{"id":174,"date":"2026-07-15T07:54:59","date_gmt":"2026-07-15T07:54:59","guid":{"rendered":"https:\/\/onestepblowmoldingmachine.com\/what-are-the-common-faults-of-isbm-machines-and-how-to-fix-them\/"},"modified":"2026-07-15T07:54:59","modified_gmt":"2026-07-15T07:54:59","slug":"what-are-the-common-faults-of-isbm-machines-and-how-to-fix-them","status":"publish","type":"post","link":"https:\/\/onestepblowmoldingmachine.com\/ru\/what-are-the-common-faults-of-isbm-machines-and-how-to-fix-them\/","title":{"rendered":"What Are the Common Faults of ISBM Machines and How to Fix Them?"},"content":{"rendered":"<nav aria-label=\"\u0425\u043b\u0435\u0431\u043d\u044b\u0435 \u043a\u0440\u043e\u0448\u043a\u0438\" style=\"margin-bottom:18px;font-size:13px;color:#666;\"><a href=\"\/ru\/\" style=\"color:#0066cc;text-decoration:none;\">\u0414\u043e\u043c<\/a> &rsaquo; <a href=\"\/ru\/products\/isbm-machines\/\" style=\"color:#0066cc;text-decoration:none;\">ISBM Machines<\/a> &rsaquo; <span>Common ISBM Machine Faults and How to Fix Them<\/span><\/nav>\n<h2 style=\"font-size:28px;color:#1a2e44;margin-bottom:10px;\">What Are the Common Faults of ISBM Machines and How to Fix Them?<\/h2>\n<p style=\"font-size:16px;line-height:1.8;color:#333;margin-bottom:24px;\">Unplanned downtime on an injection stretch blow molding machine is expensive \u2014 not just in lost production, but in the cost of scrap material, energy wasted heating up a stopped machine, and the knock-on effects through downstream filling and packaging operations. A well-maintained ISBM machine with a trained operator who can rapidly identify and resolve faults is a competitive advantage.<\/p>\n<p style=\"font-size:16px;line-height:1.8;color:#333;margin-bottom:24px;\">This fault diagnosis guide covers the ten most commonly encountered ISBM faults, organised by process stage, with the root cause analysis, diagnostic steps, and corrective actions needed to return the machine to production as quickly as possible. A preventive maintenance schedule is also provided to help avoid recurrence.<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/onestepblowmoldingmachine.com\/wp-content\/uploads\/2026\/07\/isbm-machine-2.webp\" alt=\"ISBM machine control panel showing fault alarm state during troubleshooting\" style=\"width:100%;max-width:100%;height:auto;border-radius:8px;margin-bottom:28px;display:block;\" \/><\/p>\n<h2 style=\"font-size:24px;color:#1a2e44;border-left:4px solid #0066cc;padding-left:12px;margin-top:36px;\">Fault Category Overview<\/h2>\n<div style=\"overflow-x:auto;-webkit-overflow-scrolling:touch;margin-bottom:28px;\">\n<table style=\"width:100%;border-collapse:collapse;min-width:480px;\">\n<thead>\n<tr style=\"background-color:#1a2e44;\">\n<th style=\"color:white;background-color:#1a2e44;padding:12px 14px;text-align:left;font-size:14px;\">Category<\/th>\n<th style=\"color:white;background-color:#1a2e44;padding:12px 14px;text-align:left;font-size:14px;\">Faults Covered<\/th>\n<th style=\"color:white;background-color:#1a2e44;padding:12px 14px;text-align:left;font-size:14px;\">Primary Impact<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"background-color:#f8f9fa;\">\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Injection \/ Preform<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Short shot, gate defects, black specks, hot runner drool<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Scrap rate, material waste<\/td>\n<\/tr>\n<tr>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Conditioning<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Pearlescence (PP), haze (PET), neck distortion<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Visual rejection, mechanical failure<\/td>\n<\/tr>\n<tr style=\"background-color:#f8f9fa;\">\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Stretch-Blow<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Wall thickness variation, gate puncture, incomplete