SOLVENT CEMENT WELDED CONNECTIONS
Spears® Manufacturing Company recommends following solvent cement manufacturer’s recommendations and reading ASTM D 2855, "Standard Practice for Making Solvent-Cemented Joints with Poly Vinyl Chloride (PVC) Pipe and Fittings". This method of joining valves and piping system components is very simple and reliable if procedures are followed correctly. Since variables of temperature, humidity, pipe size , time, and other conditions have a significant effect on solvent cement joints, it is important to understand the principles of each step and make adjustments for actual conditions. Shortcuts or excessive deviations may result in joint failures and/or frozen valve movements.
WARNING: NOT FOR DISTRIBUTION OF COMPRESSED AIR OR GAS
(see also, "Precautions & Warnings for All Installations").
SAFETY PRECAUTIONS
WARNING: Solvent cements and primers for pipe, fittings and valves are flammable. Extinguish all smoking material, flames, or other ignition sources in working or storage areas. Be sure to work only in a well-ventilated space. Avoid eye and unnecessary skin contact with all cements, primers or solvents. Ingestion or intentional inhalation of solvent vapors can be harmful or fatal. Additional safety precautions may apply. Consult solvent cement manufacturer.
SELECTION OF SOLVENT CEMENTS
A wide variety of solvent cements and primers are commercially available. Selection of specific type, grade and consistency of solvent cement should take into account pipe type, size, installation conditions and chemical compatibility of cement and system fluids. Contact solvent cement manufacturer for additional information.
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REQUIRED MATERIALS
- Saw & miter box or wheel-type cutter
- Pipe deburring & beveling tool or mill file
- Solvent Cement - PVC cement for PVC materials, CPVC cement for CPVC materials; heavy bodied, such as manufactured by IPS (Weld-On) Corporation
- Primer - such as manufactured by IPS (Weld-On) Corporation.
- Brush or dauber type cement and primer applicators - select a size no less than 1/2 the pipe diameter (see chart below).
- Use containers - sealable metal or glass to hold cements and primers
- Cotton cleaning rags
- Cleanup solvents - such as tetrahydrofuran (THF) or methylethylketone (MEK)
RECOMMENDED APPLICATOR SIZE FOR SOLVENT CEMENTS & PRIMERS
Nominal Pipe Size (in.) | 1/2, 3/4, 1 | 1-1/4, 1-1/2, 2 | 2-1/2, 3 | 4 | 6 |
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Brush* | 1/2 | 1 | 1-1/2 | 2 | 3 |
Dauber | 3/4 | 1-1/2 | NR | NR | NR |
Roller | NR | NR | NR | 3 | 3 |
* Always use a natural bristle brush.
NR = "Not Recommended"
PREPARATION
For best results, installation should be made at temperatures between 40°F and 110°F.
All joint components should be inspected for any breaking, chipping, gouging or other visible damage before proceeding. All pipe and fittings should be removed from their packaging or containers and exposed to the installation environment for a minimum of one hour in order to thermally balance all components.
On True Union Ball, Check, and Diaphragm valves, remove union nuts and end connectors before priming and cementing connections. With the threads facing the valve, slide the union nut over the pipe to which the end connector socket is to be cemented. Reinstall the valve body and union nuts only after the joint has fully cured.
On valves with fixed socket connections in the body, be sure the valve is in the open position to aid in evaporation of solvent vapors which can attack internal components. TAKE EXTRA CARE THAT NO PRIMER OR SOLVENT CEMENT IS ALLOWED TO COME IN CONTACT WITH THE BALL OR OTHER INTERNAL VALVE COMPONENTS.
GENERAL PROCEDURE
Step 1: Cut Pipe Square
Pipe ends must be cut square, using a wheel-type cutter or saw & miter box. A fine-toothed hand saw (16-18 teeth/inch) with little or no set is recommended. A power cutoff saw with carbide blade is recommended for high volume cutting.
Step 2: Deburr & Bevel Pipe
Regardless of cutting method used in step 1, burrs are created which must be removed from both the pipe I.D. and O.D before joining. All pipe ends should be beveled 10° to 15°. Commercially available deburring & beveling tool is recommended, or a mill file may be used.
