SPECIFICATION FOR 10” PROTOTYPE CLEANING PROCEDURE

SPECIFICATION TABLE OF CONTENTS

1.0Purpose

2.0General

3.0Responsibilities

4.0Test Coupons

5.0Procedure

6.0Required Documentation

Attachment ACleaning and Testing Sequence Chart

1.0PURPOSE

This specification covers the minimum requirements for the cleaning of the 10” (bench scale) prototype vessel and its parts for the LIGO vacuum system.

2.0GENERAL

2.1Cleaning shall be performed by an engineer, technician or shop worker familiar with this procedure and the cleaning area systems and equipment. The manual for use of the pressure washer should be read and understood.

2.2Cleaning shall be done in the washing room of the Flanders Road building. The room contains the washing station consisting of a washing table with transparent curtained booth and drain collection and pumping. All drainage is collected in 55 gallon plastic drums located outside of the washing room.

2.3The cleaning equipment consists of the following:

Washing Station

Table with curtained wash booth.

Drain collection system

Exhaust vent system and room makeup air filter with 6” duct to cleaning booth

Water Supply

Water heater

Filters, meter and thermometer

Deionized (DI) water system

Pressure washer with nozzles and wands

Drying Gas Supply

Compressed nitrogen gas cylinder (hydrocarbon-free) with regulator

Gun and filter

2.4Stainless steel coupons (3” x 3”) will also undergo the same procedures as the 10” prototype vessel. A total of 24 coupons are provided. After each stage, as noted in the procedure (see Section 4, below), 2 coupons will be pulled out, wrapped and bagged, labeled and held for laboratory analysis of the surface. (See Section 4.0.)

3.0RESPONSIBILITIES

3.1Cleaning shall be performed by an engineer, technician or shop worker familiar with this procedure and the cleaning area systems and equipment.

3.2This procedure shall be maintained and modified as required by the cognizant engineer.

4.0TEST COUPONS

4.1Coupons shall be handled only with clean room gloves (powder-free latex or polyethylene).

4.2For each coupon, select one surface to be the front face, and one the back. On the back of each coupon, engrave or vibra-etch the coupon number (from 101 to 124).

4.3For weld wire samples, cutting tools used shall be clean and free of oil.

4.4Each test coupon shall be wrapped in oil-free aluminum foil and double bagged in clean polyethylene bags. Each outer bag shall be labeled with the following information:

PSI/LIGO Project

For XPS Analysis

P.O. No. ______

Sample No, ______

4.5Samples shall be sent via Federal Express to:

Evans East

Suite 1236

666 Plainsboro Road

Plainsboro, NJ 08536

ATTN: Mr. David Cole

5.0PROCEDURE

5.1Starting Condition

a..All welding completed.

b.Remove gross contamination from all interior surfaces (including flange face) with clean, lint free rag.

c.Coupons prepared as above. Remove coupons No. 101 and No. 102 and prepare as in Section 4.0, above.

5.2Equipment Set-Up

a.Confirm proper piping connection, wiring connection and valve lineup for the pressure washer (including the water heater), DI water system and drying gas system.

b.Confirm proper connections (piping and wiring) for the cleaning station, including the sump pump system and vent fan.

c.Confirm that the sump pump is piped to a plastic drum having at least 20 gallons of capacity.

d.Charge the detergent tank on the pressure washer with approximately 1 quart of liquid detergent concentrate.

e.Confirm that the pressure washer is piped to the double wand and is ready at the cleaning station. Be sure that the wand has a 25 degree low pressure nozzle and a 25 degree high pressure nozzle installed and that they are tight.

f.Confirm that the DI water rinse spray wand is ready at the cleaning station.

g.Confirm that the drying gas wand is ready at the cleaning station.

5.3Steam Cleaning

a.The 10” prototype vessel will not be steam cleaned, but the material used for the shells of the full scale chambers and components will be. For this reason, steam clean (without detergent) the remaining test coupons. Allow them to gravity drain and air dry.

b.Remove coupons No. 103 and No. 104 and prepare as in Section 4.0, above.

5.4CO2 Cleaning

a.CO2 clean coupons 105-112.

b.Remove coupons No. 105 and No. 106 and prepare as in Section 4.0, above.

5.5Cleaning Precautions

5.5.1There shall be a minimum of two operators present for all cleaning operations.

5.5.2The operator doing the washing shall wear a lab coat, shoe covers and clean room gloves. (This applies to anyone handling the cleaned pieces.)

5.5.3The operators should be familiar with the pressure washer instruction manual before operating the equipment.

5.5.4Do not let any surface dry between start of washing and end of final rinse.

5.5.5Handle each piece or component with appropriate care and clean gloves.

5.6Cleaning

5.6.1General

a.When using a spray, spray over all surfaces slowly, starting with flange faces and including flange annulus openings.

b.Spray with the nozzle approximately 3” from the surface being cleaned, and moving approximately 2” per second. Overlap passes slightly. When cleaning outside surfaces (non-vacuum surfaces) a rate of 4”-6” per second can be used.

c.For hot water, the heater should be set to provide approximately 120 F water.

d.Periodically during cleaning, monitor and make note of the water flow rate and temperature. When using DI water, also monitor the quality light at the DI system. All of these instruments are located outside of the washing room.

e.Wash coupons numbered 107-118 in accordance with this procedure.

5.6.2Wash

a.Confirm that all valves are lined up to feed hot water to the pressure washer.

b.Start the cleaning booth ventilation fan.

c.Start the pressure washer.

d.Using the low pressure nozzle in the double wand, spray all surfaces of the piece to be cleaned. Include the outside surfaces.

e.After completely washing all surfaces, immediately go on to the 1st hot rinse.

5.6.31st Hot Rinse

a.Twist the handle on the double wand to switch to the high pressure hot rinse.

b.Spray all surfaces (inside and out) to remove all traces of detergent.

c.On completion, turn off the pressure washer and close its inlet water valve.

5.6.4DI Water Rinse

a.Open the water supply valves to the DI water system and the spray wand.

b.Using the DI water hose and spray wand, spray the piece to remove all previously used rinse water.

c.On completion, close the DI water supply valve.

5.6.5Drying

a.Drying will be accomplished by blowing clean nitrogen gas over the piece. Using the blow gun, blow off any surface water remaining on the piece. Be sure to also go over all surfaces, internal and external to ensure dryness.

b.Inspect and bag the piece immediately after drying.

c.Remove coupons 107, 108, 113 and 114 and prepare as in Section 4.0, above.

d.Bag the remaining coupons as in 5.8, below.

5.7Inspection

a.Inspection shall be done (before removing the piece from the washing room) using a black light on all interior surfaces.

b.The presence of any hydrocarbon or fingerprints on any interior surface or flange face shall be cause for rejection. This will require CO2 cleaning to rectify.

c.A visual inspection shall be made of exterior surfaces. Any hydrocarbon or fingerprints shall be wiped with a clean room wipe or cleaned with CO2. If wiping is performed, it shall be followed by CO2 cleaning.

5.8Bagging/Wrapping

a.Immediately after drying, double bag the piece using clean, oil-free polyethylene bags or wrap and seal using the aluminum foil provided.

b.Only cleaned, bagged or wrapped parts may be brought into or out of the clean room, unless going for recleaning.

6.0Required Documentation

The following documentation shall be provided on completion of cleaning:

  • Cleaning log describing parts cleaned and procedure used
  • Record of flow rates and temperatures used
  • Record of inspection results

V049-2-085