fill<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Structural failure, scrap<\/td>\n<\/tr>\n<tr>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Ejection \/ Mold<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Mold sticking, bottle deformation at eject<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Downtime, mold damage<\/td>\n<\/tr>\n<tr style=\"background-color:#f8f9fa;\">\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Machine \/ Electrical<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Pressure and temperature alarms, servo faults<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Production stop<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<h2 style=\"font-size:24px;color:#1a2e44;border-left:4px solid #dc3545;padding-left:12px;margin-top:36px;\">Fault 1 \u2014 Preform Short Shot or Incomplete Fill<\/h2>\n<div style=\"background-color:#fef2f2;border-radius:8px;padding:18px 20px;margin-bottom:20px;\"><strong style=\"color:#dc3545;\">Symptom:<\/strong> Preforms exiting the injection station are visibly incomplete \u2014 missing material in the neck, body, or gate area. Preform is underweight on scale check.<\/div>\n<p style=\"font-size:16px;line-height:1.8;color:#333;margin-bottom:12px;\"><strong>Root Causes:<\/strong><\/p>\n<ul style=\"padding-left:22px;line-height:2;font-size:15px;color:#333;margin-bottom:12px;\">\n<li>Shot size set too small \u2014 insufficient material metered<\/li>\n<li>Back pressure too low \u2014 poor melt uniformity, poor shot repeatability<\/li>\n<li>Injection speed too slow \u2014 material solidifies before cavity is full<\/li>\n<li>Hot runner gate partially blocked \u2014 reduced flow to affected cavity<\/li>\n<li>Material feed interruption \u2014 bridging in hopper or inadequate drying<\/li>\n<\/ul>\n<p style=\"font-size:16px;line-height:1.8;color:#333;margin-bottom:12px;\"><strong>Corrective Actions:<\/strong><\/p>\n<ul style=\"padding-left:22px;line-height:2;font-size:15px;color:#333;margin-bottom:20px;\">\n<li>Verify shot size setting against calculated preform weight; increase if short<\/li>\n<li>Increase injection speed in 10% increments, monitoring for flash<\/li>\n<li>Check hot runner temperature at each zone; raise sticking zone by 5\u00b0C<\/li>\n<li>Purge barrel with 3\u20135 purge shots; inspect nozzle tip for cold plug<\/li>\n<li>Check hopper level and dryer operation; verify resin flow at throat<\/li>\n<\/ul>\n<h2 style=\"font-size:24px;color:#1a2e44;border-left:4px solid #dc3545;padding-left:12px;margin-top:36px;\">Fault 2 \u2014 Gate Blush, Stringing, or Gate Vestige Problems<\/h2>\n<div style=\"background-color:#fef2f2;border-radius:8px;padding:18px 20px;margin-bottom:20px;\"><strong style=\"color:#dc3545;\">Symptom:<\/strong> Visible discolouration, hazing, or raised string of material at the gate point on the base of preform or bottle. Gate vestige (pip) too long or sharp.<\/div>\n<p style=\"font-size:16px;line-height:1.8;color:#333;margin-bottom:12px;\"><strong>Root Causes and Fixes:<\/strong><\/p>\n<div style=\"overflow-x:auto;-webkit-overflow-scrolling:touch;margin-bottom:24px;\">\n<table style=\"width:100%;border-collapse:collapse;min-width:480px;\">\n<thead>\n<tr style=\"background-color:#0066cc;\">\n<th style=\"color:white;background-color:#0066cc;padding:11px 14px;text-align:left;font-size:14px;\">Defect<\/th>\n<th style=\"color:white;background-color:#0066cc;padding:11px 14px;text-align:left;font-size:14px;\">Cause<\/th>\n<th style=\"color:white;background-color:#0066cc;padding:11px 14px;text-align:left;font-size:14px;\">Fix<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"background-color:#f8f9fa;\">\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:13px;\">Gate blush (halo)<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:13px;\">Gate tip too cold; material solidifying at gate<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:13px;\">Raise gate zone temperature 