Step 3: Clean Joint Components
Wipe away all loose dirt and moisture from the pipe O.D. and fitting I.D. with a clean, dry cotton rag. DO NOT ATTEMPT TO JOIN WET SURFACES.
Step 4: Check Joint Interference Fit
An interference between pipe and fitting socket is necessary for proper fusion of the joint. To check, lightly insert pipe into fitting socket. DO NOT FORCE. Interference between pipe and fitting should occur between 1/3 to 2/3 of the socket depth (full interference fit) and the socket bottom (net fit). Do not use components which improperly mate.
Step 5: Apply Primer
Primer is necessary to penetrate and soften both pipe and fitting socket surfaces in order for the solvent cement to properly bond. THE MOST FREQUENT CAUSE OF JOINT FAILURES IS INADEQUATE SOLVENT PENETRATION AND SOFTENING OF BONDING SURFACES DURING THE WELDING OPERATION.
1.) Using a brush or applicator size no less than 1/2 the pipe diameter, apply a liberal coat of primer with a scrubbing motion to the fitting socket until the surface is softened and semi-fluid. This may take 5 to 15 seconds depending on size and temperature (larger diameters and lower temperatures will increase required time).
2.) Apply primer to pipe in the same manner, extending application area to slightly more than the insertion depth into the fitting socket.
3.) Apply a second coat to both the fitting socket and the pipe.
4.) Check penetration and softening by scraping the primed surfaces. A few thousands of the semi-fluid surface should be easily removed. Repeat primer application if necessary.
Step 6: Apply Solvent Cement
Solvent cement must be applied IMMEDIATELY to primed surfaces before the primer dries in an alternating 3-coat application. Using a brush or applicator size no less than 1/2 of the pipe diameter, apply a liberal coat of solvent cement to the primed pipe surface, then apply a light to medium coat to the primed fitting socket. If a "net fit" was experienced in during dry fit check (Step 4), apply an additional coat again to the pipe surface. BE SURE TO USE A VERY LIBERAL AMOUNT OF SOLVENT CEMENT ON PIPE.
VALVE INSTALLATION CAUTION: TAKE EXTRA CARE THAT NO PRIMER OR SOLVENT CEMENT IS ALLOWED TO CONTACT THE BALL OR OTHER INTERNAL VALVE COMPONENTS.
Step 7: Join Components
IMMEDIATELY following application of cement and before it starts to set, insert the pipe into the fitting socket with a 1/4 turn, twisting motion to evenly distribute cement within the joint. A full bead of cement should form around the circumference of the joint. Hold joint together for approximately 30 seconds to make sure the pipe does not move or back out of the socket.
CAUTION: ABSENCE OF BEAD FORMATION, VOIDS, OR GAPS IN THE BEAD ARE A SIGN OF INSUFFICIENT CEMENT APPLICATION. IF SUCH IS OBSERVED, IMMEDIATELY PULL THE JOINT APART AND REAPPLY AN ADEQUATE AMOUNT OF CEMENT.
Step 8: Remove Excess Cement
Using a cloth, wipe clean all excess cement from the exterior juncture of the pipe and fitting.
Step 9: Initial Set Time
The joint must not be handled or moved for a minimum of 2 minutes, after which the joint must be handled carefully until the cement has gone through a set period.
Recommended Initial Set Time:
30 mins minimum at 60 to 100°F (15 to 40°C);
1 hour minimum at 40 to 60°F (5 to 15°C);
2 hours minimum at 20 to 40°F (-5 to 5°C);
4 hours minimum at 0 to 20°F (-20 to -5°C);
Step 10: Joint Cure Time
The joint must adequately cure prior to use (see "Joint Cure Schedule" table below). Required cure time depends on temperature, pipe diameter, and pressure application. The following table is based on the guidelines of ASTM D 2855, "Standard Practice for Making Solvent-Cemented Joints with Poly Vinyl Chloride (PVC) Pipe and Fittings". It is the user's responsibility and risk in determining that the joint has properly cured for handling, testing, and use.
