Let-Lok® Tube Fittings
94Pages

COMPRESSION TUBE FITTINGS

LET-LOK® TUBE FITTINGS DESCRIPTION The LET-LOK® tube fitting is a mechanism used both to seal and to grip tubing. The mechanical advantage and geometry of this kind of fitting produces a leak-tight assembly. LET-LOK® HOW DOES IT WORK? The HAM-LET GROUP has produced high quality tube and pipe fittings in various materials for high pressure applications since its establishment in 1950. To assemble, simply insert the tube into the complete assembly until the tube bottoms-out against the shoulder of the fitting body (1). The two ferrules are driven forward between the nut (4) and fitting body...

LET-LOK® FITTINGS INSTALLATION INSTRUCTIONS REASSEMBLY INSTRUCTIONS INSPECTION GAUGE LET-LOK® connections may be disconnected and remade repeatedly, without the loss of the leaktight seal. 1. Before disconnecting, mark the position of the nut in relation to the fitting body. 2.To reassemble, use a wrench to tighten the nut to the original position. 3.Tighten slightly with a wrench until a slight rise in torque is felt. Use: This is a “No-Go” gauge and should be used as follows: TUBE CUTTING Insert the tubing into the LET-LOK® fitting. Check that the tube rests firmly on the fitting shoulder...

LET-LOK® FITTINGS INSTALLATION INSTRUCTIONS TUBING DATA FOR LET-LOK® FITTINGS PHYSICAL DIFFERENCES AND MARKINGS LET-LOK® METRIC FITTINGS: Tee & Elbow (see Fig. 1) Body marked: MM Straight Connectors: (see Fig. 2) Body: Stepped shoulder Marked: LET-LOK® 316 AV1(2) Nut: (see Figs.1 & 2) Stepped shoulder Marked: LET-LOK® 316 6M(1) SD8(2) LET-LOK® 316 AV1 In order to assure maximum fitting reliability and performance, great care should be given when selecting the tubing for each application. TUBE SELECTION Four variables must be considered when ordering tube for use with LET-LOK® fittings: 1....

TABLE 1: STAINLESS STEEL INCH TUBING Annealed 304 or 316 stainless steel tubing complying with ASTM A213, A269 or equivalent specifications. For metal temp. from -20°F - 100°F (-29°C - 37°C). Suggested ordering information: Fully annealed high quality (Type 304 or 316) stainless steel hydraulic tubing ASTM A269 or A213 or equivalent, seamless or welded and drawn with a hardness of 90HRB (200HV) or less. Tubing should be without scratches and suitable for flaring and bending. TABLE 2: STAINLESS STEEL METRIC TUBING Annealed 304 or 316 stainless steel tubing complying with ASTM A213, A269 or...

TABLE 3: COPPER TUBING WALL THICKNESS OF TUBE IN INCH Annealed copper seamless tubing complying with ASTM B68 and AsTm B75 specified in temper designation 060. Based on ultimate tensile strength of 30,000 psi (2067 bar). For metal temperatures from -20°C to 37°C). Suggested ordering information: High quality soft annealed seamless copper tubing ASTM B75 or equivalent. TABLE 4: FACTORS USED TO DETERMINE ALLOWABLE PRESSURE AT HIGHER TEMPERATURES Gases are characterized by small molecules, which can escape through the smallest leak path. For gas applications, we recommend to select tubing with...

Pressure Ratings for HAM-LET Tube Fittings Pressure Ratings for End Fittings per SAE J1926 (LOB) Surrounding Temperature To ensure leak-tight systems, it is important to carefully select Pressure ratings are based on SAE J1926 at surrounding tem- high-quality tubing (see page 11 - allowable working pressure). perature. Pipe End Thread (NPT and ISO 7) Pressure Ratings Allowable pressure for male and female tapered pipe thread ends: Stainless Steel 316 and Brass. TABLE 6: PRESSURE RATINGS HAM-LET ADVANCED CONTROL TECHNOLOGY

TUBE SOCKET WELD UNION 768 LW MALE PIPE WELD ELBOW 769 LN TUBE SOCKET WELD ELBOW 769 LW

MALE ADAPTER TUBE TO PIPE 739 LMG WELD ADAPTER TUBE TO PIPE 739 LN MALE ADAPTER 739 LMOB CONNECTORS UNION CROSS 7102 L UNION DIELECTRIC 762 L Dielectric FEMALE ADAPTER TUBE TO PIPE 739 LF MALE ADAPTER TUBE TO PIPE 739 LM MALE ADAPTER TUBE TO PIPE 739 LMR PARALLEL THREADS SEALING SUPER DUPLEX 2507 CONNECTOR STOP COLLAR LET-LOK® MATERIAL DESCRIPTION All orders should include material description and ordering information (see product table). HAM-LET ADVANCED CONTROL TECHNOLOGY

METRIC INCHMETRIC INCH Ordering FERRULE SETS All LET-LOK® Ferrules are available as sets. Ferrule sets simplify stocking and assembly. Ferrule sets prevent damage of single ferrules during shipping. The back and front ferrules are arranged as pairs in the set; ready for easy assembly. Note: Can be supplied also with Nuts. Example: 760LNS SS 1/4 Ordering Information for Ferrule Sets The O.D. size is always the first to be described B = Brass M = Alloy 400 HC = Alloy C-276 T = PTFE Ferrules Material Dimensions are for reference only, and are subject to change without notice. 16 LET-LOK...

METRIC INCH Ordering METRIC Ordering Information "D" - Dimension is minimum opening. Dimensions are for reference only, and are subject to change without notice. HAM-LET ADVANCED CONTROL TECHNOLOGY

TUBE (METRIC) TO TUBE (METRIC) * Including low friction paste, see page 91 “D” - Dimension is minimum opening. Dimensions are for reference only, and are subject to change without notice. 18 LET-LtnC COMPRESSION TUBE FITTINGS

TUBE (METRIC) TO TUBE (METRIC) TUBE (METRIC) TO TUBE (INCH) Ordering Information * Including low friction paste, see page 91 “D” - Dimension is minimum opening. Dimensions are for reference only, and are subject to change without notice. Cont’d next page HAM-LET ADVANCED CONTROL TECHNOLOGY

763 L REDUCING UNION (Cont’d)TUBE (INCH) TO TUBE (INCH) Ordering Information

* Including low friction paste, see page 91 Dimensions are for reference only, and are subject to change without notice. “D” - Dimension is minimum opening.

ALL TUBE (METRIC) Ordering Information Information Tube O.D. Tube O.D Wrench Flat “D” - Dimension is minimum opening. Dimensions are for reference only, and are subject to change without notice. Cont’d next page * Including low friction paste, see page 91 LET-LOK COMPRESSION TUBE FITTINGS