3-5\u00b0C<\/td>\n<\/tr>\n<tr>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:13px;\">Stringing \/ hairing<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:13px;\">Gate tip too hot; material drools on retract<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:13px;\">Reduce gate zone temperature; add screw decompression<\/td>\n<\/tr>\n<tr style=\"background-color:#f8f9fa;\">\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:13px;\">Long gate vestige<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:13px;\">Gate tip wear; tip geometry incorrect<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:13px;\">Inspect and replace hot runner gate tip<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<h2 style=\"font-size:24px;color:#1a2e44;border-left:4px solid #dc3545;padding-left:12px;margin-top:36px;\">Fault 3 \u2014 Uneven Wall Thickness in Blown Bottle<\/h2>\n<div style=\"background-color:#fef2f2;border-radius:8px;padding:18px 20px;margin-bottom:20px;\"><strong style=\"color:#dc3545;\">Symptom:<\/strong> Cut-section inspection or ultrasonic measurement reveals wall thickness significantly heavier in one zone (typically base or shoulder) and correspondingly thin in another. Top-load test failure. Bottle feels asymmetric.<\/div>\n<p style=\"font-size:16px;line-height:1.8;color:#333;margin-bottom:12px;\"><strong>Root Causes:<\/strong><\/p>\n<ul style=\"padding-left:22px;line-height:2;font-size:15px;color:#333;margin-bottom:12px;\">\n<li>Preform body temperature non-uniform \u2014 hot spots and cold spots<\/li>\n<li>Stretch rod not centered on gate \u2014 eccentric axial stretch<\/li>\n<li>Rod reaching full stroke before pre-blow initiates \u2014 base pile-up<\/li>\n<li>Non-uniform conditioning zone temperatures across preform zones<\/li>\n<\/ul>\n<p style=\"font-size:16px;line-height:1.8;color:#333;margin-bottom:12px;\"><strong>Corrective Actions:<\/strong><\/p>\n<ul style=\"padding-left:22px;line-height:2;font-size:15px;color:#333;margin-bottom:20px;\">\n<li>Measure preform temperature profile with IR gun at multiple zones \u2014 adjust conditioning zone setpoints to equalise<\/li>\n<li>Check rod alignment: use an alignment indicator to verify rod tip centres to gate within 0.3mm<\/li>\n<li>Adjust pre-blow timing to initiate earlier \u2014 reduce delay if base is too heavy<\/li>\n<li>If thick base persists despite correct temperatures, the rod stroke may be too short \u2014 increase rod stroke setting<\/li>\n<\/ul>\n<h2 style=\"font-size:24px;color:#1a2e44;border-left:4px solid #dc3545;padding-left:12px;margin-top:36px;\">Fault 4 \u2014 Whitening or Haze in PET Bottle Body<\/h2>\n<div style=\"background-color:#fef2f2;border-radius:8px;padding:18px 20px;margin-bottom:20px;\"><strong style=\"color:#dc3545;\">Symptom:<\/strong> Bottle body appears cloudy, white-streaked, or has a &#8220;frosted&#8221; appearance instead of the expected crystal clarity.<\/div>\n<p style=\"font-size:16px;line-height:1.8;color:#333;margin-bottom:12px;\"><strong>Two distinct root causes must be distinguished:<\/strong><\/p>\n<div style=\"display:flex;flex-wrap:wrap;gap:16px;margin-bottom:20px;\">\n<div style=\"flex:1;min-width:240px;background:#fff3cd;border-left:4px solid #e67e00;padding:16px;border-radius:4px;\"><strong style=\"color:#e67e00;\">Cause A: Thermal Haze<\/strong><\/p>\n<p style=\"font-size:14px;color:#444;margin-top:8px;line-height:1.7;\">Preform body too hot at conditioning station \u2014 cold crystallinity forms before blow. Haze pattern uniform across bottle body. Fix: reduce conditioning temperature 5\u00b0C at a time; check heating element output; verify cycle time is not too long (preform dwelling too long in conditioning).