Joint Cure Schedule
| 60°-100°F | 40°-60°F | 20°-40°F | 10°-20°F |
Nominal Pipe Size | Test Pressure 0-180 | Test Pressure 181-315 | Test pressure 0-180 | Test pressure 181-315 | Test pressure 0-180 | Test pressure 181-315 | Test pressure 0-180 | Test pressure 181-315 |
1/2" to 1-1/4" | 1 hr. | 6 hrs. | 2 hrs. | 12 hrs. | 6 hrs. | 36 hrs. | 8 hrs. | 48 hrs. |
1-1/2" to 3" | 2 hrs. | 12 hrs. | 4 hrs. | 24 hrs. | 12 hrs. | 72 hrs. | 16 hrs. | 96 hrs. |
3-1/2" to 5" | 6 hrs. | 18 hrs. | 12 hrs. | 36 hrs. | 36 hrs. | 4 days | 72 hrs. | 8 days |
6" to 8" | 8 hrs. | 24 hrs. | 16 hrs. | 48 hrs. | 3 days | 9 days | 4 days | 12 days |
NOTE: Extreme caution should be used when solvent cementing joints at temperatures below 10°F, and many variables exist at temperatures below 20°F. Relative humidity greater than 50% will increase required cure times specified. Consult solvent cement manufacturer for additional information.
THREADED CONNECTIONS
Threaded joints are used where piping system dismantling for occasional cleaning or modification is anticipated. Since threading reduces the effective wall thickness of pipe, pressure ratings of the pipe are reduced to one-half that of unthreaded pipe using solvent cement welded joints. Valves, however, have individual pressure ratings substantially different from that of pipe. As a result, no reduction in the valves specified pressure rating is necessary for threaded connections. Threaded systems should be made with Schedule 80 pipe only, threaded with an ANSI general purpose tapered pipe thread (NPT). Schedule 40 pipe should not be threaded. Use Schedule 40 Male Adapters solvent cement welded to Schedule 40 pipe.
WARNING: NOT FOR DISTRIBUTION OF COMPRESSED AIR OR GAS (see also, "Precautions & Warnings For All Installations").
SELECTION OF THREAD SEALANT
Threaded connections require application of a quality grade thread sealant to seal joint assembly.
WARNING: SOME PIPE JOINT COMPOUNDS OR PTFE PASTES MAY CONTAIN SUBSTANCES THAT COULD CAUSE STRESS CRACKING IN THERMOPLASTIC MATERIALS. Spears® Manufacturing Company recommends the use of Spears® BLUE 75™ thread sealant which has been tested for compatibility with Spears products. Please follow the sealant manufacturers' application/installation instructions. Choice of an appropriate thread sealant other than those listed above is at the discretion of the installer.
PREPARATION
For best results, installation should be made at temperatures between 40°F and 110°F.
All joint components should be inspected for any breaking, chipping, gouging or other visible damage before proceeding. All pipe and fittings should be removed from their packaging or containers and exposed to the installation environment for a minimum of one hour in order to thermally balance all components.
GENERAL PROCEDURE
Step 1: Apply Joint Sealant to the male thread.
Step 2: Assemble Joint by Hand
Threaded pipe and valves or fittings should be initially assembled "finger tight" (just enough to fully engage thread clearance).
Step 3: Strap Wrench Make-Up
Threaded plastic pipe and fitting components should always be installed using commercially available strap wrenches. Do not use conventional pipe wrenches which can damage plastic piping materials.
Apply strap wrench make-up of no more than one (1) to two (2) turns beyond finger tight thread engagement. Care should be taken in final positioning so as to avoid the need to "back-up" the wrenched assembly.
WARNING: THE SINGLE MOST COMMON CAUSE OF THREADED JOINT FAILURE IS OVER TIGHTENING. Tapered pipe threads produce radial stress in female fittings. Over tightening can exceed the stress limits of thermoplastic materials, resulting in split fittings. For extra protection, select Spears Stainless Steel Reinforced (SR) type female threaded adapters.
FLANGED CONNECTIONS
Flanges are used extensively for connections where removable system components are desired. Such includes periodic system servicing, anticipated system modification or add-on, and temporary component hookups. Flanges are also the standard connection for industrial butterfly valves and larger sizes of diaphragm valves.
WARNING: NOT FOR DISTRIBUTION OF COMPRESSED AIR OR GAS (see also, "Precautions & Warnings For All Installations").
PRESSURE RATINGS
Plastic pipe flanges are designed for system maximum internal pressures of 150 psi for water at 73°F (or as otherwise specified according to flange type and size). Pressure rating must be taken into consideration when using flanges with higher pressure rated components, such as pipe or valves.
