Instructions - Parts MD2 Valve 312185S EN For use with disposable mixers to dispense a variety of sealants and adhesives. For professional use only. 120 psi (0.84 MPa, 8.4 bar) Maximum Air Inlet Pressure Important Safety Instructions Read all warnings and instructions in this manual. Save these instructions. See page 2 for model information, including maximum working pressure and approvals.
MD2 Valve Models Contents MD2 Valve Models . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Component Identification . . . . . . . . . . . . . . . . . . . . 5 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Operation . . . . . . . . . .
Warnings Warnings The following warnings are for the setup, use, grounding, maintenance, and repair of this equipment. The exclamation point symbol alerts you to a general warning and the hazard symbol refers to procedure-specific risk. Refer back to these warnings. Additional, product-specific warnings may be found throughout the body of this manual where applicable. WARNING SKIN INJECTION HAZARD High-pressure fluid from dispense valve, hose leaks, or ruptured components will pierce skin.
Warnings WARNING FIRE AND EXPLOSION HAZARD Flammable fumes, such as solvent and paint fumes, in work area can ignite or explode. To help prevent fire and explosion: • Use equipment only in well ventilated area. • Eliminate all ignition sources; such as pilot lights, cigarettes, portable electric lamps, and plastic drop cloths (potential static arc). • Keep work area free of debris, including solvent, rags and gasoline.
Component Identification Component Identification C B F A D H C G B E TI10391A FIG. 1: Component Identification Key: A B C D E F G H Snuff-back adjustment knob (soft seat versions only) 1/8 in. npt (f) air to close (O). 1/8 in. npt (f) air to open (I).
Features Features Electric Switch Valve Pneumatic Valve 1/4 in npt (f) air inlet Series A handle shown TI10383A TI10407A Normally open momentary contact switch Note: The Trigger/Lever activates an electrical switch in the handle, which activates a remote 4 way solenoid valve. Bring an “OPEN” air signal to the 1/8 in. npt(f) port (I) on this side of the valve, and a “CLOSE” signal to the port (O). See Accessories, page 23, to order fittings and tubing. The 1/8 in.
Installation Installation Grounding The following grounding instructions are minimum requirements for a basic dispensing system. Your system may include other equipment or objects which must be grounded. Check your local electrical code for detailed grounding instructions for your area and type of equipment. Your system must be connected to a true-earth ground. • • • • • • • • Pump: ground the pump by connecting ground wire and clamp as described in your separate pump instruction manual.
Setup Setup Fluid and Air Connections Selecting Hoses 9/16 Straight Thread O-Ring Boss Fluid Inlets Hoses between your proportioner and the MD2 valve should be selected carefully. Many factors effect hose selection. There is one fluid inlet on the A-side and one fluid inlet on the B-side. The fluid inlets are located on the side of the valve and swivel to permit various mounting and hose configurations.
Setup System Start-up When initially loading the fluids through the system, leave the mixer off until both fluids flow freely from the nose piece without any air. This prevents cross contamination from having fluid on one side pushing back up the other side. Mixer Selection Disposable mixers are available from 3/16 in. I.D. to 1/2 in. I.D. in lengths from 12 elements to 36 elements. In general, wide viscosity or mix ratios require more mix elements. Small I.D.
Operation Operation Pressure Relief Procedure • • 1. Shut off the air to the supply pumps. 2. Close the bleed-type master air valve (required in your system). 3. Hold a metal part of the valve firmly to the side of a grounded metal pail, and trigger the dispense valve to relieve pressure. 4. Shut off the air to the dispense valve, if applicable.
Maintenance Maintenance Daily Shutdown When you are through using the MD2 valve, the outlet to the mixer should be cleaned and protected from drying or crystallization. 1. Remove and properly dispose of the static mixer. 2. Dispense a shot of material into a waste container to clear any crossover in the nosepiece. 3. Wipe the nose with a clean rag being careful not to let the materials contact each other. 4. Install the PTFE night cap (1:1 valves - 15K652, 10:1 valves - 15K628) and retaining nut (15K688).
Troubleshooting Troubleshooting Problem Valve does not open. Valve does not close and leaks. Cause Solution Insufficient air pressure. Turn on air or increase air pressure. Air not exhausted from the front side of air cylinder piston. Use 4-way, relieving type air valve. Insufficient air pressure. Turn on air or increase air pressure. Air not exhausted from the back side Use 4-way, relieving type air valve. of air cylinder piston. Blockage between needle and seat.