<\/p>\n<\/div>\n<div style=\"flex:1;min-width:240px;background:#fff3cd;border-left:4px solid #e67e00;padding:16px;border-radius:4px;\"><strong style=\"color:#e67e00;\">Cause B: Moisture Haze<\/strong><\/p>\n<p style=\"font-size:14px;color:#444;margin-top:8px;line-height:1.7;\">Resin moisture too high \u2014 hydrolytic degradation during injection produces low-molecular-weight oligomers that scatter light. Haze often accompanied by brittleness and reduced bottle weight. Fix: extend drying time; check dryer dew point; verify Karl Fischer moisture reading below 50 ppm.<\/p>\n<\/div>\n<\/div>\n<h2 style=\"font-size:24px;color:#1a2e44;border-left:4px solid #dc3545;padding-left:12px;margin-top:36px;\">Fault 5 \u2014 Pearlescence in PP Bottles<\/h2>\n<div style=\"background-color:#fef2f2;border-radius:8px;padding:18px 20px;margin-bottom:20px;\"><strong style=\"color:#dc3545;\">Symptom:<\/strong> PP bottle shows iridescent, pearl-like optical effect \u2014 appears milky-shiny rather than clear. Particularly prominent at shoulder and base.<\/div>\n<p style=\"font-size:16px;line-height:1.8;color:#333;margin-bottom:12px;\"><strong>Root Cause:<\/strong> Preform body temperature entering the blow station is too high for the specific PP grade being processed \u2014 the polymer has begun to form unoriented spherulitic crystallites before orientation can occur. PP&#8217;s orientation window is very narrow (approximately 125\u2013140\u00b0C), and exceeding the upper bound causes this classic pearlescence defect.<\/p>\n<p style=\"font-size:16px;line-height:1.8;color:#333;margin-bottom:12px;\"><strong>Corrective Actions:<\/strong><\/p>\n<ul style=\"padding-left:22px;line-height:2;font-size:15px;color:#333;margin-bottom:20px;\">\n<li>Reduce conditioning station temperature by 3\u20135\u00b0C increments<\/li>\n<li>Check that preform neck cooling is functioning \u2014 hot neck can absorb heat back into body<\/li>\n<li>Verify PP grade: use random copolymer PP with nucleating agent for clarity applications; homopolymer PP will always pearl<\/li>\n<li>Reduce conditioning dwell time if excess heat is accumulating from retained injection energy<\/li>\n<\/ul>\n<h2 style=\"font-size:24px;color:#1a2e44;border-left:4px solid #dc3545;padding-left:12px;margin-top:36px;\">Fault 6 \u2014 Stretch Rod Marks or Gate Puncture<\/h2>\n<div style=\"background-color:#fef2f2;border-radius:8px;padding:18px 20px;margin-bottom:20px;\"><strong style=\"color:#dc3545;\">Symptom:<\/strong> Visible rod mark (linear scratch\/groove down gate area of bottle) or complete puncture hole at gate. High scrap rate, possible mold cavity contamination from blown fragments.<\/div>\n<p style=\"font-size:16px;line-height:1.8;color:#333;margin-bottom:12px;\"><strong>Root Causes and Corrective Actions:<\/strong><\/p>\n<ul style=\"padding-left:22px;line-height:2;font-size:15px;color:#333;margin-bottom:20px;\">\n<li><strong>Pre-blow pressure too low:<\/strong> rod contacts unprotected gate area and forces it \u2014 increase pre-blow pressure by 1\u20132 bar<\/li>\n<li><strong>Pre-blow delayed too late:<\/strong> rod tip reaches gate before air contacts preform \u2014 advance pre-blow initiation timing relative to rod start<\/li>\n<li><strong>Preform too cold:<\/strong> material is insufficiently mobile to stretch away from rod tip \u2014 increase conditioning temperature<\/li>\n<li><strong>Rod tip condition:<\/strong> worn, chipped, or rough rod tip causes marking even when process is otherwise correct \u2014 inspect and replace stretch rod tip<\/li>\n<\/ul>\n<h2 style=\"font-size:24px;color:#1a2e44;border-left:4px solid #dc3545;padding-left:12px;margin-top:36px;\">Fault 7 \u2014 Mold Sticking or Difficult Part Ejection<\/h2>\n<div style=\"background-color:#fef2f2;border-radius:8px;padding:18px 20px;margin-bottom:20px;\"><strong style=\"color:#dc3545;\">Symptom:<\/strong> Bottle does not release cleanly from blow mold on mold open. Bottle tears, deforms, or requires manual removal. Production stops on every cycle.