Series 20 Weld Head User’s Manual Weld Head The Series 20 SWS weld head delivers consistent, precise welds for outside tubing diameters from 1/2 to 2 in. and 12 to 52 mm and pipe diameters ranging from 1/4 to 1 1/4 in. and 10.2 to 48.3 mm. A DC motor in the weld head drives a rotor, which carries the tungsten electrode around the weld joint.
• weld head • arc gap gage • electrode package • tool package Perform the following steps when your Swagelok Series 20 Weld Head arrives: 1. Inspect the container for damage. 2. Remove the components from the container. 3. Check the items for any damage.
This connection is the positive (+) terminal of the weld head. 5. Insert the weld head shielding gas connector into the Swagelok Quick-Connect stem labeled TO WELD HEAD. Ensure that the connector is firmly attached. This connection provides shielding gas to the weld head through a mass flow controller (MFC) in the power supply.
Series 20 Weld Head User’s Manual Installing the Electrode in the Weld Head This Swagelok weld head comes with a selection of electrodes. The following instructions show how to properly install an electrode in the weld head. Selecting the Proper Electrode Electrode length and diameter depend on your weld head model and the outside diameter of the work piece being welded.
Series 20 Weld Head User’s Manual Electrode Geometry This illustration shows the electrode shape Swagelok suggests. Properly ground electrodes provide consistent, repeatable welds. Pre-ground electrodes are available from your Swagelok representative. See your parts list for ordering information. The electrode part numbers are assigned as follows: CWS –...
Series 20 Weld Head User’s Manual Calculating Arc Gap Gage Settings To determine the arc gap gage setting for a specific arc gap, use the formula below. Arc Gap Gauge Setting Where A = largest OD on the weld end of the tubing or fitting (welding diameter). B = Arc gap gage diameter C = desired arc gap Figure 7...
Series 20 Weld Head User’s Manual Setting the Arc Gap The proper arc gap setting facilitates control of the weld and improves consistency. The following steps cover how to set the arc gap. The arc gap is set by using the arc gap gage provided with the weld head.
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Series 20 Weld Head User’s Manual Table 2 SWS-20H Arc Gap Gage Dia. 3.118 in. Setting Setting Setting Setting Setting Setting Setting Setting Setting Setting Nominal Actual 0 .030 in . 0 .040 in . 0 .050 in . 0 .060 in . 0 .070 in . 0,5 mm 0,64 mm 0,76 mm...
Series 20 Weld Head User’s Manual Inserting the Electrode into a Rotor 1. Without the fixture block attached, press ELECTRODE CHANGE on the operator panel. The electrode will move to the position shown in Figure 9. 2. Loosen the two electrode clamping screws. If you are replacing the electrode, remove the electrode.
Series 20 Weld Head User’s Manual Setting the Arc Gap 1. Use JOG or ELECTRODE CHANGE to position the rotor as shown. This allows access to the electrode clamping screws. 2. Insert the arc gap gage into the rotor. See Figure 10(A). 3.
Series 20 Weld Head User’s Manual Preparing the Work It is important to prepare the tube pieces properly before welding. Refer to Figure 11. Tubing must be square and burr-free to ensure repeatable, high- quality autogenous fusion welds. Cut the tubing to length with a hacksaw or tube cutter.
Series 20 Weld Head User’s Manual Fixturing the Work Select or configure the appropriate fixture block. Select the collets to match the work outside diameter. Selecting the Fixture Block and Collets 1. Select the fixture block that accepts the outside diameter of the tube to be welded.
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Series 20 Weld Head User’s Manual Installing the Collets in a Tube Fixture Block 1. Release both levers and open the tube fixture block. See Figure Figure 12 Opening the Fixture Block 13-205R4.indb 15 2/1/13 2:43 PM...
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Series 20 Weld Head User’s Manual 2. Install the collet halves in both the top and bottom side plates and tighten the collet screws. Make sure the collet shoulder is flush against the fixture side plate. See Figure 13. Fixture Side Plate Collet Shoulder Figure 13...
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3. Lock down the top side plate. See Figure 15(B). 4. Remove the centering gage. Figure 14 Place the Centering Gage Note: When welding a Swagelok ATW fitting to tubing, butt the tubing against the centering gage first. Figure 15 Placing First Work Piece in the Fixture Block 13-205R4.indb 17...
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Series 20 Weld Head User’s Manual 5. Butt the second work piece against the first work piece, and lock down the top side plate. See Figure 16. 6. Inspect 360° around the weld joint for fit and alignment. If the alignment is not correct proceed to the next section.
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Series 20 Weld Head User’s Manual Adjusting the Fixture Block The modular design of the Series 20 Fixture Block allows you to assemble the block to meet a variety of welding requirements. To align tubing in the fixture block follow these steps: 1.
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Series 20 Weld Head User’s Manual Mating the Weld Head to the Fixture Block 1. Rotate the locking lever on the weld head counter-clockwise until it stops. See Figure 21. 2. Insert the weld head into the fixture block. See Figure 22(A). 3.
Series 20 Weld Head User’s Manual Maintenance To ensure your Swagelok Welding System (SWS) equipment is always Note: in proper working order, you must perform periodic maintenance on the system components. If you experience problems while performing the procedures in this section, refer to the...