Repair Repair Disassembly 5. Remove the two fluid housing screws (18) and clamps (17) from the fluid housing (14). Slide the fluid housing (14) off of the air cylinder (2). See FIG. 5. 6. Remove the bearings (11), bearing o-rings (36, 13), and secondary fluid seals (12, 15). 1. Relieve all air and fluid pressure, page 10. 2 2. Disconnect the valve from the system. 16 11 NOTE: In the following steps, keep the parts from the A side and B side separate to prevent cured material from forming on them. 3.
Repair 7. Remove the retaining ring (1) from the back of the air cylinder (2). Push the two shafts (5) into the air cylinder (2) to dislodge the air cylinder cap (22). See FIG. 6. 204 210 8. Push the two shafts (5) to dislodge the piston (9) assembly from the air cylinder (2). 213 203 202 9. Use an o-ring pick to remove the o-rings (23) and use a screwdriver to remove the sleeve bearings (7) from the air cylinder (2). 203 10. Remove the o-rings (6) from the piston (9) and air cylinder cap (22). 11.
Repair Reassembly 6. 255179 and 255181, Insert the seals (26) with the springs facing into the fluid housing (14). Air Cylinder Section 7. With the “X” on the nosepiece on the same side as the “MD2” on the air cylinder, install the nosepiece (31) with the o-rings (20), seats (27), and nosepiece screws (19). Tighten the nosepiece screws to 115-120 in-lb (14-15 N•m). 1. Lubricate the shaft o-rings (23) and the bearings (7). Insert o-rings into the air cylinder (2) and air cap (22) cavities.See FIG. 6.
Parts Parts 255179 and 255181 29 2 255181 18 16 1 17 47 30 12✖ 11 13✖ 36✖ 15✖ 2 19 29 14 20*† 26* 27* 1 4❖✖ 25* 5✖ 8 7❖ 39 2 23❖ 1 24 23❖ 21 1 22 1 Torque to 25-30 in-lb (2.8-3.4 N•m). 2 Torque to115-120 in-lb (14-15 N•m).
Parts MD2 Valve The parts listed below are common to all MD2 Dispense valves. Parts which vary are found in the table at the bottom of this page. Ref 1 2 3 4❖✖ 5✖ 6❖ 7❖ Part 120762 15K496 102920 157628 15K421 156593 551181 8 9 11 12✖ 13✖ 14 15✖ 16 17 18 551183 626067 15K422 551191 113746 15K441 120768 15K442 15K444 121224 Description RING, retainer HOUSING, air cylinder NUT, lock O-RING, buna-n SHAFT, primary O-RING, buna-n BEARING, sleeve 1/4, 3/8, 1/4, nylon PIN, dowel 1/8 x 1.
Parts 255180, 255182, and 255183 16 18 2 1 29 29 255182 47 30 17 12✖ 11 13✖ 36✖ 15✖ 2 19 14 26† 28† 20*† 27† 4❖✖ 25† 5✖ 8 7❖ 39 2 23❖ 1 6 22 1 Torque to 25-30 in-lb (2.8-3.4 N•m). 2 Torque to115-120 in-lb (14-15 N•m).
Parts MD2 Valve The parts listed below are common to all MD2 Dispense valves. Parts which vary are found in the table at the bottom of this page. Ref 1 2 3 4❖✖ 5✖ 6❖ 7❖ Part 120762 15K496 102920 157628 15K421 156593 551181 8 9 11 12✖ 13✖ 14 15✖ 16 17 18 551183 626067 15K422 551191 113746 15K441 120768 15K442 15K444 121224 Description RING, retainer HOUSING, air cylinder NUT, lock O-RING, buna-n SHAFT, primary O-RING, buna-n BEARING, sleeve 1/4, 3/8, 1/4, nylon PIN, dowel 1/8 x 1.
Parts Electric Switch Handle, 255208 NOTE: Extension cable 123660 is available. 112* 1 1 105 111* 2 115* 106 114* 116 113 120 119* 104 101 TI14761A TI10384B Series B handle shown 1 Torque to 25 in-lb (2.8 N•m). 2 Torque to 125-135 in-lb (14-15 N•m).
Parts Pneumatic Handle, 255206 204 216 4 210 215 213 203 211 3 3 2 202 203 2 214 207 1 Torque to 35 in-lb (4 N•m). 205 2 Apply lubricant on seals. 3 Apply thread sealant. Torque to 130 in-lb (15 N•m). 4 Torque to 25 in-lb (2.8 N•m).