<\/div>\n<p style=\"font-size:16px;line-height:1.8;color:#333;margin-bottom:12px;\"><strong>Root Causes and Corrective Actions:<\/strong><\/p>\n<ul style=\"padding-left:22px;line-height:2;font-size:15px;color:#333;margin-bottom:20px;\">\n<li><strong>Mold temperature too warm:<\/strong> bottle has not cooled sufficiently before mold opens \u2014 lower mold temperature or increase blow time; extend cooling phase<\/li>\n<li><strong>Bottle wall too thin:<\/strong> insufficient rigidity for clean ejection \u2014 investigate wall thickness distribution<\/li>\n<li><strong>Mold surface condition:<\/strong> rough parting line or worn draft angles create mechanical lock \u2014 polish mold cavity; verify draft angles minimum 1\u00b0<\/li>\n<li><strong>Mold venting blocked:<\/strong> air cannot escape during ejection, creating suction \u2014 clean vent channels; verify vent depth (typically 0.015\u20130.03mm)<\/li>\n<li><strong>Ejector pin worn or misaligned:<\/strong> check ejector pin travel and alignment; replace worn pins<\/li>\n<\/ul>\n<h2 style=\"font-size:24px;color:#1a2e44;border-left:4px solid #dc3545;padding-left:12px;margin-top:36px;\">Fault 8 \u2014 Hot Runner Drool or Black Specks<\/h2>\n<p><img decoding=\"async\" src=\"https:\/\/onestepblowmoldingmachine.com\/wp-content\/uploads\/2026\/07\/one-step-Injection-stretch-blow-machine-molds-3.webp\" alt=\"ISBM machine hot runner system inspection for drool and black speck defects\" style=\"width:100%;max-width:100%;height:auto;border-radius:8px;margin-bottom:24px;display:block;\" \/><\/p>\n<div style=\"background-color:#fef2f2;border-radius:8px;padding:18px 20px;margin-bottom:20px;\"><strong style=\"color:#dc3545;\">Symptom:<\/strong> Material drooling from gate between cycles (hot runner drool); or dark\/black particles visible in preform or bottle body (black specks).<\/div>\n<ul style=\"padding-left:22px;line-height:2;font-size:15px;color:#333;margin-bottom:20px;\">\n<li><strong>Drool:<\/strong> Hot runner gate tip too hot \u2014 reduce gate zone temperature; add screw decompression stroke<\/li>\n<li><strong>Black specks \u2014 degraded material:<\/strong> material residence time in barrel or hot runner manifold too long \u2014 reduce stock temperature; increase injection frequency; purge barrel with commodity-grade PET before production restart<\/li>\n<li><strong>Black specks \u2014 contamination:<\/strong> check screw, barrel, and non-return valve for wear-through of chrome plating or corrosion deposits \u2014 inspect and replace worn components<\/li>\n<\/ul>\n<h2 style=\"font-size:24px;color:#1a2e44;border-left:4px solid #dc3545;padding-left:12px;margin-top:36px;\">Fault 9 \u2014 Machine Alarm: Pressure Out of Range<\/h2>\n<div style=\"background-color:#fef2f2;border-radius:8px;padding:18px 20px;margin-bottom:20px;\"><strong style=\"color:#dc3545;\">Symptom:<\/strong> Control system generates alarm for low blow pressure, high hydraulic pressure, or pneumatic pressure below setpoint. Machine stops or enters fault state.<\/div>\n<div style=\"overflow-x:auto;-webkit-overflow-scrolling:touch;margin-bottom:20px;\">\n<table style=\"width:100%;border-collapse:collapse;min-width:480px;\">\n<thead>\n<tr style=\"background-color:#1a2e44;\">\n<th style=\"color:white;background-color:#1a2e44;padding:11px 14px;text-align:left;font-size:14px;\">Alarm Type<\/th>\n<th style=\"color:white;background-color:#1a2e44;padding:11px 14px;text-align:left;font-size:14px;\">First Check<\/th>\n<th style=\"color:white;background-color:#1a2e44;padding:11px 14px;text-align:left;font-size:14px;\">Next Step<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"background-color:#f8f9fa;\">\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:13px;\">Low blow pressure alarm<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:13px;\">Booster compressor operating? HP air pressure gauge reading?<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:13px;\">Check booster compressor motor, inlet air filter, pressure switch setting<\/td>\n<\/tr>\n<tr>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:13px;\">High hydraulic pressure alarm<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:13px;\">Is mold closed fully? Is there debris in mold parting line?