/ thick fabric can be used to cover the rubber lined products.

3. Lined product should not be stored near sources of Ozone generation such as Welding machines and electric generators.

4. All branches, manholes, Pipe ends and other shall be protected from mechanical damage by using wooden blanks, plastics, plain rubber Sheets or other suitable materials.

5. Care should be taken to avoid lifting of vessels/ items so that chains and other lifting aids do not come in to contact with lined surfaces.

6. High local loads on the lined surfaces shall be avoided. 7. Product delivery is conducted as per delivery procedure.

8. Loose fittings shall not be placed inside Lined equipment while it is being transported.

9. Ladders, scaffolding poles are avoided inside the Lined equipment. Handling and Preservation of Materials QSP 27

Storage, Dispatch and Delivery QSP 28 FM/ SM / QAM / PRM / PF / SI Prepared By QA/ QC Manager Date: Approved By Executive Director Date:

(31)

.4.2

QUALITY PLAN – RUBBER LINING

PL-20-01

SL

No. Activity Responsibility EquipmentMachine / DocumentRef. Frequency RecordsQuality Location

1 compoundsReceiving

& Raw materials Stores in Charge

Fork Lift Hand operated

Trolley QSP 26 - - Stores

2 Initial Verification Stores in Charge Visual Delivery

Documents Every Delivery

F-26-01 F-26-02 F-26-05

Stores

3 Initial Inspection _{and Testing} Lab in Charge Lab Equipments Quality Plan Every Delivery F-33-01_F-33-02 Lab

4 _{Identification}Storage & Stores in Charge Visual QSP 24 Every Item - Stores

5 _productionIssue to _{Product. Foreman}Stores in Charge/ Hand operated Fork Lift Trolley

QSP 26, F-26-05

F-08-03, F-12-02 Every Item F-12-01 ProductionStores /

6 Mixing of Rubber _Compounds Mixing mill Operator

16” x12 “ mixing Mill Avery Balance Electronic Balance

CFC , WI – 20 - 01 100 % RG–13-01 Mill area

7 Testing of Rubber _Compounds Lab in charge Lab Equipments 100 % L–34- 01 LAB

8 Receiving of Lining

Components Stores in charge

Fork Lift Hand operated

Truck

Delivery

Documents 100 % - Factory or Site

9 Inspection of Preliminary Components

SI/ PF Visual PIR 100 % F–20- 01 Factory or _Site

10

Surface preparation and

Inspection Operator Blasting machine WI – 20 –01, lRB Random F–20- 02

Production Area

11 Adhesive coating Operator Brush / Roller WI-20-02, IRA - F–20- 03 Production _Area

12 Rubber Lining Operator Tools WI-20-03, IRL 100 % F–20- 04 Production _Area

13 Curing Moulding operator/ _{Prod. Foreman} Auto clave WI-20-04, IRC Every Item F -20-05 Production _Area

14 Final Inspection QAM, QAO, LIC, QCI Spark tester , Tape, Hardness meter , Venier,

QSP 35, IRF 100 % L -20-06 Inspection

Area

16 Delivery SCPO, PRM Fork Lift, Manual F – 08 - 03 All Lined item F– 08 – 06F–08 – 05

DN, Customer

MATERIAL TEST REPORT

Customer: Date:

(32)

Reference Standard:

F-20-01

PRE INSPECTION REPORT (PIR)

DATE:

NO. :

CUSTOMER NAME :

DESCRIPTION OF ITEMS:

SL

No Physical properties MethodTest Condition Units Specification Observed Value Remarks

1 Specific Gravity

-2 Hardness

3 Tensile Strength Kg/ Cm2

4 Elongation at Break %

5

After ageing properties at Change in Hardness Change in T.S. Change in E.B. 6 Compression Set at % 7 Oil resistance at Change in Volume %

Rubber Lining Procedure

RUBBER LINING FOR ABRASION AND CORROSION SERVICE

PROJECT

CLIENT

No.

Description

Doc. Nr.

Rev. Nr

1.

Contents

RL-01/01

0

2.

Introduction

RL-01/02

0

3

Reference Standards

RL-01/03

0

4

Design of Pipes and Structures

RL-01/04

0

5

Lining Materials

RL-01/05

0

6

•

•

Technical Data sheet for rubber material

Technical Data sheet for Priming and Bonding

solution

RL-08/01 to 04

0

7

Rubber Lining – Flow Chart

RL-09/04.01

0

8

Rubber lining Process Control

RL-01/06

0

9

Operation Manual – Pre Inspection of Lining

Components

RL 9.5

0

10

Operation Manual – Lining Material Selection

RL 9.6

0

11

Operation Manual – Surface Preparation

RL 9.10

0

12

Operation Manual – Adhesive Coating

RL 9.11

0

13

Operation Manual – Lining

RL 9.12

0

14

Operation Manual – Curing

RL 9.13

0

15

Operation Manual – Repair of Rubber Linings

RL 9.14

0

16

Operation Manual – Final Inspection and Testing

RL 9.15

0

17

Operation Manual - Handling, Storage, Packaging

and Delivery of rubber lined products

_•

_Components