Parts Actuated Lever, 255249 302 305 1 307 319 303 304 308 306 310 1 301 309 303 1 Torque to 25 in-lb (2.8 N•m). TI10410B Ref 301 302 303 304 305 306 307 308 309 310 311 319 22 Part 15K922 121191 100015 100016 192272 203953 551318 121192 121193 15M479 121194 Description BLOCK, mounting lever, 2K BOLT, eye, 1/4-20 x 2 in.
Accessories Accessories Plastic Tube Fittings to Connect Air Signals Tube OD 1/8 NPT (M) Straight 1/8 NPT (M) 90° Swivel 5/32 in. 1/4 in. 114263 115671 114151 112698 Tube OD 1/4 NPT (M) Straight 1/4 NPT (M) 90° Swivel 5/32 in. 1/4 in. 598252 104165 114469 114109 Inlet Check Valves (3000 psi working pressure) Part No. Size 501867 501684 949709 949710 1/4 NPT (M x M) 3/8 NPT (M x M) 3/8 NPT (M x M) 3/8 NPT (M x M) Description 303 sst with PTFE o-ring poppet (2 psi crack pressure).
Accessories Plastic Tubing for Air Signal Lines Part No. Description 514607 5/32 in. O.D. Nylon C12509 1/4 in. O.D. Nylon Mixers and Shroud ID x # elements 50 pack 250 pack Shroud 3/16 x 32 LC0077 LC0084 LC0063 1/4 x 24 LC0078 LC0085 LC0057 3/8 x 24 LC0079 LC0086 LC0058 3/8 x 36 LC0080 LC0087 LC0059 3/8 Combo LC0081 LC0088 LC0060 3/16 x 32 Luer Lock LC0082 LC0089 LC0061 1/4 x 24 Luer Lock LC0083 LC0090 LC0062 Nose Piece Accessories Part No.
Accessories Orifice Kits In the following table, shaded rows indicate “Super Standard” items that are typically stocked and provide the best delivery dates. Impingement Kit Type and Kit Number Impingement Kit Type and Kit Number Port Size Port Size 250 Model Polyol 250 Model Iso 250 Model Polyol 250 Model Iso in. mm Orifice Kit Orifice Kit in. mm Orifice Kit Orifice Kit 0.016 0.41 24C805 24D229 0.047 1.19 24C753 24D225 1.32 24C811 24D235 0.020 0.51 24C751 24D223 0.052 0.024 0.
Accessories 24E505 Orifice Block Kit Part 122737, Swivel Adapter - JIC 6 x 1/4 npt, not included in kit Part 122961, Swivel Adapter - JIC 5 x 1/4 npt, not included in kit 401 402b 402a 1 2 MD2 Valve not included 401d 401b 401c 401a ti21829a1 1 Lubricate all o-rings and specified surfaces. 2 Torque to 20-30 in-lb (2.2-3.4 N•m). Ref. 401 401a 401b 401c 401d 402 402a 402b Part 123886 117724 Description Qty.
Accessories Valve Accessories 551351 Short Throw Spacer 123660 Extension Cable, 6.0 m (19.7 ft) A spacer under the air piston that limits how far the fluid needles push open. It reduces the amount of material surge when the valve opens, and reduces the amount of snuff-back available. Used for dispensing low flow small diameter beads. For 255180 and 255182 only. For locating the valve further from the base system than allowed with the original cable provided.
Accessories Front Valve Repair Kits Angled Adapter Kits Part No. Description 255219 Repair Kit for adjustable snuff-back valves 255179 and 255181 only. 255220 Repair Kit for non-adjustable snuff-back valves 255180, 255182, and 255183 only. G 1/2 Outlet Kit Part No. Description 16T802 Adapter to allow for the mounting of G 1/2 threaded mixers. Applicable for 10:1 MD2 valves only. 24W045 - 25° angle 24W046 - 15° angle 24W047 - 5° angle Ref. Part Description Qty.
Technical Data Technical Data Maximum Fluid Pressure 255179-255182: 3000 psi (20.7 MPa, 207 bar) 255183: 2000 psi (13.8 MPa, 138 bar) 120 psi (0.84 MPa, 8.
Graco Standard Warranty Graco warrants all equipment referenced in this document which is manufactured by Graco and bearing its name to be free from defects in material and workmanship on the date of sale to the original purchaser for use. With the exception of any special, extended, or limited warranty published by Graco, Graco will, for a period of twelve months from the date of sale, repair or replace any part of the equipment determined by Graco to be defective.