<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:13px;\">Check hydraulic oil level and temperature; inspect relief valve setting<\/td>\n<\/tr>\n<tr style=\"background-color:#f8f9fa;\">\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:13px;\">Low LP pneumatic alarm<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:13px;\">Compressor running? Service regulator setting?<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:13px;\">Check for air leaks at fittings; replace worn seals on cylinders<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<h2 style=\"font-size:24px;color:#1a2e44;border-left:4px solid #dc3545;padding-left:12px;margin-top:36px;\">Fault 10 \u2014 Bottle Fails Top-Load or Collapses<\/h2>\n<div style=\"background-color:#fef2f2;border-radius:8px;padding:18px 20px;margin-bottom:20px;\"><strong style=\"color:#dc3545;\">Symptom:<\/strong> Bottle collapses or buckles under applied top-load force below the specified minimum. Pallet-stacked bottles deform in distribution. Customer returns for crushed bottles.<\/div>\n<p style=\"font-size:16px;line-height:1.8;color:#333;margin-bottom:12px;\"><strong>Root Causes and Corrective Actions:<\/strong><\/p>\n<ul style=\"padding-left:22px;line-height:2;font-size:15px;color:#333;margin-bottom:20px;\">\n<li><strong>Insufficient biaxial orientation:<\/strong> ASR and\/or HSR below target \u2014 verify stretch ratio settings against design; measure wall thickness distribution<\/li>\n<li><strong>Preform temperature too low or too high:<\/strong> both extremes produce weaker orientation \u2014 verify conditioning temperature is within the 90\u2013105\u00b0C window (PET)<\/li>\n<li><strong>Wall too thin overall:<\/strong> preform design or resin IV may have changed \u2014 verify preform weight and IV of resin lot<\/li>\n<li><strong>Hot-fill or post-fill temperature:<\/strong> if product is hot-filled above 55\u00b0C, standard ISBM PET without thermal crystallisation will soften \u2014 this is a design issue, not a machine fault<\/li>\n<\/ul>\n<h2 style=\"font-size:24px;color:#1a2e44;border-left:4px solid #0066cc;padding-left:12px;margin-top:36px;\">Preventive Maintenance Schedule<\/h2>\n<div style=\"overflow-x:auto;-webkit-overflow-scrolling:touch;margin-bottom:28px;\">\n<table style=\"width:100%;border-collapse:collapse;min-width:480px;\">\n<thead>\n<tr style=\"background-color:#1a2e44;\">\n<th style=\"color:white;background-color:#1a2e44;padding:12px 14px;text-align:left;font-size:14px;\">Frequency<\/th>\n<th style=\"color:white;background-color:#1a2e44;padding:12px 14px;text-align:left;font-size:14px;\">Task<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr style=\"background-color:#f8f9fa;\">\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\" rowspan=\"3\">Daily<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Check oil level in hydraulic reservoir and lubrication system<\/td>\n<\/tr>\n<tr style=\"background-color:#f8f9fa;\">\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Verify chilled water supply temperature and flow rate<\/td>\n<\/tr>\n<tr style=\"background-color:#f8f9fa;\">\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Inspect mold cavity surfaces and gate area for deposits; clean with approved cloth<\/td>\n<\/tr>\n<tr>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\" rowspan=\"3\">Weekly<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Clean hopper and dryer filters<\/td>\n<\/tr>\n<tr>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Inspect stretch rod for wear, scoring, or misalignment<\/td>\n<\/tr>\n<tr>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Check all safety interlock switches for function<\/td>\n<\/tr>\n<tr style=\"background-color:#f8f9fa;\">\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\" rowspan=\"3\">Monthly<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Replace