GASKETS
Full faced, 1/8" thick elastomer gaskets with a Shore "A" Durometer of approximately 70 is recommended.
BOLT PATTERNS
Bolt patterns and number of bolt holes are the same as Class 150 metal flanges per ANSI B16.5.
BOLT TORQUE
Recommended Bolt torque requirements are shown below. Threads should be clean and well lubricated. Actual field conditions may require variations in these recommendations. CAUTION: UNNECESSARY OVER TORQUING WILL DAMAGE THE FLANGE.
Flange Size (in.) | Recommended Torque (ft. lbs.) |
1/2 - 1-1/2 | 12 |
2 - 4 | 25 |
5 | 30 |
6 - 8 | 40 |
10 | 64 |
12 | 95 |
14 - 24 | 110 |
TORQUE SEQUENCE
Bolts should be tightened IN 5 ft-lb increments using a 180° opposing pattern.
GENERAL PROCEDURE
Once a flange is attached to the pipe or valve, the method of joining two flanges is as follows:
Step 1: Piping runs joined to the flanges must be installed in with each other to avoid stress at the flange due to misalignment. Piping must also be secured and supported to prevent lateral movement which can create stress and damage the flange.
Step 2: With gasket in place, align the bolt holes of the mating flanges by rotating the ring into position. (Consideration should be given to alignment of One-Piece Flange prior to joining with pipe.)
Step 3: Insert all bolts, washers (two standard flat washers per bolt), and nuts.
Step 4: Make sure the faces of the mating surfaces are flush against gasket prior to bolting down the flanges.
Step 5: Tighten the nuts by hand until they are snug. Establish uniform pressure over the flange face by tightening the bolts in 5 ft-lb increments to the required bolt torque (see above) using a 180° opposing sequence. NOTE: Flange bolts may require re-torquing to specifications after initial pressure testing.
CAUTION: Care must be taken to avoid "bending" the flange when joining a Spears flange to a "raised face" flange, or a wafer-style valve. DO NOT use bolts to bring together improperly mated flanges or flanged ends on valves.
BARBED INSERT FITTING INSTALLATION
Standard Barbed Insert Fittings are designed for use with polyethylene pipe produced with average inside diameter dimensions as shown in ASTM Standards D 2104 and D 2239. Pipe is installed over Barbed Insert Fittings and connected using conventional gear operated hose clamps (see also, "Spiral Barb Fitting Installation" below).
WARNING: NOT FOR DISTRIBUTION OF COMPRESSED AIR OR GAS (see also, "Precautions & Warnings for All Product Installations").
WARNING: SOME LUBRICANTS, INCLUDING VEGETABLE OILS, ARE KNOWN TO CAUSE STRESS CRACKING IN THERMOPLASTIC MATERIALS. Water, a mild soap solution, or commercially available pipe gasket lubricant suitable for PVC and CPVC is recommended for use where lubrication is needed for installation. Choice of lubricant is at the discretion of the installer.
LAYING FLEXIBLE PIPE
When installing flexible lines, (a) snake line one foot or more per 100 linear feet, (b) cold water should be run through lines prior to backfilling to permit pipe to contract, (c) care should be taken to prevent large and sharp-edged rocks from being in position to crush pipe.
ADAPTER CONNECTION
For attachment to previously installed metallic systems or threaded fixtures, the threaded insert adapter is utilized. Apply thread sealant to the threaded end of adapter and tighten into female connection (see also installation instructions for "Threaded Connections").
GENERAL PROCEDURE
Step 1: Cut pipe square to desired length with hacksaw or knife.
Step 2: Slip stainless steel clamps over end of pipe far enough to allow free installation of pipe on fitting.
Step 3: Install Pipe on Fitting
Use plain water or soapy water as lubricant on fitting and pipe I.D. DO NOT use oil or detergent on any fittings. Slip pipe over insert serrations until pipe end is fully seated at base of insert.
Step 4: Position clamp over pipe and insert, tighten securely.
SPIRAL BARB FITTING INSTALLATION
spiral Barb fittings are designed for use with 1/2" (0.490) polyethylene irrigation hose and do not require steel clamps. Install with a twisting motion to fully engage barbs.