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Series 20 Weld Head User’s Manual Fixture Block Daily Maintenance Non-Anodized Surfaces At the start of each work day: Under the Collets 1. Inspect the fixture block for cleanliness, wear and damage. See Figure 23. 2. Remove dirt, carbon, and vapor deposits from the fixture block with a clean, soft cloth.
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Repeat for the other side of the fixture block. If any wear or damage is found or the fixture Contact your authorized Swagelok representative to return the fixture block is not properly securing the work piece, block for service.
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Series 20 Weld Head User’s Manual Weld Head Daily Maintenance Perform weld head maintenance daily and every 500 to 700 welds. Depending on usage and wear, maintenance may be performed before WARNING! the 500-weld mark. Disconnect the WORK and ELECTRODE cables from the power supply before performing the adjustment or At the start of each work day:...
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Series 20 Weld Head User’s Manual Weld Head Disassembly and Cleaning This section describes how to disassemble the weld head and rotor. Weld Head Screws Locking Ring To disassemble the weld head, follow these steps: Plate Locking Ring 1. Blow any loose material from the weld head assembly with clean, low-pressure air.
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Series 20 Weld Head User’s Manual 5. Remove the weld head housing screws from the housing. Using a slight rocking motion, carefully separate the work side of the weld Housing head housing from the motor side. See Figure 28. Screws 6.
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Series 20 Weld Head User’s Manual 9. Examine the brush. See Figure 31. Brush Inspect and clean the brush using the following steps: a. Check the brush for excessive wear. b. Verify that the brush has a groove. Replace the brush if the groove is not present.
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Series 20 Weld Head User’s Manual Rotor To disassemble the rotor, follow these steps: Rotor Screw Electrode 1. Remove the rotor screws and the electrode clamping plate screws Clamping from the rotor. Remove the electrode from the ceramic insert. See Plate Screw Figure 34.
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Series 20 Weld Head User’s Manual 7. Remove the ceramic insert. See Figure 37. Ceramic Insert 8. Inspect the ceramic insert. If it has carbon or other deposits, clean it with a fine-grit abrasive pad or soft nylon brush. 9. Remove the electrode clamping plate. Clean it with a fine-grit abrasive pad.
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Series 20 Weld Head User’s Manual 13-205R4.indb 30 2/1/13 2:43 PM...
This section includes exploded assembly drawings and associated parts lists. These drawings are provided as a guide to identifying part names. For specific part ordering information, contact your authorized Swagelok representative. The parts identified in this section include: • SWS-20H Weld Head • SWS-20H Motor and Power Block Assembly...
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Series 20 Weld Head User’s Manual Figure 40 SWS-20H Weld Head 13-205R4.indb 32 2/1/13 2:43 PM...
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Plastic Socket Head Cap Screw, 13105 6-32 x 0.437 in. SS Dowel Pin Split Lock Washer 13208 For part ordering information, contact your authorized Swagelok representative. * Not available as a field replacement spare part. 13-205R4.indb 33 2/1/13 2:43 PM...
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Series 20 Weld Head User’s Manual Figure 41 SWS-20H Motor and Power Block Assembly 13-205R4.indb 34 2/1/13 2:43 PM...
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SS Socket Head Cap Screw, 2-56 x 0.187 in. 13111 Wire Ring Terminal SS Slotted Head Screw, 4-40 x 0.250 in. 188-21066-RCEU For part ordering information, contact your authorized Swagelok representative. * Not available as a field replacement spare part. 13-205R4.indb 35 2/1/13 2:43 PM...
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Series 20 Weld Head User’s Manual Figure 42 SWS-20H Rotor Assembly 13-205R4.indb 36 2/1/13 2:43 PM...
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SS Socket Head Cap Screw, 2-56 x 0.250 in. 13176 Electrode Clamping Plate 11306 Ceramic Insert 11210 See Electrode Chart (page 4) For part ordering information, contact your authorized Swagelok representative. * Not available as a field replacement spare part. 13-205R4.indb 37 2/1/13 2:43 PM...
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SS #4 External Star Washer 13171 Centering Gage SWS-20CG-A 12 in. Lanyard 13231 SS #10 External Star Washer 13131 For part ordering information, contact your authorized Swagelok representative. * Not available as a field replacement spare part. 13-205R4.indb 39 2/1/13 2:43 PM...
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Series 20 Weld Head User’s Manual Figure 44 SWS-20FSP1R Special Purpose Side Plate 13-205R4.indb 40 2/1/13 2:43 PM...
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SS Set Screw, 4-40 x 0.125 in. 12132 Latch Holder (right bottom) 12314 Threaded Insert Dowel Pin For part ordering information, contact your authorized Swagelok representative. * Not available as a field replacement spare part. 13-205R4.indb 41 2/1/13 2:43 PM...
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Series 20 Weld Head User’s Manual Figure 45 SWS-20FSP1L Special Purpose Side Plate 13-205R4.indb 42 2/1/13 2:43 PM...
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SS Flat Head Screw, 6-32 x 0.313 in. 13318 Dowel Pin Locking Tab 12360 Lever Cam Assembly 12130-2 Threaded Insert For part ordering information, contact your authorized Swagelok representative. * Not available as a field replacement spare part. 13-205R4.indb 43 2/1/13 2:43 PM...
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Series 20 Weld Head User’s Manual Warranty Information Swagelok products are backed by The Swagelok Limited Lifetime Warranty. For a copy, visit swagelok.com or contact your authorized Swagelok representative. 13-205R4.indb 44 2/1/13 2:43 PM...
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