hydraulic oil filter; sample oil for particle analysis<\/td>\n<\/tr>\n<tr style=\"background-color:#f8f9fa;\">\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Grease all specified lubrication points per machine manual<\/td>\n<\/tr>\n<tr style=\"background-color:#f8f9fa;\">\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Inspect hot runner heater zones for resistance drift; replace heaters showing deviation &gt;10%<\/td>\n<\/tr>\n<tr>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\" rowspan=\"2\">Quarterly<\/td>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Full mold disassembly and cleaning; inspect cavity polish and vents<\/td>\n<\/tr>\n<tr>\n<td style=\"padding:10px 14px;border-bottom:1px solid #e0e0e0;font-size:14px;\">Replace screw barrel temperature barrel zone thermocouples showing drift<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<\/div>\n<p style=\"font-size:16px;line-height:1.8;color:#333;margin-bottom:24px;\">For <a href=\"\/ru\/products\/isbm-machines\/\" style=\"color:#0066cc;text-decoration:underline;\">ISBM machines<\/a> with persistent fault patterns not resolved by the above corrective actions, contact our technical support team. We provide fault logs analysis, remote diagnostic support, and on-site service visits for all machine models we supply. <a href=\"\/ru\/contact-us\/\" style=\"color:#0066cc;text-decoration:underline;\">Submit your fault details here for priority support<\/a>.<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/onestepblowmoldingmachine.com\/wp-content\/uploads\/2026\/07\/isbm-machine-factory-2.webp\" alt=\"ISBM machine factory service area showing technician performing preventive maintenance\" style=\"width:100%;max-width:100%;height:auto;border-radius:8px;margin-bottom:28px;display:block;\" \/><\/p>\n<h2 style=\"font-size:24px;color:#1a2e44;border-left:4px solid #0066cc;padding-left:12px;margin-top:36px;\">Frequently Asked Questions<\/h2>\n<details style=\"border:1px solid #dde4ec;border-radius:6px;margin-bottom:10px;\">\n<summary style=\"padding:14px 16px;cursor:pointer;font-weight:600;font-size:15px;color:#1a2e44;background:#f5f8fc;border-radius:6px;list-style:none;\">How do I differentiate between a material problem and a machine problem when a fault appears?<\/summary>\n<div style=\"padding:14px 16px;font-size:15px;line-height:1.8;color:#444;\">Trial a new bag of pre-dried resin with a controlled lot number. If the fault disappears, the cause is material-related (moisture, IV variation, contamination). If the fault persists with new resin, the cause is machine or tooling related. Always change one variable at a time and document the result.<\/div>\n<\/details>\n<details style=\"border:1px solid #dde4ec;border-radius:6px;margin-bottom:10px;\">\n<summary style=\"padding:14px 16px;cursor:pointer;font-weight:600;font-size:15px;color:#1a2e44;background:#f5f8fc;border-radius:6px;list-style:none;\">Can I run the ISBM machine with one cavity blocked if a gate tip fails?<\/summary>\n<div style=\"padding:14px 16px;font-size:15px;line-height:1.8;color:#444;\">Most machines can run with a blocked cavity using a dedicated blocking plug to seal that hot runner gate. Output drops proportionally. Ensure the machine control system has the capability to track and discard output from affected positions, and verify that running with a blocked cavity does not cause excessive pressure on remaining cavities or thermal imbalance in the hot runner manifold.<\/div>\n<\/details>\n<details style=\"border:1px solid #dde4ec;border-radius:6px;margin-bottom:10px;\">\n<summary style=\"padding:14px 16px;cursor:pointer;font-weight:600;font-size:15px;color:#1a2e44;background:#f5f8fc;border-radius:6px;list-style:none;\">Why does my ISBM machine run well on the morning shift but produce defects in the afternoon?<\/summary>\n<div style=\"padding:14px 16px;font-size:15px;line-height:1.8;color:#444;\">This is a classic thermal drift symptom. As ambient temperature in the plant rises through the day, chilled water supply may warm slightly, cooling of the mold becomes less effective, and conditioning zone temperatures may drift. Check chilled water supply temperature throughout the day; the setpoint temperature at the chiller may need to be lowered in warm seasons. Also check that the conditioning heater PID control is maintaining accurate setpoints rather than drifting with ambient changes.<\/div>\n<\/details>\n<div style=\"background-color:#1a2e44;color:white;border-radius:10px;padding:28px 24px;margin-top:40px;text-align:center;\">\n<h3 style=\"color:white;font-size:22px;margin-bottom:12px;\">Recurring ISBM Machine Fault? Get Expert Diagnosis.<\/h3>\n<p style=\"color:#cde;font-size:15px;margin-bottom:20px;line-height:1.7;\">Describe the defect, your current parameters, and the resin you are using \u2014 our process engineers will diagnose remotely in most cases.<\/p>\n<p><a href=\"\/ru\/contact-us\/\" style=\"background-color:#f0a500;color:#1a2e44;padding:13px 32px;border-radius:6px;text-decoration:none;font-weight:700;font-size:16px;display:inline-block;\">Submit a Fault Report<\/a><\/div>\n<p><script type=\"application\/ld+json\">{\n    \"@context\": \"https:\\\/\\\/schema.org\",\n    \"@graph\": [\n        {\n            \"@type\": \"Article\",\n            \"headline\": \"What Are the Common Faults of ISBM Machines and How to Fix Them?\",\n            \"description\": \"Comprehensive fault diagnosis guide for injection stretch blow molding machines covering 10 common faults, root causes, corrective actions, and a preventive maintenance schedule.\",\n            \"author\": {\n                \"@type\": \"Organization\",\n                \"name\": \"Ever-Power ISBM Machines\"\n            }\n        },\n        {\n            \"@type\": \"FAQPage\",\n            \"mainEntity\": [\n                {\n                    \"@type\": \"Question\",\n                    \"name\": \"How do I differentiate between a material problem and a machine problem?\",\n                    \"acceptedAnswer\": {\n                        \"@type\": \"Answer\",\n                        \"text\": \"Trial a new bag of pre-dried resin. 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Unplanned downtime on an injection stretch blow molding machine is expensive \u2014 not just in lost production, but in the cost of scrap material, energy wasted heating up [&hellip;]<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_et_pb_use_builder":"","_et_pb_old_content":"","_et_gb_content_width":"","footnotes":""},"categories":[125],"tags":[54,149,148,146,147],"class_list":["post-174","post","type-post","status-publish","format-standard","hentry","category-isbm-machine-blogs","tag-blow-molding-defects","tag-blow-molding-quality-defects","tag-injection-stretch-blow-molding-problems","tag-isbm-machine-faults","tag-isbm-troubleshooting-guide"],"_links":{"self":[{"href":"https:\/\/onestepblowmoldingmachine.com\/ru\/wp-json\/wp\/v2\/posts\/174","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/onestepblowmoldingmachine.com\/ru\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/onestepblowmoldingmachine.com\/ru\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/onestepblowmoldingmachine.com\/ru\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/onestepblowmoldingmachine.com\/ru\/wp-json\/wp\/v2\/comments?post=174"}],"version-history":[{"count":0,"href":"https:\/\/onestepblowmoldingmachine.com\/ru\/wp-json\/wp\/v2\/posts\/174\/revisions"}],"wp:attachment":[{"href":"https:\/\/onestepblowmoldingmachine.com\/ru\/wp-json\/wp\/v2\/media?parent=174"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/onestepblowmoldingmachine.com\/ru\/wp-json\/wp\/v2\/categories?post=174"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/onestepblowmoldingmachine.com\/ru\/wp-json\/wp\/v2\/tags?post=174"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}